LT1 Based Engine Tech 1993-1997 LT1/LT4 Engine Related

went to the track and not too happy---HELP

Old 09-23-2004, 10:01 AM
  #1  
Registered User
Thread Starter
 
"White Knight"'s Avatar
 
Join Date: Nov 2002
Location: Michigan
Posts: 1,544
went to the track and not too happy---HELP

alright here is my best run of the night last night

R/T .532
60 1.767
330 5.481
1/8 8.594
MPH 78.64
1000 11.303
1/4 13.587
MPH 98.96


Alright it did spin some off the line, but why is my trap speed and time so low. I was thinking that i should be more around 13.1-13.3. It feels like when i get up higher the engine is not pulling at all.........the cars just start pulling from me half way down the track. I am thinking my springs are really worn out and i am getting valve float. That is the only think i can think off. With that 60' time though i would think i would be pulling down some better numbers than almost a 13.6 @98.96. What do you guys think. Anyone have a car close to mine that could post a time slip so i can see how it pulls up top....I think i am losing a lot up top.
"White Knight" is offline  
Old 09-23-2004, 10:05 AM
  #2  
Registered User
 
WS Sick's Avatar
 
Join Date: Dec 2003
Location: Oklahoma where trees are made of wood.
Posts: 2,725
Re: went to the track and not too happy---HELP

Yep your MPH is more like a bone stock LT1 cars mph. Is yor fuel pressure strong all the way? Springs could do that. Is there any audible floating?
WS Sick is offline  
Old 09-23-2004, 10:08 AM
  #3  
Registered User
 
'94 Bad A Z28's Avatar
 
Join Date: Jan 2001
Location: Orlando,Fl
Posts: 2,905
Re: went to the track and not too happy---HELP

Awesome 60'.
'94 Bad A Z28 is offline  
Old 09-23-2004, 10:12 AM
  #4  
Registered User
 
WS Sick's Avatar
 
Join Date: Dec 2003
Location: Oklahoma where trees are made of wood.
Posts: 2,725
Re: went to the track and not too happy---HELP

I was just thinking, do you keep your foot in it till about 20 feet after the finish line? The mph measurement here is taken before and after the finish line then averaged.
WS Sick is offline  
Old 09-23-2004, 10:22 AM
  #5  
Registered User
Thread Starter
 
"White Knight"'s Avatar
 
Join Date: Nov 2002
Location: Michigan
Posts: 1,544
Re: went to the track and not too happy---HELP

I let off when i see the little light go on, on the side of the track--i think that indicates it's done reading. I'll try holding it even longer next time--but i am sure i have it down the whole way.

I am not sure about the fuel pressure, hasn't been checked in a couple years.
"White Knight" is offline  
Old 09-23-2004, 10:28 AM
  #6  
Registered User
Thread Starter
 
"White Knight"'s Avatar
 
Join Date: Nov 2002
Location: Michigan
Posts: 1,544
Re: went to the track and not too happy---HELP

can you actually hear valve float? This car has always had problems up top ever since i have got it. Ran 14.5's with exhaust and intake. that was with a good 2.06 60' I have never figured it out, but i am going to figure this out. I figure i will figure it out sooner or later.......hopefully sooner.

What should fuel pressure be? I might go buy a pressure checker and see if it's about right.
"White Knight" is offline  
Old 09-23-2004, 10:28 AM
  #7  
Registered User
 
chrism400's Avatar
 
Join Date: Jun 2003
Location: Dayton, OH
Posts: 890
Re: went to the track and not too happy---HELP

You are really launching well, but your 1/8 mile speed is about 3-4 mph low. I would definitely put some new valvesprings on it. The stock ones even when new only had 80 lbs at the seat. These lifters seem to like the 612 springs that CMS sells that put about 135 at the seat. These should really help your high rpm power. Fuel pressure is possible like the above post suggested. These fuel pumps seem to die a slow death. Mine was putting out 22 lbs when I realized it was the problem. When I put the Walbro 255 pump on, I gained 4 tenths and 3 mph! The fuel pressure check is super simple and takes about 10 min. Go to a garage and offer to buy them pizzas or something if they check it for you. The only other thing I can think of would be if your engine is pulling timing for some reason. I didn't see that you had the lt4 knock module in your sig. Maybe you do and I didn't see it. If you are running roller rockers, you Have to have this module.
chrism400 is offline  
Old 09-23-2004, 10:29 AM
  #8  
Registered User
 
warbird27's Avatar
 
Join Date: Mar 2004
Location: BV, PA
Posts: 109
Re: went to the track and not too happy---HELP

i have that same problem. last time i was at the track, i went 13.77 w/ a 2.0 60' and .533 reaction time. my car accelerates great until i think my 3rd kicks in and then it feels like it isn't pulling at all.
warbird27 is offline  
Old 09-23-2004, 10:50 AM
  #9  
Registered User
 
WS Sick's Avatar
 
Join Date: Dec 2003
Location: Oklahoma where trees are made of wood.
Posts: 2,725
Re: went to the track and not too happy---HELP

You'll only hear an audible valve float when the springs are in really bad shape. Yeah the headers can play havoc with knock sensors, get a scanner and run it and see how much knock youre seeing.
WS Sick is offline  
Old 09-23-2004, 11:03 AM
  #10  
Registered User
Thread Starter
 
"White Knight"'s Avatar
 
Join Date: Nov 2002
Location: Michigan
Posts: 1,544
Re: went to the track and not too happy---HELP

i have that same problem. last time i was at the track, i went 13.77 w/ a 2.0 60' and .533 reaction time. my car accelerates great until i think my 3rd kicks in and then it feels like it isn't pulling at all.
that makes me feel even worse about my top end. If i do the math that means if i was racing you i would be .233 seconds ahead of you at the 60' mark and would end up beating you by only .183 seconds. That means i'm losing 50thousands to you and you say yours is slow. Mine has always been like this so i guess i don't even know what it feels like. I don't even like it to spin up past 5grand--cause it feels like it's no going.

By the way, this thing is hard to hook up..........the cops think so too........been pulled over twice in one week.......and didn't mean to do it either time...the one was because i spun them and the other he said i accelerated too fast....it was half throttle. Plus that sand in the parking lots gets all over my Nittos and makes it even worse.

I wonder what i could get my 60' to with some suspension mods....right now it's stock suspension. The only good thing I have goind is the 60 in my opinion.
"White Knight" is offline  
Old 09-23-2004, 11:06 AM
  #11  
Registered User
Thread Starter
 
"White Knight"'s Avatar
 
Join Date: Nov 2002
Location: Michigan
Posts: 1,544
Re: went to the track and not too happy---HELP

I forgot to mention after you asked if i had one; I do have an LT4 knock module.
"White Knight" is offline  
Old 09-23-2004, 11:06 AM
  #12  
Registered User
 
Z95m6's Avatar
 
Join Date: Oct 2001
Location: newton, kansas, USA
Posts: 6,069
Re: went to the track and not too happy---HELP

whats the mileage on your car? My car is/was dying off in power up high. I think i fixed it with a new fuel pump. I still have some more testing to do before i'm sure its fixed.
Z95m6 is offline  
Old 09-23-2004, 11:08 AM
  #13  
Registered User
Thread Starter
 
"White Knight"'s Avatar
 
Join Date: Nov 2002
Location: Michigan
Posts: 1,544
Re: went to the track and not too happy---HELP

I think i just rolled over 126,000 miles
"White Knight" is offline  
Old 09-23-2004, 11:12 AM
  #14  
Registered User
 
Z95m6's Avatar
 
Join Date: Oct 2001
Location: newton, kansas, USA
Posts: 6,069
Re: went to the track and not too happy---HELP

I would check your fuel pressure.
Z95m6 is offline  
Old 09-23-2004, 02:56 PM
  #15  
Registered User
Thread Starter
 
"White Knight"'s Avatar
 
Join Date: Nov 2002
Location: Michigan
Posts: 1,544
Re: went to the track and not too happy---HELP

This is a time someone just posted....


2.23 60ft
5.95 330ft
9.04 1/8 ET
79.77 1/8 MPH
11.70 1000 ET
91.59 1000 MPH
13.94 1/4 ET
101.12 1/4 MPH


I have this 60' beat by like .5 and he ends up closing the gap to around .3 Now correct me if i am wrong .5 in the first 60' is quite signifigant, because you are going faster quicker(tenths in the first 60feet add up to a more signifigant e.t. drop). so that means in this example he is overcomming this advange that i have of it being in the first 60 feet and also closes the gap by .2. Is that not very signifigant loss of hp up top? I always thought it was in my head. And this is an almost bone stock car.
"White Knight" is offline  

Thread Tools
Search this Thread
Quick Reply: went to the track and not too happy---HELP



All times are GMT -5. The time now is 02:43 PM.