wolverine8490

Ok,

So I know there are a ton of cam threads out there. I have been doing my research, but just want to get some opinions. I have a 96 GT with full exhaust, 3:73's, special forces tuning, and an LC-1 wide band. I am wanting to run low to mid 12's NA. I am bouncing back and forth on stage 1 or stage 2 CMS cams. I have watched multiple you tube vid's on the 2 different cams. Some I see barely idle, and others I see sound awesome. I also read the 12's on a budget from Texas Hot Rods which they used stage 2 cams. I have no issues with changing out my springs (even though it sucks) and I plan to also install some long tubes, and PI heads.

My question is, should I do stage 1 or stage 2 cams. It is no my daily driver, but I love driving it. If anyone can throw me some advice, it would be much appriciated.

mrtstang

Notch the pistons when you do the PI heads, and do the stage 2's. This way you won't have to "possibly" retard them (thus losing potential power) to make them fit. This will help insure that there are no PTV clearence issues as well.

SilverGT03

make sure if you do the stage 2s you get new springs

wolverine8490

I have heard mixed opinions about notching. They say you do not have to, and I hope I do not. I 100% plan on new springs though.

nickmckinney

With CMS stage 2 you can just modify the stock valve or install an aftermarket valve so they clear with enough safe clearance. No need to notch the piston with this cam if you fix the valve problem. Here is a picture of the stock valve next to a aftermarket valve showing what I am talking about:

wolverine8490

Is this only if I use the PI heads with the 96-98 block? What if I stayed NPI heads? Would valve clearence not matter then?

nickmckinney

NPI heads have 0.1" more clearance than a PI head, but the valve retainer hits the valve seal at 540 lift. Bullet is the only company with a good cam for NPI heads as they use 525 lift for the Stage 1 and Stage 2 cams.

Mustang_NTriangle

I recommend you go with CMS stage 2 cams don't go with stage 1. You will need up grade your springs which is a good idea. You do not need to cut fly your pistons or modify your valves to fit CMS stage 1, 2, or 3 cams.

nickmckinney

Well I have used the CMS stage 1 and stage 2 cams and the stage 2 will fit with 0.005" of clearance if the timing gears are zero (which few are) Any advance in the gears the pistons hit the valves (been there done that).

Mustang_NTriangle

So it is different with PI heads then vs NPI interms of clearance? I am installing mine next weekend so this post is making me a bite nervous.