Detroitmuscle

iTrader: (16)

Here is an update to my previous thread.
https://ls1tech.com/forums/drag-racing-results/562394-whats-wrong-here.html

Went to the track this past weekend with a new fuel pump and set of M/T DRs hoping to at least hit low 12s. This was my best time, off my memory, don't have the timeslip with me currently but will update with full slip tonite. My runs were all pretty consistant within a tenth or two.


60' 1.79
1/4 ET 12.59
1/4 mph 111

I hit a lot of 108mph runs as well. Any ideas? I'm thinking my injectors may be maxed out.

n2o

iTrader: (1)

The injectors are not maxed out or at least that is not what is slowing you down. Have you been to the dyno after the re tune? Without any more info here I have to be thinking converter. I don't see anything else that would hinder your car? Or not with 380 plus hp to the tires. I ran 7.40s with 1.7 60's and dynoed 370 tuned on a Mustang dyno. Unless your weight is like 4400lb. My car probaly weighs 3550-3600 with me in it.

Detroitmuscle

iTrader: (16)

My car put down 362 on a mustang dyno after the tune, but that was with a bad fuel pump. My buddy has a similar setup and his injectors are maxed out. The car only drops just below 5K on shifts as well I'm just stumped here.

TeEnAgE pHeNoM

iTrader: (6)

How many rpm's do you spin the car to? With that setup your car should run easy 11's.

TeEnAgE pHeNoM

iTrader: (6)

Hmm seems like the pump didn't help any. Your 60' was way better from your previous times. What was your 1/8th mile time on that run?

Detroitmuscle

iTrader: (16)

It very well could still be the fuel pump. The car is spun to 6500 and the 1/8 ET was 8.21 at 93.96mph

Phil99vette

iTrader: (11)

Couple of questions....

1) What is your raceweight?
2) What is the altitude or DA if you have it?
- air temp
- baro pressure
- dew point
3) What did the car make on the dyno?

Detroitmuscle

iTrader: (16)

I'm unsure of the raceweight but its gotta be near stock, rear seats and all with it optioned out. DA I'm usure of. The car made 362 tuned on a Mustang dyno with the converter unlocked and at the time it had a dying fuel pump.

Phil99vette

iTrader: (11)

Your track altitude
Air temp
Barometric pressure
Dew point
www.weather.com and input zip to get close, track should have a web page that lists altitude

venom ws7

iTrader: (13)

i was running cam only and my injectors were maxed out throw a bigger one and fuel pump.

Rubadubdub

Said it before and I'll say it again, you need to change that converter for something with more stall. I suggest a Yank only cause a buddy of mine has cheaped out on at least 10 converters until he finally got a Yank. Well guess what, the Yank gave him his best ET and MPH ever. Your torque is really low, I had the same problem when I had a ProTorque 3500 stall in my old H/C (TEA 1.5s/TR 224/Pacesetters) 98 Z28. It still ran 11.8s at 115 w/a 1.64 60' at full weight on 245 Nitto DRs (stock 98 injectors, no tune, 15* of timing due to a bad knock sensor, bouncing off the rev limiter on 2-3 shift, 75-80* day). When I replaced the TR224 cam for an R1 (still no tuning) I dynoed the car and made 372/320 unlocked. Junk converter (but it did pull the left wheel off the ground lol). Never ran the car at the track with the R1.

Now, I don't necessarily think that's the only problem you have. Log some runs and see what the hell is going on. I doubt it's the injectors unless they're real dirty/clogged.

Who did the tuning on the car? Have you done a compression/leak down test on the car?

TeEnAgE pHeNoM

iTrader: (6)

Yea yanks are good stalls, but since his 1/8th time is good and the mph is strong, the converter could be slipping on the big end. Maybe your tranny is slipping?

Detroitmuscle

iTrader: (16)

I couldn't find the altitude on there website, which hasn't been updated in years, but if you wanna look up the location the zip is 48446. As for the converter, I know. I have a Yank SS4000E sitting in my garage but it has to be sent to yank to be looked over and this winter I was planning on swapping it in. The car is tuned by a local guy who tunes many cars and is highly recommended, he also tuned the car when it had my old LPE cam in it and that ran a faster 12.55 at 114 on Nittos. Right now everything and anything is possible, its just a matter of narrowing it all down. The trans doesn't feel like its slipping but I know it won't last forever and maybe it is on its way out.

Detroitmuscle

iTrader: (16)

Any other ideas or signs that my tranny or converter may be slipping?

n2o

iTrader: (1)

Yeah mph in the 1/4

86 IROC

iTrader: (14)

Agreed, you trap almost 94 in the 1/8, and only 111 in the 1/4. That means you only 17 MPH from the 1/8 to the 1/4. It's laying down big time. My bolt on set up, stock cam & heads, picked up 23.5 - 24 MPH from the 1/8 to the 1/4. I'd expect your car to at least do the same.

And 8.2 in the 1/8 is a horrible ET for almost 94 MPH of trap speed. My car did 7.81 @ 88.5 - 89 MPH. I would expect your car to be running mid 7's in the 1/8 no problem with that kind of MPH.

It sounds like you need to data log that thing on a 1/4 mile blast to see what's going on.

What gear are you running in it? With that sized cam, I'd think you would need a 3.73 - 4.10 to really make it work.

Just tossing in my $0.10 worth...

Detroitmuscle

iTrader: (16)

Well other than the very shitty trap speeds the trans seems to shift perfect but I would suspect the converter although it has never seemed to run oddly. I'm currently on the stock 3.23s since there is no use to swap until I get a 12 bolt, but I know that a higher stall will do wonders. Could a converter that is slipping cause most of the loss in mph here?

JNorris

iTrader: (4)

Assuming your passes were at 3pm on the 23rd the DA was 2390ft
Elevation at Zip code 48446 is 846ft
Temp was 72
Dew point was 63
Barometric pressure was 29.70
Corrected to sea level mph and ET 12.25 @ 114 1/8 = 7.99 @ 96.53
My head and cam car usually gains ~24mph from the 1/8 to the ¼ which based on your uncorrected 1/8 mph your ¼ mph should be ~ 118mph

John

Detroitmuscle

iTrader: (16)

The passes were indeed made aroiund 3pm. Is that DA or altitude bad? Those times still seem super weak for a car with my mods. The guy I bought my Yank off of ran 11.80s with ported stock heads and an FM13 on the same track.

Rubadubdub

Bro, you need to make some passes and scan it. This could shed some light on the situation.