need opinions- which bottom end?

We may earn a small commission from affiliate links and paid advertisements. Terms

stmotorsports

Senior Member
well here's the deal- I'm currently rocking a 2000 Civic Si with a street JRSC kit (~6psi) on the stock B16A2. The problem is that the car has absolute dogshit for power right off the line until it starts building boost. There was already a 7.5lb flywheel and ITR cams in the car when I got it which I know aren't helping the matter, but I know going back to stock B16 stuff won't help much either. Looking for more off the line oomph plus more power overall would only be a plus.

So basically I'm wondering if I should go with a GSR, LS or B20 bottom end. I know the GSR would pretty much bolt right up, would have the oil squirters, would be around ~9.8:1 comp with the B16 head, and would probably have decent off the line jump with the stock flywheel/etc. But I also know I'd get even more tq out of one of the other 2 choices, although that would involve running the external vtec lines and I'm not sure what else.

Just for reference- the car is mostly used for autox, some track days and daily street driving.

thoughts?
 
hmm hadn't considered the bore unshrouding the valves, with the larger bore I could probably do some chamber work and blend the valve area to further unshroud them too

as far as tq/low end power is concerned, how much of a difference would there be going from the B16 w/ the ITR cams and 7.5# flywheel to a GSR bottom end with either GSR or ITR cams and stock flywheel? Only reason I'm wondering is because I might know someone local looking to dump off a GSR bottom end cheap
 
I was orginally planning on going B20 but dunno tho- I've heard so many horror stories about stock B20 blocks not getting along with boost
 
Well, figure that there's an 18ft.lbs. difference between a stock B16A2 and B18C1. So, maybe around 23-25ft.lbs. with the mods. The B20 will net more even if you don't touch the head.

you mean 12ft.lbs..

**edit.. nevermind.. i see a a2 only has 111.. mine has 116
 
Ya I think that they got the 84mm bore by using thinner sleeves in the same block. Essentially they bored it out to 84mm... Someone correct me if I'm wrong.
 
Back
Top