Detonation, 10.7 ratio and 91 octane isn't working. ****UPDATES ****

[Kern Dog]

Does anyone know how to make this work?
I have a 440/493 combo. 440 block with a 4.15 stroke crank. The pistons are .017 in the hole. .39 Fel Pro head gasket. This adds up to a 10.7 compression ratio. I was told when I bought the crank, rods and pistons that it would work on 91 octane pump gas. It does if I drive it in cool weather with a meager 30-31 degree limit on the mechanical advance. I have an 850 VS carb, 2" headers, An Edelbrock RPM intake.
This sucks. It is getting warmer and I hate dealing with the pinging and poor performance.
I am running the Mopar Performance 292/509 cam installed straight up. I used this cam in 2004 when I first built the engine. At that time I had it advanced 4 degrees. I had cranking compression over 225 and it rattled like crazy. I set it to straight up and it helped, but it still isnt right. I have read that cam timing can make it possible to live with high compression and pump gas. The idea is that the cam helps bleed off cylinder pressure.
I should probably state my goals of the engine and car. I want a great running, pump gasoline engine that never rattles. I don't mind a rough idle, since I am used to it with the '509 cam. I like to actually drive the car. I just returned from a 995 mile round trip for the Van Nuys Spring Fling. I don't need a peaky race engine and I'm not expecting to commute 40 miles to work in it. Something in the middle of those is what I am looking for.
Any suggestions?

[68CoronetRT]

First off, what heads are you running? Head Volume in CC's?(IE: 84/88cc Edelbrock, 80cc 440source etc..)

My first guess would be to stick a .051 compressed headgasket(staying with a standard gasket) in there and it should lower it to around 10.5:1(I think) which would be almost ideal IF your running aluminum heads. You could go ever thicker but then you would have to run a copper gasket(not sure about these??).

If they are iron heads then you are running waaaaay too much compression for pump gas.

[Kern Dog]

I'm sorry I forgot to mention. I have the 84 cc Edelbrock aluminum heads. They are basically out of the box.
I've seen the .51 gaskets listed. I've wondered if the thicker gasket and a different cam could be enough to get me a bit more detonation resistance.

[firefighter3931]

The 509 is building too much midrange cylinder pressure and that is why it is detonating under load. 

What you need is a cam with a wide 112*lsa to flatten out the torque curve and reduce cylinder pressure. The tight lobed cam profiles spike torque over a narrow powerband and when you hit that sweet spot it will detonate if things are not right. In your case it's a combination of too much static compression and not enough octane. 

If you're stuck on that particular brand....MP makes a wide lsa version of the 509 cam that i believe has a 114* lsa.


Ron

[Kern Dog]

If you're stuck on that particular brand....MP makes a wide lsa version of the 509 cam that i believe has a 114* lsa.


Ron

Stuck on that brand...

I may have forgot to mention. I started with this cam when I built the engine. I switched to a Comp cam stick that went flat within 100 miles. The replacement cam also went flat in short time. I went back with the MP cam to save cash. I am not married to any brand. I just want reliable performance.
The wider LSA theory makes sense. Maybe I'll call Comp or Hughes and see what they recommend.
Thanks everyone, Greg

[Challenger340]

Any chance the engine is running lean ?
Exremely lean mixtures burn fast & erratic exposing too much of the cylinder walls to peak combustion temps.

10.8:1 should not be a problem on 91 Octane with Aluminum Heads, with any Cam at, or approaching 70* ABDC IVC point seat to seat timing on the 6.76" Rods, even at sea level ?

Whats the cranking pressure now ?

[Kern Dog]

I had the engine apart in Feb 2011 to hone the cylinders and put in new rings. Before the teardown it was reading at a low of 178 and a high of 190. It was smoking under heavy acceleration and I suspected the rings were wasted. They were. Luckily I didn't have to go to .040. My machinist thought that the rings wore out from running too rich. I stepped down the power valve. It only smokes black when it detonates. 6 months ago I started installing a wideband air/fuel guage to get an accurate tune. Life got in the way and the furthest I've gone with it was to have bungs welded in the collectors.
I may go ahead and check compression PSI #s to have a baseline to work from.

[jlatessa]

I thought lean mixtures burn slower, hence the need for vacuum advance at
cruise??

An O2 sensor will point you in the right direction.

Joe

[Cooter]

I too am fighting this problem right now. Too much Static Compression with Iron heads.

[Kern Dog]

Today I spoke with Ken at Hensley Performance. I bought the rotating assembly from them in 2004 and they have been really helpful. Ken suggested using a .051 Fel Pro head gasket and a milder cam with a 110 LSA. I am confused though. Everything that I have read so far has told me that a MORE aggressive cam is what is needed to bleed off cylinder pressure. It seems that going smaller would increase cylinder pressure and ADD to the problem.
I wish that I had more experience with this stuff.

[mhinders]

As far as I understand both too lean and too rich mixtures burn slower than the optimum mixture, from memory I take 12.4:1 as the optimum performance mixture. Slow cruising can run leaner mixtures to save gas.

To lower the dynamic compression, and hopefully decrease the risk of detonation,  I believe you need a later closing intake valve, either by replacing the cam or retarding your current cam. 

[Kern Dog]

I have seen ads about the .020 steel shim head gasket. Any idea why they call it a shim? Is it because it can be used along with another gasket to achieve a greater thickness? I had an idea of seeing them on the deck, followed by a Fel Pro blue composition gasket above it. This would result in a .059 thickness for a fraction of the cost of a .060 Cometic. I have 2 pair of Fel Pro .039 gaskets already...

[Cooter]

I have seen ads about the .020 steel shim head gasket. Any idea why they call it a shim? Is it because it can be used along with another gasket to achieve a greater thickness? I had an idea of seeing them on the deck, followed by a Fel Pro blue composition gasket above it. This would result in a .059 thickness for a fraction of the cost of a .060 Cometic. I have 2 pair of Fel Pro .039 gaskets already...

In a word, No....The "Shim" gasket means just that, it is a Single 'Shim' style gasket instead of the Fel-Pro "blue" which is multi-layer, as is the Cometic gaskets.

Stacking up Head gaskets is NOT a good idea. I have done it on the race car AT THE TRACK to make the next round, but NEVER on something I want to last. EASY way to cause all kinds of problems like Leaking coolant into combustion chambers/Vice versa.
Bite the bullet and get the GOOD gaskets, do it one more time, and be done with it. Oh and BTW, I know it's harder to do than it sounds, but listening to too many folks who post Opinions, can cause you to do what I did. I was told my engine would "ok" with iron heads and now it runs on 100 Octane.
Shoulda listened to my instincts and just built a low comp Nitrous engine like I always did. Stick with what YOU KNOW is the real thing to do here. That is to lower the compression the tried and true way. You sound like you cannot afford to "Experiment" with fifty different options here, so Thicker head gaskets is the only TRUE way YOU KNOW to lower it.

[justcruisin]

I Have been following this thread with interest, I would have to question installing a thicker head gasket, my understanding is that a tight quench of around .040" is a good way of helping with detonation. You are at .057" now, is adding another .012" going to help or make it worse. You might find that more timing is needed to compensate for the slower burn. I would think that a cam swap would be the right way to go. Before you head in any direction I would be doing plenty of research, and making sure your fuel curve isn't to lean.

[Kern Dog]

Today I spoke with William at the Comp Cams tech line. He believes that the idea of using a milder cam is flawed like most everyone else thinks. He liked the idea of using the thicker head gasket, but to stay with the '509 cam. I was surprised that he didn't try to sell me a camshaft. He said that I should be able to make things work with a small drop in compression and some tuning.
I hear quite often that my current combination should work. The engine runs cool. The timing isn't cranked to 40 degrees. I run vacuum advance because Rick Ehrenberg from Mopar Action magazine feels that it promotes complete combustion. Maybe I could try plugging the cannister and see how it runs.

[cdr]

if you are running vacuum advance with almost 11 to 1 compression ,THAT is going to detonate,unplug it & set your total timing at 36 & go drive it,tune from there.

[firefighter3931]

if you are running vacuum advance with almost 11 to 1 compression ,THAT is going to detonate,unplug it & set your total timing at 36 & go drive it,tune from there.

Bingo ! Disconnect that stupic vacuum advance and re-tune the car. With the closed chamber E-Heads set the total at 35* because that's where it will make best power.  

I run vacuum advance because Rick Ehrenberg from Mopar Action magazine feels that it promotes complete combustion.

I get tired of hearing this complete combustion arguement   Vacuum advance is an emissions thing and designed to work with a stock engine that makes 18-20 inches of vacuum at idle. Throw a lumpy cam in the mix and it becomes a tuning headache !!!  

Every car i've tuned removing the vacuum advance has run a LOT better !!!!    

If you have 185 psi (or less) cranking pressure with a tight quench/closed chamber aluminum head the problem is tuning ; too lean or timing needs some tweaks.  



Ron

[HPP]

If you don't want to get into the engine, you could always try water/methanol injection. http://www.snowperformance.net/

[cdr]

if you are running vacuum advance with almost 11 to 1 compression ,THAT is going to detonate,unplug it & set your total timing at 36 & go drive it,tune from there.

Bingo ! Disconnect that stupic vacuum advance and re-tune the car. With the closed chamber E-Heads set the total at 35* because that's where it will make best power. 

I run vacuum advance because Rick Ehrenberg from Mopar Action magazine feels that it promotes complete combustion.

I get tired of hearing this complete combustion arguement  Vacuum advance is an emmissions thing and designed to work with a stock engine that makes 18-20 inches of vacuum at idle. Throw a lumpy cam in the mix and it becomes a tuning headache !!! 

Every car i've tuned removing the vacuum advance has run a LOT better !!!!   

If you have 185 psi (or less) cranking pressure with a tight quench/closed chamber aluminum head the problem is tuning ; too lean or timing needs some tweaks. 



Ron

i will repeat again,, disconnect the vac advance & retune!!!!!!!

[Kern Dog]

I still need to finish installing the air/fuel wideband guage. Is it fair to say that it would detect any difference in combustion when I disconnect the vac advance?
I know that with many things, it is the small details that can make the difference. I should have mentioned the vacuum advance in the first post. Thank you everyone.

[Musicman]

Vacuum advance is an emissions thing and designed to work with a stock engine that makes 18-20 inches of vacuum at idle.

I wouldn't call vacuum advance an emissions thing per say... the "Ported Vac" your plugging into is an emmisions thing yes, and it will interfere here, because as you said "Vacuum advance is designed to work with a stock engine that makes 18-20 inches of vacuum at idle."

[cdr]

yes the tune ,air fuel ratio on the wide ban will change with different timing.

[Budnicks]

if you are running vacuum advance with almost 11 to 1 compression ,THAT is going to detonate,unplug it & set your total timing at 36 & go drive it,tune from there.

I agree, could be too much mechanical advance too, added with what the vacuum advance adds, it could be tamed down also, there are adjustable vacuum pods on MP CEI distributors you can turn it down significantly &/or even try to change it mechanically with spring & weights... to have a total of 36* when the all the advance is in... Possibly if you have 36* in the distributor total, with the vacuum line unplugged & then have the vacuum advance added it's probably in the 50* range at part throttle... could be an issue, that's what I've done anyway, with an adjustable vacuum advance pod on a MP CEI Chrome Box/ECU & MP CEI Adj. vacuum pod on the MP CEI Distributor, from Mancini Racing... a different camshaft would make a world of a difference also, there's allot better cams than a MP 509 Purple Shaft for you combo out there, as some have mentioned here already... Good Luck

[69wannabe]

I agree with Ron completely about disconnecting the vacumm advance!!!! I have built a lot of engines for people in my area (mild 383's and 440's) and have never hooked up the vacumm advance. Tried adjusting the canister to where it doesn't advance too much and still plugging it off makes the engine's run better to me. Met a guy a couple years back with a 69 general lee charger and he asked my advise on a small issue he was having, went down the road and I told him to pull off for a sec so I could try something. Plugged the vacumm advance off and we drove down the road and it was smoother and ran more solid. He had read the same article about complete combustion and I just said well it runs great now so what do you want to do?? Hook it back up so that it runs like crap and his was pinging too or plug it off and it stopped pinging and ran much better?? He left it plugged off and has been happy with it every since!! If Ron says plug it off then that's what I would do!! He steered me in the right direction with some timing issues I was having with my 493. I haven't been on the forums long but this guy knows his stuff for sure!!!

[Kern Dog]

I pulled the vacuum line yesterday and took a 175 mile drive today. The part throttle ping is gone, but I still get some at around full throttle. Until I make some internal changes, I may need to run a few gallons of 110 Sunoco in a tank of 91. That ought to raise it to 95-96 octane.

[firefighter3931]

I pulled the vacuum line yesterday and took a 175 mile drive today. The part throttle ping is gone, but I still get some at around full throttle. Until I make some internal changes, I may need to run a few gallons of 110 Sunoco in a tank of 91. That ought to raise it to 95-96 octane.

Good work....you're moving in the right direction ! 

Now, you need to get that wideband installed and get some AFR readings at WOT to see if it's a lean condition and decide from there where to go 



Ron

[b5blue]

I ran a 509 for 6 years in my 440, forget vacuum anything, keep ignition system flawless (Firecore plug wires? Heat range of plugs?) and tune for WFO till you get it. It was VERY picky about fuel brand and this was pre ethanol, you may need octane booster.   

[Cooter]

I pulled the vacuum line yesterday and took a 175 mile drive today. The part throttle ping is gone, but I still get some at around full throttle. Until I make some internal changes, I may need to run a few gallons of 110 Sunoco in a tank of 91. That ought to raise it to 95-96 octane.

Exactly where I am at with the Challenger engine. That is why I rec. that you swap out known comp. lowers like head gaskets. Once you go so far with tuning, it really gets down to too much static Compression. only way round it is to lower it.

[Kern Dog]

I have been reading up on "Quench". Pretty interesting stuff.
With flat top pistons and a closed chamber head, it goes like THIS: As the piston rises up on the compression stroke and closes in on TOP dead center, the incoming mixture compresses and gets pushed away from the flat portion of the head and toward the pocket where the valves and spark plug are. This sudden movement away from the one side of the head causes turbulence while cooling any potential hot spots. This "Quench" effect is most effective in a limited range. Once the distance between the piston and cylinder head get too far away, it begins to become less effective.
The above is a summary of the many, many articles, posts and threads that I have read. I am often a trusting person, but I still am amazed and a bit unsure to fully accept it. I currently am .56 from the head at TDC and many sources state that quench is lost at .060 and larger distances.  This logic means that even with detonation at 10.8, if I switch to a thinner head gasket to get the piston closer to the head for better quench, I will actually detonate less even with higher compression? Can you see how someone that has never personally experienced this can be skeptical? Sure, some of this is a money issue. I could spend money on some .027 Cometic MLS gaskets, a bigger cam with new lifters, timing set and gaskets....Spend almost $600 to learn that everyone is right. The .027 thickness would get me to .044 from the head which is dead center of Ideal for quench. It also would put me right at 11 to 1 compression. I'm sure that anyone else in my position would be skeptical, right?

[justcruisin]

Right, no guaranties, best bet, work with what you have, get the wide band in and dial in your fuel and ignition, see where you end up with your current set up.

[HPP]

Or you could spend $450 for a water/methanol injection, bolt it on in an afternoon, and use washer fuild instead of Sunoco 110.

Yes, with an assembled engine, I'd be skeptical to change as well. Anytime I've used quench, it was designed in from the begining. But I was also able to produce power and mileage figures from using it that rivaled many new vehicles for mileage and produced power from a milder combo that was compareable to many more expensive builds. It is an effective and practical way to increase compression efficiency that is used in many late model engien designs.

[Kern Dog]

My air cleaner is up against the hood as it is now. I'm using a dropped base too. I am guessing, but wouldn't the water/methanol injection involve some sort of carburetor plate delivery? If it were port injected, that may be interesting.

[Cooter]

"Quench" ain't worth two pinches of puppy sh*t if running shi*ty fuel. Today's "91" is like yesterdays 87....

I can dump TODAY'S 100 Octane in the Chally and notice a difference right away. 93 To 100 and notice an imediate difference? Yeah, I'll buy that 93 "pump" fuel is actually 93 octane.

[HPP]

My air cleaner is up against the hood as it is now. I'm using a dropped base too. I am guessing, but wouldn't the water/methanol injection involve some sort of carburetor plate delivery? If it were port injected, that may be interesting.

It does require a delivery nozzle to be added to the system, however there are options to its mounting. If you have a single plane intake, you could mount it directly into a plenum wall. If it is a dual plane, then you would want a plate to enable it to spray into both sides. Although I suppose if you were so inclined, you could put two nozzles in place. You also can put it upstream of the throttle plates, but that method may be best left to efi applications.

The appeal of the injection is that it is on par with loading your tank with 116 octane. If your on the edge of detonation, it will not only solve that issue but because of the cooler, denser charge, can also step up horsepower as well. Reports of an additional 5-35 horses and torque inscreases of 25-50 lb ft over optimal none injected tune ups are not uncommon.

[Kern Dog]

I have the Edelbrock RPM intake. It is a dual plane. I wonder if I could drill and tap for fittings....One for each plane. I have never considered such a thing, but it does sound interesting.

[HPP]

You mightwant to talk to them about specifics of yourset up. I haven't comeplted mine tobe able to give youpin point advice. Google Snow Performance and you can find plenty to read.

[Musicman]

I have the Edelbrock RPM intake. It is a dual plane. I wonder if I could drill and tap for fittings....One for each plane. I have never considered such a thing, but it does sound interesting.

Snow uses/sells a spacer plate that goes under the carb, but if done "correctly" it should be possible.. You just need to ensure an even non-biased dispersal.

[Kern Dog]

I looked at some kits on the Summit racing site.
I have no room to use a plate system. The air cleaner is so close to the hood, the clearance could be measured with a feeler guage.

[firefighter3931]

I looked at some kits on the Summit racing site.
I have no room to use a plate system. The air cleaner is so close to the hood, the clearance could be measured with a feeler guage.

Change the intake manifold 

You can easily fit a Holley Street Dominator single plane with a 1in spacer using a drop base air cleaner assembly under the stock hood. 


Ron

[Kern Dog]

I have read that the intake you speak of is a decent piece. The Performer RPM I run has it beat on power though.

[firefighter3931]

I have read that the intake you speak of is a decent piece. The Performer RPM I run has it beat on power though.

Actually, the Street Dominator makes more horsepower than the RPM dual plane.....it did in every magazine article i've read. I also compared both on my own 446 when we had it on the dyno and the Holley SD was the clear winner. 


Ron

[Kern Dog]

Man, I'm lucky that I have had the time to mess with this!
Short of pulling the engine and installing some dished pistons, the "fix" according to some sharp guys seems to center around the CAMSHAFT.
I have asked about this on other web forums. I've received some good advice and some stuff that made me wonder...
Hensley: "You need a thicker head gasket ans a smaller cam" Really? Wouldnt a thicker gasket reduce quench and increase detonation?
Comp Cams: "That '509 cam should be fine, you just need to use a thicker head gasket to lower compression" Again...what about quench?
Mancini:  " Yeah, a bigger cam would help. So would a thicker head gasket."

Hardly anyone in over 200 responses in various threads here, on Fabo, FBBO and Yellowbullet has thought that a thicker head gasket is a good idea. One constant though is to CHANGE THE CAM A more aggressive cam will have the ability to bleed off more cylinder pressure AND deliver more power.
I did a cranking compression test and got some interesting info: 220 in the highest hole, 210 in the lowest. This confirms that the engine is trapping faaaar too much pressure. A bigger cam is a must. Using an online calculator, my static compression is 10.73 and my DYNAMIC compression in 8.99. Experts say that an engine needs to be below 190 cranking compression and have a dynamic ratio below 8.0 to run fine on 91 octane.

Here is a cam I am considering. It is a hydraulic roller.
http://www.hughesengines.com/Index/products.php?browse=category&level0=QmlnIEJsb2NrICA0MTMtNDI2LTQ0MCAoUmFpc2VkIERlY2sp&level1=Q2Ftc2hhZnQ=&level2=Um9sbGVyLCBIeWRyYXVsaWM=&searchmode=partnumber&partid=24186

The duration isn't a whole bunch more than the 248 of the '509 cam, but it has a 110 LSA and a nice increase in lift. I will be using 1.6 ratio aftermarket aluminum rocker arms in a kit I bought from Mancini racing.

[justcruisin]

Good to see you have done plenty of research before handing over the gold. I'm sure with a drop in compression via the cam you will have a sweet runner. Fwiw, the dynamic on my engine is 8.2 with a cranking compression of 180 and it runs fine on 91 all though I choose to run it on 93.

[firefighter3931]

Look at response #3 in this thread and you'll see someone allready suggested that the cam was your problem   



Ron

[Kern Dog]

Yeah... I can be a little slow to catch on sometimes.
In the past, I have often made impulsive choices that proved to be wrong for me. Right here and now, I'm trying to cover all the bases to make the right decision. While many have suggested a cam change, NOBODY has spelled out the one that worked for them. I'm sure that others have engines similar to mine. I wish that I could hear from those guys!

I called Hughes this morning but their guys were all at INDY for some Mopar show.
I guess it will have to wait until Monday.

[firefighter3931]

Give Dwayne Porter a call 802-951-1955 and tell him what you got and how you drive the car. He can spec you a cam and it will run fantastic. Dwayne specializes in BB Mopar and is a master cylinder head porter and cam guru. 

I'm pretty sure he's going to tell you it's detonating because of the midrange cylinder pressure which is a product of a tight LSA and too short of a duration@.050 which is closing the intake valve too early. 


Ron

[Kern Dog]

Thank you for the referral. I have tried the number twice in the last 3 days. It rings and rings....He must be REALLY busy! I'll try again tomorrow.

[Kern Dog]

I got to talk with Dwayne today. What a helpful guy.
I couldn't squeeze a specific cam recommendation from him even though I tried. He did agree that a cam with a later intake closing would help.
First off, he was surprised at the cranking PSI #s I had. He said that THIS build shouldn't have #s that high with the long duration of the '509 cam. He suggested trying another compression guage. I told him I was installing 1.6 ratio adjustable rocker arms. He liked the idea and suggested to REcheck the cranking PSI afterwards. I asked about the effects of retarding the cam to delay the intake closing. He liked that too and again suggested to check cranking PSI.
Dwayne talked a lot about tuning the distributor to slow the advance curve. He said that a slower curve would result in reduced performance but would also reduce spark knock.
He thought that the real cure to the detonation would be to cut the block to allow the pistons to sit at zero deck. Then, have the valve side of the pistons milled .040 to reduce compression. This would improve quench while reducing compression. I'm not willing to pull the engine out anytime soon, so I'm going to focus on the cam and ignition.

[firefighter3931]

Dwayne is sharp, no doubt about that !  Did you degree your cam in ? I've been wondering why it has so much cranking pressure as well ?  If it wasn't degreed in properly ; the cam could be too far advanced and closing the intake valve too soon. 

If you didn't want to open the engine up a meth injection kit with a street dominator intake manifold would be your easiest route. Lots of guys run high compression on pump gas with meth and it works fantastic. 


Ron

[flyinlow]

Just curious . When does the methanol system inject? Just acceleration? How big of a tank do you need to cover a full tank of gas?

[Kern Dog]

I  am not very familiar with the operation of the Methanol kits.
Here is an update:
The compression guage that I was using has a flaw: The needle starts at 30 PSI ! I tested the engine using a defective guage and it gave false/high readings!
I didn't notice it until I already had the 1.6 rocker arms in the left side. I went for the guage to test the difference between the left 1.6 side and the right stock 1.5ish side. All the RH cylinders showed to be between 25 and 27 lbs lower than before, now in the 190-195 range. AFTER installing the 1.6 rockers on both sides, the numbers didn't drop much. The 1357 side is between 185 and 188 and the right side is between 187 and 191.
The spark plugs were replaced along with the plug wires. The car idles a little smoother, but also a little lower. Power may have increased, but not a whole lot. ZERO detonation, but to be fair, I have a 50-50 mix of 110 and 91 in the tank. I'd need to run this batch out and fill up with 91 to know if this made any difference. I was tempted to retard the cam when I finished the rocker installation, but I figured that since the cranking PSI didn't drop much, I probably should move forward with a cam swap. No biggie...I figured that any high performance cam, especially a solid cam, needs an adjustable valvetrain.
All this chatter about guys running low 11s and high 10s with 500 inch B body cars has me anxious. The thought that a switch to a bigger cam (Along with the appropriate carb and ignition tuning) could unleash more power, it is very tempting!

[2Luke2]

I'm glad to hear you're getting it straightened out. Appreciate the information as you go along!

[firefighter3931]

Those cranking comp numbers seem more in line. 

I still think a cam swap is in your future if you want to run this beast on 91 pump swill 


Ron

[Budnicks]

  What's the current prognosis, what parts, gaskets & camshaft, did you finally settle on, just curious....  we need an update, good luck

[Kern Dog]

Hey guys...
I have a pile of parts ready to go in. YES I decided to go with a bigger camshaft. I bought a Lunati Solid flat tappet, 316/326. It has 261* INT and 271* EXH @ .050 and with my 1.6 rockers, the lift is .578 INT and .600 EXH. After valve lash, it is .558/.578 with a 108 LSA. The intake closing is almost 10 degrees later than the '509.
I ordered those cool EDM solid lifters that have the tiny oiling hole in the face of the lifter. This ensures a steady stream of oil to the cam lobes. I have a new Edelbrock timing set, all the gaskets too. NEW Milodon 6 quart HEMI oil pan and pickup AND the new composite windage tray from Jegs that uses NO gaskets! It has a twin rib rubber seal similar to what is used on the Mopar Performance 904 and 727 transmission pans.

I've taken too many shortcuts in the past, thinking that I could just throw parts together and expect it all to work out. My better sense here is driving me to actually degree the cam instead of just installing it "dot to dot". I have read numerous times about checking piston to valve clearance, but have never done that either. I want to make sure that all the parts are properly working together so it makes power and holds together. All of these upgrades have been in an effort to improve streetability and make more power. I have been getting anxious with this stuff... thoughts of drag racing have been running through my head. I'm a big fan of making a car handle well, so the car is at a disadvantage to a dedicated drag car. Big T bars, sway bars, wide, low profile tires at all corners don't make a great drag car. I still hope to crack into the 11s though.
Once I get someone to help me with degreeing the cam, I'm jumping in to work on it.

[Cooter]

I dunno, if you got enough motor, a buddy here has a badass LS powered Vette, complete with stupid big wheels/low profile tires that runs 6.40's 8th mile.

[Kern Dog]

Forgive my lack of understanding, but is there a ballpark formula to determine a 1/4 mile estimate based on an 1/8th mile ET?

[firefighter3931]

Forgive my lack of understanding, but is there a ballpark formula to determine a 1/4 mile estimate based on an 1/8th mile ET?

Take the 1/8 mile ET and multiply by 1.57   


Ex ; 6.40 x 1.57 = 10.04  1/4 mile ET



Ron

[Budnicks]

Hey guys...
I have a pile of parts ready to go in. YES I decided to go with a bigger camshaft. I bought a Lunati Solid flat tappet, 316/326. It has 261* INT and 271* EXH @ .050 and with my 1.6 rockers, the lift is .578 INT and .600 EXH. After valve lash, it is .558/.578 with a 108 LSA. The intake closing is almost 10 degrees later than the '509.
I ordered those cool EDM solid lifters that have the tiny oiling hole in the face of the lifter. This ensures a steady stream of oil to the cam lobes. I have a new Edelbrock timing set, all the gaskets too. NEW Milodon 6 quart HEMI oil pan and pickup AND the new composite windage tray from Jegs that uses NO gaskets! It has a twin rib rubber seal similar to what is used on the Mopar Performance 904 and 727 transmission pans.

I've taken too many shortcuts in the past, thinking that I could just throw parts together and expect it all to work out. My better sense here is driving me to actually degree the cam instead of just installing it "dot to dot". I have read numerous times about checking piston to valve clearance, but have never done that either. I want to make sure that all the parts are properly working together so it makes power and holds together. All of these upgrades have been in an effort to improve streetability and make more power. I have been getting anxious with this stuff... thoughts of drag racing have been running through my head. I'm a big fan of making a car handle well, so the car is at a disadvantage to a dedicated drag car. Big T bars, sway bars, wide, low profile tires at all corners don't make a great drag car. I still hope to crack into the 11s though.
Once I get someone to help me with degreeing the cam, I'm jumping in to work on it.

Thanks for the update..

[SRT-440]

This is an interesting thread. Meth/Alky kits work great...I run 100% meth on my GN and that's the only way it stays alive with 26#'s of boost. Couldn't get it out of the 12's without it..now it run's 11.2x with zero knock. 87-91 octane around town and 116 when I put my foot it it.

I need a kit on my RR...last compression test it got cracked out  220ish+ PSI per cylinder..lol.

[69charger440]

With that cam check:

Valve retainer to Valve guide clearance.
Valve retainer to Rocker arm clearance through full rotation
Coil Bind on the springs.

Always a great ideal to check piston to valve clearance... 

[Kern Dog]

Thanks for the suggestions.
Today I bought a degree wheel kit. It has the wheel, the dial indicator, 2 light springs to replace the standard valvesprings, a piston stop and some instructions.

[Kern Dog]

#1 picture didn't come through...
Here it is:

[Kern Dog]

Check out these lifters!
EDM style. That wide recess in the middle is strange looking!

[Kern Dog]

Forgive me if you're already familiar with this stuff. It is new to me.
The EDM lifters have a hole in them to deliver oil from the lifter oil gallery, through the body of the lifter to the cam lobes.
The picture shows. The Lifter on the left shows a small hole in the recessed portion. Thats where the oil enters. The lifter on the right shows the base of the lifter where the oil exits.
With holes this small, I'll have to be even MORE diligent about oil changes.

[Kern Dog]

I plan to degree the cam this weekend if I can get the right pushrods. I have to mock it up and measure. If I can't get the pushrods locally, I'll have to order through Summit or Jegs.
I just read how to measure Piston to Valve clearance with the heads on.

[firefighter3931]

With that cam check:

Valve retainer to Valve guide clearance.
Valve retainer to Rocker arm clearance through full rotation
Coil Bind on the springs.

Always a great ideal to check piston to valve clearance... 

Good suggestions 

Just to add to that ; you should also be looking at the spring rate that is required for that cam with a 1.6:1 rocker ratio. INMHO you will need a better valvespring than is on the head, currently. 

Something like the Comp 928 or Isky 8005 would fill the bill. When you break-in the cam the inner springs will have to be removed. Both of these are double springs and too much pressure during the break-in procedure will wipe the cam and lifters. 



Ron