IGotVTECyo

Basically im trying to find out which is better for turbo a 81.5mm Gsr, or a 81.5mm LSvtec? Im sending off my motor in about a little over a month, an im just going to get the motor bored out to 81.5mm an im not sure if i should just leave it gsr or throw in ls crank. So basically is there like a huge difference between the two as in spool times when your turbo, or power period. I mean i already know a lsvtec will make more torque flat out period an i know a good bit about the swap. But does it make a huge difference compared to a gsr if both were 81.5mm? The turbo that is going to be on the setup is a sc61 by the way if anyone cared to know.

Finland

Honda motors were made to spin...go with the GSR crank

drumking15

i personally love the added low end torque...and extra displacement never hurts...i love my boosted ls/vtec w/ my hx35 turbo...somewhat very similar to the sc61...mine is bored out to 81.5 also w/ about 6k on it so far...rips like a bat outa hell! only spinning it to 8k tho...keep things under control

mike1114

iTrader: (1)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by drumking15 &raquo;</TD></TR><TR><TD CLASS="quote">i personally love the added low end torque...and extra displacement never hurts...i love my boosted ls/vtec w/ my hx35 turbo...somewhat very similar to the sc61...mine is bored out to 81.5 also w/ about 6k on it so far...rips like a bat outa hell! only spinning it to 8k tho...keep things under control</TD></TR></TABLE>

cept my turbo is a t3/t4 57 trim!!
to the LS crank!!

sloweredcivic

i guess i don't under stand is this a gsr block you want to put an ls crank into? or are you just useing a ls bottom end instead of a gsr bottom end. what kind of power differences foes this make?

drumking15

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sloweredcivic &raquo;</TD></TR><TR><TD CLASS="quote">i guess i don't under stand is this a gsr block you want to put an ls crank into? or are you just useing a ls bottom end instead of a gsr bottom end. what kind of power differences foes this make?</TD></TR></TABLE>

you can do either...only benefit is stickin w/ the gsr block you have an oem girdle...w/ the ls you wouldnt

its not power...but more or less low end torque...just compare some ls/vtec to gsrs and youll see the slight increase in torque

Dunc

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by drumking15 &raquo;</TD></TR><TR><TD CLASS="quote">

you can do either...only benefit is stickin w/ the gsr block you have an oem girdle...w/ the ls you wouldnt

its not power...but more or less low end torque...just compare some ls/vtec to gsrs and youll see the slight increase in torque</TD></TR></TABLE>

^^^x2 ls/vtec all the way in my mind. Also if you're engine is apart and everything, you could just go with the ERL 5-main girdle which will then far out-shine the GSR OEM girdle.

mike1114

iTrader: (1)

GSR also has internal oil line for vtec, where LS block needs an external oil line to the head.

saver

ive always wanted to ask this question but i didnt know how to say it. well from wat i have learned is that with the r/s ratio on the full gsr block would be more reliable then the ls/vtec. for me i rather go wit the one thats more reliable and also quick. but then again i would do both so im stuck also.

boosted92

The LS crank is barely any longer of a throw than a GSR crank. These huge torque gains you guys are thinking of are 99% in your head, because it really doesn't make that huge of a difference. On a 300 WHP setup you're looking at realisticly about 5 ft-lbs of torque, maybe 10 tops.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by saver &raquo;</TD></TR><TR><TD CLASS="quote">ive always wanted to ask this question but i didnt know how to say it. well from wat i have learned is that with the r/s ratio on the full gsr block would be more reliable then the ls/vtec. for me i rather go wit the one thats more reliable and also quick. but then again i would do both so im stuck also. </TD></TR></TABLE>

If by "what you have learned" you mean "the banter you've heard on the internet", then yes, the LS has a "worse" rod/stroke ratio at 1.54:1 vs. 1.58:1 for the GSR. You really should learn about how the rod/stroke ratio of a motor impacts it's reliability and longevity. That is a tiny difference, and the R/S ratio of the LS motor is not going to impact how long your motor lasts significantly. Same goes for thinking the added stroke of the LS crank is going to effect how high your motor will rev, both cranks with the proper turbo, cylinder head, and camshafts will make power to 10000+ RPM's, and at that point I'm much more concerned with the terrible inaccuracies of a distributor setup rather than my motor having an extra tenth of an inch of stroke.

saver

good way of putting it.