Drag Racing Tech - MT drag radial tips




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Iceman02
07-14-2012, 09:54 AM
Hi fellas,

Got a chance to run the new 275/60/15s last night. The car on its best run had the front QA1s on "1" and the rear drivers at "6" and passenger rear set at "7". The best 60ft I could muster all night was a 1.99 (horrible). Watching the video, i had hard tire spin for about 25ft.
The car has absolutely no wheelhop, just steady smooth burn on launch.
I made four runs with tire pressure starting at 18 and going down to 16lbs on my last run. I did a very healthy burnout on each and launched at 5000rpm.
When the tires did bite, there was no bog and the car hit pretty decent.
The best time slip was:
1.99 60ft
8.15 1/8th mile @ 88.5 mph
12.56 ET @ 112.05 mph

The top end is pulling good, if I can get this 60ft squared away, I might be able to whittle this ET down quite a bit more.

Thanks


6SSPEED
07-14-2012, 11:56 AM
Im sure there are better people out there to answer the question but my recommendation would be adjusting pinion angle or maybe some relocation brackets for the lca's. Could the frontend be comming up too fast, possibly unloading the rear tires?

Iceman02
07-14-2012, 12:27 PM
The front shocks come up fairly quick and hang high coming down slow. The 9" has relocation LCA brackets and pinion angle is -2 degrees. I'm wondering if setting the back shocks significantly stiffer will help much. Maybe combining that with 14lbs in the tires might do the trick.


fenton06
07-14-2012, 12:33 PM
Lowering the PSI any more won't help I don't think. Radials really like stiff rear shock settings, are they hooking then unloading?

Might to too much burnout as well, heat them up til they grab and chirp and that's it. Look at some of the x275 videos on the net.

transbird95
07-14-2012, 12:48 PM
I run mt 275/60/15s as well and my shock settings are about where yours are. I only do 3-5 second dust off burnouts at the track and get 1.5 sixty foot times. Tire pressure is 16-17lbs. How was the track prep? On the street legal nights where I live they don't prep the track at all. I am still having troubles hooking then, but on a race weekend it grabs nice.

Iceman02
07-14-2012, 02:32 PM
Track prep was limited because it was a test n tune night. I might have to go back on a Saturday night when they have competitive brackets to see if I fare any better.
The tires didn't grab then unload, just spun fast and hard and then grabbed. Problem was, that spinning was half way to the 60ft marker lol.
I figured because they didn't grab and unload, that my suspension had to be close. The front was still transferring pretty well when they did hook finally. I'm just trying to get in the 1.6- 1.7ish range on my 60ft. That...and some good air will let me close in on the 11.99 bubble.

Spellbound
07-14-2012, 04:03 PM
I notice you're a M6, I never had good results using a DR on my old set ups with the M6.

Anyway, with my current car, with the MT DR, it likes the Hal's set on "boob slayer" <girlfriends term for when I forget to set shocks back to street setting, which would be 8 on both sides. Her car likes the shocks hard too, lol.

NHRAFORMULA00
07-14-2012, 07:41 PM
You need to lower your launch RPM untill you can hook,it all depends on track prep. Bad prep maybe 4,000 rpm. Good prep 5500-6000 rpm. DR need 19-20 psi for best results. Do a burnout on the street and you will see an under pressured DR will leave marks on the outer side of the tires, bump up the pressure until it looks even across the tire.

Fbodyjunkie06
07-14-2012, 11:15 PM
I notice you're a M6, I never had good results using a DR on my old set ups with the M6.

Anyway, with my current car, with the MT DR, it likes the Hal's set on "boob slayer" <girlfriends term for when I forget to set shocks back to street setting, which would be 8 on both sides. Her car likes the shocks hard too, lol.

This it's never going to hook like you want on radials.

Clutch cars HAVE to have wheel speed and slip off the line which a drag radial CANNOT have. Radial has to stay dead hooked and you're never going to get that with a clutch.

Sorry if this bursts your bubble.

Demonicbird00
07-15-2012, 08:47 AM
you need more gear, at least 4.30s

radials can work w/ 6spds you just have to spend the time tuning the suspension

-brandon

Iceman02
07-15-2012, 02:36 PM
^ I was looking at 4.30s too. That would put me right around 6k through the lights as well right now. I know DRs arent as desirable as a slick with a manual. But, because of my occupation....and that i drive this car on the street several times a week, I wanna go as fast as I can go on these.
I think with 4.30s I might be able to launch at 4k instead and shock the car (tires) a bit less too.

dans94z28
07-15-2012, 03:36 PM
not sure how drag radials are but after a burn out with street tires a small dry hop ofter to scrub the tires always has helped my street tires hook. if i dont they always just spin.

Demonicbird00
07-15-2012, 04:27 PM
Or just go down to a 26" tire and leave the gear alone

fenton06
07-15-2012, 04:32 PM
Missed the fact you had an M6... good luck with the radial!

cantfind2nd
07-15-2012, 04:44 PM
why would he want more gear if hes not hooking? i have 4.30s m6 car 440 rwhp it has and never will hook up on a 275 60 15 dr. ive tried everything , adjustments , driving style... just buy slicks.

slow67
07-15-2012, 04:57 PM
This it's never going to hook like you want on radials.

Clutch cars HAVE to have wheel speed and slip off the line which a drag radial CANNOT have. Radial has to stay dead hooked and you're never going to get that with a clutch.

Sorry if this bursts your bubble.

Unless you have a slipper clutch.

Iceman02
07-15-2012, 06:47 PM
I guess I will get all the life out of these I can (probably till next spring), and then save up some $ and get some spare 28x10 slicks. I still think I will see high 11s eventually.....just not consistently.

Fbodyjunkie06
07-15-2012, 07:48 PM
You'd have to put a lot of slip in the clutch.... You'd toast that thing fast to put enough slip in to have it work right. Not worth it... Better off just putting a slick on with a stick car... Chances of getting it right, and repeatable is about zero.

Thank you for backing up my post.

DR's and clutches just don't go together.

If they hook it will bog so much it's going to pull the poor thing completely out of it's power band and/or break shit.

Then if you tried slipping the clutch enough to make it not bog it will toast the clutch.

Even a slipper clutch would be hard to get right on a radial and even then it's not what a clutch car needs.

Demonicbird00
07-15-2012, 09:04 PM
why are you set on 28" tires? your gear/tire setup is wrong, cheapest and easiest way out is 26"

maybe im doing something wrong/right but i hook on my DRs

-brandon

Iceman02
07-15-2012, 09:54 PM
I went with 28"s because they have a better footprint, and next year I planned on more intake mods and spraying. The 2" taller tire would allow for more mph with the 3.90 gear the car currently has. Until I spray, the cheapest and easiest way for me to get the ideal gear this summer yet is to change ring and pinions. I have a 4.11 available but have entertained a 4.30.
Ford 9"s are a breeze to work on, changing gears is easy. If I put 4.30s on this Detroit Locker unit, I will pick up a spool to re-use the 3.90s on at a later date with more power. Spools aren't any worse driving on the street than a Locker is......unless its raining (which ya shouldnt be out in anyway). My Plymouth had a spool, and I swear it wasn't as "noticeable" as a Locker.
Obviously, I will need slicks with more power. I just really thought that with the low power I have now, DR's would have had a fighting chance. Now its my goal to hit a 11.99 with them before they wear out just to say I did, and then move on to bigger, better, and faster things.
I guess the point of this post was to see if my launch rpm, tire psi, and shock settings were in the right ballpark. I'm not super familiar with these cars. My last car had Cal-Tracs and monoleafs and was a cinch to dial in.
Outside of that, going faster is just some more $s down the road, the car's ready for it.... and going from a 9second Nostalgia Super Stock car to a 12/high 11 second street car is cheaper but just as challenging to make things work.

TurboStangJON
07-15-2012, 10:59 PM
you need more gear, at least 4.30s

radials can work w/ 6spds you just have to spend the time tuning the suspension

-brandon

Can you elaborate on what needs to be done suspension wise in order to get a manual car to work on a radial.

Demonicbird00
07-16-2012, 08:12 PM
i have qa1s w/ a 275 spring up front and qa1s in the rear w/ a stock spring,wolfe drag bar sfc,phb,lcas,adj ta and bmr ta mount

standard setup w/ the settings in the front and rear 1-3 in front 7-8 in the rears

1.49s-1.55s 60's. i plan to have a local suspension guy come to track and fine tune the suspension, theres no reason why i cant run 1.38-1.41s consistently

launch rpm varies due to prep

subarubill96
07-16-2012, 08:59 PM
:eek2::punch:

TurboStangJON
07-16-2012, 11:43 PM
i have qa1s w/ a 275 spring up front and qa1s in the rear w/ a stock spring,wolfe drag bar sfc,phb,lcas,adj ta and bmr ta mount

standard setup w/ the settings in the front and rear 1-3 in front 7-8 in the rears

1.49s-1.55s 60's. i plan to have a local suspension guy come to track and fine tune the suspension, theres no reason why i cant run 1.38-1.41s consistently

launch rpm varies due to prep

I think you just named every run of the mill suspension part on an F-body. Getting a radial to work on a stick car is more than shock settings and launch RPM.

Fbodyjunkie06
07-17-2012, 12:25 AM
Demonic, it's time to stop talking and prove this to us, I want to see, your car, run a sub 1.38 or better 60 foot time, and not have a traction after the 60 foot, 10 runs in a row... anything less then that, is not repeating as far as any real racer is concerned.

If you do that then I will change my tune that you can get a radial to work with a stick and without a slipper clutch.


Get it done, or stop talking.


BOOOO YA! That just happened.....seriously....it did.

Sorry OP.

I think you can make it work somewhat for what you're doing right now, but when they wear out get you a set of 28x10.50 stiff sidewall ET Drags and then you will really be happy with your track times and consistency. I feel like I'm being the bearer of bad news, but just trying to get you everything you can out of your car!!!:)

BTW if Demonics car doesn't bog and buck like a cattle prodded mule on those runs I'll paypal him 100 bucks.

Video proof will be needed to confirm.

studderin
07-17-2012, 05:27 PM
haha 10 runs, in one day with a M6 car! even getting 1.60 thats hard, I dont think I would do that to my car. maybe if I spent like 12 hours at the track... thats alot of runs to get it.

Iceman02
07-18-2012, 09:08 AM
It would be a push to get 5 runs where I'm stuck racing. Anyway, thanks to everyone for throwing their two cents in. I'm putting in 4.56 gears in the next week. I watched the videos of my runs. The suspension is working okay, but the wheel speed in 1st sucks. 3.90s arent nearly enough gear with an MS3 and 28" tires
......not naturally aspirated anyway. I've got a heavy car to get moving and I think the lower gears will get that wheel speed moving sooner.
In my experience a heavier car needs a bit more gear, especially one that's low on torque like this one. I should be going through the lights between 6100-6300, which is fine with me based on my power curve.
Thanks again.
Oh.........Demonic, if you get to where you're running 1.38's with an M6 and drag radials please share. I've actually run 1.38s in a 45+yr old car before. I remember how much power, converter, traction, and tuning it took. If you can, more power to you, but please share if you do.

wantsum410
07-18-2012, 10:54 AM
Did I read that right ...you are runnin a Magic Stck 3 ? If so that cam sucks at low end trq in a stick car.I ran it for 5 yrs & went CRAZY tryin to make good runs , I had some just not like it should have .
I finally had Pat G spec me a dif cam & am getting ready for some new passes.

Iceman02
07-18-2012, 12:38 PM
Yep, I've got a MS3 in a little cubed, low torque motor :). There's not much torque below 4 grand, but believe it or not I drive this thing regularly on the street. This is a little baby cam compared to my last monster (286 degrees @.050 and 740lb valvesprings).
4.56 gears, some good air and crazy flat foot shifting and I can smell high 11s.

Nemesis350
07-18-2012, 03:09 PM
The car will bog, buck, wheel hop, spin 30 feet out, blow the tires off, etc. That's what radials and stick cars, without a slipper clutch do. Period, end of discussion.

Definitely describes my car LOL But in all honesty i just figured it was because i don't have my suspension "set" in any way.

I have essentially the same setup as the OP, minus a strong rear, averaging the same times. So I do also appreciate all the info i'm seeing her in this thread (even if some don't agree with others)

Iceman02
07-18-2012, 04:36 PM
4.56 and a set of ET drags and you can do it right now.

I know, I know :). Hmmmm, okay.... anyone in the Chicago area or closer who wants to trade a set of newer ET Drags (28-10.5-15s) straight up for a set of 275/60 ET streets? They have 4 passes on them and were purchased late June of this year?
Maybe it will be easier to just focus on driving and killing the light than wondering how far I will spin........