Ok, here is the situation, I have a fresh rebuilt 406 with a comp cams 292H cam in it. (244 244 .501 .501) With my AFR heads this will be around 10 to one compression. I also have 3.73 gears I could install if needed. I want to replace my 350 with this engine and use an LT1 intake. I know about the flywheel and dampner intricacies. The rest of my mods are in my sig and I will have the ability to burn chips soon. Now, I could switch to a roller cam and buy the hot cam but that adds up quickly. (cam, retro lifter, button, chain, etc.) I have seen an article in CHP where this cam peaked HP at right around 6000. Seems like a reasonable RPM to me. So is this cam too big? Opinions??

 

Naa, that'll be just fine for your 406, I'm running the same cam in my vette (with 1.6 roller rockers) and it is smokin' quick. Good torque and horsepower. I usually shift around 6500 rpm.
John

 

Use the 244/244! I'm calling 11's right now on motor once you get it tuned.

rhuarc30, what's that Vette running in the 1/4?

 

Surely, someone else has an opinion??

 

Damn dude, that things gona haul A$$! Good luck, can't wait to get mine done. YOu gonna run a 406 with a T56?? Is that possible?

 

too big for a 406? no way

 

Yes, I am going to run T-56 with a 406. All you need to do is buy the proper flywheel. Also, I am concerned with the 110 lsa that this cam has. Any opinions on the that? Should I just spend the $$ for the retro-fit roller?? Thanks

 

A roller cam is always a much better choice. With the roller The ramps (blast the valves open a quicker) on the cam are a lot more aggresive than with the regular 292 cam!

 

I think the roller-retrofit swap isn't worth the money for a few horsepower. You can call comp cams and have them grind that 292 cam on a 112 or 114 lobe center if you are worried about idle.

I ran their 286 cam in a 355, and I thought that cam was mild, so the 244 in a 406 won't be big at all. I only pulled 10" of vacuum though, so you might want to get it ground on a wider lobe center.

 

Did you run the cam with a carb of FI? Mild? Like girlfriend driveable??

 

I ran it on a carbed 355. It was girlfriend driveable, but she never liked the sound of the flowmaster muffler. It was pretty loud. Never had a problem with the cam, it sounded wicked in the cold mornings with the flowmaster. I used to stand behind the car before going to work in the morning just to hear the lope.

Make sure you run 10.5 compression with aluminum heads and as close to 10 as you can get with iron heads and a good chamber. That will help with the vacuum also.

 

GofasterFirebird - Why do you list your ET as uncorrected? Didn't you run the car in Ohio?

For what it's worth, I would opt for the roller cam. My choice for the 406 if you are concerned about idle vacuum would be a Comp XE 230/236 @ .050, .510/.520 ground on a 110 lsa. The added cubic inch will tame a larger cam. If you can live with a little lope, go with the 236/242 cam.
www.geocities.com/dzperf

 

See, I am just concerned with getting the car to run correctly. Any hints?
Also, yes ran in Ohio. I just don't like corrected times. I think the correction factors are flawed. Corrected times are cheap horsepower. Even though a correction factor for me would only be one or two tenths.

 

ttt

 

If you are using the 730 MAP system for tuning, you should be OK.

If you are running the AFR 190's, you should raise the compression to 11:1. The 244 duration cam will bleed off some cylinder pressure at the lower rpm's.

I don't know what you want to hear, but like I said before, the price of the roller retrofit kit is a bit much for me. For that money, I'd have the AFR's ported and milled and just run the flat tappet cam. Flat tappets have been around for years, ain't nuthin wrong with 'em.

 

I am not worried about bleeding pressure off at part throttle!! I can turn my timing down. I just don't want to detonate at full throttle or run race gas.

 

I'm running ported AFR 190's and my compression is 10.94:1. I run on 93 octane. If you are burning your own chips, you have control over the timing and fuel curves, and you'll give the motor what it wants.

If you feel safer running 10:1, then that's your choice.

 

How did you calculate 10.93 to one? What is your deck height? Flattop pistons? What is your combustion chamber size??

 

Deck height is -.025, TRW flatops -5.3 cc valve reliefs, 65 cc chamber heads, .026 head gasket.

Go to yahoo and type in compression ratio calculator, and you'll get a ton of them.

 

Guess what?? You barely have 10 to one compression by my calculations. Not the 10.94 you claim. 785 cc goes into 80 cc only 9.8 times. Ok, so you have 785 cc swept volume, 5.3 cc valve reliefs, 5.22 cc in deck height, and 5.43 cc in head gasket thickness, and of course the 65 cc combustion chambers.

 

ok, let me revise that. I made a mistake.

5.22 cc for deck height
5.3 cc in the valve reliefs
5.43 head gasket
65 cc chamber

equals 81cc


then total swept volume equals per cylinder=865 cc

so yes, you have 10.6 to one assuming zero crevice volume, and assuming that your head gasket has the exact same diameter as the bore. Both of which never happen. Results? Maybe .3 cc for crevice and 1 cc for the bigger head gasket.

 

So what's your point dude?

You are the one who's scared of running compression, not me.

 

Who said I am scared of running compression? I am just trying to be cautious and debate the point that my big I am not worried about bleeding compression at idle with the big cam.

How fast is your car? In the quarter? Trap speed?

et??

 

13.06 @ 106 before the new combo.

 

g tech? track? what was that with?? what is the new combo?

 

13.06 @ 106 at the track with 9.1 compression, Crane 2032 cam, AFR 190's, SLP 1 3/4 headers, 1.6 rockers, superram, 58mm TB, 2400 stall 12" convertor, 3.27 gears, SLP 3" 2 on the left.

New combo is fully ported AFR's now at 207cc, LPE219 cam, ported superram, SLP headers gasket matched and coated, higher compression, Yank ST3500, 3.70 gears, N-W 175 nitrous kit.

 

106 seems slow for your mods. Custom chip?

 

Ed wright. I burn my own now. The old combo had bad lifters. Had I known then what I know now, it would have gone faster.

 

that new combo should hustle! ttt

 

ttt

 

Thumbs up on the ST 3500 converter, a better converter in my opinion. I would like to see more thirdgenners running them.