EST 1/4 mile time with stroker

Hey guys i just saw a video (http://www.qwkjeep.com/QWKJEEP/index.html)
of a jeep without a stroker running a 13.95 and beating a stock mustang (HAHA). you see his specs all he is running is 100 shot of nitrous and some bolt on stuff. If he can get those numbers what is your guys opinion about what my jeep can run. here is what i have done so far.
1995 Jeep Cherokee Sport 4 Door
Accurate Power 4.7 stroker
Extrude honed 00 grand cherokee intake
63mm T/B
Dana 44 with locker and 4.56 gears
Aisin Warner AW4 auto with full race prep (racing V/B eagle performance clutch packs and basket)
SYE and Tom woods D/S
double roller timing set
port and polished head
Borla Header thru to tail pipe no cat
heavy duty 3core all brass radiator
Hesco hi flow water pump
all electric fans (no clutch fan)
1999 cherokee under hood harness swap
(waiting to have AJAX motorsports tune the new comp)
alright thats it!!!
Any one have any ballpark figures on 1/4 mile
still have stock suspension with 2 inch spacer and 31x10.50 dunlop mud rovers
Thanks and good wheeling!! :repair:

It's not a stroker. A 50 shot would do it for you.

1) you have larger tires
2) you have better gearing to compensate
3) No nitrous
4) lots of work to get better flow

I'd guess with stock height tires, you'd pull 13's as well.

How does it feel relative to stock?

Can you go see for yourself at a track?

mid -high 14's

and really why? are you planing to make a sleeper to beat some civics ?

QWKJEEP is hitting the 100 shot after third gear only and he's still pulling in those timeslip numbers. Very good 60 ft times.

I don't know of any strokered XJ without power adders that's running 13's yet. My 4.6 stroker XJ ran a [email protected] in October with 142lb of weight reduction and no power adders.

http://www.dragtruk.com/ENTRIES/A9DFB5LA1GZW.html

If I had exceptionally good traction and 30 degree weather with a high barometer reading, maybe I could run a 13.99.
In normal street trim it ran a [email protected] in September.

LS1Jeep said:

mid -high 14's

and really why? are you planing to make a sleeper to beat some civics ?

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that about the only reason i want my jeep fast! never been smoked at the line, just when the ricers want to mess with me on the highway, then i have no chance. xjs kinda loose some accel after 65. have to be going <55 to get the aw4 to kick into 2nd for any decent accel. manually 2nd looses power at 65-70 anyways. (no tach)

just spray it....problem solved....

and the only reason qwkjeep is in the 13's is because of his great 60' and 330' times....his mph is really low for that E.T.

N20Jeep said:

just spray it....problem solved....

and the only reason qwkjeep is in the 13's is because of his great 60' and 330' times....his mph is really low for that E.T.

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60' in 1.79 is outstanding if he's on street tires. MPH is definately low, he should be pushing high 90's low 100's. It's like when a top fueler breaks after 100 feet, and then coasts to a 10.20 at 88mph. It's all about grip and moving from a standstill.

Mark

markw said:

60' in 1.79 is outstanding if he's on street tires. MPH is definately low, he should be pushing high 90's low 100's. It's like when a top fueler breaks after 100 feet, and then coasts to a 10.20 at 88mph. It's all about grip and moving from a standstill.

Mark

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well....his mph will always seem low because of his tranny gearing and Box-like shape....

ok guys its unoffical of course but after several runs at the locally manufactured track here in Yuma It was rolling off super constistant 13.60(not accurate probably 13.90 or 14.00) but i was using 28 inch tall street tires on it and having to feather the throttle or else it would just smoke them. after several runs and tuning it was super consistant so hopefully in a month or so i can take it to Phoenix International Raceway and get some real numbers. I think I am going to put the 125hp Hesco Nitrous kit on it first so i can run it without it then try a couple with it. I think that I will buy some extra wide street tires to help it hook up better. Well go to get back to tuning.

:repair:

1995kamikazeXJ said:

ok guys its unoffical of course but after several runs at the locally manufactured track here in Yuma It was rolling off super constistant 13.60(not accurate probably 13.90 or 14.00) but i was using 28 inch tall street tires on it and having to feather the throttle or else it would just smoke them. after several runs and tuning it was super consistant so hopefully in a month or so i can take it to Phoenix International Raceway and get some real numbers. I think I am going to put the 125hp Hesco Nitrous kit on it first so i can run it without it then try a couple with it. I think that I will buy some extra wide street tires to help it hook up better. Well go to get back to tuning.

:repair:

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you're out in Yuma? i just drove back today from there. you goto Gordon's or somewhere for the new year? we spent the day at Algodones in mexico, pretty fun stuff.

N20Jeep said:

well....his mph will always seem low because of his tranny gearing and Box-like shape....

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traction

XJ Saga said:

QWKJEEP is hitting the 100 shot after third gear only and he's still pulling in those timeslip numbers. Very good 60 ft times.

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QWKJEEP has very good 60' times. Looking at the 60' improvement, from when the first mid-14 sec times were posted (from mid-16's, to mid-14's on the bottle), and the current best 60' numbers tell a tale that the N2O is now probably engaged much sooner than 3rd gear.

With the stock 3.55 gearing I would expect QWKJEEP never shifts into the OD 4th on the track. The top end speed numbers also reflect the torque converter is probably not locking up (a manual solenoid switch override will help the trap speed).

As it is, the sub-14 times and 90mph trap speed reflect somewhere around 260 rear wheel horsepower (given the XJ weight, aero drag, and frontal area). The engine with the mod's listed is probably good unassisted for 170 rear wheel hp, so the N2O shot is doing considerable work. Good ET's (even the low 16's without the bottle) for a 3.55 geared 4.0L XJ. 4.56 gears would probably help it pull mid-14's without the bottle and mid-13's with the assist. The unknown is if the XJ could pull enough rpm for 100 mph in 3rd (a tire size exercise), as a shift into OD 4th is likely to slow down the ET and trap speed.

1995kamikazeXJ, you sould see clean mid to low 14-second ET's with good air and good traction. The desert does not always afford the best air quality (too dry). The same gearing/tire size issue will need attention. With the N2O shot target ~105 mph in 1:1 3rd gear, with 3% TC slip at 4800-5000 rpm. Find a tire size speed gearing calculator to help out with what height tires to bring. This should get you well under a 14-second ET if you can keep it in 3rd gear through the lights.

For comparison one of my old V8 cars runs 14.00-second ET's at 101-mph (stock drivetrain with 4.10 gears and 215/75 whitewalls). This car is ~3200# and does not make the same fast 60' times as QWKJEEP's (too much clutch work and wheel spin with the skinny 215's).

Keep us up to date on the progress.

Dr. Dyno said:

I don't know of any strokered XJ without power adders that's running 13's yet. My 4.6 stroker XJ ran a [email protected] in October with 142lb of weight reduction and no power adders.

http://www.dragtruk.com/ENTRIES/A9DFB5LA1GZW.html

If I had exceptionally good traction and 30 degree weather with a high barometer reading, maybe I could run a 13.99.
In normal street trim it ran a [email protected] in September.

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Hey Dino,
According to the calculator at Golen engines website thats 235.818 rwh in the 1/4, 236.17 in the eighth. I bet a set of 3.55's and fixing the rev limiter would get you there, or awful close. Having it fall flat on top hurts. Thinking about it, with musclecars a lot of the drag guys (like me) remove the swaybar for faster weight transfer. A set of quick disconnects might trim your 60ft time quite a bit...

I wish I had known there was a dragstrip in the UAE when I was there for 6 months in 2001. Would have made time pass quicker. I really liked it there anyway though.

Randy

A set of 3.55's won't help me. I hit the rev limiter at 95mph in 3rd gear (speedo shows 100mph) with the tach showing 5150rpm so by switching from 3.07's to 3.55's, I'd have to change to 4th well before the 1/4 mile trap. Raising the rev limiter (almost impossible on OBD I XJ's) would help my trap speed somewhat because I could stay in 3rd for longer. The engine's still smooth and pulls hard at 5000+rpm (doesn't fall flat) so it can definitely use more revs (at least 5400). Does anyone know how to disable the rev limiter altogether?
I did think about a set of quick disconnects for the front swaybar to aid weight transfer to the rear during launch and that's a good idea. That way I can keep the swaybar functional when I'm running on the street.
The SmokemUp website's HP calculator based on 1/8 mile trap speed (the most accurate that I've come across) yields a figure of 221rwhp for my stroker and I think that's more realistic than the 236 flywheel HP figure from Golen's site.

Ed A. Stevens said:

For comparison one of my old V8 cars runs 14.00-second ET's at 101-mph (stock drivetrain with 4.10 gears and 215/75 whitewalls). This car is ~3200# and does not make the same fast 60' times as QWKJEEP's (too much clutch work and wheel spin with the skinny 215's).

Keep us up to date on the progress.

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There was some great article somewhere, written by an engineer who put a twin-turbo'd 302 or 351 into his 67/68 Mustang. He wrote an article stating that tire size has nowhere near the effect on traction as we'd think it does, and made a great case for it. Basically, he says, it's all about the car's (read: the chassis and suspension's) ability to plant, and keep, G-forces on the tires.

I think I found it by searching for "Twin Turbo 351" on Google or Yahoo.

Pretty awsome times...60ft in the 1.70 range..wow..at least to a old fart like me....in the old days...13's were hard to come by in a streetable car. I would think that it's the aero part that makes it hard to go really fast in a XJ...

If you are gonna run Nitrous....get a leakdown tester...run a baseline and monitor it over time. You may find some real suprises....and find someone (if you don't already know) that can read plugs...i mean REALLY read plugs. And remember there is no such thing as too much octane in a Nitrous motor. Nitrous likes a load too...If it was me, i'd time it in at 1/2 second out in series with a window switch set at 3500 rpm low event and 5500 high event.

I don't care if it took him a week....he beat a 'Pony (woo-hoo)....the guy must have been pi$$ed, beat by a Jeep, bet he had his tail between his legs on the ride home....lol.

krakhedd said:

There was some great article somewhere, written by an engineer who put a twin-turbo'd 302 or 351 into his 67/68 Mustang. He wrote an article stating that tire size has nowhere near the effect on traction as we'd think it does, and made a great case for it. Basically, he says, it's all about the car's (read: the chassis and suspension's) ability to plant, and keep, G-forces on the tires.

I think I found it by searching for "Twin Turbo 351" on Google or Yahoo.

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I would be careful about claims disregarding tires and traction (along the lines of the article mentioned, unless you have nothing to lose). The critical words are "nearly" and "as we," if you include yourself in the "we" who believe in his thinking.

In high school and college physics they teach that traction is a function of the friction coefficient and force at the traction patch (the chassis's ability to plant the tires), and the surface area of the traction patch contact is not even part of the equation (the tire size or tread pattern is not considered important). The difference between a large and small tire or grooved and smooth tread is not part of the physics equation. The result is a long-standing theory that tire size is not very important in achieving quality traction. This was conventional thinking until the mid-1960's, when the overwhelming data complied by winning racers forced a few Engineers & Scientists to rethink what the physics books predicted.

In upper-division Engineering you learn the coefficient of friction (Cf) for a material is found by identifying and isolating the surface area of the contact patch, and knowing the force and power transferred. The Cf is found by measuring the belt width and wrap length on a pulley, or the length and width of the tire contact patch, and plugging it into the standard physics equation. Wider belts and wider tires always produce a superior friction coefficient, as does smooth belts and smooth tread patterns (given equal applied force, rubber compounds, and an equal finish mating surface for the pulley or road). This style of research lead competition away from tall skinny tires to “wide-oval” low & wide profile racing tires and slick tread styles that advanced track racing performance over previous design theories (and is still proven today).

While the traditional physics equation is simple and correct, and does not involve the tire size or tread style, or that the Cf is directly impacted by the characteristics of the mating surface area. The equation to reflect the true action in nature (the goal of scientific modeling) is much more complex than the old physics prediction for the power transferred knowing only the Cf and applied force. Expand the mathematical model representing the Cf and you will include the tire size and tread style (dominant factors influencing the Cf, along with rubber compound and tire construction).

If you (or a friend) still believe tire size or tread design have zero influence on traction, I offer to race your favorite wheel driven vehicle against mine at a drag strip for ownership titles … as long as I get to choose your tires, and my tires.