i think I heard that with aluminum heads you can handle a full ratio of compression. We figured out that I have a set of old number 12-1 pistons (I know that specks make a compression difference) in my 440. I had planned to run this engine on E-85 but life has changed and I am looking to get this thing comfortably streetable. Is one brand of head better than another ? Thanks ..
Quote from: Highbanked Hauler on February 29, 2020, 10:13:03 PM
We figured out that I have a set of old number 12-1 pistons (I know that specks make a compression difference) in my 440.
Humor me here OK ?
IMO, highly doubtful you've got Pistons that yield anywhere near "12-1" compression in the
real world ?
So before getting into things like Dynamic Cylinder Pressure/Camshafts Aluminum Head heat dissipation, etc. etc....
what Pistons are you running, and why do you believe they are "12-1" ?????
Very simple. What is the "old number"
Quote from: c00nhunterjoe on March 01, 2020, 01:00:48 PM
Very simple. What is the "old number"
To be up front first, I am not now or ever will be an engine person and I understand the doubt factor. It would be a lengthy story how I ended up with the motor which is a 72 . I got it in 2013 with less than 50 miles on it from running in the power tour in Detroit and a few burnouts in the street. His car never got finished.
In looking through the spark plug hole I could see the number ( 7025 ) and .030 which I am assuming is 30 over. There may have been more # but thats what I could see. It has a Comp Cam with a valve lift of .507 intake and .510 exhaust with a 106 intake centerline. 906 heads with "long" valves, 1-6 Crane rockers ..
Quote from: Challenger340 on March 01, 2020, 11:07:54 AM
Quote from: Highbanked Hauler on February 29, 2020, 10:13:03 PM
We figured out that I have a set of old number 12-1 pistons (I know that specks make a compression difference) in my 440.
Humor me here OK ?
IMO, highly doubtful you've got Pistons that yield anywhere near "12-1" compression in the real world ?
So before getting into things like Dynamic Cylinder Pressure/Camshafts Aluminum Head heat dissipation, etc. etc....
what Pistons are you running, and why do you believe they are "12-1" ?????
Please know I do not have an ego to polish nor am I delusional nor am I building an 8 sec. car. Prior post should give you an idea. I am going on what I was told when I got it. :shruggy: I do appreciate any input.
I believe 7025P is the equivalent of the TRW 2295 (13 cc dome) which would yield around 12-1 with 85cc head. 0.022" gasket and 0.020" deck clearance.
Edelbrock 88cc head (60185), and a Felpro 0.051 gasket (1039) will probably get you to where you need to get.
Your cam selection might matter too.
Quote from: BSB67 on March 01, 2020, 04:57:48 PM
Edelbrock 88cc head (60185), and a Felpro 0.051 gasket (1039) will probably get you to where need to get.
Your cam selection might matter too.
Thanks, do you feel that combination would get it down to the premium gas range ? Can the top of the piston be milled off any ?
For the money you will spend on tear down, milling pistons, and rebalancing, you could buy a better piston. I beleive quench with those pistons will not be ideal, but as stated, it will run fine on pump gas. What head gasketz are currently on it? And are the heads and block cut? If not and running a traditional felpro gasket, odds are it is not a 12:1 mill. If you have the cam card or at least grind number, get some cranking compression numbers and post.
I would agree on the under 12-1 as the owner said he drove it about 100 miles in the power tour and I asked him how did he get race gas in the city and he said HE DIDN'T.
At a glance aluminum heads go from $1000 to $2000 a set and the pistons I saw were $700 plus rings, keepers and whatever else. So pistons would be half the price of heads but the motor comes out and apart. I am $2600 into the motor so it could be worse.
PART # 21-225-4
GRIND NUMBER CRB XE284H 10 ? Comp Cams
Compression I will have tomorrow.
whoooaaa !
Hold on there... that's what I figured.... and you are nowhere even close to 11:1.... let be 12:1
7025 are indeed identical to the L2295 Speed Pro, in fact TRW and Speed Pro used to use the same Forgings back in those days.
They are 10.37:1 Compression Ratio using an Fel-Pro Composition Gasket (.039") and an 88 CC Cylinder Head installed in a 10.72" Deck Height UN-Milled Block.
Meaning, that unless your Block has been Milled fairly extensively ?(like more than .010")..... those Pistons are still .050" to .060" down hole at TDC and you are likely still well below 10.5:1.
Here are the L2295's same as your 7025's
https://www.summitracing.com/parts/trw-l2295f30
As mentioned....
* disable the ignition
* wire your throttle plates wide open
* remove all 8 Spark Plugs
* install a decent quality compression tester in each cylinder one at a time
* Crank Engine.... allow 4 Bumps ONLY on the Needle per cylinder.... try and note the 1st "bump" as 75% of the 4th and FINAL "bump" and record that 4th Bump as final pressure for that Cylinder.
Report back.
Yep....the 2295's sit .050 below deck so with a std .040 gasket and 84cc E-head the comp works out to ~10.5:1 :2thumbs:
I know someone who ran that exact combo with a Comp Solid 294S cam and it had plenty of piston to valve clearance. :yesnod:
Ron
Quote from: firefighter3931 on March 02, 2020, 09:10:21 AM
Yep....the 2295's sit .050 below deck so with a std .040 gasket and 84cc E-head the comp works out to ~10.5:1 :2thumbs:
I know someone who ran that exact combo with a Comp Solid 294S cam and it had plenty of piston to valve clearance. :yesnod:
Ron
I like that grind cam. Alot of street guys think its too big.... glad to hear it still used.
Just to answer your original question after my build I chased ping/knock and aluminum heads finally cleared that up. I used Sidewinders:
http://www.mopartsracing.com/parts/Sidewinder.html
Real happy with them using 750 with CH4B-HP exh manifolds and Mopar Road Runner cam. :2thumbs:
Quote from: c00nhunterjoe on March 02, 2020, 10:22:00 AM
Quote from: firefighter3931 on March 02, 2020, 09:10:21 AM
Yep....the 2295's sit .050 below deck so with a std .040 gasket and 84cc E-head the comp works out to ~10.5:1 :2thumbs:
I know someone who ran that exact combo with a Comp Solid 294S cam and it had plenty of piston to valve clearance. :yesnod:
Ron
I like that grind cam. Alot of street guys think its too big.... glad to hear it still used.
So since it is established that mine is 10.5 comp. (which is great) then a "thick" head gasket this thing should be getting down in pump gas range right ? :shruggy: Thats what I am after. The cam number is posted from the paper I have.
Compression gauge is dead..
I am in the process rebuilding NOT restoring the car, it is NOT on the road. and I use 93 to start it New compression tester was to long to get past a couple of tubes
COMPRESSION No. 1 90 150 180 187 No 3 header in the way 4 bumps count cam numbers on a prior post
No 2 100 120 180 185 No 4 100 130 180 184 Carb. off of the motor The third bump was consistently 180
No 5 header in the way No 6 header all plugs out
No 7 90 150 180 185 no 8 90 120 180 185 ignition unplugged
1.6 Crane rockers.
We are educated guessing the numbers based on 3 main variables still. We either need compression numbers to get it accurate or it torn down to measure before you can go much further with reccomendations. ASSUMING it is 10.5:1, that is pump gasable on iron heads 98% of the time. What fuel are you currently running and why do you not run 93? Really need those compression numbers.
Still a TON of variables that need to be nailed down more precisely BEFORE making Fuel grade decisions ?
Get some compression numbers on whatever current Camshaft is in there ? I must have missed it... WHAT cam is in it ?
or,
tear a Head off and MEASURE how far down the flat portion of the Pistons are at TDC ?
"Quench" plays an important role when approaching the limits of the fuel, and although I dis-agree with many around optimum quench being "sub-.050" on all BB Mopars ?....
that said,
if your Pistons(flat portion) are indeed .050" down at TDC and 10.5:1 Compression Ratio is attained using a .040" Head Gasket.... then your TOTAL "quench" of .090" (.050 + .040) is a little high.... and I would suggest an Elevation/Dynamic Compression limit with whatever Camshaft profile closing point of around MAX 155 psi for 91 Octane Pump Fuels on a full timing curve(34*/36*).
Quote from: Highbanked Hauler on March 02, 2020, 02:07:34 PM
I am in the process rebuilding NOT restoring the car, it is NOT on the road. and I use 93 to start it New compression tester was to long to get past a couple of tubes
COMPRESSION No. 1 90 150 180 187 No 3 header in the way 4 bumps count cam numbers on a prior post
No 2 100 120 180 185 No 4 100 130 180 184 Carb. off of the motor The third bump was consistently 180
No 5 header in the way No 6 header all plugs out
No 7 90 150 180 185 no 8 90 120 180 185 ignition unplugged
1.6 Crane rockers. REPEAT
Quote from: Highbanked Hauler on March 01, 2020, 05:32:38 PM
Quote from: BSB67 on March 01, 2020, 04:57:48 PM
Edelbrock 88cc head (60185), and a Felpro 0.051 gasket (1039) will probably get you to where need to get.
Your cam selection might matter too.
Thanks, do you feel that combination would get it down to the premium gas range ? Can the top of the piston be milled off any ?
Yes. It can be, but you don't need to.
Quote from: Highbanked Hauler on March 02, 2020, 02:07:34 PM
I am in the process rebuilding NOT restoring the car, it is NOT on the road. and I use 93 to start it New compression tester was to long to get past a couple of tubes
COMPRESSION No. 1 90 150 180 187 No 3 header in the way 4 bumps count cam numbers on a prior post
No 2 100 120 180 185 No 4 100 130 180 184 Carb. off of the motor The third bump was consistently 180
No 5 header in the way No 6 header all plugs out
No 7 90 150 180 185 no 8 90 120 180 185 ignition unplugged
1.6 Crane rockers.
I'll still stay with my original recommendation, considering the information we have at this time. But I would not buy anything until you pull a head and start measuring. If you had an aluminum head on it now with a blow of 185 psi, you would probably get away with pump gas with the right tune.
But for sure, between the head selections that are out there, and the head gasket options, you can probably get nearly any CR you might want.
So what is the thickest gasket that can be used because I would rather not by aluminum heads I am on damage control now. :brickwall:
Quote from: Highbanked Hauler on March 02, 2020, 08:01:01 PM
So what is the thickest gasket that can be used because I would rather not by aluminum heads I am on damage control now. :brickwall:
you need alum heads In my opinion.
Quote from: cdr on March 02, 2020, 09:08:45 PM
Quote from: Highbanked Hauler on March 02, 2020, 08:01:01 PM
So what is the thickest gasket that can be used because I would rather not by aluminum heads I am on damage control now. :brickwall:
you need alum heads In my opinion.
Probably Right. Its going to take more than a head gasket to get down to 160, IMO. What gasket do you have know?
Quote from: BSB67 on March 02, 2020, 09:14:46 PM
Quote from: cdr on March 02, 2020, 09:08:45 PM
Quote from: Highbanked Hauler on March 02, 2020, 08:01:01 PM
So what is the thickest gasket that can be used because I would rather not by aluminum heads I am on damage control now. :brickwall:
you need alum heads In my opinion.
Probably Right. Its going to take more than a head gasket to get down to 160, IMO. What gasket do you have know?
The engine was complete when I got it, I just bolted stuff to it. As I said I was planning to run it on E-85 so I didn't think compression was an issue but that was 7 years ago and life has changed. So it comes down to pistons right ? CAN aluminum heads compensate for the compression if thats the issue ?
Yes that's what I did. Aluminum heads move heat faster allowing higher compression. (Or like lowering compression from 12 to 11.) The 6 to 1 rockers add lift to the cam as factory is 5 to 1. (Also) :scratchchin:
Still dont know enough without a tear down to know what gasket you have. I ran 93 blowing 200 psi on my 383 at 3000 ft, but i had good quench and closed chamber iron heads. You do not have that advantage. I disagree with the 150 psi as max on pump gas, but i can agree that 150 is a safe number for a failsafe against a rookie tuner. That is a whole seperate topic.
Given the current information on hand about the build, and the lack of teardown being on the table, i see 2 options IF detonation is an issue on your current combination as we havnt yet heard why the topic has come up. You stated that the previous owner ran 93 in it??? That said. Race fuel, or a cam profile that lowers the dynamic compression ratio to the desired level.
Quote from: Highbanked Hauler on March 03, 2020, 08:55:46 AM
Quote from: BSB67 on March 02, 2020, 09:14:46 PM
Quote from: cdr on March 02, 2020, 09:08:45 PM
Quote from: Highbanked Hauler on March 02, 2020, 08:01:01 PM
So what is the thickest gasket that can be used because I would rather not by aluminum heads I am on damage control now. :brickwall:
you need alum heads In my opinion.
Probably Right. Its going to take more than a head gasket to get down to 160, IMO. What gasket do you have know?
The engine was complete when I got it, I just bolted stuff to it. As I said I was planning to run it on E-85 so I didn't think compression was an issue but that was 7 years ago and life has changed. So it comes down to pistons right ? CAN aluminum heads compensate for the compression if thats the issue ?
I'm confused. I think I've answered your question twice, maybe three times.
Quote from: BSB67 on March 03, 2020, 01:00:16 PM
Quote from: Highbanked Hauler on March 03, 2020, 08:55:46 AM
Quote from: BSB67 on March 02, 2020, 09:14:46 PM
Quote from: cdr on March 02, 2020, 09:08:45 PM
Quote from: Highbanked Hauler on March 02, 2020, 08:01:01 PM
So what is the thickest gasket that can be used because I would rather not by aluminum heads I am on damage control now. :brickwall:
you need alum heads In my opinion.
Probably Right. Its going to take more than a head gasket to get down to 160, IMO. What gasket do you have know?
The engine was complete when I got it, I just bolted stuff to it. As I said I was planning to run it on E-85 so I didn't think compression was an issue but that was 7 years ago and life has changed. So it comes down to pistons right ? CAN aluminum heads compensate for the compression if thats the issue ?
I'm confused. I think I've answered your question twice, maybe three times.
Sorry just a little brain dead here with so many answers, thanks again.
OK so you have a fairly consistent 180/185 psi after 4 bumps on the Compression Tester
* do you know what Cam is in the Engine ?
* Do you know what Head Casting # is currently on the Engine ? This one is important if you can get the number off the Head
* do you know what Head Gasket is currently being used on the above Heads ?
Hang in there... try to answer a few more questions and we can give you some good advice ok ?
And for clarification,
you can run more than 150 psi.... I was only indicating 150 psi as very "safe" for a FULL TIMING Curve(36* Total) at sea level with the HUGE .090" to .100" Quench.
Quote from: Challenger340 on March 03, 2020, 05:11:15 PM
OK so you have a fairly consistent 180/185 psi after 4 bumps on the Compression Tester
* do you know what Cam is in the Engine ?
* Do you know what Head Casting # is currently on the Engine ? This one is important if you can get the number off the Head
* do you know what Head Gasket is currently being used on the above Heads ?
Hang in there... try to answer a few more questions and we can give you some good advice ok ?
And for clarification,
you can run more than 150 psi.... I was only indicating 150 psi as very "safe" for a FULL TIMING Curve(36* Total) at sea level with the HUGE .090" to .100" Quench.
He had stated prior its an xe284h10 with no clue on head gaskets as engine came assembled, hasnt posted heads.
Im still waiting on why the question about changing compression has come up. In another thread it has been stated that the orginal owner ran it on pump gas and the way i understand it, it has not been run since he has purchased it? What is the actual problem with the engine at this point in time. So far it sounds like an old school 10:1 mill with a mild cam.
Agreed on quench clarification.
I guess I better understand the OP's confusion.
To the guys asking all of the questions; why? The OP wants to know if and how he can run pump gas.
First - Even with the limited imperfect information we have, does anyone really think that he cannot get this thing to run on pump gas with a aluminum heads? Yes or no? The question is simply "can he do it", not exactly what 20 part he must have.
Second - There is no information he can get now that will allow us to know if he can get this motor to work with his iron heads. Although the evidence suggest to me no way. No matter what head casting number, you still won't have enough information. (Have the heads been milled? has the block been decked, what head gasket thickness...?)
So here is the logical order of things at this point:
Step 1) Because he can get to pump gas operation with aluminum heads, we know the worst case solution. Therefore remove the heads.
Step 2) Measure the head, compression distance, and gasket thickness.
Step 3) With that accurate information, decide if you can make these heads work
Step 4) If not, with this same information, evaluate which aluminum head, and which gasket will be best for him
Step 5) Put it back together and go have fun.
There are other options, like mill the piston dome, or put in a stupid large cam. But pulling apart the motor to mill these pistons is dumb money considering the result, and a big azz cam is unlikely the OP cup of tea, or he certainly has not indicated it. Then we can talk about gears and torque converters.
Redid the TDC timing check and the line on the damper was almost 2 in. before TDC 0 mark. I kept retarding the timing to where it starts OK with the compression and can't see where the line is.
The POS battery was the starting problem. With a new battery it fired up in about 5 or 6 seconds !!!
Any reason why the timing line is so far advanced ? Thanks.
Quote from: Highbanked Hauler on March 03, 2020, 08:02:47 PM
Redid the TDC timing check and the line on the damper was almost 2 in. before TDC 0 mark. I kept retarding the timing to where it starts OK with the compression and can't see where the line is.
The POS battery was the starting problem. With a new battery it fired up in about 5 or 6 seconds !!!
Any reason why the timing line is so far advanced ? Thanks.
updated
Quote from: Highbanked Hauler on March 07, 2020, 11:36:56 AM
Quote from: Highbanked Hauler on March 03, 2020, 08:02:47 PM
Redid the TDC timing check and the line on the damper was almost 2 in. before TDC 0 mark. I kept retarding the timing to where it starts OK with the compression and can't see where the line is.
The POS battery was the starting problem. With a new battery it fired up in about 5 or 6 seconds !!!
Any reason why the timing line is so far advanced ? Thanks.
updated
Im not following the procedure you used here, but i think you are describing a spun balancer?
With a ratchet rolled the engine over till the valves closed on No. 1 and threaded in a tdc stop and turned the motor till the piston hit the stop. Dist. rotor was on the no. one wire.
What can be done with a spun balancer ?
Nothing, you replace it. The rubber is shot and allowed it to turn on the shaft
There are services that will replace the rubber ring.
https://damperdoctor.com/index.php?route=common/home
Only open 75% of the year....http://www.hbrepair.com/
There's others out there...