Increasing R/S for Ls/vtec
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Increasing R/S for Ls/vtec
The main reason why ls/vtec isn't that great is because the block has a 1.54:1 R/S ratio...
Rod length: 137mm
Stroke: 89mm
137/89 = 1.54
Now, how in god's green earth can that number be made higher? De stroking it would totaly take away from the idea of ls/vtec (at that point it would be cheaper/less time and labor consuming to get GSR motor). So, i guess increasing the rod length, but wouldn't that make for a large increase in compression?
im stuck... someone give me a good rod length that will yield a not so deadly compression ratio (less than 12:1) or just something that can be run on 91 octane.
Ryan
Rod length: 137mm
Stroke: 89mm
137/89 = 1.54
Now, how in god's green earth can that number be made higher? De stroking it would totaly take away from the idea of ls/vtec (at that point it would be cheaper/less time and labor consuming to get GSR motor). So, i guess increasing the rod length, but wouldn't that make for a large increase in compression?
im stuck... someone give me a good rod length that will yield a not so deadly compression ratio (less than 12:1) or just something that can be run on 91 octane.
Ryan
I
Joined: Jan 2001
Posts: 56,525
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From: Westside til I die
That is not the main reason that lsvtec isn't great. The GSR and Type R have a r/s ratio of only 1.58, not much difference compared to the LS. That is not the issue with LS vtec. The problem is that most people think all that is involved is bolting on the vtec head, and the LS block can automatically take their newly added 1000 rpms from the vtec ecu. If you want to make it a safe revver, you need arp rod studs, and use a crank girdle.
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Team B.O.B.® - Ballaz on a Budget
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Originally posted by dubster99
That is not the main reason that lsvtec isn't great. The GSR and Type R have a r/s ratio of only 1.58, not much difference compared to the LS. That is not the issue with LS vtec. The problem is that most people think all that is involved is bolting on the vtec head, and the LS block can automatically take their newly added 1000 rpms from the vtec ecu. If you want to make it a safe revver, you need arp rod studs, and use a crank girdle.
That is not the main reason that lsvtec isn't great. The GSR and Type R have a r/s ratio of only 1.58, not much difference compared to the LS. That is not the issue with LS vtec. The problem is that most people think all that is involved is bolting on the vtec head, and the LS block can automatically take their newly added 1000 rpms from the vtec ecu. If you want to make it a safe revver, you need arp rod studs, and use a crank girdle.
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Joined: Dec 2000
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From: Madison, WI
http://www.z10eng.com/products.cfm#bg
That, ARP rod bolts and fresh bearings will make the bottom end plenty reliable.
That, ARP rod bolts and fresh bearings will make the bottom end plenty reliable.
Wannabe yuppie
Joined: Dec 2000
Posts: 25,918
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From: Madison, WI
They give like no credit to the stock girdle that's in all B18C blocks. Sure, the Z10 one is nicer but I've never heard of the stock one failing or causing any problems. The only application where I'd say to go out and buy one of these is if you're using a longer stroke than a B18C (i.e. LS/CRV crank & rods). Even then, if you shell out for some forged rods--which generally come with ARP bolts--the girdle is kind of unnecessary. Eagle rods are like $365 and Crower "econo-billet" rods are about $400, so I'd be more inclined to just beef up the rods and call it a day.