i have a stock lo3 and 700r4 tranny and a stock non-posi rearend. what kind of 1/4 mile times should i expect if i shift slap-stick style? how about if i add and open element, headers(1 5/8" primaries/3"collector) 3 ypipe, 3" cat" 3 in catback;tbi performer rpm intake manifold. 4th gen 3.23 or 3.42 posi rearend; and a lt1 cam (tunin also of course) hopefully mid to low 14's

 

It really depends on how your stocker is doing. Some run strong, some run weak. How it has lived its life really makes the difference. Either way though, I wouldn't expect more than 15.5 stock and that's being generous.

With those mods listed, mid 14's maybe 14.3 if you're lucky.

And lastly, don't "slap-stick" it. You cannot shift faster than your automatic unless the tq convertor is slipping or something . Just put it in D instead of OD and power brake it.

 

Or unless your trans has a shift improver kit and you know the torque peak of your engine ...

 

My 89 RS with 174,000 miles on it, stock engine trans and 2.73 rear ran 16.07 at 84 mph. still waiting to run after i installed my exhaust and gears. I put the trans in D the first run and got 16.20, and manually shifted it the 2nd and third run to get 16.07. don't bother shifting yourself unless your trans shifts at 4k at WOT like mine lol...i manually shifted at 5k and got alittle better time.

 

iirc back when my car was stock i started losing power at around 4500-4700rpm's, thats when i would slap shift it. but by the time i let it spin to 5k it started falling on its face. so i modified my TB and bolted it onto a 350 vortec-that seemed to help lol

 

Mine is pretty stock, just bolt on's 15.35's @ around 88, 89 MPH....I think I was shifting way to hi, as I was leaving both 1st, and 2nd around 5500 RPM...Am going to try short shifting next time..

 

gallileo-that sounds pretty high for a stocker. your right-shorter shifts should help-the 305 induction does pretty good for low end but falls on its face pretty early

 

Yep gonna go friday, and try to bust the 14's...Got new plugs, and wires to put on, have removed the AIR pump, gonna try to leave the line different, and shift around 5000...I would really s**t if I hit the 14's.If not tho, have headers, and maybe a 3.42 gear...............

 

wow haven't been on here in a long time.

I don't know if this is correct(haven't indulged myself in tbi info like I used to)
but although tbi's tend to feel gutless when the RPM's climb, not allowing the motor to rev properly will place the car in crappy RPM's in the next gear.

When I was doing research I noticed that the fastest 1/4's people revved higher than what felt right

 

That is especially true with the 700r4 and crappy rear gearing. With the stockish L05 in the Van, it was fastest with the 700r4 shifting at 5,000, despite the fact that the engine ran out of steam at 4,500. Shifting at 5,000 instead of 4,000, brought the recovery RPM in 2nd after the shift from 2,500 up to 2,000 giving a HUGE difference in acceleration.

I ran a 16.7 @ 83 with the stock HD L05 crate engine, bolt-ons, a Yank 2,600 rpm converter, 3.73 gears, and P295/50/R17s, with a 5,300 lbs fullsize Van.



FWIW,

IMO, GM really struck out on the TBI engines from what they should have rolled down the factory with.

I recently built and tuned this combination for a square body B-car

9.5:1 350 (4 bolt main roller cam shortblock from a 1995 fullsize van, rebuilt to factory)
463 Aluminum castings (ZZ4 heads)
GM L98 roller camshaft (773, factory van cam) (202/206 @ .050, .403/.415, 115 LSA)
Van/Truck intake manifold (higher rise than what came in the F-cars or B-cars)
The smallblock TBI unit should have had the same modifications as the big block unit, from the factory
B-car LT1 exhaust manifolds and dual cat exhuast system
Low-restriction exhaust
1995 G20 Van 4L60E with stock 2,000 RPM converter (5,000 RPM WOT shifts)
2.56 Peg-leg rear with P225/70/R15 tires
A prom that actually had some attempt to it (late model 427 PCM from the 1995 G20 Van).

Ran a 15.41 @ 90.23 in the 1/4 with a 2.36s 60' time. 10.53 @ 72.34 in the 1/8.

Gets 24 MPG highway and 18 mpg city

Approximately
250 HP @ 4,500
360 TQ @ 3,000

 

Are those crank or RW numbers?

Also, those 1/4 mile numbers are in a Caprice with 2.56 gears? (just for clarification) If so, that's pretty impressive. Makes me wonder what I should run with mine.

 

My post get deleted? Anyhoo, I was saying that combo won't run low 14's in Phoenix, crappy air, less than amazing track. You'll need some SERIOUS weight reduction and suspension work. Mods, where'd my post go?