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Ok this been bothering me L98 Help Please!


Gone but not forgotten
Feb 12, 2002
Annapolis Maryland
1987 Redskin Red Coupe
as you all know i tracked the car 3 weeks ago and only went:

car was nice and cool. in the 130 water temp range. this should of been the run :(
Temp: 53
R/T: .461
60' 1.826 <----- Best 60' on Goodyear F1's was 1.815 now on BFG DR's
330 5.427
1/8 8.423 <----- Best 1/8 mile time ever
MPH 81.11
1000 10.997 <---- Best 1000' time ever.
1/4 13.191
MPH 103.34

this run water temps was creeping up on me and was over 160 probably in the 190 range. this is why the car ran .2 off always does :(
Temp: 53
R/T: .455
60' 1.894
330 5.542
1/8 8.560
MPH 80.68
1000 11.149
1/4 13.358
MPH 102.70

car was nice and cool and thought this one could be the one also :(
Temp: 51
R/T: .691
60' 1.851
330 5.454
1/8 8.452
MPH 82.64
1000 11.030
1/4 13.227
MPH 105.04 <------ only run to hit 105 mph and was a weak 105 mph also

got hot lapped and of course the car ran exactly .2 off like it always does :(
Temp: 50
R/T: .554 <----- did start finding the bulb though :D
60' 1.901
330 5.569
1/8 8.616
MPH 79.80
1000 11.232
1/4 13.461
MPH 101.79

car is an 87 coupe, A4, stock 1600 stall, 2.59 rear gears, with 70,000 miles

Mods that day were as Follows:
K&N open air box, MAF descreened, TB Bypassed, 160* T-Stat, Accel Super Coil, 12* degree advance timing, Cut Back AC Delco plugs gapped at .040 Indexed, TPiS Long Tube Headers, !Air, Air Elim Pulley, !EGR, Crank Pulley, and KBD Targa 3" Mufflers. Hayden Tranny cooler. Stock 1600 rpm stall, 2.59 rear gear on 275/40/17" BF Goodrich Drag Radials.

Only mods different from these runs

was KBD mufflers which more less are straight pipes with resonators like glass packs, Air Elim pulley, Crank Pulley, DR's and the Air Mod...lol back in March when i was running upper end of 105 mph the air was +700 DA at 65+ degrees and this night started about -300. i'm guessing my best 2 runs came around -500 as end of the night was in the -700 to -800 DA. humidity was rather high around 70-80% if memory serves me right.

i thought maybe the DR's caused the 3 MPH drop off, which BTW still could be the issue, or the Mufflers capping up a few ponies. car is running strong so i thought and actually is so i think. new Accel Cap, Rotor, wires, and cut back plugs gapped at .040. car ran the same on .035 gap. car runs strong thru all the gears with no hesitation.

The Problem:
a few weeks before the track i noticed the car would be hard to start when cold. i start the car and it just turns over for a few seconds then starts but idles at 300-400 rpm and staggers for a few second then clears up and idle goes to 1000 rpm until car warms up after about 10-15 seconds then idles down which is normal besides the staggering upon start up and idle at 300-400 rpm. now it's to the point i help it by cracking the butterflies open a hair.

i *think* i've narrowed it down 1 of 6 things but would like some input. 1 i can check off which i will explain later.

1. bent pushrod or 2. the car has never seen more than 6000 rpms for a split second so this baffles me but would be the reason if a valve is hanging slightly open. no unusual noises coming from engine bay though so this baffles me and i am leaning towards another problem

2. injectors are leaking causing fouling of the plugs. this would explain hard starts. maybe the cold injector is hanging open? thoughts? i would think under WOT the car would lean out though? on the dyno it back in late febuary after the header install the car ran a 12.9:1 A/F ratio. this could explain why the car is running super rich. i failed the emmisions test with 530 hydro carbons compared to state maximum of 220. this means the car is running real rich. i have tuned and know others that have tuned and gotton cars with no air, egr, and gutted or no cats thru this test as i'm not worried. worst case scenario i through a cat on it.

3. dirty intake and TB. not sure if this could lose 3+ mph though but could be cleaned. it is starting to get dark in there after shining a flash light in thru the butterflies. butterflies are not gummy or greasy when i run my finger on the back of the plate.

4. the DR's with stock 1600 stall and 2.59 gear is grabbing too well. i'm not sure i can not justify this due to the fact i still pulled a better 60' time on Goodyear F1's but could be the reason why it dropped MPH.

5. the KBD 3" tipped Mufflers could be pulling a few ponies but the arguement here is 3+ mph?


6. Car is pulling timing somereason. this could be the reason but i haven't touched the distributor at all and the same tune is on the car when i went the 13.18 back in march. am i missing something here? maybe something to check? i know i would have to have a scanner of some sort like a snap on 3000 or something to measure knock and or timing advance. i'm leaning towards this but would like some input. this doesn't, atleast to me, explain the hard starts.

Well saturday night i pulled the mufflers and sold them to a friend and went back to dumps on the rear Y pipe. talked to another friend and he suggested to put a bottle of injection cleaner in it so i did. took the car out both friday and saturday night and drove it hard. didn't make it to the track friday night to test due to the air being bad and told a friend i'd stop over and help him move. only drove the car maybe 40 miles total friday night with the injection cleaner in it with no noticable change. saturday night after pulling the mufflers i took it out and ran it pretty hard and the car came to life! the air wasn't that good this night at 65 degrees but i could turn the drag radials over at will upto 20 mph. used to do this with the F1's easily. the car from a dig would light them up thru 1st and into 2nd. i was real happy and thought the combination of the injection cleaner and the dumps back on the car finally was showing it's potential.

well sunday it went back downhill to back to hard starts and only spinning 10 or 15' from a dig and get nothing from a roll but the car, to me, still pulls hard.

i am pretty stumped and would like some input or idea's to check before i have to pull the intake for a good clean and maybe 24 lbs injectors anyway getting it ready for the build.

i'm very tempted to just throw the LT1 intake on, ZZ409 cam, and a set of D 113 heads i'm getting. i'm gonna send the heads out for some porting, valve resizing, and new hardware with 1.6 rr's and a nice size shot. this would be the wintertime project and do the 396 short block build in spring time while i'm running the car. the problem here is i'm having fun seeing where i can take the stock stuff! i want to hit 12's on stock stuff with mild bolt on's. my goal on the stock stuff was 300 rwhp and 400 rwtq. i wouldn't mind porting and siamesing the TPI though and this was my plans before fall racing season but been too busy to find the time to pull it and port it so i might stay on stock stuff since i'm so close to my goals but on the other hand it's very tempting to throw the H/C/I on and run low low 12's or even mid to high 11's and juice it. very tempting so you guys see my dilema here.

thanks for your input!
Firstly, I think you have too much info cruising about between yer ears!...LOL. I reply despite your political banner, BTW.

You could well be at that point in your mods where the ECM cannot lean the car to the point needed; hence the running rich, as you have seen from ample evidence. I submit that your hard run 'blew the carbon out' as I used to enjoy in my Mom's Poncho, but after more 'normal' driving, it began to load up again.

Putting a CAT on a rich-running car will clog it, in time. Been there.

If your season is ending, maybe it is time to do the other mods you have in mind, then have a custom chip done to make all that stuff deliver its promise.

Man, I had those rear pipes and found them loud AND restrictive. Good thing I got them free (gave them away, too.)
As I look through your post there is one variable that I can't account for, fuel. Did what ever was in the fuel injector cleaner provide a mix the engine liked better? Did you switch gas or was it switched on you? I know they change additive mixes by the season.

What about a clog in the fuel return line? Pressure goes up, mixture gets richer. Cleaner relieved the clog, but as it's potency goes down the clog returns and pressure goes back up.

Good Luck.................
thanks fella's for your responses!

fuel pressure on stock FPR is at 45 psi. only thing in the fuel system that was changed was the filter about a month or so ago. DR's been on since end of september and it never spun them over like it did last saturday night. felt like i had street tires on the car.

i'm waiting for Rich to finish up his project so we can start data logging the information so Jeff can burn our chips. (Rich has all the stuff needed to get us started on the chip for data logging, just waiting on him)


i still love ya man even if you did vote for SKerry Kerry :D i didnt think 12's would be this hard since i came close on the 13.18 at 105.84 mph pass back in march...lol just let me hit a goshdarn 12 second slip then i'll put the other mods on and say Fragoogle it! :L

BTW tracks close mid December so i still have a few more weeks to achieve my goals ;)

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