Best setup for low-midrange torque on a stock 2 bolt main L05 88 350, with stock trans and converter?

L31MaxExpress

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Shorter tires are even cheaper.
Going from the 32" tall P305/50R20s on stock Ram 20s that weighed 84 lbs per corner to 17" front runners with much lighter 245s and 26.5" tall drag radials knocked nearly 1/2 second off the 1/8 mile of my Ram when it had 3.55s. The same wheels and a slightly taller 28" tall drag radial still knocked 3-4 tenths off with 4.56 gears. Looked absolutely rediculous on 26.5" drag radials but it was quickish. We also used a short belt to drive only the water pump and alternator. The radials were 275/40R17s.

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The_Family_Tahoe

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Going from the 32" tall P305/50R20s on stock Ram 20s that weighed 84 lbs per corner to 17" front runners with much lighter 245s and 26.5" tall drag radials knocked nearly 1/2 second off the 1/8 mile of my Ram when it had 3.55s. The same wheels and a slightly taller 28" tall drag radial still knocked 3-4 tenths off with 4.56 gears. Looked absolutely rediculous on 26.5" drag radials but it was quickish. We also used a short belt to drive only the water pump and alternator. The radials were 275/40R17s.

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1\2 a second off the 1\8th ! I've always suspected a heavy wheel and tire may soak up some power, and these are real world results. Thank you for sharing.
As an anecdotal data point I saw a YouTube clip a year or more ago where a truck went from 20" wheels and tires on the chassis dyno to a 17" or 15" wheel with a drag radial and picked up 90 hp due to the unsprung weight savings. It makes sense though, imagine playing tether ball with an 84 pound tether ball vs a 40 pounder.
 

L31MaxExpress

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1\2 a second off the 1\8th ! I've always suspected a heavy wheel and tire may soak up some power, and these are real world results. Thank you for sharing.
As an anecdotal data point I saw a YouTube clip a year or more ago where a truck went from 20" wheels and tires on the chassis dyno to a 17" or 15" wheel with a drag radial and picked up 90 hp due to the unsprung weight savings. It makes sense though, imagine playing tether ball with an 84 pound tether ball vs a 40 pounder.
Unsprung weight effects handling more than acceleration. Its the rotational mass of the heavier wheels and tires that hurt the acceleration. I do not know of an exact formula but the effect on ET is about 4x. Lose 100 lbs off the wheels and tires and the effect is similar to losing 400 lbs elsewhere. Rear disc conversion is on my list of things to do on the van for this reason. It would be nice to lose the inertia of ~60 lbs of rotating weight. My rear drums are 63 lbs each on the van. A GMT800 3500 srw rotor is just over 30 lbs each.
 
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Erik the Awful

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I have 255/45-18s and 275/40-18s on some stylish, but heavy 5-spokes on my '06 Mustang for street driving. When autocrossing, I have a hard time getting it into its power band. I swapped on a set of 245/40-17 RE-11s onto the stock rims and ran those for a couple years. They were a full two inches shorter than the stock tire, meaning that with already being lowered 1.5", my Mustang sat lower than anything else out there. Even though the cross section was a full inch narrower in back, they stuck better. Best yet, I was always in my power band. Win, win, win. I was embarrassing Miatas. I still couldn't hang with that '18 GT350 though, I need another 225 hp.
 

Frank Enstein

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I had an 84 GMC van with a 77R4 and 3.08 gears. That thing would downshift if you looked at a hill.
Start at the back bumper and move forward from there. Having 4.10 gears isn't bad at all. In overdrive they become 2.87 gears and lock the converter and they feel like 2.61:1 gears. If that level of performance makes you happy you're done. If not, do a Cat-Back exhaust system. Want more? Headers. Removing the silencer in the intake tube can help and it's free. A Hypertech Power Charger. They are discontinued but they are out there. An adjustable fuel pressure regulator (JET-61510 @ Summit Racing) will allow you to tune for best performance after each mod. Synthetic fluids will reduce parasitic loss.
I like to remove the external restrictions before going inside the engine.
 

GrimsterGMC

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Gearing is a very much overlooked part of a whole system. It's okay to know that you are producing X amount of power but is it going to be there when you need it. Everybodys driving style and requirements are different so re-gearing to suit is what ties the whole performance package together.
 

L31MaxExpress

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I had an 84 GMC van with a 77R4 and 3.08 gears. That thing would downshift if you looked at a hill.
Start at the back bumper and move forward from there. Having 4.10 gears isn't bad at all. In overdrive they become 2.87 gears and lock the converter and they feel like 2.61:1 gears. If that level of performance makes you happy you're done. If not, do a Cat-Back exhaust system. Want more? Headers. Removing the silencer in the intake tube can help and it's free. A Hypertech Power Charger. They are discontinued but they are out there. An adjustable fuel pressure regulator (JET-61510 @ Summit Racing) will allow you to tune for best performance after each mod. Synthetic fluids will reduce parasitic loss.
I like to remove the external restrictions before going inside the engine.
I am right there with you. I still have an 83 G20. It was born with a 305/700r4 and 3.08s. Stock it too would downshift looking at a hill. At the time I drove long distances at highway speeds more than I did around town. I did external engine stuff first. Mine had catless duals and tubular manifolds with dual smog pumps. First thing that left was the factory intake manifold. I put a Performer RPM Q-Jet manifold, recalibrated the Q-Jet and recurved the HEI. The air pumps took ~3-5 hp each and were stolen off the van one night along with the air tubes that made changing plugs a near impossible chore. I put a X-pipe in the pipes where they ran together approximately under the driverside mid row seat. Later found a set of nearly new Thorley tri-ys on Ebay and put them on. At 150K, I put a cam in the 305 and had the 601 heads worked. Drove it another 50K before it spun a rod bearing. I went through a TBI 350 short block and put the 305 top end on it. That engine ran 100K before snapping the crank in half. I rebuilt the 305 0.040 over, put 081 TPI heads on it and put TBI on it. Then popped the head gaskets on the 305. I put a crate TBI 350 into it. Eventually that 350 got a bigger cam and ported Vortecs with a single plane. I also had a weiand 177 blower and then TPI on it. The body of that van has ~460K on it and it has had an 8.1 for several years although I currently do not have it tagged and it needs a front end rebuild. Its on the back burner and will get a SAS 4x4 conversion befor long.
 
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