Hey guys, I took my nearly stock 89 Formula (mods in sig) to the track today. It was about 65 degrees and just a little humid. This is my second time drag racing, but the 1st with my L98 car. The compulink autostart was off so I believe reaction time was a huge factor. I used stock bald tires with barely any treads left too.My best 3 runs are below.....

R/T- .758
60' - 2.316
1/8- 9.928- 71.15 MPH
1/4- 15.41- 89.81 MPH 45 PSI front tires, 38 PSI rears, coolant temp at 195


R/T- .567
60' -2.377
1/8- 9.991- 71.08 MPH
1/4- 15.48- 89.59 MPH 45 PSI front tires, 30 PSI rears, coolant temp 185

R/T- .475
60' - 2.330
1/8- 9.990- 70.68 MPH
1/4- 15.52- 89.14 MPH 45 PSI fronts, 24 PSI rears, coolant temp near 205
(raced an 02 Mustang GT this round which was auto and had exhaust mods. He ran a 14.46 at 98.74 with a RT of .144 and a 60 ft of 2.31)


I know my 6o foots were crappy but it didnt seem like I was spinning that bad but it was hard for me to tell. My car has 116,000 miles and it runs pretty strong too. I just recently added a stock fuel pump, a CAI, Mobil 1 synthetic oil, Royal Purple gear oil, fresh cap and rotor, coil, new rear shocks, and I also removed the spare tire and jack, and the cargo cover. Why does my car run such crappy times???? This is aggravating!!!

 

My wife's car is almost exactly like yours. Same year, motor, gears, and close to the same mods. I rebuilt the motor 18k ago. Last time it went to the track on stock suspension it went 9.2 on the motor. So mabye the 116k its not as strong as you think. Do a compression test to see your cylender numbers.

 

You should be running nearly a full second faster then the times you ran. Something isn't right. Pull your codes, check your timing, fix your dead cylinder... Seriously.

You need to get your temps down, rig a manual fan switch and turn the engine off while you're in the staging lanes but leave the fan running to cool the radiator.

 

I dont have any dead cylinders, my engine is running strong on all 8. Plus my idle is very steady. I haven't had a check engine light since I've owned this car. But I do need to check the timing and the fan switch sounds like an awesome idea. Something else has got to be wrong. But Im really not sure where to start looking.

 

This might be a stupid question but are you sure it's a 350? My 305 runs a 15.4 @ 89 mph.

 

Yes its a 350, and yes that's a stupid question...

 

No it's not, your "350" runs like a 305. They look exactly the same and many people buy 350's when they're really 305's. I've known people who blow up their L98's, and just get a LB9 from the junkyard and sell it as a 350.


Start with small stuff like timing. It would be great if you could hook up your car to a laptop.

 

I wouldnt say its running ok. My stock 89 GTA vert ran 14.9's @ 93, no mods whatsoever and it was in need of a tune up.

 

And here's a story from the other side of the fence. My buddy's bone stock 87 305 TPI GTA couldn't even break into the 15s (16.03 was his best run) this past fall, and he had better 60fts than you 50k mile car in perfect running condition. Your 60ft is killing you, for sure, but in my experience you're not too far off the mark. I had an 89 GTA 350 that I ran in various stages of modification, stock was low 15s, with a cam, headers, exhaust, cold air, I got it down to 14.2 or somesuch.

These cars are known for having wildly different performance potential out of the box; some were crazy fast ( saw a guy with a bone stock 88 305 TPI run low 14s one year) and some are dog slow (my buddy's GTA). Get some decent tires, do some suspension mods, and see what you get then.

 

Yeah I hear You about the wide range of potential on these cars Gunner. But it really seems like something is wrong. A lightweight, slightly modded L98 car should trap at least 92 or 93 mph in the quarter. But my 60 foots were horrible!!! Shouldn't an L98 knock down somewhere between 2.00 and 2.10?

 

Don't look too much at your RT, or 60' times, they don't have anything to do w/ the power output of your car. Your MPH is the indicator of the amount of hp your putting out. No matter what your 60' times (1.6 or 2.4) the MPH should stay about the same.

One thing that helped my 60' was to just to let off the brake w/ your right foot then smash the gas, don't try to load up the car by holding your left foot on the brake and bringing it to 2k rpm or anything, this made my car spin all through 1st and 2nd. Just launch off idle.

Good luck

 

Your 60ft will affect your ET and MPH. When I ran this past summer first on street tires, I posted a best of 13.2@108mph with a 2.3 60ft. Switched to worn out drag radials, dropped the 60ft to 1.9 and ran 12.5@111.1mph. The faster you get going off the line the faster you'll be going at the end of the track. His mph is low, but his 60ft times are awful. I'd like to see what he'd run with a sub-2 second 60ft.

 

sorry but .3 of a 60' will not give him a full second in the 1/4 mile...something is definently wrong with his car.

Are you manually shifting it? If so stick it and D and let it do the work itself.

That car should be running at the very LEAST a 14.2-14.3 with a decent 60'

I ran 14.0 almost bone stock...1.9' 60 ft.

Id like to know the 8th digit in your VIN.

 

The bald tires are probably causing you huge problems. A quality name brand performance tire with decent tread would probably net you better results. Drag radials or straight slicks might not be a bad idea if you want the best possible times. Another thing to check would be the rear differential, when my times dropped from low 14's to mid 15's it was a direct result of the posi going out. It's hard to hook up with one tire, spinning 3/4 of the way down the track.

Something is definitely wrong, it's either way out of tune or something is broken. Bone stock that car should run at worst a 14.7.

There's some VERY good advice in this thread. I love the 305 question. I'd be pulling the valve covers on both heads to check the castings, check the casting numbers on the block, and the VIN stamp on the passengers front of the block. You could have one low output 305 head, or any number of mismatch issues. The history of a car is never a definite unless you verify for yourself.

The suggestion to leave the trans in D, not OD, and not manually shifting, is a good one too.

It's not something small, but it may take some digging to find the problem. Find someone in your area that knows thirdgens and TPI and have them drive your car once. Something this big should be fairly obvious.

 

my bonestock 86 lb9 went 15.86 at 85mph with a 2.1 60' then with a flowmaster cat-back and holley afpr set at 45 it went 15.400 at 86mph with a 2.009 60'. with over 100k on the odo i think she did pretty good. an l98 car should be in the 14's, but your 60' is killin you and your trap speeds are low for a 350. give that baby a tune up and compression test and set that timing at 6degrees btdc(that is the stock setting on my car for 87 octane and it runs great.,)

 

i live in tulsa.... i'm trapping 90 mph in the 1/4

 

I recently an a 14.0 on street tires with nearly identical 60 foot times on a stock ANTIQUE 350 TPI after long tubes, duals, and a tune up. I'de say the problem is you need mods, free mods even. My car ran a 14.7 when the motor was first installed that was BONE stock with short tubes and a complete crap exhaust, we're talking paper filters stock here. After some porting to the lower, porting to the plenum, working over the runners a bit, resetting the timing, new plugs wires etc. the car did a 13.5 on ET Streets at 100. These cars respond amazingly well to mods so don't be down hearted about your times, just get to sorting the car out and modding it.

 

I'm pretty certain the car has the stock L98. All my codes have an 8 in the last letter of the vin and there is no evidence of any motor swap mischief. When I ran the car, I left it in direct drive, not overdrive. I have owned an 89 GTA with a bone stock L98 and an 87 TA with a bone stock 305 TPI, and this car seems quicker than both. I know that I really need some new tires so I'm gonna get a set of BF Goodrich 255's for the rear. I think that if I can get my 60 foots down I'll break into the high 14's with some cooler weather. I am gonna install some new valve covers soon and I'll let You guys know what the head castings are. And I'm also gonna reset the timing and check my fuel pressure before I go to the track next.

 

[QUOTE=rik89gta;3139368]I'm pretty certain the car has the stock L98. All my codes have an 8 in the last letter of the vin and there is no evidence of any motor swap mischief. QUOTE]

the 8th digit of the VIN should be an 8 if you have a 350. F if you have an LB9. The last digit of the VIN has nothing to do with option codes.

 

Also, radials don't respond the same way as slicks with tire pressure changes. You're ETs and MPH show it.

Timing light would be the first thing on my Christmas list if I were you. Then, a wideband like Innovate's LM1.

 

I almost forgot to mention, a friends 89 Formula 350 with long tubes, duals, and a CAI went 14.7 with awful 60 foot times as well. I can't remember exactly how bad they were but they were pretty bad. We couldn't get his car below 200 degrees at the track so I'm sure that was part of it. His mph was anywhere from 95 to 97.

 

I would agree that is pretty strange. My high mileage (Bone STOCK) 350 TPI AUTO With 2.73 GEARS IROC-Z runs consistent 14.2 at 94-95 MPH with a 1.8 60 ft.

The major mods that I have (which really help that decent 60 ft time) are a 2800 converter and a set of 26" BFG drag radials.

Kevin

 

60ft times or for that matter ET have NOTHING to do with your mph.

You're down on HP. Simple as that.

 

Your mph is only 70 MPH something is definantly up with your car. My best time so for with my 350 TPI is a 15.1 at 93 MPH on bad tires and thats with a busted transmission mount and the SES light coming on 3/4 of the way down the track. I would make sure your timing is set correctly, change the cap and rotor, new plugs and wires and give it a good sea foam treatment. Also test your injectors to make sure all of them are working correctly. If you dont notice a difference after that then get a compression test.

 

yeah my completly stock 88 iroc with 100k runs 9.6 @ 74mph in the 1/8 ur car cannot be a 350 lol. or if it is its dieing. And why is ur car running that hot when its 60degrees outside, my car barley gets over 150 in the 80degree summer weather.

 

Well guys, I'm on the right path to better et's. I replaced the spark plugs today and the plugs that were in there were very worn. I used stock Delco's gapped to about .37 The car runs smoother and has more throttle response now. I also got a rear set of Riken Raptor performance tires. They are supremely better than my old, cheap, bald tires. I am gonna look at timing and fuel pressure next weekend. I will keep You guys posted on my drag times. I should be going to the track in 2 weeks. Rik

 

R/T:.-.427
1/8- 9.65 @ 82mph
1/4- 15.22 @ 91mph

All on stock 1991 Formula 305 Tpi 5-speed
3.42 rear end Launching at 3700rpm on street tires with 22psi

 

If you want to really improve those times pull the entire TPI setup off buy some carbide cutter bits and port the base, siamese the plenum, knock out the EGR walls, and radius the runner entries to match the siamesing. This will make a very noticeable difference in your car.

 

Well all that seems like a good idea, but I dont have the time to take my intake manifold off and port everything. If anything, I would at least pull off the plenum and work with that.

 

dont mess with porting yet. the car isnt running right as it is, so work to get it running where it should be first.

that car with those mods on stock converter should be capable of 2.0-2.1 60 foots. should run near 74-75mph in the 1/8 and 94-96 in the 1/4.

my 150K mile motor had headers and flowmaster catback with 2800 stall and stock 2.77 gears on street tires and went 1.88 60 foot, 13.89 at 97mph, and my motor was runnin hot. now with gears and slicks, it goes 13.63 on a 1.75 60' spinning just a tad bid.

I noticed you have ebay cold air intake. hows that working with the mass airflow sensor?

i'd look into those plugs like you did, maybe change the cap and rotor on the distributor..

then check the timing and fuel pressure. i'd keep fuel pressure near stock at 43psi or so. timing should be anywhere in the 6-10 degrees range base timing after disconnecting the est wire.

look over all your sensors and stuff too. make sure they are all in good condition. they usually would throw a code tho if not.

make sure your car isnt shifting over 5 grand either. 4600 seems about right for a L98. my trans tho shifts at 5K. higher than i'd like.

if none of that proves any effect, look into gettin new valve springs. perhaps they are worn out? see if that improves it at all.

make sure you dont have any vaccum leaks either. thats another thing that you'd have to be sure of to get all the performance out of it

the weather/altitude didnt effect your times too much since that mustang trapped 98 right were i would expect one to be. you should be near 94-95 easy.

 

I just did the plugs yesterday and the cap, rotor, coil before my track outing. My tranny shifts at exactly 5,000 on every shift, and it shifts nice and firm. My cai seems to be working just fine. It seemed to give the engine a tad more power. My maf has only the back screen removed on the side closest to the throttle body for now. I have only had one ses light set off, and it was for egr. And it only came on once on a long freeway drive after I bought the car a while back. I cleared the codes and it has never come back. But.... I do have a few vaccum leaks. The air pump is still on the belt drive and the diverter box has been yanked. One of the hoses going to the air pipes on the pass side manifold is unplugged, but I wouldn't think that that would make a difference. I also just got a rear set of Riken Raptor tires. They seem like theyd be much better than my old bald tires. Im hoipefully gonna be able to look at my fuel pressure and timing next weekend and see what I'm at. But overall the car seems fast. The car fires right up, hardly burns any oil, and idles real smooth and revs decently quick. the torque is awesome!! It seems to peak higher and push me back in the seat (from 2,800-4,000) a little better than my old LS1 car that had bolt ons and 3.73's. Although the LS1 had a steadier curve and reved strong to 6k.... This car naturally falls on its face after 4,500 rpms. It just doesnt seem like these track times are doing my car any justice. Anyways, I am gonna order a few small bolt on's like an air foil and an Accel ignition module. Desreen the rest of the maf, clean the throttle body out, and do the throttle body coolant bypass. I doubt they'll make a huge difference. But they surely couldn't hurt my et.

 

idk man, i'd look into gettin rid of the air pump and cloggin the header AIR passages.

i'm more concerned about vaccum/air leaks in the TPI manifold/runners/plenum and the connections goin to those parts.



the ONLY other thing i could think of why ur mph is so low is your air dam could be to low and tripping the first beam early. BUT doubtful as your car looks to be sittin fairly tall. and your 1/8 mile mph is low as well

my car is lowered on eibach prokit springs. the front end is slammed and at my track, in the right lane, i trap 92-93 max. left lane i'm 96-99 dependin on weather. the right lane beams are posistioned funny so that my air dam is hittin the beam first before the tires and making it seem like its traveling longer distance, thus making my trap speed slower. other stock ride height cars dont seem to be having this problem, but other lowered cars do seem to have this problem

 

Wow, there are some fast L98s out there. Best i got outa my '91 GTA was a 14.8 @ 95 MPH with a 2.4 60ft. I kept driving through the water box. DUH! . Without doing that i'm thinking i would have hit mid-low 14's .no mods except i ran w/o a airfilter.

 

How many miles are on your L98 though? just that could make a difference in your times, as high miles=worn engine unless replaced or rebuilt. But yeah try going down the track w/o going through the water box, I think that would make a pretty good difference.

 

That is pretty slow for an L98. My 1997 3.8 Buick LeSabre was only a few tenths slower than that.

 

She's kicking at about 72k miles now. Im thinking im doing ok powerwise with a 95MPH trap. And even friendly races with some other known racers in my area that have high 13 quaters and 97-98MPH traps, my GTA sticks close to the rear bumper pretty consistenly. And i don't think ive ever lost to a race to a stock auto LT1 Pre- OBDII ones anyways.

327_TPI_77_Maro... Were you refering to me. I'd be amazed to see a tank of a Buick go that quick. A Regal GS are low 15sec cars stock.

 

no i think he ment the original posters times

 

I had an Intense Racing custom PCM flash in my 1997 LeSabre, 3800 series II, 205 hp. The PCM moved the shift points up to 6000 rpms and added 3-4 deg more timing in certain areas of the map, requiring 93 octane. It did run high 15s, we ran it at Cecil County dragway in MD before I sold the car. The LeSabre, although large, was actually a pretty light car. Very thin sheet metal, lots o' plastic. So 15s is definitely 4 door territory.

 

I dont completely agree with that. As long as its a fresh tune up and the compression is up in all cylinders itll run like almost new. My car has over 130k now and runs like a champ...all the time. If you keep up on preventive maintenance to these car they will run good...

 

Yes I also agree with that. Rugular tuneups and good compression will leave car running great. But sometimes it doesnt matter what you do, the engine is worn and needs rebuilt. I meant outgageously high miles.

 

im not going to read the tons of posts above, but one thing i did notice on the posts i read, is that no one mentioned density altitude or even altitude. I live in amarillo tx, im guessing OKC isnt too far off from our terrible air. ive NEVER raced on a day where DA was lower than 4500ft!!!!!!!!!! my best run in a car almost exactly the same (except mine was a 355) was 14.88 @ about 92.5 with a 2.14 60' corrected for altitude it comes out to about a 14.3 at something like 96....

 

true...but the mustang he raced went 98mph....which is perfect for a 99-04 GT with exhaust mods. thats what mustangs do at my track and my L98 went 13.89 at 97mph on street tires with 2.77's

 

I'm surprised that you would even take it to the track without a FULL tune up first. Why didn't you change the plugs before? And have you done the plug wires yet (and I mean use good low resistance wires...not stock GM wires). Also, ALL filters; verify the timing.

BTW, you never did mention if you shifted manually, and at what rpm your tranny is shifting (even when in D)? If you get a scan tool, one of the "internal problems" that seems to make one car faster than another is Knock Retard.

Often, one and the biggest causes for knock retard is TOO MUCH TIMING (and grade of gasoline)! Advancing the timing on a bone stock car can often have adverse affects on your performance ... contrary to most people's believes.

When I've hooked up a scan tool and started to monitor their engine, I would find that while the ECM is programmed to give just over 30* of total timing (depends on your model year), usually the knock sensor is picking up inaudible knock and pulling out a ton of timing. I've seen it where they are not even getting 20* of timing in WOT. (And that is the primary reason their car was pig slow).

For an experiment, I would limit the amount of timing the ECM could pull out to just 1* and they generally would have AUDIBLE knock occur around 25*. I would set the spark advance to just under 25* and LOW AND BEHOLD, there car ran noticeably faster.

Morale of the story, find someone with a scan tool and do some WOT runs to find out how much retard the ECM is pulling out when the knock sensor kicks in.

Also, make sure you put in the highest grade of gasoline you can buy at the pump.

 

Well guys, I went to the track again yesterday and I am very impressed with my car! The temp was 42 degrees with humidity near 65%

Here are my best few runs....

Run 1
60 ft- 2.113
1/8th-9.060 at 77.11 mph
1/4- 14.101 at 98.30 mph

Run 2
60 ft- 2.119
1/8th-9.066 at 77.12 mph
1/4- 14.110 at 98.26 mph

Run 3
60 ft- 2.191
1/8th-9.098 at 77.57 mph
1/4- 14.115 at 98.63 mph

Most of my times were in the 14.10- 14.2 range. My Formy was running rather consistent. However I did run a 14.5, but I tried manually shifting and it obviously didn't work.

The huge improvement in et came from a number of things....
Such as the new Riken Raptor tires (before I was using crappy, bald, dry rotted stock tires.

The new Accel ignition module (the stock GM one was running weak)
I adjusted my timing to 8 deg btdc (before it was at 2 deg atdc)
Adjusted the tps to .54 volts (it was at .38 before I adjusted it)
Changed all the spark plugs, wires, o2 sensor, removed the smog pump and all smog equipment, descreened the maf, installed an SLP air foil, did the throttle body coolant bypass, changed the tranny fluid (it shifts much firmer now) I rigged up a manual fan switch to use in the pits, removed the cowl cover on the Formula hood, and I fixed a few vacuum hoses. Oh yeah, the weather was also much cooler this time out.

So all in all, I am very impressed and suprised with how well my car performed!
Heck, I was hanging with my buddies $21,000 04 GTO halfway down the track! But after the 1/8th he would pull 4 or 5 car lengths on me en route to his 13.5's. But hey it's a 6 speed LS1. It makes much more power.
But I wanna give a big....... to all those who gave me advice and clues on what to check and fix up for my next track outing. Later

 

I just found this thread and i must say that you made good progress but i do fault you for going anywhere near a track with bald tires and in need of a tune-up never do that again!!!!!!!!Now find some time and port the crap out of your tpi and get some long tube headers and dr's.If you want to really want to get every tenth try removing the front sway bar and wonder bar when you go to the track then brag about running side by side with your buddies GTO he will hate you for it

 

I have a set of Vortec heads that are gonna be bolted to a forged 383 with HSR, 1 3/4 headers, and a healthy cam with a 2,800 stall. My buddy is gonna help me install it all. He gets to keep the old longblock when it's all said and done. His LO3 powered RS could definitely use it. I don't think his GTO will even stand a chance!

 

hey thanks for the update sounds like your car is up and running good.

i ran low low 14.0-14.1's all day long with a 60 foot near 2.0. but was consistent 13.9's and some 13.8's when i had lower 1.9x 60's and a few 1.88-1.89 60 foots

 

This thread has helped me out a great deal. When I went to the track in my L98 it was like 80* out and I ran a 15.15 in the 1/4. Next time I go, I hope I run in the low 14s.. Thanks Abunch!!!

 

I had a rather unique problem with my Firebird a few years ago. The car was running fine, no check engine light. One day I went out and the car would not start at all. It would crank, but there was no fual, ignitions etc. It turn out to be the computer, ECM. After replacing the ECM, the new ECM triggered o2 sensor code. It turned out that the ground to the O2 sensor was broken in the harness.

Anyway the moral of the story is, you need to connect it to an computer and check the full operaiton of your ECM.

 

If i were you i would move up to a set of 3.73 gears once you get the new setup to really use the upper rpm power you will have.If you car isnt a daily driver then i would go 3000-3200 stall