I was wondering how to get a stock 350 TPI with a 700R4 and 2.73 gears to run mid 13's. What will have to be done? (I'm looking at relatively inexpensive... but I have a few bucks to throw around!) Any info anyone can offer would be appreciated.... thanks!

 

A Vig 3000 converter
sticky tires
and maybe a bottle

 

Gears would help, The stall and tires are not a bad Idea either.

 

Both sound like good ideas... I have a 3.42 rear end gear set here I was thinking about using... any suggestions for engine mods?

 

All the free mods, like TB bypass, and maybe porting the plenum. All this is quick and inexpensive. Maybe want to add a shift kit to the 700r4.

Of course lighting up the car and some practice launching the car.

Exaust and headers, gear, tires, torque converter, shift kit, free mods, and porting plenum. These are all good Ideas.

 

It all sounds good to me, but I do have a question... What exactly is the TB bypass? I've heard of it before, but I don't know what it entails. I've also heard of "siameseing" the plenum and intake. Any opinions?

 

Your choke points:

2.73 gears are inadequate. Swap in that 3.42

A shift kit was said - cheap and beneficial.

TPI stock runners are also inadequate. You might look into some aftermarkets for a significantly wider powerband. It is important that you portmatch everything so you squeeze all the potential.

Everyone said free mods - Yes. Cut your airboxes, tune the bitch up, scrap some weight and relocate your battery to your hatch to improve weight distribution a bit.

Get a lower temp thermostat.

I believe you said you have a 3.42 gear set, so thats no bucks.
A shift kit is like 150.00.
Larger runners will run you a cool 300 or 400 bucks. Look for used ones on ebay to decrease the price a little.
Free mods are inexpensive at the most.
Lower temp thermo is like 20.00

 

Stall converter, cooler and shift kit, drag radials and the usual bolt ons got me mid 13s. Even managed 1.80 60fts with Eibach Pros, being at sea level in good air wont hurt either but its all about your 60fts...

 

Runners on a stock heads/cam motor are hardly worth the effort. I had 3.23's, but was able to run 13.00's w/ a small cam & drag radials. That was stock heads, and a mostly stock TPI. When I put the Accel runners on my car it didn't pick up much ET wise, I doubt it would have done much if I had a stock camshaft.

I can't agree more about a torque converter, but get a good one! Do all the easy & free things first before you dump tons of cash into the car. Right now you need to get a baseline and see how the car runs as is, then go from there. I've seen a few cars run into the 13's w/ 2.73 gears. If you are wanting to keep the 2.73's for lower cruise RPM on the free way - by all means keep them. Also, the DIY PROM board here on this site offers a wealth of info, I'm willing to bet that you could reap good gains with just a little chip tuning. I didn't have the benefit of that knowledge when I had my car running 13.00's.

 

The runners aren't going to make his car a hot rod, but they will widen the powerband so that there is more useable RPM. There quite a bunch of power potential locked up inside the restrictive factory TPI intake. Stock heads and cam will reap the benefits of unchoking the TPI. Not as much as a better cam/heads pair up but still benefits are there to be reaped.

 

Where are you getting all this? Have you actually put runners on a TPI car? Any timeslips? Dyno #'s, etc to back it up? Not to sound like a total a$$hole, but your last reply sounded like it came right out of an ad for runners. I have timeslips and SOTP experiences to back up what I'm saying. For what runners cost, it's money better spent towards a good converter.

 

Thanks for all the info guys, I'm finding it pretty useful.. can anyone recomend a good Converter? I'd much appreciate it.
I definitely plan to get the intake/plenum ported out in the near future (may as well do it while the engine's out). Does anyone know how many RPM's I would be changing by going to a 3.42 instead of a 2.73?

 

Precision Industires, Hughes, Art Carr. Stay away from TCI and B&M cheapies. I'm going to assume you are running stock height tires = 25.7 inches tall - w/ 2.73's @ 80 MPH = about 2000 RPM, w/ 3.42's = about 2500 RPM. HTH

 

Tell us more about the ride, what year, any mods, any time slips?
I will assume that you need to pick up car up almost a second in the quarter mile. Tune it up, new plugs, wires, cap, rotor, coil, and most important vacuum hoses. Do the free stuff, TB bypass, ported plem., adjustable FPR, make a flow director in the intake ducting, and if you have the air box that takes the round filter cut some holes in the housing. Then money time, convertor, convertor. Nothing else will give you near the gain per penny as a torque convertor. After you get the convertor you will need to make it work for you, tires and maybe some LCA's. Time to visit the PROM board, buy the stuff and learn it. As far as the aftermarket runners and bases save the money and buy a HSR. Cheeper than runners and a base and a hell of a lot more flow. Now your ready for a good cam that will work with the HSR, and running DEEP into the 13's.

 

Porting is a free modification and gets good horsepower. Port the plenum, runners, manifold, and heads. Cut open the air box, modify the MAF (if applicable), tb airfoil, torque converter, shift kit, gears, sticky tires, headers and exhaust, sfc's, tb bypass, and other free mods. You'll see mid 13's with no problem.

 

See my sig. A few more mods and some more weight removal and it will hit high 12's.

BTW, the E/T and dyno runs were with the stock iron exhaust manifolds and on the Yokohama A520's.

 

I wouldn't think it would be all that tough with a 350. I have a 305 and I ran 13.89. You can see my sig for the mods that I have done. I would definately put headers and exhaust on. That made the biggest difference in my car along with a tuneup.

 

I mean - I've already offered him what I consider sound advice for a TPI seeking mid 13's. Theres not much I can say to make you give me more credibility except for the fact that yes I do own a TPI 350 and that I stand by what I know. Oh yeah, not to be a dick or anything, of course...

 

Thanks for the fast replies everyone, I'm grateful :hail: ... I'll give you the run down on what I have here:

1990 Pontiac Firebird. Car was originally equipped with a 3.1L V6. I purchased a 350 TPI that came out of a '91 Z28 Camaro, and a 700R4 from a '92 Z28 Camaro. The engine uses the Speed density system, so no MAF to play with (don't know if that's a good thing or a bad thing). The car is currently undergoing the swap as we speak, and I'm hoping to have it running and on the road within the next two weeks, with some of these mods completed (at least a shift kit, and ported head, intake, plenum, etc.) I'm anxious to see how it runs myself... I'll have some pics to post soon. Here's the inside of it currently:

 

I have the headers on now. Just need to have the dual cats welded up. Since the streets are paved with rock salt and the weather has been below 32 degrees for the last 28 days, I am not in a hurry.

The main thing thing is to tweak what you have little by little and not just throw a bunch of parts at it and expect it to run 11's. I have owned the car for 9 years and just put headers on a month ago. Learn to know every quirk of the car and just change things in stages.

 

Here is a good place for torque converters. Alot of guys around here run them at the track and have good luck out of them.

they can build you what ever you want and also do work on them.

www.ptcrace.com

check them out. Good converters at reasonable prices.

 

anyone know where I can find a set of headers? Just wondering. I currently have a 2 inch stainless pipe running through the car for exhaust, with the cat removed... I'm thinking my existing Y pipe is a bit... well... restricting. Anyone know a good diameter pipe to run, that will offer good power gain, but still produce proper backpressure?

 

Personally, out of the 3 sets of shorties I tried on my old 350 LTR set up - I liked the Tri - Y's the best. They are really hard to come by, I almost regret selling mine. More than likely your best bet will be to buy a set of headers w/ the matching y-pipe... it takes out the guesswork.

 

300 or 400 bucks?! what planet r u from?! i got my new SLP runners for 180 new from summit

 

That's not a bad price.... Funny though I was looking through summit's new catalog yesterday and I didn't see anything. But I'll keep looking. I'm heading out to the retail store this coming saturday, Maybe I'll come back with a set!

 

summit has stopped selling SLP parts... there was a huge sale on all there stuff so they could get it out of the warehouse, and they had runners for cheap.... 180 cheap... there usualy 260 for slp... and they have plenty of meat to take out...

 

Do you know when summit stopped selling them?

 

Well I have seen em run bad ... good ....... check out IROCZONE.com there is a guy nick ... Ski that loves his 2.73 gears and is bent on hitting the 12's with them
check out there members page and look for mike Ski

He is well inbto the 13's ....but he does prom tuneing ( you will need it ) .

With the Speed density setup ......it is more sensitive to mods
Maf setup is a little more forgiveing . But if you plan on any horsepower ( I THINK the magic # was 325 hp) more then 325 you should go to a Speed Density setup .

****** THis info was from other posts on this board*******

So .... definately ask around ..... for I am no authority , I just figured I'd regurgitate some info shared here from respected members .

 

This is all sounding better and better. Does anyone know what a decent port job on the heads and intake will cost? I'm kind of worried about messing it up, seeing as I've never done it before. Also, who makes a good Shift Kit for a 700 R4?

 

get the trans-go kit. again, as stated earlier on this thread, avoid tci and b&m stuff. everyone sees this stuff available from summit, jegs etc. and assumes it must be fine...I've never had anything but bad luck in the past w/cheaper parts. take it from someone who has used all the cheap stuff before....

 

summit stopped selling slp parts im gunna say.... in late november/ early december... if u do a search in the aftermarket producto board for slp runners, im sure ull find the frenzy that went on when they put this big sale up.... one guy said there were like 15 left, and when i called 5 mins later to get a pair... gone.... all gone... they were for both 88 down and 89 up...

 

well i cant say for porting heads, but porting your intake is ez... dont pay somebody to do it.