I own a 92 GTA with a 350 TPI with 53,000 miles. The car was completely stock right down to the paper air filter and I ran a 14.62 @ 94.32 mph with a 2.211 60 ft. A week later I got a 2.158 60 ft on street tires so my car would have easily run a 14.5x bone stock at an elevation of 1700 ft.

I took the car to the track again at the end of May and ran a 14.43 @ 94.65 mph with a 2.045 60 ft with slight wheel spin. The only difference was I was running ET Street Radials and I removed the back seat (I was detailing the car). I was running 26 psi in the back tires which I subsequently found out is more than what the M/T tires like, so I will be dropping the tire pressure down to 18 psi and shooting for a 14.3x on June 23rd.

 

25, 20, and 18psi in my ET Streets didn't change the 60's. When I dropped to 15 I gained a 10th, when I went to 12 I gained 2 more tenths. This was on a track with some shoddy prep but the car absolutly loves 12 PSI. I just backed this up by running them with 18 Psi at a race for my qualifier, slow 60 foot moderatly good 1/8th mile run. Took them down to 12 for the event and I got badass 60's and ultimately won.

 

1991CamaroRslow. Couple of questions. Are you running the radials or the standard ET Streets? Also with the lower air pressure did your MPH also drop? Sometimes that is the case.

 

Standard old school ET Street, not the radial tire. We've done some messing with the ET Street Radials and find they also like low pressure. We've ran a set of them at around 12psi on the street and it did awesome on a Mustang. My MPH was at 97 with me driving, before that I'de hit anywhere from 94 to 99. It did a 100mph run with my friend driving who's lighter than me on the ET Streets so really it didn't slow me down much.

 

Thanks. Looks like I will have to lower the tire pressure some more. Sorry to get off topic.

 

Best street tire run....13.88 at 97 or so.

stock L98 with gutted air intake, hooker shorties and 3inch catback with stock cat. 2800 stall with 3.27s.


Best slick run
Same stock L98 with just shorty headers, 3inch custom catback, 3.42 gears and 2800 stall.
13.63 at 96.7

not bad for just exhaust for power, and a converter

 

New best is 12.41 @ 111.77 on a 100 shot and ET streets, other mods are in sig. Still stock heads, cam, and untouched TPI stuff. With some more seat time, and a 150 shot I think I can touch the 11's on the right day.

 

careful with 150 shot though bro. i used to use that much off the line, man it went gooood!! how ever after my nitrous burp i tend to use my 150 shot just before the 60' timing box. is there anyone running quicker than an 11.7 on here?

 

I used to spray my 150 shot out of the hole every time I took it to the track we're talking hundreds of pounds worth of nitrous through my car on that shot. It does make a difference yours being a stick car, the stall took alot of the worry out of it for me, it would flash higher with the initial hit of nitrous and being a 3k stall it took alot of the worry out of it for me. I'm lazy and still haven't got my car track ready for a drive to Edgewater but I should be in the 11's, I think 11.7 or better is possible with the planned mods plus it being gutted interior wise now.

 

Havent been to a 1/4 mile track yet,but 1/8 times are 8.78,1.9x 60`@78 mph.From what I could figure with help of wallace raceing.com calculators is 13.7xx or so.Mods in sig.street tires@18 psi,stock stall and stock 2.73`s,no porting on stock tpi,tb or heads(yet),Was told it had a stage1 transgo.NEED BETTER HEADERS,saving for some LT`s.Rest of mods in sig.Oh yeah accidently did that time with vacume disconnected from afpr,not sure if that hurt it,didnt realize it till I got home.I think I might even be a little better than 13.7x in the 1 1/4.I`ll find out soon.Also this was only my 2nd time at a track ever and maybe my 15th run ever.Still learning

 

See my sig for et's and my best 60' is 1.94 Toooo many mods to list so if you dont mind click here for a complete detail of all mods. Oh and I ran a 14.07 @ 98.3 mph on BFG Comp TA KDW's with 32 psi in the tires and 50 psi fp and 12+ deg of timing. No chassis adjustments yet.

 

I'll add my slowness... 14.434 @ 97.20 MPH, 2.26 60'.

1991 Z28, 135K+ miles. Mods: $8D BIN, 3.73's, MSD 6A & coil, gutted air boxes, K&N filters, !smog pump, gutted cats, BBK 52mm TB, TPIS wires. All else is stock including the muffler. I bought the car as is, with the exception of gutting the cats and removing the smog pump. I only did that because one of the cats decided to come apart.

The car has cheap 245/50-16 street radials, 100% stock suspension. DA was around 3000' the night I ran it @ OSW.

Planned mods: swap back to 3.23's, and drag radials for the track.

I'm thinking with those mods and cool air this Dec./Jan. - it "should" run 13.90's.

 

Just an update, I added a Magnaflow/SLP 2OTL muffler/tailpipes after one of the baffles in my factory muffler fell apart. I also added BMR chrome moly LCA's, and some cheap eBay bolt on relo brackets. Lastly, well-worn 255/50-16 BFG DR's on my stock wheels - and removed the front sway bar.

Similar DA to the last time I ran, 14.225 @ 96.89 MPH, 2.067 sixty foot. The car decided to shift @ 6000-6100 vs. the normal 5200-5400. I guess the increased tire height threw it off that bad. Currently 139K+ miles and counting. With the suspension mods & 3.73 gears - I'm baffled why it' such a slug out of the hole.

Next up for mods: right rear air bag, possibly the alum. DS from my LS1 car, and a short belt to bypass the PS pump. I definately need to adjust the TV cable so it shifts lower too.

The motor still has an untouched TPI, valve covers have never been off, and the transmission has no mods as well.

 

I've been 13.0XX @ 106.XX. Street tires (BFG radial T/A's) and no nitrous. I'm hoping to break into the 11's with drag radials and my 100 shot.

 

tire height really shouldnt effect the trans shifting. thats only for electronic trans where they need to know the gears and tire height.

that shifting is really killing your times. you want to be around 5 grand at the max. get your trans checked out and make sure your TV cable is adjusted right. you have 2-3 tenths easily with just changing the shift points

as far as 60 foots, i'm not sure why your still somewhat slow. do you have any converter at all? how are u launching the car?

 

Concerning tire height, my shift points raise the instant I swap to the BFG's vs. my normal 245/50-16's on my ROH wheels. I went from a 245/50-16 to a 255/60-15 on my old 86' and it screwed the shift points up as well.

The car has a completely stock transmission including the converter. I launch the car by either flashing the converter off idle, of barely comming against the brakes to take a little slack out of the driveline. It's 60 fts within .02 - .03 regardless of the technique.

I know the speedometer is a hair off with the 3.73's, and there isn't a proper set of speedometer gears to get it dead accurate. I feel that plays a major role in my shifting woes.

 

I really couldn’t agree with you more.

I could see it if the cars were saddled with 2.73/2.77 gears like some of the 305/5 speed cars, but with 327’s, the auto tranny setup the way it was and the power band the way it is on the 350 TPI cars, you really have a fairly decent factory combination.

The Pontiacs got shitty intakes from thefactory, but that wasn’t hard to fix, and _really_ the exhaust wasn’t that bad.

After a couple of test and tunes worth of tweaking, my formula 350 managed to knock down a 13.59@100mph on a nice, cool fall night with the only aftermarket parts being an SLP cold air intake and cat back. Well, I did install a trans go shift kit, but that is because I bought the car with barely a second gear in it (it slipped badly), had the transgo sitting around (figured that it would already be installed if I ended up having to rebuild the tranny), and it at least got the car somewhat shifting (though the 1-2 shift took way longer than it should have). In other words, a properly working transmission would have been faster than my cobbled POS and the transgo.

My new project is an ’87 305/5 speed car with 2.73’s which is running a little funny that as far as I can tell is _dead stock_. It even has the stock cat back on it (the stock muffler has a small hole in it but not enough to hear yet) and it grinds a little on the 1-2 shift. I’m really hoping to see something in the mid/high 14’s out of the car as a baseline. If I don’t see under a 15 I’ll probably skip some of the mods that I have planned before the season is out and spend some time figuring out what is wrong with the car (id doesn’t help that I have a 3.50 geared 9” for it and the current well undergeared 10 bolt has a pretty bad pinion leak)

 

 

too much weight and not enough hp to be running in the 13s being stock
jasper 350 no upgrades internally, hooker headers, 3.73 posi, shift kit, real hard tires and cool conditions best it ever hooked.
1.9 60', can only leave at somewhere around 1500 to 1700, wont hold anymore, g rigged my e brake to help me stall better. ran 14.5 at 93 mph

 

1992 350 tpi l98 g92 with the only mods kn air filter,tpis airfoil,accel supercoil, underdrive pulley.
1.90's 60' time
13.76 e.t. 100.55 MPH
Less than $200 back then.

NO MODS
14.15 E.T.
97.5 MPH
Off the showroom floor.

 

New best a few weeks ago. Here's a cut n' paste from my original thread on the vette forum:

Jonecap and I headed out to the dragstrip today. I had a great day with some new bests all around:

On mota'-

1.807
8.251 @ 86.54
12.894 @ 103.33

Mota' + 100 shot-

1.747
7.696 @ 93.60
11.992 @ 112.42

The car is a 91 ZF6 with:

1.6 roller rockers
longtubes
Fearless Performance dyno tune
Centerforce clutch
4.10's
ET streets
Fearless performance dyno tune

http://forums.corvetteforum.com/show....php?t=1930826

 

In the sig.

Stock Manifolds and ypipe, stock TPI other then ported plenum

14.43 @ 97.7 MPH, spinning through 1st gear.

 

Did you run the car on the Corvette wheels/tires? If so, try putting the stock 16's back on, your 60's should improve.

I never updated mine either from last year....

https://www.thirdgen.org/forums/orga...t=#post3541948

 

12.82@104.3mph
355, AFR 180cc, Comp Cams XR-276 HR12, SLP runners, ported plenum/base, MAC shorties, Mufflex 4" exhaust, shakedown tune

 

I just went 8.416 at 80mph on the motor. My timing box took a dump so I couldn't run more than a 125 shot of spray but the car went 8.000 at 88mph on that shot with 36 degrees of timing. This was on the ET Street's with Weld Draglite skinnies up front and the new K member and pinto rack installed.

 

13.5 @ 98 mph!

BONE STOCK 350 TPI, with a 2800 converter, longtubes and a stock 3.27 gear. The BFG Drag Radials didnt hurt either.

Kevin

 

14.0@98 MPH. 2.07 60ft.

L98, full exhaust, AFPR, timing at 8 degrees, gutted airbox with K&n's. 2.77 9 bolt, street tires.

 

305tpi 5 speed cars never came with 2.73s or 2.77s, non G92 cars had 3.08s, G92 cars had 3.42 10b or 3.45 9b depending on the year

 

never did update mine. 12.95 at 103.8 on a 1.71 60 foot. full bolt on L98. Stealth ram on top instead of TPI

 

(I'm working on making a legible sig...)
Still a TPI, N/A all CA smog legal parts.
Previous best 1/4 13.35@101; 285h/320tq (zz9 cam, may '08.)

Since my last post it now has a Lt4 hot cam and fixed bad piston.

Current: dynoed 322hp & 378tq (January), plan to race again in may.

edit: Oh, posted a graph and numbers. #85 and 86. (Just to scare those poor BBK people, I guess?)
https://www.thirdgen.org/forums/alte...ke-sale-2.html

(just changed ANCIENT fuel filter, hope to pick up more hp!)

 

Boy this is an oldie goldie!! IMO, I'd like to think TPI refers to an intake that uses a tuned set of runners. The long tube runner system, Accel SuperRam and the SLP T-RAM all have tuned length runners and a common plenum. All have these intakes give the similar effects to the air intake charge. Just me opinion.

 

I will fill you all in when my little vortec TPI is done, its should be up there for an all motor stock bottom end TPI.

Kevin

 

Well, then I can show you at least one '87 TA and one '87 IROC that didn't come the way they came, even though their RPO codes say they did.

 

So your saying you know of two 87 305 5spd cars that have 2.73 gears but have the GU4 code to say otherwise? That's kind of odd don't you think? There are some fluke cars out there, but do you think it's possible someone swapped in 2.73 rears? Have you counted the teeth on the ring and pinion to determine it's a 2.7x ratio?

 

That was a confusing response, huh?

I meant that they have 2.73's and they have sticker with an RPO code that says that's what they have.

 

No 1/4 mile tracks around here , so this is 660ft, and the first time ever driving. This is not my BEST, but most consistent.

rt .853
60ft 2.294
660ft 9.011@74.13mph

appears to calculate out to high 13sec.

3504blt, swirl port heads, tpi intake, slp runners, stock TB, stock intake, headers, t5, 3.23 gears, OBD2 custom tune.

 

What does a stock LS motor run?

 

87-93 octane... lol

 

14.8 bone stock with the floor mats and the luggage cover.
Cat-less SLP headers, K&N filter, AC and smog delete, flowmaster and metco poly LCA's pulled a 13.9 with 1.9.