building a 406, not anytime soon. but it has KB 11:1 domes(64c) 5.7" rods, the heads haven't been purchased but something along the lines of about a 210cc intake runner(give or take 10 cc's) and a 2.02-2.05 intake valve with a 64cc combustion chamber. I'm thinking the dart iron eagles.

the intake is an Air gap, unless another kind is highly recomended.

motor is going in my 91 camaro with a 700r4 and 3.42 gears. (possibly if I'm lucky a 200r4)

just curious what kind of cam you guys recomend and why? I would like to make 475-500 hp hopefully.

or mid to high 11's in the quarter(taking in that i have some traction mods done)

I do have a comp XE-274 right now to be thrown in, but find that is probably a little small????


thanks for your recomondations hopefully

 

Here's my stab at it.
1. A.F.R. 215 competition heads.
2. At least 850 cfm carb.
3. Here's the cam specs I'd use:

Lobe Seperation angle - 110.0
Intake centerline - 109.0
Intake Duration - 236.0
Exhaust duration - 242.0
Intake lift - 0.575-0.590
Exhaust lift - 0.600

My reason is simple. Valve to piston clearance, which you might want to check. The lift isn't as important as the duration. This cam should get you just over 500 hp and around 500 lb-ft of torque. The best thing is the maximum hp and maximimum torque outputs are a mere 1500 rpm apart, which means this motor will have a good power band. For a torque converter, I'd go with a 3500-4500 stall speed. Hope that gives you a good start.

 

what is your goal with this motor? street? strip? street/strip? strip/street? I think you'd do better with a smaller 180-200cc head in a street/strip type motor ...yes, even on a 400. What type of cam would you wanna run? hydraulic? solid? hyd/solid roller?

A friend of mine has a killer street/strip 400 combo that is very cheap to build. 400 stock crank and rods with crappy KB pistons (about 10.8:1), unported Vortecs (170cc, 1.94/1.50 valves), Super Victor intake, 750 Speed Demon. For a cam its got Comp's Xtreme Solid 282 which is 244/252 @ 050, .520/.540 lift, 110LSA. Gearing is 3.42 with a 3500RPM stall. This car weighs 3500lbs without driver and has been 11.70 @ 113mph N/A with very little effort and can even pick the tires a few inches off the ground. DAILY DRIVABLE if you dont mind sucky gas milage he drives this car hundreds of miles a week and runs on 93 octane pump gas. On a small nitrous hit this car has hit enough mph to run 10.70's (just no traction!)

Just food for thought. Why spend thousands of dollars on expensive heads like AFR when you could probably reach the same goal with something much much cheaper.

 

You make a good point Iroc88. Street manners are important. The combo I listed will have better street manners because it's not cammed so hard. The reason I suggested the A.F.R.'s is because of the flow rate. 400's like every other engine, want to breathe. The 215's will give it every opportunity to do so. It's nice to see that your friend's combo works pretty good. I'd love to hear a sound clip of the motor. I'll bet she sounds mean. The combo I listed above should be good for low 11's, but with a cam like your friends, I'll bet she'd grab the high 10's without the nitrous hit. I went with a smaller cam for street manners, since the heads breathing abilities would help compensate for the cam. It seems your friend cammed the motor to make up for the engines lack of breathing capabilities. Don't take that as a slight, if it works, who am I to say anything. As a matter of fact, I applaud his ingenuity. I'll end this post by saying the poster should take your suggested route if he's on a budget. If he isn't, then I leave it up to him to decide what he wants and how much is too much to pay to get it.

 

yes I'm somwhat on a budget, the AFR's are definatly somethign of a treat. the DARTS are something a little more realistic for me. its going to be street car, gas mileage dont matter. the cam choice would probably solid or hydraliic, i'd go roller but again thats an extra 1000 to go that route. I'm 21 live in my own, and go to school part time and work full time. that might give you a better idea that I dont have the cash to blow. I've still invested probably 3 g's into the motor so far (canadian)

cheers

blake
ps thanks for your input guys 500hp sounds fun

 

In that case, you'll want to use a solid roller cam for the hp boost. It's only around 20 hp, but on a budget you need every break you can get. You might want to check out e-bay for a little more savings and a couple more options. I've noticed a lot of stores there that carry name brand parts at bargain prices. For example, I found the Edelbrock RPM Air-Gap unpolished for 149 bucks at racer's outlet. I hope the information we dropped in your direction helps out. Above all else, have fun with it.

 

hmm what about the hydraulic flat tappet XE 294? 294 intake duration and 306 exhaust .519" intake lift and .523" exhaust with 110 lobe serpation

 

never built a motor. and am wondering whats the pros and conts about hydrualic and solid lifters.

from what I recall reading. I think the solids are better for performance, but you get valve lash after say 300 miles?

cheers
blake

 

Solid lifter's require frequent valve lash adjustments while hydraulic lifter's will easily get to 75-100 thousand miles before needing adjustment. The downside is that hydraulic lifter's begin to experience valve-float at around 6200 rpm's while a solid will soldier on far above that with no valve float. If you don't want to make frequent lash adjustments, I'd say go with a hydraulic that will keep the power-band under 6000 rpm's. You'll spend less time under the hood and more time enjoying your car. I only recommended the solid for it's ability to make maximum power in your combo. When you decide which route you want to take, shoot a cam description my way. The most important thing to remember when choosing a cam is to be honest with yourself about how much time under the hood is too much and how much power do you really need.

 

I was running a Comp XE294 hydraulic flat tappet cam in my 406. It ran 11.86 on a bad air day with that cam.

 

well I'm not a motor guru, take in knowledge basicaly by reading people experiences on a this forum and a malibu forum.

I think I'd prefer not going under the hood that much, this is a park and go kinda of car. I willl probalby be driving it daily in the summer time. so I dont want to be having to adjust the valves on it all the time. the roller like I said, is what I woudl LIKE to do. but realistically I should just stick with my hydraulic, because I dont even have heads yet. the price of going to roller set up would be the same as a hydraulic and almost enough to cover a set of iron eagles(shopping around on ebay). I think I will be more than happy with it. there is really no need fo rme to make 500 hp or 475. I have a 454 big block which is a true street monster motor, which still needs to be done. if I need more power I can always finish that(shoudl realistically make about 720hp)

so any other cams that you recomend that are similar to the extreme energy? you just hear a lot of good things about them. Anything of the Crane energizer cams? custom ground cams?


I dont have to worry about air care stuff(emmisions)

 

What exactly is valve float and how does it negatively effect your performance?

 

Valve float is a high-rpm engine condition in which the valve lifters lose contact with the cam lobes because the valve springs are not strong enough to overcome the momentum of the various valvetrain components. The onset of valve float prevents higher-rpm operation and extended periods of valve float will also damage the valvetrain.

 

If you want to have a special cam ground, I would go with something along these specs:

Lobe Seperation - 110.0
Intake Centerline - 106.0
Intake Duration - 240.0
Exhaust Duration - 246.0
Intake Lift - 0.580
Exhaust Lift - 0.600

This will have gobs of torque all the way up to around 4000 rpm's and a maximum hp rating around 450-470. The power band will top out around 6000 rpm's with an 850 cfm carb and the Dart Pro 1 heads. This post is for Blake, to answer the question he was asking. The cam Blackroc endorsed has a little more duration, but it should be a monster cam too that bears looking into. The only cams I've ever dealt with are competition cams and some G.M. Performance cams. I can't comment too much on the other cams with experience in using them, but I'm sure somebody here must have used them; ask around.

 

Actually, based on everything Iv seen, valve bounce is more likely what happens. Very few Ramps have the velocity at the top of the lobe to propell the lifter into the air. The valve spring seat pressure is usually insufficent and the valve bounces on the seat.

 

Bounce would be a good description, but float was the technical term given to this horrible condition. Why they call it float I'll never understand.