BWilson77080

hey guys, im lookin at buyin some new heads here before too long, and wanted to know if 1.6 roller rockers can be used on stock valves, and if so, is there any gain to it (is it worth spending the 200 or so on them).
also, would they still be emissions legal? gotta stay with emissions since I live in texas (bastards).

thanks guys

Beast96Z

iTrader: (21)

If you buy the rockers, make shure it has at least a fresh stock spring or preferblly a hotcam spring on it. Increasing the lift will test the limits of a worn LT-1 spring. 1.6 rockers in bolt-on applications are usaully good for about 10 rwhp, and they accompany everything you do in the future.

Savageite

Well my friend has put the 1.6's on his 94 Z with stock springs and hasn't had any problems yet. But most people say to upgrade the springs.

BWilson77080

so next question...how much would i be looking at to replace the springs as well? and do they entail a valve changeout.

Beavis5.3

Only issue with going to the 1:6 ratio rockers is checking your valve seal to retainer clearance. When you put longer ratio rocker arms on, it's just l;ike putting a bigger cam in, you end up with more lift at the valve. The LT-1 heads have a fairly tall valve guide in them, so you need to check and make sure the extra lift the rocker arms give you won't causing any interference between the bottom of the valve spring retainer and the top of the valve stem seal when it's installed on the head.

You can get a good set of springs to fit your LT-1 heads for a low price. I used a set of Crane's 96802 springs on a 92 Chevy pick-up and they work great. I set them up 108 lbs. @ 1.800". This was with a flat-tappet hydraulic cam. If you set them down to the normal 1.750" height, it'll give you a great seat and open pressure for your stock hydraulic roller in an LT-1. Plus, it gives you enough lift to take the 1:6 ratio rockers if your heads have enough clearance. Crane has a couple of other springs that cost a little more but will also work in your application.

BWilson77080

so would this work..they are springs from a production LT4 and ZZ4..would i have to change anything else if i went to these? thanks.

GM PART # 12551483
CATEGORY: Engine Valve Spring
PACK QTY: 1 CORE CHARGE: $0.00
GM LIST: $9.05

DESCRIPTION: VALVE SPRING
This single valve spring was used on 1996 LT4 Production Corvettes and ZZ4 crate engines and has .525 lift. Technical Notes: Single spring with 1.32" O.D. and 1.22" solid height. The pressure at installed height IS 101# @ 1.78" with 332# the average rate of pounds per inch. Use with retainer P/N 10168424.



thanks for the ton of info Beavis

BWilson77080

whoops, didnt mean to copy and paste the whoel description :~

Beavis5.3

Need to check, those sprngs for the LT4 and ZZ4 are 1.320 like you said, but as far as I know the LT1 spring pocket is 1.275 like a normal small block. If your pockets are this size, then those LT4 springs won't work without machining the spring pocket, then you get into a whole other set of issues.

BWilson77080

o ok i thought most parts with lt4 were interchangable.

onyxxtreme

iTrader: (4)

from what I remember the "LT4 Hotcam Kit" is made for LT1's, which use LT4 springs (also rockers, etc)
A friend of mine has that kit on his 93 TA, and his heads are stock LT1's
Scoggin Dickey sells all that stuff cheaper than anyone else, including Summit and Jegs....and they are a sponsor --->

Damian

iTrader: (89)

I've installed tons of 1.6's on stock springs. They will wear quicker, so I would recommend a new set of springs early down the road, but they will go on without a problem..

josh