Will be doing my ls swap soon and was just wondering why i don't see the ford 9" rear end being used? Thanks for any info.

 

Almost everyone likes to keep the IRS, which means a 7.5 or 8.8 from a mid 90's Tbird/Cougar or the Getrag from late model GM products. You can have a 9" made into an IRS but is it really worth it? Miatas tend to be traction limited because you just can't get enough rubber on the road.

Mike

 

I had planned on taking mine to the drap strip a few times a year, and also hitting the ice drags in winter with it. Was just thinking a narrowed 9 " and tubbing it out may be more suited for me for strength and allow me to get that rubber under the car, if i go that route it would be straight axle, not made into IRS. Would the 7.5 or 8.8 be able to take the hit with drag slicks, I don't know, anyone done that with out breaking it? Thanks.

 

The problem with the 7.5, 8.8 or even the GM rear on the drag strip is not their respective strengths but rather the inherent wheel hop issues experienced with a IRS. There have been several converted cars built specifically for the drag strip and most of them have had exactly what you're suggesting in the rear. A live axle seriously takes away from the handling of the car, but if you're building it to drive in a straight line that's not an issue...just be careful about talking about your plans over at M.net, they'll burn you at the stake for blasphemy.

Please keep us updated on your progress,

-Jason McCully

 

Thanks for the info. I have had the car for for 10 or more years and it still only has around 32 k on it. Probably wont start "doing" anything until spring, were trying to move, but will gladly keep everyone posted once we get into our new place. Been at M.net in the past, won't go back, this site is a huge help, keep up the good work. thanks to all, I am sure I will have more questions, Scott. "ins2g8r"