Tire Size vs MPH Question EVO IX Tranny
 

Quick question for you guys...

I currently have an evo IX with a stock transmission and final drive (5 Speed), I want to be able to run out fourth gear up to about 122mph with out spinning past 7500RPM (stock Valvetrain), if I'm running a 16 Inch wheel what tire size would I need to have to achieve this? Also if I was running a 15 inch wheel what tire size would I need to achieve this?


What I have figured out on my own is that if I'm using a 15 inch wheel I need a 26" tire or a 235/60/15 for a street tire. Which would look ridiculous on an Evo. So Im curious about a 16 inch wheel, or is there a way to run a slightly shorter tire to achieve the MPH goal. Sorry if this has been discussed already I just cant seem to find the info or calculator Im looking for. I just want my car to have the "potential" to run a 10.9 with out having to do valvetrain or changing out to a evo 8 4th gear. I believe the IX has the perfect gearing for the "street" bone stock for anything under 450whp.

And I apologize for my ignorance..

Future Plans would be a STM Willwood Small brake kit with 15 inch drag set up with slicks but I also want to run 16 inch wheels and a street tire giving me roughly the same gear on the street.

From the calculator I'm using, to meet all of your requirements listed above, you'd need a tire that is 27.2" tall at minimum.

I think it's time to start thinking about valvetrain mods.

My stock tranny Evo IX went 11.2@127 revving to 9k. I made over 200 passes on my stock engine with the rev set to 9k. Car only past 7200 in 4th gear at the track. I was on stock wheels and tires.

Stock turbo? :confused:

No lol I wish. It was a SS Auto Chrome 35r that I cost $240 brand new. My first complete turbo kit was a SS Autochrome kit. That kit cost me $900 complete and made nice power.
http://www.ssautochrome.com/level.itml/icOid/1359

OMG it works? How is it!!! Balsy I would never run that setup.

People need to understand that metal is metal no matter how you spin it a 3" exhaust is a 3" exhaust so I wasn't worried about the manifold or down pipe. The turbo was my concern but my friend that does many budget builds uses that same turbo so I knew it was a little laggy but made power. Crazy thing is I sold that turbo to a kid for his S2000 and hey put 54k miles on it before the seal let loose and SS Auto Chrome was willing to replace for free after 3 years of use. I would use the same kit in a heart beat if I had another Evo as budget build project car. My car was on S1 cams and 93oct too back in 2010. Imagine that same set up in S3 cams and E85 that I run now prob a mid 10 car easily.

wait wait wait, you used the SS autochrome knock off full race manifold AND the SS auto downpipe? I was under the impression that downpipe didnt work at all or fit with out removing A/C? Also thats crazy that $250 turbo worked lol. what did you use for an oil feed line for that turbo? I would think the head wouldnt provide enough oil pressure for a joarnal bearing turbo.

If it works hey go for it , I used high end turbo's that blew after 2 weeks, 1 week a few days and they didn't even want to replace them or fix them.

Ugh 9K would put the car around 138MPH, did you have smaller than stock tires? Even 8500 would put the car around 130, based on trap speed that is more like 8350.

on stock valvetrain I ran 8k + for 2 years with no issues in 4th gear at the track with a 6262 26' m&h slicks on 17" wheels also fyi

I was under the impression stock rod bolts dont hold up past 8k rpm, no matter if you have valvetrain done or not

I revved to 9k but im sure going thru the traps I was only at about 8500 or so. In my 8 I rev to 9250 and have seen 148mph (spinning tires thru 3rd) on a 25" tire. Now Im on a true 26" setup and hope to increase my trap speed to 153 or so.