BMcD

I am looking at a hydraulic roller cam with 24x duration @50 on both intake and exhauston 114 Lobe Center and .600 lift on the exhaust with 1.6 roller rockers for my LT1. I have the stock bottom end with stock pistons with stage 2 LT1 heads with larger valves and stock compression. Do you feel that valve clearance will be an issue. Does anyone have a similar set up to save me the task of removing the heads to putty for clearance check. Also if I do need extra clearance has anyone notched the piston valve notches without removing the block. Also would the crane gold rollers need grinding for clearance.

Mindgame

The wide 114 deg lsa is definitely gonna help but with that much duration, I'd say that your clearance is still gonna be marginal. If you get at least .080/.100 then you'll be ok. Usually you'd want more like .100/.125 for carbon buildup but I've never had a problem with it a little tighter.
Gotta check to be sure though.

-Mindgame

squinn

I would say its going to be tight, as with my last hyd roller being 242/251 w/ 584/594 I had 100/125 clearance. But why a 114? I would think that cam is going to really want to make power up high.

BMcD

My understanding is that you normally need more clearance on the exhaust side due to valve expansion so hopefully .100 would be ok. If I change to 1.5 rollers I would think this would help the clearance situation.
On the cam you had what rocker ratio where you using.
The 114 was recommended by the cam manufacturer. He felt if the engine was capable of making horsepower up high it would be a better combination. I also have to be concerned about vacume as I am running an A4

BMcD

Steve I have a question for you. I watched your run when you where at Cayuga Ontario and I have to assume you where spinning high rpm to achieve the times you got . Do you mind me asking what type of hydraulic lifter you use . I believe you told me that you had a rev kit which I also have along with Comp 987 springs.

squinn

I ran a Crane lifter with an AFR rev kit, but the problem your going to run into is that the factory pcm will shut off at 7000 rpm. With that cam I was shifting in the 7300-7400 range with it making peak power at 7k and that was with a 108 lc.

BMcD

The cam I was recommended by Comp is similar to their Extreme Energy 294HR which according to Comp has a power band from 2800-6400. The ramp on this cam might be different from what you where using. I presently am using the cc 306 running 12:0s@113-114mph with a 112 lobe center car is fully equipped (AC,stereo etc.)
Thanks for the info on the lifters so I assume that with the AFR rev kit and crane lifters I should be ok for this power range. Do you feel there is much advantage with the cranes over GM factory. I tried to get Comp R Type but they are on back order.
What would be the advantage of a 108 vs 114 lobe center remembering that the car is street driven occassionally with track time most weekends. I also drive to the track.

squinn

From what I understand it will make power down lower, I would think that cam would rev much higher then 6400, more like 7400. You might wantr to talk to the people at Cam Motion, small cam company, very good people, lots going very fast on there cams.

you might look at something with a 110 or so

From what I understand on the gm lifter when you try and run "0" lash they like to come apart cuz of the little clip that holds them together, need something with a harden C cilp.

BMcD

Thanks Steve I gave Cam Motion a call today in Baton Rouge. They will get back to me.

Dr.Mudge

A 244/244 Solid roller has been done, just FYI.

Mindgame

Doc, I don't doubt that it has.... but on what lsa? That makes a difference in the piston-to-valve clearance due to the overlap period. Question is... is the clearance for this app gonna be adequate and that question is best answered with a check. You have to also keep in mind that not everyone runs exactly the same quench distance.

-Mindgame

Dr.Mudge

I am pretty sure it was on a 114. I believe his member name is Vulva, it was on a 93 that I believe was nuked about a year back? Jim (Steve Kim) http://v8beast.homestead.com/ knows him, and visits more often so he may pop in here.

kmook

FWIW I ran a 242/248 585/586 112lsa solid roller on the stock bottom end, with no ptv issues.

BMcD

I would like to stay with Hydraulic Roller so I don't have to change springs, push rods etc. All I am looking for is a little more strip performance without changing a lot of my present setup. As I stated car runs consistant 12:0 which is the bracket I run in but I would like to enter the high 11s stay NA with stock bottom end so I have a little safety margin when running 12:0 brackets. I would also like to stay with my OB1 so it would have to be tunable. Would a 108-110 LSA help my low end power over 114.
Thanks to everyone for jumping in.

Dr.Mudge

114 is better, that reduces overlap at low RPM so your thinking is backwards