too much stall i think ???? need input VIBRATION SOLVED.

[mally69]

Engine specs
440 .60 over
10.5-10.8 comp
Comp solid flat tappet can 294 dur, 525 lift
1.6 rocker ratio so lift is .555
TM-7 intake
Mighty demon 750 double pumper
4.10 gears.
Hooker 1 3/4 headers
440 source Stealth heads stock except I used upgraded locks and retainer

Current convertor is a TCI street fighter I believed it was to stall at 3000-3500. My problem is if I'm cruising in high gear lets say 50 mph and put down the throttle it seems like it doesn't wanna start biting hard until 4500 4800 rpms. Car launches and runs good but I'm thinking it's not correct for my build almost like i need a tad tighter convertor.  What's you guys input??

[c00nhunterjoe]

What gears are in it? If you have 3.23's and mash it in 3rd, then with the torque that engine puts down, it may tlas the converter around 4000. What does it flash to from a dig powerbraking it?

[mally69]

I have 4.10s just cruising 45-50 mph and land on it. It def goes up around 4800.

[c00nhunterjoe]

How tall are your tires and what does it flash to on takeoff?

[mally69]

275/60/15 I believe they are 28".  Flash as if holding in the brake till it breaks loose is prob 3_3500 I'll have to actually try it again to verify for sure

[c00nhunterjoe]

Ok, see if you can get the brakes to hold the car to see how high the converter will go. If your speedometer is accurate, then 45-50 should be around 2500 rpm actual cruise rpm,so if you take into account the engines torque at idle vs 2500, you can see why the stall changes from 3500 to 4800 from idle vs a 2500rpm roll.

[mally69]

I guess basically my concern is if all this is normal or if I need to looking for a better fit convertor for what I've got setup. I kinda felt that it was excessive but wanted more input from all u guys.

[c00nhunterjoe]

From the information given, it sounds normal. From this point, its more of what you want. It should be a good launching car, but if you are strictly a cruiser, then you might want a tighter converter.

[mally69]

Oh it def comes alive and launches instantly. Just wasn't sure if it that was normal  . Def not Into just cruising , 

[c00nhunterjoe]

If you are more of a track or stop light bandit, then i wouldnt change that converter. If it does see street cruising, might want to invest in a trans temp gauge, deeper pan, and respectable cooler to keep heat under control.

[mally69]

Yepper I got a b&m deep sump pan and a pretty large. Tranny cooler upfront and center. When I take it out I'm mostly harassing the newer cars so I def wanna make sure it's up to snuff hauling ass the best I can get it to

[c00nhunterjoe]

Sounds like its setup for the abuse. Got a temp gauge for the trans?

[firefighter3931]

Hi Mally....good to see you posting again 

Do an rpm check at speed ; let us know how much rpm's it's making at 60 mph and verify the tire size. That way we can calculate converter slippage. 

Converter efficiency can be all over the map....the more expensive converters are just more efficient and perform better. A Dynamic 9.5in unit would be just about perfect for a build like yours. I had one with my old 446 combo and loved it. 


Ron

[mally69]

Hey Ron thanks. I was hoping no one forgot about me I been very very busy the fast few yrs but now with a new house and garage built it's time to play chargers again.  512 in the 68 is next very soon.   But anyhow I'll def check all this tonight for ya and give you the details this evening hopefully we can get something figured out here

[mally69]

Also no temp gauge for the tranny. I used a laser temp checker I believe it was 100-125 °  if I remember correctly . But I'll check that again as well tonight

[mally69]

At 60 mph it's turning right at 2800, I have a 28 inch tall tire. , and I feel like a complete idiot, where I thought it was reving to 4800 was actually 3800 which is perfectly fine. I honestly have no idea how I thought it read 4800. Totally mixed that one up. but regardless the convertor is coming out. I have a bad vibration and the only thing it can be is that converter. I sat there tonight and as I rev the engine slowly you can feel it vibrate at a certain rpm. when I'm setting still and in neutral.  Also I have a full manual cheetah valve body I put the car in high gear  and was going 10 mph and matted the throttle it stalls at 3800-4000 rpm so that Part is fine. But my vibration is the bad part, so what Ur recommend ed convertor , I def don't want a TCI or BM.

[c00nhunterjoe]

At 60 mph it's turning right at 2800, I have a 28 inch tall tire. , and I feel like a complete idiot, where I thought it was reving to 4800 was actually 3800 which is perfectly fine. I honestly have no idea how I thought it read 4800. Totally mixed that one up. but regardless the convertor is coming out. I have a bad vibration and the only thing it can be is that converter. I sat there tonight and as I rev the engine slowly you can feel it vibrate at a certain rpm. when I'm setting still and in neutral.  Also I have a full manual cheetah valve body I put the car in high gear  and was going 10 mph and matted the throttle it stalls at 3800-4000 rpm so that Part is fine. But my vibration is the bad part, so what Ur recommend ed convertor , I def don't want a TCI or BM.

What balancer is on the engine. Are you sure the rubber didnt slip? Is your engine internal or external balance? You may need to remove/install the balance weight on the converter

[mally69]

I had an origional harmonic balancer on it , removed it and put a chrome 440source fluid balancer on it, when I changed the rod and main bearings.  Vibration is still the same before and after swapping those out. Rods and mains looked good but it was just routine maintenance. But this vibration I have been battling for a while even had my drive shaft rebalanced as well.  It's a steel crank 440 internal balanced.

[c00nhunterjoe]

Cant be a shaft if you said it does it sitting still and just revving the engine. Pop the shield off the trans and take a look at the converter and spin it over looking for external balance weights. Might be an easy fix and not have to pull the trans

[mally69]

I'll check .

[firefighter3931]

At 60 mph it's turning right at 2800, I have a 28 inch tall tire. , and I feel like a complete idiot, where I thought it was reving to 4800 was actually 3800 which is perfectly fine. I honestly have no idea how I thought it read 4800. Totally mixed that one up. but regardless the convertor is coming out. I have a bad vibration and the only thing it can be is that converter. I sat there tonight and as I rev the engine slowly you can feel it vibrate at a certain rpm. when I'm setting still and in neutral.  Also I have a full manual cheetah valve body I put the car in high gear  and was going 10 mph and matted the throttle it stalls at 3800-4000 rpm so that Part is fine. But my vibration is the bad part, so what Ur recommend ed convertor , I def don't want a TCI or BM.

The Converter is working fine ; 2800rpm @ 60mph is showing virtually zero converter slip 

The vibration is concerning though. I'm not totally convinced the converter is at fault 

Was the rotating assembly balanced (static & dynamic) by the machinist ?



Ron


Ps. If you're looking for a converter recommendation ; the Dynamic 9.5in street/strip converter is tough to beat for your build.

[mally69]

Yep rotating assembly was sent away to Pittsburgh crankshaft to be balanced. I would assume / hope it was balanced correctly.  It's a weird type of vibration. Starts at around 70 and gets worse and even worse the more throttle you give to it.. for example slowly get up to 70 mph you can feel it then start putting the balls to it it gets worse,  run it up to about 120 let off and let the engine slow u down u can really notice it, hit neutral as rpms die so does vibration,  this is what had me searching for things I'm at a stand still until I figure this out

[c00nhunterjoe]

Wait, so it only does it while driving? I thought you could duplicate it sitting still at given rpms? What you just described sounds more like a bent driveshaft, bad ujoints, or pinion angle.

[mally69]

Nope it'll do it setting still. When I first felt it I was driving. So after changing tranny mounts ujoints and had my drive shaft rebalanced it's still there, only I tried it while setting still. I just took it for a drive and here's the scoop. The vibration comes on so slightly at 3500 can barely feel it, if I  go to 4000 and hold it there the vibration isn't constant it comes and goes but it's pretty noticeable, and that is setting still in neutral,  And even worse when under load when driving . ..

[mally69]

Gonna swap out my converte. I'm going to call dynamic this week' to get a price on that 9.5 inch street/strip. That vibration I would assume is the convertor I'll poast back once I get the results if that was actually the problem.