Let me narrow my comment to drag racing only. Road racers or street racers would be the only ones foolish enough to put that kind of money in an IRS that weighs 125lbs. more than the 8.8 straight axle.
FRPP 4:10s and Traction Loc
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Let me narrow my comment to drag racing only. Road racers or street racers would be the only ones foolish enough to put that kind of money in an IRS that weighs 125lbs. more than the 8.8 straight axle.
ILLS
Dedicated LVC Member
I know quite a few people who dragrace their Cobra's and do not swap to solid rears even when running full slicks at a well prepped track. I have friends who have Cobra's I have done work on and most have not swapped from their IRS to solid. On one particular local SVT site I am a part of there are mostly terminator owners on there. Most are running anywhere from 425-600rwhp through the IRS varying from bone stock IRS to the DSS equipment being added. Very very few swap to solid rear until they go with a Big 2.8H KB, Whipple 3.3 or a turbo system. That goes for many many other people not on that site as well. There are very few Cobra owners that swap to solid rears. And of the few that do, they usually swap with a Mustang GT owner for their solid rear. The GT owner gets an IRS and the Cobra owner get the solid rear setup. That means no leftover parts. You show me one Terminator owner running 600rwhp or less and a solid rear and I will show you 75 more that are running their IRS at the strip.
JES_LS
Dedicated LVC Member
Okay so I'll ask the loaded question then.
If I can find a cobra irs for less than a mark's irs, is there any reason I should not go for it?
I'm looking to do a lsd swap into my current ls (the 'family' car) and another when I get moving on the v8 manual swap.
If I can find a cobra irs for less than a mark's irs, is there any reason I should not go for it?
I'm looking to do a lsd swap into my current ls (the 'family' car) and another when I get moving on the v8 manual swap.
02LSE96LSC91SE84TC
Dedicated LVC Member
From what I understand early IRS Cobras are 28 spline and are the same as the MarkVIII diff. Cobras did switch to 31 spline in I believe 03, that you wouldn't want.
If you search the MarkVIII forum you should find some info on them being interchangable.
ILLS
Dedicated LVC Member
The possibility of that happening would be a very rare thing, but like Jason said if you can find one from the 99-01's then it should serve as a decent starting point to build off of.
Sn8kbordin
Well-Known LVC Member
My differential is making noise so I want to upgrade.
What would I need to get any kind of LSD into my LS?
What would I need to get any kind of LSD into my LS?
MMAFIGHTER121
Dedicated LVC Member
so.... what exactly do i need to swap in some shorter gears for better acceleration? just the new gears? or a whole new rear end?
02LSE96LSC91SE84TC
Dedicated LVC Member
Fitting a LSD devise into the stock LS unit hasn't been done but the guts do have similarities to 8.8 units.
Doing what I did is the only way its been done that I know of.
02LSE96LSC91SE84TC
Dedicated LVC Member
3.58 is the tallest gear that came stock in the LS, depending on your year, you may already have it. If you don't it would be cheaper to just get a unit with the 3.58s already in it rather than a build.
If you want more you have to swap in the 8.8 unit as I did.
ILLS
Dedicated LVC Member
Jason when do you plan to go to the track this year?
02LSE96LSC91SE84TC
Dedicated LVC Member
Soon as can.
ILLS
Dedicated LVC Member
I will probably be there with you. I want to see how the cars run this year. I am curious to see how your car reacted to the 4.10's.
02LSE96LSC91SE84TC
Dedicated LVC Member
Hard to say exactly. She really has some quick pull, very different car at the low speeds. I can't imagine not gaining .3-.4 and 2-3mph. Should be high 13 territory, but till its done thats just talk.
I'm very curious to see what you can do. Going to do the LSD first right?
Haven't drivin it in at least a month and probably a month before that.
ILLS
Dedicated LVC Member
I would not be surprised at all if you hit 13's as we had talked about in our previous conversations. We will have to see what it can do.
I do intend to do the LSD first now that I have measured it and things will slide right into the stock carrier. If I had to do the full 8.8" swap with axles and custom brace then I would have probably waited till mid summer before doing that.
The last time I drove the LS was early January when I took care of that slight lean tip in in the somewhat nicer weather we had. Had fun with it for a few hours while logging it and then put it back away for the duration of winter.
02LSE96LSC91SE84TC
Dedicated LVC Member
I guess what will be interesting is if 13.9 will be my "best" run or runs or will I belt that out everytime and see room to sneak a little better time. We will see.
Its hard for me to predict how much better a 60' I will get. A full .1 improvement??
02LSE96LSC91SE84TC
Dedicated LVC Member
Talking about it gave me a itch. So I brushed her off and took a spin.
Chirped 4th getting on a freeway. Thats right 4th!
Chirped 4th getting on a freeway. Thats right 4th!
ILLS
Dedicated LVC Member
Hehehe. That is funny. I too am getting the itch. I have to resist it though due to the nasty salt still being on the roads for a while longer.
02LSE96LSC91SE84TC
Dedicated LVC Member
While the roads are a little dusty here, they are really dry. We missed the last few storms.
MonsterMark
Dedicated LVC Member
Blow Me! More like slipped on the sand/salt changing lanes.
Chirped 4th! Good grief. That tranny must be on its last legs.
I, on the other hand, also took the beast out for a day in the sun today. Just to hear the motor turn over and the thunder bellow from the exhausts made my willie do a wheelie. Unfortunately the racing Goodyears picked up every grain of sand on the road and tossed it with sand-blasting efficiency all over the undercarriage and rockers, thus preventing the climax.
I could have spun every gear had I wanted.
02LSE96LSC91SE84TC
Dedicated LVC Member
Blow Me! More like slipped on the sand/salt changing lanes.
Chirped 4th! Good grief. That tranny must be on its last legs.
I, on the other hand, also took the beast out for a day in the sun today. Just to hear the motor turn over and the thunder bellow from the exhausts made my willie do a tand up wheelie. Unfortunately the racing Goodyears picked up every grain of sand on the road and tossed it with sand-blasting efficiency all over the undercarriage and rockers, thus preventing the climax.
Some of the main streets are surprizingly clean if you stay in the tracks. She chirped, swear. If your not fimiliar when we use the SST mode in our car it shifts way harder than auto even without a tune. With the pressure jacked up it really slams the gears solid in SST.
I have my shift pressure down all 25% too.
I found that when going down the track sometimes I felt more driveline bounce than forward thrust. That and discovering that we have a flex coupler(Guibo) driven 2 piece shaft with center bearing, led me to roll her down. She still is too hard and unfortunately to soft in auto mode. I'm going to get a new tune with the auto slightly higher and the SST mode lowered some. Should be good.
Edit: Remember 4th is our 1to1 gear, its not my overdrive....its not a dinosour you know.
ILLS
Dedicated LVC Member
I smell a race coming on... Family competition hey?
You guys race and I will hold the money................and getaway in my LS.
02LSE96LSC91SE84TC
Dedicated LVC Member
Just about to hit 10k on this modification. All is good definately the best mod to the car. I even think 4:30s would be absolutely fine to run.
TDUB
Dedicated LVC Member
How much are you losing at the top end?
02LSE96LSC91SE84TC
Dedicated LVC Member
You mean did I loss any top speed ability, doubt it. I doubt I've gone much over 100mph in this car. At 100 there is plenty of 4th left, never figured how much though.
chicken
SHEOOOOOOOOT
sounds like you need to wind out 5th and see where she stops