the mods on my car are below. I think I wanna go with something harder than the hotcam , I was thinkin cc306 , cept I wanna keep my roller rockers since I already have them . Can stock lt4 heads and intake keep up with a cc306 on 1.6 rr's ??? I of course will replace the springs and lifters but I figure the rockers are worth keeping. cc306 should have a lift of .544 / .576 on 1.6 rockers . Lemme know what you think . Also spring recommendations would be highly appreciated too ( I dont want to have to machine the heads to do so).
thanks , Justin

 

I'm sure the heads will work if that's what you mean. They would be better if you had them ported of course though. For valve springs I think the most used right now are the CM612 springs. They require no maching if I read everyones post right. I know I LOVE my 306 cam. Good luck.

 

ttt , im sure someone knows more about this . I just wanna know if Id be wasting time having that much lift on stock LT4 heads or if they would work very well with that.

 

I used Comp 987's with different inner springs on mine. The lifters should be fine, maybe take them apart and clean them up. I had plenty of piston to valve clearance when I did mine. As a matter of fact, I only have 50cc chambers on my heads because they have been cut down a few times.

My Hotcam stayed in my car for about a month. I pulled it out and went with the 306. Mine made power until 6900 rpm. Some people call bull**** on that, but it can be done. I have a dyno sheet somewhere, let me see if I can find it.

I layed down 380 something rwhp and 370 ft/tq. I don't remember exactly though.

Do it, you'll be happy.

 

I am with you there!! I have had mine up to at least 6500 rpm and it was puling like a madman!
What are your mods to get you to that hp and I would love to see that dyno too! I am going to run mine sometime in the next couple of months to see where mine is.

 

Long tubes, 3.5" exhaust, XR1, underdrive, digital 6, 52mm ported TB, ported intake, here's the catch though, I raised my intake runners a little so I got a little more power out of that, moroso cold air, ported maf, no gears, some weight reduction, and I can program my own car so that helps.

I spent about $1500 on my heads. I is waste though. Stock castings only flow so much. Time to invest in some AFR's and get them ported again.

 

yeah but what about the lift number ill get using 1.6 rockers with the cc306 , is anyone running that ???

 

.544 and a .576 is not that much. Do it and be happy. There is plenty of piston to valve clearance.

 

That is what i am running no probs...love the cam, you won't be diapointed.

 

I'm not trying to hijack this thread but I have a guestion that is somewhat similar to yours. I'am currently running the hot cam kit on stock heads and was wanting to switch to the 306 too. My question is that the sa1.6 rr that come in the kit are only rated to handle .575 lift. The 306 with 1.6's is .576. I know that it is only a difference of .001 but is that enough to make a difference. I have done several searches on this but I was unable to find an answer that addresses this issue.

 

are you talking about the 1.6 rockers that come with the lt4 kit ??? They are only good to .575 lift ??? that I didnt know can anyone second this ???

 

I think the springs are what are what are good to the .575
I have never heard of rockers being restricted to a certain lift other than if you go to an extreme lift then you might have to check stud clearance at the top and bottom of the lift.

 

i think the springs arent any goof for anything with more lift than the hotcam .525 max on the lt4 springs I think

 

On the install guide that cam with the hot cam kit it says under the the rockers section that they are only recommended for use on cams with up to .575 lift. You are right though, the lt4 springs are nearly at coil bind with the hot cam kit. Also in the year one catalog it shows the gmpp 1.6 sa rockers as only good to .575 lift also. I'm kind of a newbie hear so I hope that I am wrong because I really would like to use them if possible with the cc306.

 

I would say then that since it is only a .001 difference I would install the cam and then slowly turn the engine over (after you get the heads and rockers and everything done) and see if they are going to bind at the top and bottom of the lift. I am not a pro on these as I bought some used ones when I did my cam swap and I didn't bother with worrying about it. If worse comes to worse and you havn't bought a cam yet and don't want to replace the rockers, go with the cc305 its a 540/540 lift and you would be well under your maximum. Just a thought. Or keep the hotcam and continue to save until you can get some crane gold R/R's that will allow that monster lift of the 306 LOL