The last few days i've decided to og from 13:1, to 14:1, and now i've decided to go 15:1!

I know im gonna have to have the VTEC eliminator cams, and custom pistons. But race engineering says im gonna have to have a custom stroker kit.

Im gonna be using a B20 with a GSR head. Its strictly drag only car.

So what all will i need to make this work?

 

89 stroke 86 bore
9cc piston
0 deck block
gsr head
15-1

keep it vtec

 

So basicly im foreced to sleeve the block if i want this compression? What would i end up with if i used 84.5mm's

You seem to know about all this, what type of cams would be best suited for this? regular VTEC cams or VTEC eliminators?

 

you don't need VTEC elim cams to make good power. There are several members on this board that are using the reg RS machine cams on the street and on full race 15.5:1 compression setups.
the RS cams are amazing. will make great power with a basic ls/vtec setup as well as full out 15:1 compression race motor.

 

I wouldn't go 15 to1 on a stock sleeve block. You could get 15 to 1 with a welded head. There's a hand full of good vtec cams I like jun3/skunk2.

 

Ive also been wondering about the welded head's? whats the benifits. and pupose of this?

 

smaller chamber more compression

 

Wont like the extreme heat from welding in the combustion chamber change the internal properties of the casted aluminum and have a high chance of it cracking?

-Eric

 

Yea i dunno about all that, C-speed racing says i can make 14:1 with an LS block, CTRS, GSR head, and 0.0 deck to piston height and a 2 lyare head gasket, wether that would work or not i dunno, but i was lookin at that cus of the price factor, and maybe some EF-1 cams to match it up with

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SIReg9 &raquo;</TD></TR><TR><TD CLASS="quote">Yea i dunno about all that, C-speed racing says i can make 14:1 with an LS block, CTRS, GSR head, and 0.0 deck to piston height and a 2 lyare head gasket, wether that would work or not i dunno, but i was lookin at that cus of the price factor, and maybe some EF-1 cams to match it up with</TD></TR></TABLE>talk to rocket ...me mite be able to make you some sick cams for a 15:1 compression motor

 

He recomended the M24e's i believe they were?

 

Our old 85mm 15.0:1 LSVTEC race motor (PR3 cylinder head too) from a couple years ago didn't have VTEC killers or anything special we just ran JUN Killers and SK2ST3 cams. Both worked okay and the motor made 265whp on our M.D. (nothing special but okay for the time). Scott's running M24E's in his 13.20:1 street motor which is what Robert recommended so I'm sure you could get away with M25's or more but who knows... Just my $0.02

 

I really wanna stay away from sleeving a block. I know its gonna be hard to make that high of compression without doing it though. Maybe 84mm B20 could hold it. I just need to figure out how to do the match for myself and see what will work.

Im lookin for the best, cheapest set up, Heres what i figure now, I found an LS short block for $125, CTR pistons for 250$, GSR head for 400$, thats real cheap, and theres alot of potential there.

I know its alot more money involved, but you compare 125$ to 800$ or so for a b20, And 250$ for CTR's compared to 550$ for CP's

Im just trying to make somethin happen for as little as cash as possible

 

I know you want the displacement but even running 15.0:1 on a stock sleeved B20 is going to be pushing it. If I was trying to do the same as you I would probably "try" to attain that compression with a B18C, with the linked iron B20 sleeves if you get a crack you're screwed. We've never done anymore than 12.5:1 on stock B20 sleeves so I don't know what to tell ya. Just don't be too disappointed when a sleeve cracks with 15.0:1... Any route you take, Good Luck

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SIReg9 &raquo;</TD></TR><TR><TD CLASS="quote">He recomended the M24e's i believe they were? </TD></TR></TABLE>im goin to be running them on my 13.5+:1 85mm Ls/vtec ...i remember i think it was a thread i posted a while back rocket said the m25's and m25e's will work with 15.+ compression motor ...but rocket knows best ...i mean he did make the cams lol ...

 

On my turbo ITR motor(wich i never ran)

I had a an LS crank and LS rods in there and they worked no problem.

I wonder if i was to use a GSR, with LS crank, rods, and CTR pistons, how would that turn out? seems to be a fun thought

 

Yea, that's pretty common and will help bump your compression up a hair more than with a B18C crank. Depending on what cylinder head you'd be somewhere ~13.1:1 (PR3) to ~13.5:1 (P72) with OS PCT slugs.

 

What if i went with custom pistons in a GSR with the LS Canks and Rods? whats the highest, usable compression i could use? or acheive?

 

There are a lot of variables, just remember that your stroke is going to be maxed (atleast if you're using a factory crank) so the only way to get your compression up higher to have custom pistons made with more dome, change cylinder head (from PR3 to P72 will yield a slight increase), headgasket (which I personally will not do), or displace more via bore.

 

Im just gonna throw together an LS/vtec with a GSR head and PCT's, and mae it with the 0.0 deck to piston height and hope it works