Miata

[B00stLek]

What kind of hp can shock rear end hold I'm looking for about 300 to 350

[metalman]

What year Miata?
Early model, 90-93 diffs, can't take alot/much of abuse at all.
94 up Torsen type diffs can take a good bit but 300hp high RPM clutch dumps will undoubtedly take a toll...as well as possibly implode the tranny.
If you seriously want a beast to hammer on then a typical approach is to utilize some drivetrain parts from a turbo Rx7...and even that has it limits.
Of course driving style and use are major factors here.

[Cool Cat GTR]

What kind of hp can shock rear end hold I'm looking for about 300 to 350

I will be curious to see how you manage to get that kind of horsepower out of the engine and for what reason. I have 200 rwhp on mine and no problems whatsoever. I road race/autocross the car on slicks and still have more power than I need. I can light up my rear tires anytime I want so grip becomes the issue. Miatas have unlimited aftermarket support. Rspeed has some great advice on diffs and your call to them would be well worth your time. Be sure to concentrate on bushings, motor mounts, and chassis reinforcement too else you will twist the little car to pieces. The tranny takes a beating even at 200 rwhp. For some reason, shifting to third after running second out is a problem on every high powered Miata I have ever seen. Just my two cents. Let me know if I can help you.

[Doppelgänger]

300-350 is ok on 94+ Miatas with LSDs. The big enemy is wheelhop. I have had my 4:10 torsen from my 96 put in my 99 and its got about 250k on it with no problems *knocks on wood*. But then again, i am only at about 200hp also. There are a few guys on miata.net who are running these numbers... you should go on there and ask also.

[Cool Cat Racing]

The problem with the diff isn't its power handling capabilities, its how well at that power level can it disperse it. The stock diff has issues sending power to each wheel as its supposed to at that load. If you can find one use a GURU ATB LSD or a KAAZ clutch type and this will not be a problem. Drag racing this type of car is not a good idea, as mike pointed out wheel hop is a major problem. That kind of power in nearly any form of real world racing is pointless because the chassis simply doesn't handle it well.

[kfzemx3]

I will be curious to see how you manage to get that kind of horsepower out of the engine and for what reason.

Not sure what motor he is using, but if it is the 1.8 bp there have been protege guys and a few other mx-3 guys who have hit 400whp on stock internals, now granted the motors didnt last to long with that much power on stock internals. But just looking at the motor you should be able to obtain 300-350 with a decent turbo setup and using megasquirt/haltech/tech3. Many guys have done it in the past. Infact there are guys with the 1.6l b6t out of the old 323gtx that are making fairly close to 300whp.

As for if the diff will handle it, dunno might want to go the rx7 rear diff route, or even use the rear diff off the awd 323 if you can find one.

[Cool Cat GTR]

Check in the Nissan Forum. It looks like a SR20DET might be the engine of choice for the thread originator.

[DRFTR]

i'm doing a sr20det swap in a miata...should be a lot of fun in that car...only mods i'm doing to it after the swap for now is of course intake, 3" dp and exhaust, boost controller and safc