I got a built bottom end b18a ls block. Brand new jdm p30 pistons, new rings, new bearings, block has been hot tanked and honed. With a Ls head and OEM headgasket I will be running about 11.59:1 compression. If I add a SI head and do LS/Vtec I will get 12.18:1 compression and with a GSR head I will get 12.49:1 compression. These are good starting points for a good N/A setup and if I add a nice cam/spring/retainers I can have a good quick daily driver. Some people are against boost on a high compression motor and some live by it. I know I won't be able to run high psi and a smaller turbo will probably work better then a larger one for me. My goal is somewhere around 250-300whp because this is a daily driver. Or would it be better to go with a Jackson Racing Super Charger because there is less strain on the motor? Just asking for ideas. I know that a good tune is needed to stay away from detonation. I have researched a lot just wanting to hear from others on here. Thanks. Will be running a gsr tranny also so I have a little bit longer gears than a SI tranny.

 

i say boost it with a 2mm head gasket, it will drop your compression back down to 11.5:1, high compression + big turbo = no lag

both put strain on the motor and ive seen both blow motors, i just rather not go with the supercharge cause top end sucks with them things.

 

what do you think I can safetly push the motor to, with good injectors and a nice tune?

 

250-300whp should be attainable, so long as you or your tuner isn't afraid to push the engine a bit. timing can be quite intimidating on a high compression engine.

 

I wouldn't go high compression + boost on stock internals.

I've seen and have experienced stock internals failing from boost. Ring lands aren't bullet-proof.

 

ring-lands break because of the tune, not the power.

 

I didn't see your post above mine. You basically were getting at the same point as me.

IMO I wouldn't do it.

 

the motor is built and put together, so I'm like you I question boosting on high compression. Think I might either run it N/A for awhile and then buy forged rods, and pistons and then install them. Or I might get the turbo setup now and run low boost at like 5psi for awhile. Had a friend run a stock b18c5 with 5psi on a t3/t4 .63 all day long with no problems.

 

The late, great Brian Arbogast pushed 655whp/426wtq with a stock type r motor... i'm not sure what his timing was like but it was a hefty pt 70 turbo. But then again he was probably one of if not the best tuner in NOVA.

 

Put some cams in a head and get tuned.