crazydad42

I've got a new 383 built to about 525 hp and 500 torque. It's in an 82 with a built 700r4 and 3000 stall. My trans is built for the power but can the rest of the stock driveline handle the power? I will not be running slicks...only normal street tires on the road and not the track. New quality 3.73 in the rear. I know there are a lot of things I can do that will make the car launch and handle huge power but I'm only interested in it handing the 525 ponies I've got. Anyone running this power level have advice or can share experience?
Thanks!

TimAT

As long as the tires don't stick it should be ok. I'm still running the original rear in my 69- 4.11's and it's had the original 427/435, a crate L88, another crate LS7 and now a 496, all with the same Muncie. It's getting sloppy but it's never broken. (so far)

calwldlife

3.73 in the rear end?
is it still the aluminum carrier?
probably not?

i forget if those gears are avail for the aluminum?

i would go with big block u-joints and yolks,
beefy drive shaft
32 splines

mtmvette

Maybe a HD case cover. Shock loads are what usually break driveline parts. What the above posters recommend and - drive smart. you should be ok.

terry82

I also have a 1982 with the 700r4.i will not have the power that you have but what up grades to the 700r4 should I do when I rebuild the trans.

crazydad42

I just my trans to the shop and told them to build it for 500 torque. I know they put in a beast sunshell but I'm not sure what else they did. If I were to do it again. I'd just buy a whole trans from monster trans. They have a 700r4 rated for 650 hp and its a bargain. Less than what I paid for my build.

ajrothm

It'll be fine.


Dead hooking on slicks on a prepped track may be another story.

fitter

I also have a built 383, 447HP/462TQ in my '82. I swapped the earlier 700R4, but swapped it for a post 1986 model and had it built up.
Rear end is stock aluminum w/3.73's although I'm running Ridetech suspension on all 4 corners with a HD cast iron rear cover to accept the suspension components. All U-joints were replaced with HD Spicers. I drive the car hard and have never had any issues.
These cars are built better than most think. BTW I'm also running 275/60R15 Nitto drag radials on all 4 corners.

99 Black Bird TA

I think you will OK on street tires.

If the rear spindles haven't been greased recently, I would probably get that done.
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My 72 vette has a Dart 400 that on a chasis dyno made a mere 346whp & 404wtq thru a TH400 with a Yank 3200 stall. The engine builder insists that flywheel engine hp is around ~500 to 520hp and if the converter could be locked it would show on the dyno. I saw skeptical but 72 has pulled ~420whp cars.

My 72 has the original stock rear end with 3.08's and other guild changes its never been touched. All of the u joints have been replaced with heavy duty ones.

I agreed the driveline's are pretty solid on street tires at at least 525 hp.

ajrothm

I wouldn't be that skeptical about the power the builder claims, with the heavy driveline losses, plus parasitic losses from the accessories, possible loss from air flow under the hood etc...

FWIW, I dynoed my engine on the dyno and it made 657/670. Without the air hat (air turbine) and a little hotter it made 638/660.

In the car going through a T400 and 10" converter, it made 460 rwhp. That's 28% loss. I am spinning full accessories, and the car headers a only 1 7/8" vs 2" on the dyno...

460 rwhp doesn't sound like much does it....?

But 127 mph at 3700lbs is decent. My point is, chasis dyno numbers are useless.

Buccaneer

Is that at the rear or at the motor? At the rear on a stock 82 dana44 you "may" have issues after a few good launches with DRs. I just finished my new 383 a few days ago on the dyno and got 330/300 to the rear. I'm guessing maybe a 100 loss max, so 430 at the motor which for still running the CFI system is pretty good. I know there is still more power in that motor, but will have to upgrade the computer system again to get more granular with the tune, a 7747 only goes so far and I feel I have reached the limit. The motor was still carrying power out at 6200rpm and liking more fuel on the high end. I think mine should be fine with that power level and I'm running a beefed 700R4, yank 3200 9.5" TC and 3.31 gear. This dyno is a Dyno Dynamics which is known to be a heart breaker when it comes to numbers, it's more honest IMO, but not 100%. I bet if I through the car on a DynoJet, I may see another 10-15% increase which would be nice and closer than to what I was shooting for with my current system.

terry82

concrats on your new motor .great numbers on cross-fire.your 82 has to be fun to drive

crazydad42

Mine is at the crank not the wheels. You're getting awesome power with the crossfire. I scrapped mine.

Buccaneer

Oh, I think you will be fine then. Thanks.

Thanks Terry, it was running well even though it was a tad hot out. With another ECM I think I can pull another 25-35 out of it and have it run even nicer. There is no doubt it was hauling ***.

titanle

hmmm does that mean a 350 that might be pushing around 425-450hp could also cause problems? not to hijack but im having my engine top rebuilt and having a higher stall torque converter put in, the tranny is a 3spd TH400 I believe. Would I need to upgrade U joints or anything?

jb78L-82

Engine size has very little to do with potential drivetrain issues...it's all about the gross versus RWHP regardless of the engine size. Some good points have been made by multiply posters:

Yes, about 25-30% loss is correct and documented time after time going form Gross through the drivetrain to RWHP..no magic here or mystery despite what many folks will pretend to suggest. A 500 Gross HP 355/383 will put about 360-380 RWHP at the rear wheels.....You can very accurately predict what power goes to the Rear Wheels from Gross to RWHP. Same predicting how much Gross HP a particular engine will make knowing compression, heads on motor and cam specs..no mystery again, any more.

My L-82 355 with 425-450 Gross HP with a 4 speed and 3.70 gears has no issues with this power level since I do not drop the clutch at mid RPM's ever and always roll into the throttle...5 driving seasons now and no issue...255/45/17 ZR ultra high performance Summer only tires as well.

Strokemyaxe

titanle

Strokemyaxe

gkull

Could you please post every thing about your motor to get such high hp? I had to us a solid roller cam with afr 210 heads with a 7500 rpm rev limiter

as to 700r4 you need to buy a 800 hp unit before you can expect them to last

373 is marginal for a high rpm motor creating over 500 hp out of small ci like a 383. You really need 4.11. Because the gear spacing is bad

to make rear ends last you have to solid mount every thing and limit vertical wheel travel. With high rate spring. 420# is small with 500 plus hp
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