Hi, I'm new to all this but I'm wanting and trying to learn. I have a 92 RS Camaro that we recently swapped engines in (nothing at all wrong with the 305, I just caught the bug and wanted more)... I bought a 383 stroker motor from a guy and had my husband's cousin (mechanic) put it in for me. We originally wanted to keep fuel injection but it wouldn't idle right so we went with carb. It has a Holley 600 or 650 four barrel I can't recall now which one it is (we had a 750 on it and it flooded all the time), 292 magnum cam (already had one in it, it had 2 worn out lobes so we replaced it with the same new cam), got an older model distributor. We had 373 gears put in the stock rearend. We put a shift kit in the stock 700r4 trans and also have replaced the torque converter. I have been told I should put a 9 inch torque converter in it and it would help... because the torque converter we have on it now is even bigger than the stock converter. My problem is... on take off, it sucks... top end the thing will fly but on take off it will barely bark a tire (and that's *with* the shift kit)... it seems like it still floods out a little on take off and then once it gets going it will stand up and just absolutely mortally fly. Any suggestions? Thanks.

Katy

 

Well assuming that there aren't any tuning issues, a cam that big is going to want a whole lot more stall than a stock torque converter has. When you step on the gas, you want the converter to let the engine flash up into its powerband right away without any load, which would probably be somewhere around 3000 RPM with that cam. The stock converter will only let it go up to about 1400 RPM or so, where your engine isn't making any power yet.

What are the specs on the new converter you put in?

 

with a 383 you would probably want a 700 or so carb, go with edelbrock or demon.

 

Choice of carb isn't really the problem here, though.

 

i know, it sounds like the cam, im just giving her advice.

 

A bigger carb would only make her current problems worse.

Smaller, higher stall torque converter - that's what's needed.

 

Well, my parents got the torque converter a long time ago so I don't remember very well... but I know that it's bigger in diameter than the stock one we took out and very heavy. I think it's around a 2500 stall (but that's just a guess.)

Katy

 

Bigger than stock would be unusual.

 

I just wonder if maybe we have the wrong stall in it. I'm wanting to get around a 9 or 10 inch one with about 3000 to 3500 stall... think that would help?

Katy

 

That would be about right.

 

Yes, in this case, smaller is better. 3000-3500 would be about right, and then you could address the next item, the too-small carb.

 

If the motor previously rounded off a few cam lobes, the rest of the motor can't be in good shape. I've never rounded lobes off a cam and not had the bearing clearances go to crap. Just keep that in mind as you trouble shoot this thing.

 

Swap to a 3500-ish stall converter and you'd be much happier. The reason it feels so lazy from low speed or from a stand still is because the larger converter has a really low stall speed.. something around 1200-1400rpm. At that speed, the engine isn't making any useful power yet with that huge cam. Once it gets into its powerband, then it will start making alot more power, which is why the top end feels so strong. A higher stall converter will let the engine stay in its useable powerband when accelerating, which is what you want.

Also, if you do decide to use a larger carb, I would HIGHLY reccomend a Holley 3310. Its a 750cfm 4bbl, vacuum secondaries, dual feed carb. I have one on my 350, and I love this thing. Never once had a problem with it, even being 40 years old like it is. Gets pretty good gas mileage, really improved throttle response over my old Qjet, and it made my 350 run exceptionally smooth. Tuning is a snap, and it never seems to need any attention. Its great!

Good luck!

 

Even though the torque converter is mostlikely the problem you might want to check the accelarator pump in the carb.

 

My dad got a bright idea a while back and decided the valves needed adjusting... the two valves that he tightened, matched up with the lobes on the cam that got worn off. Lol.

Katy

 

Ding Ding Ding Hows you gas mileage if you dont mind me interupting the thread?

 

I, on the other hand, would highly recommend against that carb. All of the benefits mentioned (except the 40 year old part) can be obtained with the proper carb for the job, a 750 CFM double pumper mechanical secondary carb.

 

Gas mileage is actually pretty good... but I don't really know for sure, I just run it til it runs low and then fill it up. lol. I don't pay attention like I should. It was horrible when we had the stock gears in the rearend, but since we got the 373s it's been better.

Katy

 

I wouldn't disagree with the 750 DP being a great carb for that motor, but for day to day driveability, would a VS carb not be a better choice for an automatic car? A double pumper would definitely have a bit of an edge, performance wise, for sure... but for just easy of use on the street, I would think a VS would be a bit better?

 

Nope, not at all. For daily driving, you don't engage the secondaries, so it's no different from that standpoint from driving a VS carb. On the other hand, if you do some "on-ramp T&T", when backing off at the speed limit, the DP will back off when your foot tells it to, but the VS will stay open until the spring can overcome the diaphragm and drop in signal vacuum. I much prefer the action of the DP in that situation over the VS.