The Stovebolt Site Forums The Shop Area The HiPo Shop Can' spin tires

I have a 1977 Chevy step-side. originally a fleetside. the enigine was a 305 trans with 350 auto. stock trans would have been a 400. must have been switched at some point for a 350. Engine went south and I decided to make it a project and get a stepside bed and get a new engine.
Bought a 1978 corvette motor off a neighbor and had it rebuilt. 350 4 bolt main.
truck runs great but hit the gas and it just doesnt take off, tires wont spin,with not much weight on the rear you would think it would light up the tires. Once I hit second gear it takes off like a scolded dog and hit third gear forget it its gone and hold on.

What gives any suggestions??
Paul

What tire size and what gears do you have?

Not spinning tires is a good thing, however frustrating it may be.

How did it run before the engine swap? The same, worse or better taking off?

ran like crap the old engine was worn out. Not sure gear size How do I check??

Tires are 255/70/15

A 78 Vette motor was only 185 HP (L48) version
the L82 was only 220HP......

So , I wouldn't worry about not spinning the tires ....
Sounds like it's dong it's job just fine on your truck gearing and tires.

mike

when engine was rebuilt, differnet heads new trw forged pistons and a new cam. engine shop sais it should have at least 300 HP.

A 350 is not a big block. It's a mouse motor. It will spin on wet pavement. A 4:11 posi might work. I assume you mean can't spin in your heading.

Is the trans shifting to soon? does it seem boggy? perhaps its just a trans/rear end compatibility issue.

Boggy is a good term on take off, doesnt change early. How can I check for trans rear compatibility??

Thanks

That sounds to me like you hit that flatspot on your carburetor(Holly?), when it needs the accelerator pump to come on. I'd tweek with that ajustment.

check with a timing light to see if the advance is increasing as you rev it up.

TPI will cure a sputter.>TPI

What are your rear gears? 300 HP in a fairly heavy truck isn't a whole pile.

I had a 76 Chevy full size pickup that would spin the tires on dry pavement. Had a 350 with TH350 automatic. Everything was stock on it.

So yours should do better than it appears to be doing. 300hp even in that truck would get it moving quite well. May not be big block, but sounds like it should do better than it is.

I agree that it sounds like carburetor is not delivering the fuel it needs at low speed. Once into the high speed circuits they sound like they are working. The ignition timing could be off too.

First of all in drag racing they strive to NOT have the tires spin. No spin means good transfer of torque and power to the pavement. So spinning tires is just to look cute, impress the girls etc.
Causes other than what others have said about engine, it could be a torque converter problem or slippage in the transmission too. A slipping stator clutch will cause it to act like a fluid coupling rather than a torque converter, and what you describe is how it would act and feel.
Oh and if the tires stuck super good, no one would even attempt a burn out at the drag strip they wouldn't need to, ie heat em up.

If it falls on its face when you stomp on it check the vac advance on the dizzy. May not have enough vac to move it quick enough. Had that problem on my ZZ4 and it was an easy fix.

I am installing a new intake this weekend and a new distributor. bought the intake used and has some block off plates on it maybe thats my vacuum leak was an egr intake and I dont need that. distributor is stock 1977 so I got a new one from summit.
new intake is edelbrock proformer 2101, carb edelbrock 1806 and distributor is summit racing. if that doesnt fix it I am going to start looking at the trans and rear set up. I like 350 small blocks easy to work on and Nascar ran the mouse motor 350's for a long time and they seemed to go down the road at a decent speed.

Any body have preferences on gasket sealer? installing an intake gasket tomorrow> chevy 350

Any body have preferences on gasket sealer? installing an intake gasket tomorrow> chevy 350

I'll just kiss the outside of the water passages with some silicone. Both sides. I use Gasgacinch on the head and the gasket to hold it in place. I usually apply around the intake ports. I'll dab a little silicone under the front and rear corners before laying the gasket on the head. Then I'll put a 3/8" bead of silicone on the front and rear block surface. I do not use the provided rubber gasket as they always leak. I'll place the intake and snug on pattern. Then I'll torque on pattern, then check torque one more time. I usually leave the front and rear silicone squeeze out. If you are going for a cleaner look, you can use a razor to clean up the silicone after it sets up.

My guess is gearing or clutch slippage.

A built 350 should spin the tires on dry pavement no problem. Especially in a pickup. Heck, my 216 will spin em on dusty or wet pavement without the bed wood and strips and my AWD Volvo with 325/354 will spin all four tires w/ traction control off. A first gear scratch w 300hp even at the crank should just be a matter of dumping the clutch.

yep

TIRES NOW SPINNING!!! Thanks for all the advice trucks runs great now, new intake and distributor all new gaskets

UPDATE, I also found out had vacuum lines crossed coming from carb to trns, one vacuum one no vacuum when at idle switched them and nice black stripes up the road.