Hello,

I was wondering if anyone knew what the limits of the factory block are? A few months ago my engine suffered catastrophic failure and as a result it is looking like I am going to have to go to .060 over (86.5 mm). Is this safe?

My long term power goals are less than 500 awhp, but I want to build something that will last as well.

The machine shop is going to punch the worst hole to .057 and let me know but I wanted to see what the facts are before making a decision.

Thanks,

Vincent

 

I highly suggest against it... I believe its been done... But if you are gonna go that route get a lower milage 4g64 block have the same pistons but higher displacement and not worry in the long run if the motor is gonna come apart and cost your 3k plus...

 

I have a few dsm buddies who are .80 over with 450+

Up to you.

I would definitely do a 2.0 long rod which may help with side loading over a 2.3 or regular 2.0

 

I had 87mm pistons for a long time with no issues. Made 425 on a mustong dyno FP black. It only blew up from a timing issue that was tuning related. With 86.5, you should be fine if youre running less then 500whp.

 

The issue with running a 4g64 block is you have to buy an adjustable cam gear and a MiVEC oil feed line, and money is already gonna be tight (everything was destroyed).

I am planning on buying rods too, but after talking with English racing, I was told that a long rod setup has basically no performance advantage and that I didn't need to go that route with the stock crank.

Any other input would be greatly appreciated.

Thanks!

 

Ok, I have another question. Can I use an older 7 bolt block? If so, how would the feed line for the MIVEC system work?

 

A quick search says no...

 

I just made a customer mivec line for my car... A 14x1.25 to -6an adapter... 90* -6an fitting 45* -6an fitting and hose... Oh and saidly a -6an honda fuel banjo fitting... You just need to keep the block banjo bolt because it has a check valve...

As for the cam gear you can modify the stock mivec gear using aarons how to to soak up the adjustment... So back to using the 2.4 block...

 

Do you have a link to this?

 

I think I am going to trust my machine shop and go with the .060 pistons. I find it hard to believe that .020 is going to be the difference between being able to run 8 or 900 horsepower and 450...

 

I would never go more that .20 over just my opinion

 

If the other 3 bores will go .50mm/.020 have the machine shop sleeve the bad bore and go to the .50mm/.020

It may cost about $100 for the sleeve and labor to install it. Plus that will leave more for the next build.

 

Well good news! The machine shop made a mistake and in reality a .020 bore is all I need! Woohoo!

 

SCORE! Good deal!