I plan on ordering all the internal parts for a 383 LT1 buildup in the next week or so and i would like to go with one of the cam kits from Cmotorports. I have decided on the 230/236 cam since I am going to have to deal with emissions and I feel that with the right tuning I can get this cam to pass. My question is which version of the cam would be best for my setup? I will be running approx 11.5:1 compression on well ported LT1 heads with an M6. Cmotorsports lists the following cams:

NCC-230HL 230/236 duration @ .050", .560"/.570" lift with 1.5 rockers, .598"/.608" lift with 1.6 rockers.

NCC-230XH 230/236 duration @ .050", .584"/.585" lift with 1.5 rockers, .622"/.624" lift with 1.6 rockers.

NCC-230XL 230/236 duration @ .050", .510"/.521" lift with 1.5 rockers, .544"/.555" lift with 1.6 rockers.

The 230XH has the least amount of overlap at 59 degrees so it would seem like the best for emissions, but it also has the highest lift and extreme ramps. I also like the look of the 230HL as far as lift goes with 1.6RR's but it has 64 degrees of overlap and might be harder to pass emission with.

Any advice on cam choice for this setup would be appreciated.

Thanks,
Rob A.

 

Thats a lot of lift.

 

Id go with the NCC-230XH IMO. Just make sure you have ok PTVC when you get one of these.

 

Would you recomend this cam with 1.5 or 1.6 ratio rockers? The lift numbers start to get realy big at 1.6. Also, at what lift will I start to run into piston clearance issues with stock LT1 heads and flat top pistons?

Thanks Again,
Rob

 

Hmm, well Seth at CM would have more knowledge on what you could probably get away with on that combo and still have ok clearance. I dont want to make any guesses and have you commin after me ...

 

I installed the Comp XE 230/236 cam with the same lobes as the XL cam that CMS is selling. The HL and XH lobes have very fast/steep ramps. The steep ramps are a little rough on hydraulic lifters and may shorten their life. If you choose the HL or XH cam you should seriously consider the Comp R Lifters as well.

 

Yeah be careful with the piston to valve clearance. On my cam I had exactly .060 left which isnt much to play with. I have this on stock pistons.

 

What lift lobes was that with and what ratio rockers were you using? Thanks...

 

hey man I am going with the .598 .608 cam in my 12-1 com. 355
the motor isnt together yet but seth atCMS said that I should have plenty of room so I hope that helps you alittle

 

.3800 intake and .3830 exhaust on 1.6rrs. If you want I can scan my cam card and email it to you. Just let me know. At least I was told it was at .060 when It was put in and its still only on the 350 motor

 

probably wont be able to pass emissions with any of those but feel free to try. if it were me i'd take the NCC-230HL little easier on HR lifters. ported stock heads wont utilize the lift gained over 600 anyhow for the most part its just harder on springs and other things like that. just mho. any of those should make good power though good luck