Me and my friend are building an 89 hatch just for fun. I can get 13:1 pretty cheap from a LS, with CTR pistons and a GSR head.

Or just go all out and get 14:1 customs (if possible)

Does anyone have any info on 14:1's in an LS/VTEC, or maybe even straight LS?

How about horsepower advantages over just 1pt in compression.

 

I always like to decide on a valvetrain first and match the compresion. But then again that can be kind of troublesome as well. I say if this is a track car, use as high of compresion as you can with the camshaft/ head package that you have chosen will allow. shoot if this is LS-vtec (Race only) then use 15.1 and some sort of wild single lobe came. i.e toda vtec killers or I think RS machines makes one now too. I guess do it this way. Figure out a budget and then pick what you can that wil best take advantage of the money you have avail .

 

Yea i was unsure on head package etc...i was thinking about somthing extreme like that. Do you have any info on the RS killer cams?

 

how do you run such a high compression without piston to valve contact. i am guessing you would need a wicked dome, and high lift/dur cams to make the most of it?

 

from what i understand with flame travel, the ultra high compression pistons are not huge domed pistons, usually guys will deck the block a ton and mill the **** outta the head. huge domes dont allow for flame travel very well.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ninefivehatch &raquo;</TD></TR><TR><TD CLASS="quote">how do you run such a high compression without piston to valve contact. i am guessing you would need a wicked dome, and high lift/dur cams to make the most of it?</TD></TR></TABLE>

larger valve release!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1 2 NV &raquo;</TD></TR><TR><TD CLASS="quote">from what i understand with flame travel, the ultra high compression pistons are not huge domed pistons, usually guys will deck the block a ton and mill the **** outta the head. huge domes dont allow for flame travel very well. </TD></TR></TABLE>what exactly is decking and how does it deal with compression ...this has always confused the crap out of me

 

decking the block is basicly milling the block insted of the head.

defanatly 14+ if it's going to be a race only car.

 

Heres the new plan... I just have to figure out what alls neccisary to make it work.

15:1 compression LS/VTEC
RS Machines VTEC eliminator cams

I just have to figure out how to set everything up to make it work right. A guy i know in Tallahassee is running this set-up, i dunno how they have the valvetrain set up.

 

think about your cam selection again, why would leslie durst and erick a still be running a vtec cam???

 

i dunno if id go with those cams, but just because he's building a race motor doesnt mean he has to copy erick or leslie

 

Im just gonna look around till i find a set up that works good. Im not even sure i can acheive extreme high compression with out using a deck plate and custom stroker kit.

Thats the info i need to find out, How can i acheive this in an LS/VTEC with a GSR head, And then what kind of cams do i need? Im no expert motor builder so if im gonna have to do a whole lot of cam tuning and all that just to clear then i will prolly go with the VTEC eliminators. Im not even sure wich is best for my application.

Ive been searching for info on this subject but i cant find a whole lot of info.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by evilxkid &raquo;</TD></TR><TR><TD CLASS="quote">decking the block is basicly milling the block insted of the head.

defanatly 14+ if it's going to be a race only car.</TD></TR></TABLE>ight i got it now ...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SIReg9 &raquo;</TD></TR><TR><TD CLASS="quote">Im just gonna look around till i find a set up that works good. Im not even sure i can acheive extreme high compression with out using a deck plate and custom stroker kit.
</TD></TR></TABLE>

if you sleeve your motor with a bigger bore, it well be easer to get higher compresion. the more cc's you have to compress into one space the higher the compression will be.

an 87mm bore ls vtec with a gsr head and totaly flat top pistons will almost yeild 12:1.

 

Yea i understand that concept, but i just dunno if i wanna drop the money on the sleeves.

I know this whole thing isnt gonna be cheap, but we are trying to do this the most affordable way as possible.

 

0 piston to deck height works quite well along with custom made pistons

 

Explain this 0 piston to deck hieght. Is it just milling the block untill they set flush (at 0) ?

 

When dealing with fully built race motors you can make up the piston to deck in either the rods or the pistons... I don't know if anyone mills the block that much.. I guess it may be possible. Just remember this is for full race applications where all aspects of the motor are percisely measured and designed for the application.

 

I wanted to try and Build this myself, But it looks like i may save money and trouble sending this to a Pro.