Here is what I have. 91 RS with an LT1, 6 speed and 3.42 gears.
SLP 1 3/4" headers and y pipe,
3" mandrel exhaust with 80 series Flow,
Crane gold 1.6 rrs,
Moroso CAI,
and CSI H20 pump. Everything else is stock.

I was wondering what a Granatelli MAF, underdrive pulleys, long tube headers and a timing increase would give me.

My best so far has been a 13.12@112 on motor. That is with a 2.1 60' and some false knock pulling some timing in the 1/8.
The rrs alone gave me 4 mph in the 1/4.

Any guesses? I am interested the most in the MAF. A guy down the road from me has a new one in the box he wants to sell.

Thanks, Mike.

 

It will give you very little if any. Your ET is good but your 60ft needs improvement. Get yourself a set of sticky tires, you'll be very happy.

 

The Granatelli MAF and underdrive pulleys are a waste of money. I didn't see any improvement at all. The Granatelli MAF will make you run too lean. I would change to a 160 thermostat and reprogram the computer to turn the fan on sooner. Also get a LT4 knock module. It will eliminate the false knock given off by the headers and rockers. Long tube headers will give you a little. I picked up .4 going from stock manifolds to FLP's. Since you already have SPL headers you may pick up .1 to .15. I agree with sssalah that you need to improve your 60'. A reduction of .1 in your 60' will reduce ET by 1.5. A 1.80 60' should put you in the 12.60's. Get some stickey tires. Please be aware that the stock 10 bolt's are weak. It may not survive hard launches on stickey tires.

 

I may be able to test the MAF out for free and if no substantial gains are had, tell him to keep it.

I already desensitized my knock sensor so I may do a little more. A bit of race gas first to make sure it is false.

I have a 160 and had the car running about 180 at the hottest on a hot day. I have since put the stock thermo in because of the winter. I have Tunercat so I had changed the fan settings to match the thermo.

Believe it or not, I have Nitto d/rs. I lowered the car and although it looks good to me, it's lack of hooking irritates me. Especially when I was cutting 2.0s with 245/50/16 BFG radial TAs before. I have an IRS Terminator torque arm but I still need to raise it back up a bit.

 

Very impressed w/ those times for the mods...3rd gens are a bit lighter...Id say the pulleys will give you a tenth and the LT Headers will help ya big time, DONT WASTE your money on that granatelli pos, surprised that man can still legally sell that, been years and hes still tryin to push that thing...GOOD LUCK

 

I know they probably on average are lighter, but when my car was stock with the 305, it weighed 3500 lbs with a full tank of gas and without me in it.

 

Hmm maybe not, that was just some of the 3rd gen boys excuses of why there were better then 4th gens.....personally l cant stand 3rds, but whatever floats your boat

 

The short time improvement will get you going good.
The change over to Longtubes will really help you out, I'd say 1 to 2 tenths gain from that alone, you'll probably see a MPH increase with the underdrive pullies but very little E.T. gain. The MAF is up to speculation , some have seen gains others have seen nothing. Since you have tunercat I would port my stock one and adjust your tables. Youd probably see more gain than the Granitelli.

 

forget the MAF.....stay away from that. The underdrive pulleys are a good mod. best bang for the buck I have ever done. (bought a used one for 40 bucks) Really woke up the motor and throttle response. with the pulley and a one inch hole in my exhaust right before the axle i picked up 5 tenths

 

MBonz28 made a statement "with the pulley and a 1 inch hole in my exhaust right before the axle I picked up .5 tenths". Whats up with the 1 inch hole in his exhaust? Is this some sort of 'free mod'? or an exhaust leak? Bill...

 

....I also asked the above question {r/e 1 inch. hole in exhaust} over at the LT1 forem due to higher volume and the fact that the question wouldn't be 'hidden' inside of another thread.... Bill......

 

I am guessing that it was just a rusted out spot in the exhaust.

 

That is an extremely high mph for just a bolton lt1. I don't think I've even seen mph that high without a cam...especially full weight. Now back to your question; I've heard enough negative stuff about the aftermarket MAFs to leave them alone. Pulleys do work, but without the overdrive alternator pulley, I lost a couple batteries over the course of a couple years.

 

I know about the mph. I was running 104 with a bad plug wire and just the headers, and CAI. Then after the water pump and new opti and wires, it went to 107.x. After the rrs(and I lowered it for aerodynamics), I see 111-112 mph trap speeds. What is even more interesting is that the 1/8 speed has been around 85 the whole time. I feel it will be higher as soon as I get rid of the knock retard. It happens on the 1-2 and 2-3 shift so after I get into third, I have a good run which is why I think the 1/8 mph is low compared to the 1/4. Going from 85 to 112 feels pretty good though

Maybe I can get a couple more mph out of it and see good numbers for a bolt on LT1 that can wax some of those cocky LS1 owners.

 

as for the 1 inch hole. I had a small dent right where the exhaust began to turn up before the axle. I decided one night before hitting the track to drill it out with a 1 inch hole saw. It was like a mini cut out. It didnt make it much louder at all. Im sure it gave me some power cause i cant see a pulley netting me 5 tenths. I painted it with some rustolem and when i removed the exhaust 6 months later it had not rusted at all!