ok........ i got a ls block and im buildin the whole thing for my 95 gsr...... but are the gsr and ls rods the same???? like, can i use the ls crank, my stock gsr rods, and then high comp pistons???? and if i do that do i need to buy pistons for a ls or for a gsr. i want to go 12:1 at least, 12.5 or 13:1 if i can find them. then im gettin everything balanced and blueprinted blah blah blah...... and which ecu should i use,the ls ecu and get that tuned and add like a vtec controller since it aint got a knock sensor or should i use the gsr ecu? aaaand what all parts need to be carried over from my car over to that block? i've built a motor for my crx before, but this is confusing me a little bit. any help is appreciated. or if anybody just knows a good site about ls/vtec that would help a lot too. thanks.

 

first of all b16 pistons will fit on ls rods with no problem but b18 pistons have to have the rods milled down some. u will need to use the ls rods, for your ls vtec. i have ls rods on b16 pistons with a b16 head and i have about 12:1 compression, but if u using a gsr head yours will be higher cause i gsr head give a higher compression than a b16 head.

 

You are making it too complicated. Just get some LS Eagle rods and some high compression JE pistons.

BTW, P28 seems to be the ecu norm...including for myself.

Here is a basic lsvtec writeup...http://www.c-speedracing.com/howto/lsvtec/lsvtec.php

 

LS and GSR con rods are not the same. If you plan to use oem LS or B20 rods at least have the oem rod bolts replaced with ARP bolts.
If you want high cr like you are suggesting and are not going to use oem piston offerings.....you are pretty much forced to buy aftermarket forged pistons. If that is the case you should just save up some extra dough and buy aftermarket rods as well. Eagle rods would be a good economical choice. Using aftermarket pistons with oem rods will have pressed pin/floating pin conflicts.
A p28 ecu would be a good choice over the GSR due to the lack of secondary intake valve controls and knock sensor; assuming you will be using a B16 or ITR intake manifold. The p28 ecu has to either be chipped with a new program or Hondata/AEM/etc equipped to run that engine. An LS ecu with a Vtec controller is not a good choice.
Hope that helps some

My only question is why not keep the GSR block and increase the displacement instead of going through the whole LSVT ordeal? Simply sleeving your block to 84mm and replacing the pistons/rods would do the same job. Plus you would be keeping the main girdle and rod ratio for higher revs. Just a thought.


[Modified by SLPR, 5:36 AM 1/7/2003]

 

You can't use gsr rods on an LS/B20 crank because they are narrower on the big end than the LS rods. If your using the gsr intake mani use the gsr ecu(you'll want the dual runner control for daily driving). Otherwise a chipped P28(or hondata) is the best option. You will need lsvtec dowel pins(fullrace.com) or have the head machined to accept ls dowels. Keep in mind that the LS dowels are on the intake side, and the gsr dowels are on the exhaust side.
The oil drain back passages are slightly misaligned, so use of hondabond on the oil return passages (top and bottom of head gasket) is recommended.

SLPR makes a good point on sleeving your gsr block.

 

hmmm so.... if i use my intake manifold, use a gsr ecu.... and like 12:1 b16 pistons and ls eagle rods will do fine right??????? and if i buy a type r intake, use a p28.... lol just to make sure im understandin this

 

Yep those would work