lt1/lt4 1.5 1.6 roller ratios???
02-16-2009, 07:56 AM
#1
Instructor
Thread Starter
Member Since: Jul 2006
Location: walker louisiana
Posts: 237
Likes: 0
Received 0 Likes
on
0 Posts
lt1/lt4 1.5 1.6 roller ratios???
i saw an old post where a person was asking what ratio a lt4 was...and the info there was 1.6 for the lt4 and 1.5 for the lt1...so my question is ---if i have a stock lt1 and just want to add (ADD) roller rockers,, then 1.5s would give me the less friction of rollers and stay with in stock specs,correct.????.....and not have to be cncrnd about spring bind...unless someone can tell me 1.6 with a stock cam is going to add alot of hp;s thanks
02-16-2009, 09:07 AM
#2
Le Mans Master
The info you got there is correct. LT4 = 1.6 LT1= 1.5. If you go to the 1.6 on the LTL1 you pick up a couple of extra HP from the extra bit of lift. The full rollers would reduce friction a little more than just the roller tipped ones. If your valve train is a stock with relatively low mile setup you should have few problems with just bolting on the 1.6s
02-16-2009, 02:23 PM
#3
Tech Contributor
1.6s on stock LT1 springs put them right at coil bind. Some have done it. I wouldn't risk it.
02-18-2009, 03:16 PM
#7
Le Mans Master
Member Since: Aug 2004
Location: Metairie Louisiana
Posts: 5,141
Likes: 0
Received 4 Likes
on
4 Posts
Be carefull...
This is what got me started on a cam swap. I wanted the 1.6rr ($250). No problem. I figured I should upgrade the springs also. If I'm going to upgrade the springs I should probably get some good ones that can handle a future heads/cam install. ($250 for spring kit.) That also means NSA rockers. So now I need 7/16 studs($38), guideplates($16) and hardened pushrods($136). Hell, the lifters have enough miles on them. They should also be swapped out while I'm in there. $123 for new LS7 lifters. New gaskets for the intake and valve covers came to $45. At that point I was up to about $860 for a roller rocker swap.
What's another $300+ for a cam and gaskets. 12-15 more horsepower from some roller rockers or 50+ from a cam swap? hmm.. Of course then I would want to replace the opti and switch to an electric water pump. Then there's the tune, tools, all the gaskets, and a bunch of stuff I'd rather not think about right now. I bet a lot of major projectors start off like this. 
It's a good thing I'm doing the labor myself. I'll wait until next year for the heads.
This is what got me started on a cam swap. I wanted the 1.6rr ($250). No problem. I figured I should upgrade the springs also. If I'm going to upgrade the springs I should probably get some good ones that can handle a future heads/cam install. ($250 for spring kit.) That also means NSA rockers. So now I need 7/16 studs($38), guideplates($16) and hardened pushrods($136). Hell, the lifters have enough miles on them. They should also be swapped out while I'm in there. $123 for new LS7 lifters. New gaskets for the intake and valve covers came to $45. At that point I was up to about $860 for a roller rocker swap.
What's another $300+ for a cam and gaskets. 12-15 more horsepower from some roller rockers or 50+ from a cam swap? hmm.. Of course then I would want to replace the opti and switch to an electric water pump. Then there's the tune, tools, all the gaskets, and a bunch of stuff I'd rather not think about right now. I bet a lot of major projectors start off like this. It's a good thing I'm doing the labor myself. I'll wait until next year for the heads.
Last edited by rickneworleansla; 02-18-2009 at 03:19 PM.
