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View Full Version : 1/4 mile times slow why???



ZOOMBUGGY3
06-14-2005, 07:18 PM
whats up guys. its been a few months since i posted on the boards. i got a problem with my car and hopeing some one can help me out with it or point me in the right direction.

last year i went to the track all summer and could only run 14.89 at best and i knew the car could go faster but it felt like something was holding it back.

now this year i added my custom front mounted intercooler with the 3" pipes, raised sc top, adjustable fuel pressure regulator, 75mm throttle body, 76mm c&l maf, and relocated the filter in the fender well. raced it and could not break into the 14's at all beacuse i had major traction problems.

all my mods are listed below in my signature.
i am still runing the stock fuel injectors could i be maxing them babeis out and maybe need to up grade.

91BLOWNSC
06-14-2005, 07:26 PM
whats up guys. its been a few months since i posted on the boards. i got a problem with my car and hopeing some one can help me out with it or point me in the right direction.

last year i went to the track all summer and could only run 14.89 at best and i knew the car could go faster but it felt like something was holding it back.

now this year i added my custom front mounted intercooler with the 3" pipes, raised sc top, adjustable fuel pressure regulator, 75mm throttle body, 76mm c&l maf, and relocated the filter in the fender well. raced it and could not break into the 14's at all beacuse i had major traction problems.

all my mods are listed below in my signature.
i am still runing the stock fuel injectors could i be maxing them babeis out and maybe need to up grade.


Well how warm was it when you went and what were the conditions? When I went, My times varied from 15.8's to 14.8's. Depending on how hot my engine was, how hot the track was, and if the sun was beating down to heat the air up. Theres a lot to factor in.

ZOOMBUGGY3
06-14-2005, 07:33 PM
well when i ran the 14.89 last year it was steaming hot out side.

and this year so far its been nice and cool out

LightEMup
06-14-2005, 09:13 PM
well when i ran the 14.89 last year it was steaming hot out side.

and this year so far its been nice and cool out
uhh....not to be a dink or anything, but you didn't perchance gain ALOT of weight between track visits did you?? like...3....4 hundred pounds??? cuz that would do it :D

David Neibert
06-14-2005, 09:28 PM
How does your 1/4 mile MPH compare to last year ? Slower, same or faster ?

David

Jason Wild
06-14-2005, 09:29 PM
this is the key to your slower times
raced it and could not break into the 14's at all beacuse i had major traction problems that will not help your times at all.

LightEMup
06-14-2005, 10:05 PM
this is the key to your slower times that will not help your times at all.
yeah he's right...it's all about the launch and getting minimal wheel spin, i would sugjest a pair of slicks, or if you can't afford profile tires, slicks, or some sort of very sticky tire, try burning out for 15...20 seconds before lining up, that should get you a little more grip

SCme94
06-14-2005, 10:13 PM
Like David said....You need to compare your MPH from before and after to really see if you are making more or less power. This becomes even more important when you have spinning tires and a 5-speed. ET can change dramatically with just a little more tire spin or a slow shift.

Birdman93
06-14-2005, 10:31 PM
A 15-20 second burnout?? In street tires?? :eek:

When I first started racing at the track, and all I had was street hides, Mike Albee told me to avoid the water box and turn them over just a couple of revolutions to clean them off. Then when I was on the line I would hold the brake and bring the rpms up to just below the point where the tires started to break loose.

With this method and a stock 95 SC I hit a personal best of 15.146 @ 91.16-If I had been running slicks and a set of 3.55s I could have done better than that.

ZOOMBUGGY3
06-14-2005, 10:50 PM
litemup no i did not gain weight from last year.

dave neibert i dont have the slips in front of me right now but if i remember right they are a little slower then last year.

jason wild your right i know that wheel spin does not help but im starting to think that i might be max out the stock injectors i feel that with the mods i have i should be faster then what i am.

liteemup i was racing with my street tires 255-50-17's and i only spin them enough to clean them.

Jeremy_K
06-14-2005, 11:23 PM
litemup no i did not gain weight from last year.

dave neibert i dont have the slips in front of me right now but if i remember right they are a little slower then last year.

jason wild your right i know that wheel spin does not help but im starting to think that i might be max out the stock injectors i feel that with the mods i have i should be faster then what i am.

liteemup i was racing with my street tires 255-50-17's and i only spin them enough to clean them.
I have traction problems too (from doing too many 15-20 sec. burnouts :rolleyes: ) I lower my street tires to 15psi (rear) and i'll do one long burnout to soften the tires. then the tires will be sticky the rest of the night and i only do short burnouts to get the rocks off of them. long burnouts do nothing but heatsoak your IC and engine.

XR7Kurt
06-14-2005, 11:41 PM
60 ft. times and mph will tell you if it's traction, the power you're making, or a combination. You've changed so many things since last year it could be more than one thing. You could have leaks. How much boost are you making now?

Kurt

LightEMup
06-15-2005, 10:05 AM
yeah haha, i forgot to menchen the long burnouts are only good if u got the money to replace tires every week haha. But i usually do a long one at the beggining then short ones afterwards, at the 1/8 mile track we cycle through people pretty quick, so you get to race every few minutes. So the tires stay sticky for quite a few races

Big Cat Davo
06-15-2005, 10:25 AM
Long burnouts on street tires is not going to help the launch. When you heat a street tire it releases some of its natural oils, making the tire slick, not sticky. In addition the loss of these oils causes premature ageing on the tire, it will get hard and cracked a lot sooner than normal. A "burnout" on the street tires is only to make sure that they are clean and dry, nothing more.

Dave

007_SuperCoupe
06-15-2005, 11:18 AM
whats up guys. its been a few months since i posted on the boards. i got a problem with my car and hopeing some one can help me out with it or point me in the right direction.

last year i went to the track all summer and could only run 14.89 at best and i knew the car could go faster but it felt like something was holding it back.

now this year i added my custom front mounted intercooler with the 3" pipes, raised sc top, adjustable fuel pressure regulator, 75mm throttle body, 76mm c&l maf, and relocated the filter in the fender well. raced it and could not break into the 14's at all beacuse i had major traction problems.

all my mods are listed below in my signature.
i am still runing the stock fuel injectors could i be maxing them babeis out and maybe need to up grade.

Dumb question, but no one has asked it yet and it's not listed in your mods. do you have a tune? From looking at your mods, without a tune, you are more than likely running lean...if you've had these mods for a time now, you may be prematurely aging your spark plugs (i.e. melting them). I ran into that issue last year for me...baseline run before mods...15.0..add a few mods...15.2...add some more mods...15.5...turned out to be BAD plugs. They had gapped to nearly .080 and with my mods, I was blowing out what spark was there. Got new plugs, got a tune and now am much faster.

Just going back to the basics, since it isn't listed.

ZOOMBUGGY3
06-15-2005, 09:30 PM
xr7kurt i dont have my time slips in front of me right now.i know i dont have any leaks at all in the tubes. it took me a year in the making to make this custom front mount intercooler. and all testing with the tube were done to 30 psi.oh yah im runing about 10-11psi in boost.

i know about long burn outs on street tires relaes oils from tire. i only give them a quick spin just to clean them.

007-supercoupe if you are talking about a eec tuner no i dont have one. i do how ever have a air/fuel ratio guage on order so i can adjust the fuel pressure right. and *** far as the spark plugs i just changed them about 2 months ago. and the ones that i tok out were not melt they had normal wear and tear. they were in the car for about 2 years.

007_SuperCoupe
06-15-2005, 11:21 PM
No, I'm not talking an EEC tuner. I really don't think that you can manage too much with those, just because of the inherent limitations that they have. I was actually refering to an SCT chip.

Running 10-11 lbs of boost actually sounds like you are simply running out of supercharger. I don't have your mods in front of me now...anything done to the sc as far as porting goes?

I've actually seen a highly modded SC dyno about the same that I did with stock heads and cam, because there was not enough supercharger. A quick switch to an MPII and he was pulling 50 rwhp more than me then. Just another thought.

What are you typically running for A/F ratio? Just curious...another piece of the puzzle to see what's going on.

ZOOMBUGGY3
06-16-2005, 06:57 AM
007-supercoupe so the chip that they sell on supercoupe performance is better then the eec tuner?
and your saying im runing out of superchager because i was runing only 10-11 psi. i lost about 1-2psi when i installed the custom intercooler. no i dont have any porting done to the blower. i had to put my spare blower back on the car this winter.from when i did the timming chain cover gasket. i had a stock 89 blower all ported out but i cracked the case when i tried to reseal it.what happen was that the bolt hidrolocked when i was putting them back in i didnot realize that their was still some of the old silicon in the bolt holes. i plan on getting another bloer soon and porting it out.
i dont know what the air/fuel ratio is at right now i have a meter on order it should arive today some time.
do you think i should run a 10% pulley?

007_SuperCoupe
06-16-2005, 09:08 AM
A properly tunes SCT chip is much better than an EEC tuner. The SCT program can get to many tables that the EEC tuner can't. Kind of like putting a bandaid on a sucking chest wound. It doesn't really help it a lot.

I got another look at your mods...with ported heads (to what extent I'm not sure...oversized valves?) you may be running out of supercharger. One thing that I would definately check is for vacuum leaks. Basically you cap off the pcv valve and the crank case vent, then pressurize the intake system from just behind the filter. Check every joint with soapy water. I'd pressurize it to 20 psi, checking for leaks every 5 psi. That will find any and all leaks. That is the only way that I check for vacuum leaks on my SC. Most don't show up under vacuum conditions and starter fluid.

I don't think that you should go with a 10% until you check for vacuum leaks. Once you ensure that there are no leaks, then you can look at a smaller pulley.

And you definately need a tune to be running at optimal conditions. I personally recommend that you have Dave Dalke do the tuning. I had him tune my car with excellent results. He definately knows his stuff.

ZOOMBUGGY3
06-16-2005, 10:38 PM
the heads are ported and stock vavles. ill pressure test the system the way you told me.
i got my air/fuel ratio today so i can adjuste the fuel pressure the way the car needs it.
so what do you think about fuel injectors 42lbs out of a lincoln mark viii.
and would you recomend a 5% or a 10% pulley?

does dave dalke makes the custom chips. and what if i get a chip and i do more mods will that mean i need another chip after that

David Neibert
06-16-2005, 11:21 PM
the heads are ported and stock vavles. ill pressure test the system the way you told me.
i got my air/fuel ratio today so i can adjuste the fuel pressure the way the car needs it.
so what do you think about fuel injectors 42lbs out of a lincoln mark viii.
and would you recomend a 5% or a 10% pulley?

does dave dalke makes the custom chips. and what if i get a chip and i do more mods will that mean i need another chip after that

I hope your talking about a wide band o2 sensor and not one of those useless A/F ratio gauges that work off your stock o2 sensors. You also don't want to be making fuel pressure adjustments to control the A/F ratio. Set the pressure to 39-40 psi with the vacuum hose off and then use the tuner to adjust the A/F ratio.

If your going to use 42# injectors you will also need a MAF that is calibrated for that size. BTW, I can't imagine why a Mark VIII would have 42# injectors...I think they would normally use something much smaller like 19 or 24#

David

007_SuperCoupe
06-16-2005, 11:25 PM
You're probably close to needing injectors, so it wouldn't be a bad idea to get some larger ones. However, develope an end goal and get injectors to match. The 42 lb injectors will be fine for ported heads, MP supercharger, etc. If you plan to go with the AR, then look at least at 50lb injectors. (I don't think that a M8 has 42's...probably 24's at most)

I think that the pulley will be determined by how high your intake temps are. If your IC is really good, then go with a 10%, but if it isn't cooling your intake down, then I wouldn't go with more than a 5% pulley. Chances are you'll be able to go with a 10% though...or a 5% and a 5% jack-shaft pulley, which is what I would do.

As far as Dave Dalke goes, he does burn custom chips. The BEST way to get one is at a dyno tune. If you just do a mail order type chip, he can get it running safely, but not really optimally. That requires a dyno. As far as later mods after a tune, all you have to do is get the chip re-burned. I think Dave D. charges around $50 for a reburn. But you do not have to purchase another chip.

ZOOMBUGGY3
06-17-2005, 10:03 PM
the mark viii do have 42lbs injectors (green top) i found that out here on the forums.and i seen them in the junk yard with them.
the intercooler works very well so ill get a 10% pulley.
well ill be going to the track this wensday so ill keep you guys posted.