SDPC says "For use with 1.6 Rockers" with the LT4 cam. I dont see any reason why they cannot run on 1.5's. I am just wondering why they would say that.

Any thoughts?

 

They say that becuase the advertised lift of that cam is used with 1.6 rr's. You can use 1.5's with no problem what so ever, but the lift will be slightly less. (dont remember the mathematical formula off the top of my head)

 

Thats what I thought. What do you think about the ZZ3 cam?

 

What are the specs on it?

 

I have used the LT4 cam in a few small blocks and it makes very good power. YOU DO NOT NEED 1.6 ROCKERS they just used them on the Vette LT4. Take .030 off of your lift and that will be your cam spec. Nothing else will change. I ran one with Vortec heads on a 350 and I fell like I was making around 330 hp. I am going to put one in my 305 TPI in a couple of weeks. If I can help anymore please feel free to ask.



Brian

 

to state what already been said, u dont need to use 1.6 rockers, i thought it was weird they always gave specs for the 1.6 and on every other cam gave 1.5's but i just got my lt4 cam and i plan on using the stock valvetrain, at least till i get my new heads next year...check out ebay, i got my cam for 60 bucks!

 

We had a 1996 LT4 Vette a couple years back and the reason they give those specs for the motor is that is comes with 1.6 full roller rockers. The trick to it is if you measure the lift specs of the LT4 with 1.5 rockers the cam is only slightly larger then the much cheaper LT1.



Brian

 

ok, i have been wondering this for a while, i have a hot cam sitting in the garage that i was gonna use in a 350 for my car, but in the meantime i was thinking of using it in the 605.

now my question is, will the stock springs in the 305 heads support enough lift to use the hot cam, with 1.5 rockers? or do i need bigger springs?

yes its a tpi, not tbi

 

wih the lift on the hot cam, ud def be better off with new springs, if not need them(depending on rockers), u can use 1.5 rockers tho i am sure of...
1.5 rockers lift - .492/.492
1.6 rockers lift - .525/.525

 

90iroc5spd:::: You will be fine with the hot cam &1.5 rockers on your valve guides however you springs will bind with max lift if they are week. THere is a remote chance your springs will handle it. I can't see them holding up to the extra lift of the 1.6 .525 lift. I can tell you I removed my LT4 can and put in the LT4 Hot Cam and there was a huge power gain and idles with 14inches of vac @ 750RPM




Brian Felts

 

thanks man, i was wondering, i have a hotcam and no springs, i was gonna run the 1.5 stock rockers, looks like i better get some springs