Bore Size?

Johnybeas · #1 10-13-2010, 02:54 AM

I saw that Marisa did a 98mm bore on her build I was just curious what everyone else has done so far. Cometic makes an EG33 head gasket in 98 100 and 102. just trying to get a consensus of what people have done.

Cam · #2 10-13-2010, 02:56 AM

Mine were slightly bored to give the proper skirt clearance for my ecutune pistons. Not even to 98. They are 11:1

Crazy_pilot · #3 10-13-2010, 08:03 AM

I believe stock are 96.9 and the ECUTune pistons are 97, which is really just an aggressive honing. The EG33 RS that RallyBob built has a 100mm bore.

Cam · #4 10-13-2010, 12:56 PM

It depends on the piston, I went over 97. But IIRC, the 11:1 pistons had to be enlarged to get the compression.

oab_au · #5 10-13-2010, 04:41 PM

Quote:

Originally Posted by Cam

It depends on the piston, I went over 97. But IIRC, the 11:1 pistons had to be enlarged to get the compression.

"Enlarged to get the compression"???????

Harvey.

Cam · #6 10-13-2010, 06:07 PM

You would have to ask LAN. I can't remember why exactly they were enlarged diameter wise. But i thibk it was somewhere along those lines

Crazy_pilot · #7 10-13-2010, 07:14 PM

LAN lists the bore of the 11:1 pistons as 97.4mm.

Cam · #8 10-13-2010, 07:32 PM

I did not know if that was common knowledge or not and I did not qant to reveal any technical data if it was not mine to share. My cylinders were indeed bored to 97.4 mm

TomsSVX · #9 10-13-2010, 07:33 PM

enlarged so that all holes would have to be slightly larger... Don't want to get a hole you need to be slightly smaller now would we?

Tom

Cam · #10 10-13-2010, 07:37 PM

Speculation but he may have slightly increased diameter to compensate for the radius of the dome. In other words maybe he felt if the dome was too radical it would have a negative effect on the burn.

Johnybeas · #11 10-14-2010, 02:47 AM

Tom what size did you go on your Silver?? did you do the CP 8.5's??

TomsSVX · #12 10-14-2010, 05:10 AM

Quote:

Originally Posted by Johnybeas

Tom what size did you go on your Silver?? did you do the CP 8.5's??

It wasn't a set size... It was honed per the piston like 4 years ago

Tom

icingdeath88 · #13 06-30-2011, 01:38 PM

I would like to bump this thread and ask again, how big of a bore can we go on the stock block? I am getting ready to order a set of pistons soon.

Crazy_pilot · #14 06-30-2011, 02:48 PM

100mm has been done and worked well, 102 is probably fine as well. Anything more and you won't be able to find head gaskets easily. What are your build plans?

icingdeath88 · #15 06-30-2011, 02:57 PM

As of now, I've only just started tear-down. Basically, I have 2 spare motors, and the motor currently in my 6-speed car is not quite right. It'll last quite a while as-is, I expect, so I think the smart thing would be to rebuild a motor in the meantime. I have the luxury of a build without down-time for the car, so I think I should take advantage of it, and I'm certainly not going to rebuild it without improving upon it. I'd like to go turbo. I have the ECUtune stage 2, MAF, and injectors already. I'd like to get about up to the max that that setup can provide, so I don't have to go standalone (although I wouldn't be opposed to doing so later).

Who did 100mm? Did anything else have to be done? Stock sleeves and all?