Hello

2 1/2 months ago I bought an evo 8. After getting it dyno tuned I was out romping on it and busted a piston possibly due to *Edited* Bad Gas. A sample was taken and the octane rating came back around 90.


Anyway I pulled the motor yesterday and dropped it off at the local machine shop which will complete the build. I'm not looking for anything crazy as this is my daily driver. Maybe around 400. Now I have read all the posts about compression ratio and it seems everyone runs e85, but here we don't have e85 - just 93. So I'm going with wiseco pistons and rods. Now to decide what compression ratio would be safest and get me closer to a safe 400whp with the stock turbo.

LAST DYNO AND MOD LIST

Now on the mustang dyno I put down 333hp/365tq with hks 272 cams, hard intecooler piping except I still had the stock licp, full exhaust, 255 pump, larger intercooler and 25psi on the stock turbo


New mods to be added during the build


Larger LICP, 02 housing, crower valve springs, (compression ratio)? , staying with 25 psi on the stock turbo, possibly a 10.5 hotside on the turbo (not sure if the piece of piston i'm missing f'd up the turbine), also getting the head ported and the tb ported. Machine shop for free. Pays to be military sometimes

Thanks all for the responses

 

Anywhere from 8.8:1-10:1 should be fine. You won't notice much of a difference on the dyno, but 10:1 will feel less 'dead' out of boost.

 

If you want to add 70 whp, you'll need to upgrade the stock turbo. Lot's of bolt on options that will easily hit your 400 whp target.

 

You could get there with a HTA71, which is a cheap upgrade from your VIII Turbo.

 

If I stick with the same boost and thats a big if as I have read. 20ish psi is the safest to run on a 10:1 ratio. Heat and high compression on 93 pump gas equals bad juju.


Just want to do this right but safe cause it sucks having to do this. haha


So maybe 400hp down the road, so I will get 10:1 ratio and run lower boost.


Also forgot I'm getting the head ported and the tb ported

 

I would definitely swap out to at least a IX turbo. Especially since you have an 03 EVO...very small and don't like a lot of boost. Stock compression is 8.8:1 so 10:1 should help make a bit more power. If your gonna be running pump and expect to make 400whp on a mustang dyno I'd upgrade to the 71HTA like mdsevo06 said.

 

So I went with Manley pistons and rods with a 9.5:1 comp. The motor is being built as we speak.

 

well ive got an 03 evo as well, my motor took a dump a few years ago. If your buying springs/retainers, makes sense at same time to swap cams, I had hks 272 cams prior to swapping to s2 cams. Big difference in midrange/top end power. Id say if you do that mod, plus like someone said prior swap to a 9 turbo, get it ported. If you can squeeze it in, get a 65mm tb and ported intake manifold/ bigger intake manifold. Itll be close but youll get around your goal of 400, but more like dynojet 400 instead of mustang dyno 400. For that youll need a bigger turbo or better gas or meth.

 

I just got the motor back and I installed it over the weekend. Awaiting trans fluid and a new knock sensor. Will keep updating this thread with install/final HP numbers

 

What started it all





All tore down



Ported head

 

manley is good stuff.. dont make the mistake and reuse the oil cooler or oil pump or oil pickup tube though.. for risk their could be contamination in there & damage.

 

The shop down the road disassembled it and put it back together. I know they reused the stock tube, added a new oil pump, so for the oil cooler should I flush it out?

 

you cant reuse the oil cooler unless you wanna risk spinning a bearing within 100 miles or less.

 

What if I told you the piece of piston missing didn't make it passed the second ring. The machine shop said the cylinder walls were not damaged very easy bore. Nothing touched the cylinder wall

 

Good luck with your build. I also do agree with others about 9 turbo. Just curious, how many milies on your motor? and what size of injectors are you planning to run?