Anyone have an comments or experience in boosting on a GEM sleeved b18b block w/ an 86mm bore? I know it starts to get real thin between cylinders so you guys think I'll just keep blowin headgaskets?

Thanks

 

I want to say no, since I don't know anyone running that big of a bore and boost.

Is it Oringed or step decked? I'm assuming probably not.

 

I don't think you will have enough surface between the bores for a gasket to hold, Plus the bores would be very thin.

 

Neither O-ringed or step decked... Should I send it back to GEM and get it o-ringed to help out a little?

 

thats real thin...maybe you can sell it? trade it? i dunno if you can oring it either..call up ge and see what they say

 

i think you can run arond 5-7 pounds on the 86mm bore but its still thin. Should make some crzy torque with that setup.

 

even 85mm is pushing it. works well, but would still make me nervous. 86mm??? i wouldn't try it.

 

Use ALOT of copper spray... Just kidding.

I'd probably go all-motor with that block.. How about you sell it to me? And ill give you my b18c1 as a core return? lol

 

I planned on boosting at 85mm but I dropped 2 valves (REV stainless steel) the other day and scratched up the sleeves...it isn't real deep and I think I can get away with 85.5mm but I'm not sure yet..

Here's some pics..

Anybody want a custom made JE Piston? :doh:

..and for the best part...


Now whats gets me is what caused this..
I was accelerating w/ approx 60% throttle and at about 30mph in second gear that happened...I didn't jump timing, I wasn't detonating...

I did put 100shot on it for 7-8 runs with 100octane (9:1 C/R) and only detonated once but that was 2 weeks before this..

I think the valves just got weak after a few thousand miles cause where the rocker arm meets the tip of the valve, they looked crushed and I adjusted the valves every oil change.. I'll get some pics of that later..


[Modified by Vadian, 7:09 PM 1/29/2003]

 

I had an 86mm bore gsr block for a while and I would not suggest boosting it. It is also impossible to oring that big a bore. there is not enough room between the cylinders to even fit two thicknesses of the wire. Plus GEM told me they cant oring it.

 

hey highbrid: you only ran a 13.3 on slicks with 310whp in a HB

 

i looked at the profile and that time looked to be on motor.

as for 86mm bore, with a cast iron sleeve. i say go for it and let us know how it works.

 

Yeah, I'm give it a try.. hopefully I can go 85.5 but if 86, then so be it. Besides, as long as its tuned well, whats the worst that could happen besides blowing headgaskets?

I'm lookin for someone who has already done it.
Is there anyone or do I get the honor of being the first?

 

i ran 13.3 with slicks on my stock internal crvtec, all motor. I have 310hp in my new motor that i have not ran yet.