I am in the process of building a block. My engine builder is very exceptional. But with v8s and the like. He is not used to 4 cylinders. I never see anyone with .4 over pistons. Anyone have any input on this? Please no post just saying don't do it because its dumb. Right now its a 2.4 crank with 100 mm rods. Thanks.

 

What block are you running? A 4G63 or 4G64? I personally wouldn't run .40 over bore in either blocks, especially the 4G64 block. The walls just get too thin IMO and then you may have headgasket sealing issues.

There's no such thing as 100mm rods for these cars. If you have a 2.4 crank, you have a 100mm crank and most likely 150mm rods.

-Josh

 

.30 is the most you should go....and even then an 86mm piston is pushing it. Only bore over if you have to.

 

Its on a 4g63 block. I guess that what he said on the phone is 100 mm crank. Bad reception on the phone. The block is already . 20 over. He suggested . 30 over but wasn't sure if they made those or not. I guess I should just stay with .20 over then.

 

Ask your machine shop if you can just get away with just honing the block.

-Josh

 

ask to hone first if not .3 .... .4 is pushing it

 

Has anyone ever heard of anyone using them though. I already ordered them through wiseco, so I think I will have them regardless. Yikes! I under stand that it may cause the hg not to seal so well. I just can't help but think they have to be viable for some reason if wiseco makes them for this specific application. Maybe its uncharted territory. Then again maybe its ignorant. Idk I am not an engineer or mechanic by no means. Is that pretty much the only issue with them, the hg not sealing? Things like this people need to explain to me. Like I'm a 5 year old.

 

I'm running 040 over with no issues. I'm on the stock crank though

 

Awesome! Few questions. Daily driver? Setup? Fuel? Driving habits? How long have you had them?

 

Awesome! Few questions. Daily driver? Fuel? What's your setup? Driving habits? What head gasket did you go with? Thanks.

Phone died sorry for double post

 

About 7k miles so far, I beat the crap out of it(it's my weekend "fun" car) I hit the track 3 times a month with dozens and dozens of street pulls

I'm running 28-30 lbs on e-85
I've got a basic stock turbo+cams Evo, but managed to make almost 430ft/lbs of tq on a mustang with 383hp. Im sure the car would have made 500 ft lbs on a dyno jet and more boost

 

I thought 40 over was a bit much too. I search a lot on here. I think I even made a thread abOut it. Everyone was saying 40 was the most they would go

Wiesco makes .060 over for our cars haha

 

.040'' is too much for a 4g64 but is normal on a 4g63, i have put together 3 motors with 1mm oversize pistons and i never have problems with the head gasket. I used in 2 motors the factory gasket and in the 3rd one i use the cosworth head gasket.

 

I'm on the oem gasket as well

 

I tried searching but could not find that much at all. It seems the only concern is with hg sealing issues. I haven't tried searching yet but wouldn't there be a company that makes an 87 mm gasket? I am thinking I will be well beyond 500 tq, with the black on e85. Just decided to go with it so now I have to pick up stronger rods. I placed my order for these pistons a few weeks back and I was told wiseco wouldn't have them until 28th of May so I am not sure now if I can even change my order.