M/T DRs at the track....
 

Ok so Im putting the MT DRs on soon. 275/40/17 I have an extra pair of bullitt wheels im putting them on for when I go to the track. I am wondering what rpms I need to launch at to keep the rear from snapping? What Psi do people run in those? I plan on doing full burnouts unless it is just too much bite. Any special driving methods with these? I plan on revving to 2500 and dumping the clutch.

im pretty sure you wont spin doing a 2500 launch....the M/T Drag Radials are pretty good, but a buddy of mine was still spinning em with 5k launches,but if you dont plan on a 5k launch they should hold up pretty good.

The rear end isn't going to "snap". Just get a good smooth consistent launch. I see most guys using 18-22psi but I've learned to ignore most guys.

i wouldnt go past 1500 rpm or you are asking for trouble. Good thing that happens though is you usually destroy the carrier housing as well.

Remember, when you snap your axles, stop instantly and wait to clean up the mess instead of dragging it down the 1350. People like me dont like to wait for a 30 minute cleanup.
:tongueout:

well if they do snap thatll just be a reason to need a new rear. Might as well throw in the good stuff so I can launch at 5k.

a 5000 rpm launch and you can pretty much guarantee that youll be revving but not going anywhere.
:tongueout:

Put it this way, i had a 2step set at 3500 and i still bogged coming out of the hole. also stock gear, so take that into consideration. id say right around 3-4k depending on gear. when you heat these right they will straight hook! enjoy:)

well, i use to run Nittos in that size.. but your car is a lot different than mine. I launched at about 2800 rpms with a 1.90 60ft.. i think you're just gonna have to figure out what works best for you

Youll need to launch at 4k+ to keep from bogging. A 1500 launch will bog like hell.

I tried Nittos once and they were better than street tires, but just didnt perform as I expected at the track like a good DR. These are just for the track so im not too worried about the softer compound not lasting.

Launch around 4500-5000. Anything less you WILL bog down horribly...been there done that and it's not fun. Run the tire pressure around 12psi, they will hook great. As far as reving it up and dumping it...you WILL break something then since they have a good bite to them. You need to PRE-load your car...start coming out on the clutch till it starts to grab..they way you already have the pressure on the axles..There will be less strain on them with the pressure already there then just suddenly grabbing hard as it would do dumping it. Do a burnout enough till you get a good amount of smoke going...no need for a monster burnout, you'de just be wasting tire then.

Yes I thik ill try revving to 4500 and slipping the clutch out. Cant find out till the track opens though. Hoping to cut better than my normal 2.0 60fts.

if you plan on launching at 4500+ like all these people are recommending, you will be walking home.

...oh yeah i should of added that my buddy has a built rear-end...31-splines,eaton carrier,etc....so he dont mind reving up to 5k and dumping the clutch.

its just gonna spin you need to get down to a 15" rim if you really wanna hook. I have been running nitto drags for years on nitrous drag racing etc... stock rear end. there just isnt enough sidewall or bite to get them to hook hard. Granted it happens, but its pretty rare with that size tire.

If you pre-load the car you will not have a problem with the rear. I launched at 5k on a STOCK rear with stock gears on ET street's and never had a problem and drove the car everyday to work. Even launched it on the street the same way. If you just rev the car and side step the clutch...yea you will be walkin home then no doubt. BTW that was launching on a 125shot out the hole!

The 40series tire is rather small but the Mickey's and BFG's are soft enough to wrinckle and hook pretty well. The MT's have alot more bite than BFG's for sure if they are at a resonably low pressure allowing for them to wrinkle the sidewall.

4500 preloaded launch on 10-12psi and you will be happy and have some good 60' times.

Yes I am going to try 4000 and slip it out slowly like Blk02stang said. I wont just dump it. If I dumped it wouldnt they spin anyways on about 5-6psi of boost at 4000? Ill be heading up to the 1/8th mile on the 31st. They just reconstructed the track there and its all brand new concrete. Should be hooking.

yeah you want to keep the rpms up atleast 3,500 at the lowest if you wanna get some power and not bog. its takes some getting used to but you will learn to ride the clutch and gas out.

Amazed that I haven't heard anyone mention that some of it depends on how well the track is prepared. On our Wednesday night test n tunes they usually don't prep the track to well. My first night out w/the car and not knowing what the track would do I launched at 20psi in the tires and 2800rpm. DEAD HOOK. Run two. 20psi and 3200,,DEAD HOOK. Run three 19psi and 4000rpm launch sidestepping the cluch and it spun the first 20 ft. It's a guessing game/launch technique/tire psi selection thing. You will figure it out. Practice, practice practice.