I hated to have to do it, but I need some experienced opinions.

I'm doing a build in my 02 Z28 M6, to make about 450rwhp. At the same time I'm trying to keep driveability since this is a 100% street car, and I'd like to be able to take it on long trips and just cruise.

Here's the build so far:
Rebuilt bottom end (new bearings, forged pistons/rods, etc.)
11:1 CR
243 Heads ported by AI (232cc)
Fast 102 ported by AI
TSP Longtubes to TSP Off-road Y
FTP 104mm lid with 100mm MAF

I was looking at the FTI Hellraiser (229/236) but was concerned about how useable 6th would be cruising down the highway. A friend of mine was saying that the 9 degrees overlap would cause the motor to make too little power down low and I'd basically be stuck in 5th unless I was going 80+. I know a lot of that is in the tune, but I don't want to end up stuck with a cam I don't like lol.

Anyone else have any good recommendations? I'm planning on hitting up Tony Mamo once I get the motor back from the machine shop and seeing what he thinks, but I also wanted to poll the masses, since you guys have the real world experience with them as well.

Thanks

 

I say hit up the man that spec cams daily to all different types of cylinder heads/combos and tell him what you want..... Pat G.

 

I do want to respond to one thing in your post. With a 229/236 cam you will NOT be stuck in fifth. That's like saying the motor won't make 60 lbs of torque below 2000 rpm. Lots of guys run bigger cams than that. You could get some bucking in off idle range, say 1000-1200 rpm.

With that said, AI232 heads and that cam should get you pretty close to 450. Talking to Tony about the combination is ALWAYS a good idea

 

As stated above, what your friend stated is not true. Nothing wrong with 9 degrees of overlap at all.

Since AI ported the heads and ported the intake manifold why don't you just call them up and have them spec you the cam? I feel like it would be ideal to have the person who designed the CNC port program for the heads and ported them for you determine the proper valve events to achieve your goals.

Also, if you don't have one already, I've seen folks pick up some power by putting a good merge on their existing Y pipes. I'm a true duals guy so I don't recall all the details but it's something to look into and consider in helping you achieve your rwhp goal.

 

OP, checkout my signature. I'm making 447rwhp through a stock LS6 intake and TB. My cam specs are 232/236 111 LSA. Very similar to Mr. Ed Curtis' Hellraiser cam. The AI heads I'm running are worth about 15 rwhp more than the AI 243 CNC ported 232cc heads (I was told this by Phil at AI), so given the cam specs of the Hellraiser with the AI heads and ported FAST intake, I see no reason why you wouldn't achieve the 450 rwhp goal.

 

I will give you a little different advice than most. I talk to a lot of customers who regret buying a camshaft with too much overlap with a stick shift transmission. The bucking can really irritate some. With that said, you have to be somewhat aggressive to make your power goal. With this in mind, I would make you a custom camshaft. I would do a 230/236 on 115 with about 4 degrees of advance and .621" lift. This camshaft will have a mild lope at idle and should keep bucking to a more reasonable level at 3 degrees of overlap.

 

^^^^OP, this is good advice! And custom costs no extra....^^^^^

 

Thanks for the responses guys. I will definitely keep that custom cam spec in mind.

One thing I forgot to mention, I don't know if it makes a difference but I'm still running 3.42s in the rear end. I may move to 4.10s but I'm trying to keep the ring and pinion as strong as possible lol.

 

It could make a difference. Just mention any changes in your setup when discussing cam recommendations

 

Your rear gearing will certainly make a difference. If you want strong acceleration from a stop with a 3.42 gear, you might choose a lower duration camshaft that will have the torque come in sooner. But, as you might guess, lower duration camshafts will reduce the cars peak horsepower. So, you have to decide what is more important to you, the cars peak horsepower number or strong torque at lower RPMs. Changing to a 4.10 gear can help you have both.

Street car camshafts are often a sacrifice between drivability and performance. The struggle is real.

Easily our most popular camshaft for a great balance of drivability and performance is the Titan 4:
http://store.cammotion.com/the-titan4

At 227/232 on 113 with 3.5 degrees of overlap, this camshaft is the goto for many of our daily driver customers who want strong performance. It has a mild lope at idle and delivers strong mid-range power. It is no dyno hero, but with good heads and a well tuned car can make 450 to the tire.

 

I think Cam Motion has pretty much nailed it with the overlap and gear comments. The overlap really depends on your tolerance but in my exsperiance what cam motion has said is pretty much right on for guys who want a smooth driving car.

 

I suppose if driveability is suffering due to the longer gears, adding 4.10s in later isn't a massive ordeal. I was planning on rebuilding the rear end once the motor and clutch get broken in anyway.

 

3.90 is a stronger gear with the 10-bolt. I'd recommend that.

And I'd do that before any cam.

 

Unfortunately I'm a bit too far in to go gears first lol.