hebijake

yea the two block's are different deck heights. I "think" I may have also heard that the mains are different sizes so it's hard to put the GSR crank in a LS, but then again just recently I heard of someone who used it in their ls/vtec making big power so?? but it is definately true that the ls rods are wider thickness... if you put a GSR rod on a LS crank journal, you'll see that there is a TON of side to side play. enough to kick a rod and kill your oil psi'g. I know because a company sent me forged GSR's before and when I bolted em on we were like..... WTF!!??

mugenblacky16

I got some LS rods and pistons and a LS crank from a buddy for free. I have a set of B16 P30 (6.93cc/cylinder) pistons. My goal is to put the p30 pistons on the LS rods and mount them on the LS crank inside the GSR block. The thickness of the LS rods don't matter sense they're going on a LS crank. The wrist pins are different sizes, but the machine shop can handle that for under $20. Is there any problem milling down the GSR desk .55mm other then the cam timing being off If the desks are different heights, then why do the B18a/b/c/c5 all have the same piston-to-desk height I also need to find out if the mains are the same size. If all goes well I should be able to get between 12.13-12.88:1 cr depending on if the desk needs to be milled or not (w/ 0.02in headgasket). Thanks for all the info so far and keep it coming. Let me know if anyone thinks this won't work and for what reason. Thanks.

Racintweek

non-PCT b16 pistons can be pressed on to LS rods without any mods, if an LS and GSR use diff t-belts in theory if you milled the GSR block to match an LS deck hieght you could use an LS belt and be fine.



piston to deck and deck hieght are totally seperate measurements though deck height can affect piston to deck height. piston to deck is how far in or out of the bore that the piston sits at TDC. deck hieght is how tall the block is

Tom-Guy

Which timing belt depends on which water pump. Deck height is piddly ---- when the belt adjuster swings so far back and forth.

mugenblacky16

I disagree. If I mill .55mm off the block its going to effect my timing quite abit. I tensioner might swing enough to take the slack out, but it on the wrong side to compensate for desk height. The belt has a straight shot from the exhaust cam to the crank gear. If that distance is shorter then no tensioner puller can fix it. It doesn't even come into play. I guess you can get lucky if the amount you mill is the same as one tooth on the belt. That would line everything up nice, but one tooth is alot.

Tom-Guy

I said nothing about timing. I said which timing belt to run. If you read my post in context you'd understand what I said.

Slo_crx1

And to do one of these properly you should stick with the gsr/b16 pump...the LS's tend to cavitate at higher rpm's, although you still shouldn't rev a b18a1 bottom setup past the 8100 mark.

Which brings up another point to this thread...why swap in a lower rod to stroke ratio setup? You'd only be increasing the lateral loading on the cylinder walls. Effectively there is no gain, except for a slightly lower torque curve.

Tom-Guy

Lateral load in a small bore engine with lightweight internals is a lie. 1.54:1 vs 1.52:1 ratios being a significant difference is... uh...

Is your problem about revs with the fact it's a B18A1, or an LS? I know the B18A1 have the crappiest sleeves of all the 1.8 blocks, I'm pretty sure it's not the sleeve itself but an inferior way of pouring the block around the sleeve. I see a lot of them with big chips out of the aluminum at the top of the sleeve perimeter.

Slo_crx1

R/S ratio is pretty close on either ones. But you do have to agree that it's better to have a r/s ratio that's higher than lower. I was pretty much taking it on the basis that he planned on just swapping over crank and rods, and slapping his b16 pistons on and...voila, 8500rpm like every other ls/vtec idiot out there. As far as the lateral loading goes at those rpms, I have seen quite a few (at least 5 by one individual who refuses to change his ls/vtec setup :P) where the bore of the block tends to distort over time, eventually egging the cylinder or causing excessive wear to the sleeve. And seeing that larger displacement really isn't a viable option (you can only take a honda 1.8 so far), pretty much all you're left with is rpm to try and create more power. Granted, he's not trying to build a motor comparable to a honda f1 motor (gotta love their 2:1 r/s ratio ). More or less I was just pointing out a very commonly overlooked aspect in n/a builds.