integra81

i am about to rebuild my 94 ls engine because it has 120k miles on it. I am puting higher compression pistons, titanium vavles and valve springs. I am planing on resleeving it instead of boaring it out to increase displacment Is it possible to put a bigger sleeve in the block instead of boaring out the new one? If so what size? and what sized pistons? im not new to the whole integra thing. True i am olny 17 but i know alot about tegs. I am new to the whole engine rebuild so if you could put your comments in Laymans terms that would help out.

JD_B18CDX

Increasing the displacement of your LS engine will make the engine unbalanced. The crankshaft was created with enough weights to counter vibrations created by the pistons. If an engine is not balanced, it will create a lot of vibrations which will
1. Shorten the life of the bearings.
2. Annoying to drive because the car will be buzzing at higher rpms.
You increase the piston size, then you will also have to increase the mass of the crank weights. A good machine shop should be able to do this.... Expensive tho.
For the money that will be spent, might as well get a type-R or a GSR engine and do external bolt ons.
You are more assured of engine longetivity and reliability.

integra81

i dont have the money to buy a new engine should i just get get new pistons??

JD_B18CDX

If you cannot afford to buy a motor, do not try to modify the internal parts of the engine because it will cost almost the same amount of money as buying a motor.

If you are in a tight budget, just keep the stock parts. If you have the engine taken apart already, just replace the piston rings. It would let the engine retain cyl presures better and its cheap. If you have extra money, check all the other parts for wear, I'm sure you will find more parts that might need replacement. You are not going to get any increase in HP from when your car was new but then you will not have to worry about other problems coming up(like knocking bec. of compression increase) because you were trying to cut corners and not doing the engine rebuild right.
To rebuild and modify an engine correctly requires a lot of money. Most of the time more than just getting a used motor that was build for high output HP like a GSR or Type R motor. And since it was built that way, you know its going to work right.

mannyman

iTrader: (2)

sorry, but i have to disagree with u. He could resleeve the block to 84.5 mm, and the motor will still be fine. The b20b/z is exactly the same as a b18a internally except for the bigger bore, and it has no problems. So i would recomend resleeve to 85mm(golden eagle sleeves), get je pistons, and eagle rods and you should be good to go.
manny

Mikey3000

yeah what are you talking about? you can bore out and put bigger pistons in w/o doing anything to the crank. you can resleeve it w/golden eagle, get je pistons w/je rings, and your choice of rods. i think you can bore it out up to 84.5 mm.

integra81

what would u guys estimate my ls horsepower would be after gettin new pistons and stuff

PhatOptimo

I don't know about the HP# but massive internal work will need to be done to resleve and make it run safely. Its cheaper if you pull the motor yourself. Disassemble it and take it to the machine shop/builder with all the new parts. I am getting my b16 rebuilt right now. I took the block and head to him along with all new pistons, rings, bearings, and he's charging 600. HE is putting the pistons on the rods, honeing the cyls, balance it, polish the crank, arp rod bolts, decking the head and block, hottank head and block, and assembeling it. Thats only the bottom end. Plus I spent over 500 in pistons seal bearings. Anyways If all you want to do is increase compression and a rebuild. You could get my b16 pistons off me (150). Get new bearings and seals maybe rod bolts. Its up to you. Get it done right and you won't be disappointed.

JD_B18CDX

You just proved my point.
$500 for Parts and $600 for machine shop.
Total cost is 1,100. That can buy a used motor already.

I'm not arguing the modifyin an LS engine cannot be done. I'm just saying that it might be worth the money to just buy an engine that is built to produce more HP.

Besides, its not as simple as Get JE pistons, resleeve bolt on and run. You change the bore size and pistons and you are changing
1. Compression ration
2. Cyl volume
which will affect an engines ability to resist knocking. To make the long scientific story short, you are taking (not saying it cannot be done) a risk of rebuilding the motor and then end up spending much more than what you expected. And for what?? 10-20 theoretical HP??
And....
Going back to my earlier point... Although the cranks are the same when it comes to producing the same stroke, the counter weights are not.
WHY?? because a 450cc piston/cyl is lighter than a 500cc piston/cyl. (if you decide to go to a bigger bore). This is another factor that will have to be considered when you do decide to rebuild. To do it right, it will cost you a few hundred bucks to rebalance the crank. As you can see, by this time, your rebuild project is probably a couple of thousands of dollars already.
Again, all of this for what?? 10-20 Theoretical HP against all the other factors that might go wrong if not done right.

A GSR will produce around 170HP (approx 30 more than the stock LS) and will do it consistently because all the internal parts are built that way.

Again, I'm not saying that the LS motor cannot be modified, it would just cost more in the end to do it because aside from the parts and machine shop cost, there will be unexpected expense that will come up from a "DIY" modification.




[Modified by johnd, 7:07 PM 11/29/2001]

PhatOptimo

If you don't have much money don't think about reworing the motor. Get you money together first. I would rather spend 1,100 and get my motor balanced / rebuilt with higer compression than buying a used b16. That just a given for me. Getting an ls built RIGHT will give you much more rewards that buying a type R or gsr. Too many to list. I am staying with standard pistons. I don't know much about changing bore size. I would talk with the guy who is going to build the engine. Theres nothing wrong with changing compression. Knocking can be cured. Its called tuning. If you don't have the money don't try it. HP is not the only thing that makes you quicker. If we took 2 cars with the same hp I could make one quicker with out screwing with the engines internals. Its not all about hp. You also got to put it on the ground! I am sure you know all this. I am staying cheap and reliable with my setup. Thats why I did it. Ready to get it running. Hopefully before x-mas.

mannyman

iTrader: (2)

dude it is as simple as sleeving it and getting some bigger pistons. You see the ls crank is the exact same(meaning even the part # is the same) as the b20b/z block. So he will have no problems with the balance being wack. As for you advising him to get a gsr, yeah he might find one for around 1600. but if he resleeved his 1.8 to a 2.0 with sleeves that can withhold what ever he throws at it and he gets some forged pistons for around 1500 also, what do u think is better???? as for knocking, c'mon ...unless he going to be running some high *** compresion he should be cool. He could run 11.5 compression and his 2.0 will run circles around a gsr.
manny