Cam - Head - 470 Selection

OK All, Thought I would pose this question and seek a bit of advice.

Working on a 470 build, 440 source kit, predicted compression at 10.4 with 84 cc heads. Block has been squared, line bored, and other usual work.

Motor is going behind a TKO600 and will be used for Auto Cross, Drags, and street fun and cruising.

Question: I plan on using 452 heads which have been surfaced, 2.14/1.8 valves installed, back cut and 3 angle job. When they do this, they hog a bit off improving the flows a bit, not sure how much.

Exhaust is TTI 2 1/8's

As for intake, probably using a super Victor - open plane type intake. It will start off as a carburetor, but currently working on a Megasquirt III setup. This is what I want to build for.

Engine target will be 550ish. Keeping the option open for Nitrous also.

What I am looking for is a cam set up. Predictions are for engine to flow to about 6800. I am looking for long tern reliability and budget, so I believe I would like a hydraulic roller. Here are some of my concerns and thoughts:

1. Heads are the weak link.
2. Fuel Injection - is there a better profile to fit fuel injection? What is it and why?
3. What cam and why?
4. Will a hydraulic roller make it to 6800 without issues

My current cam selections have been through Howards and Hughes, they seem to hit more of the stable profiles with lift, and some with split duration. Cams I am looking at:

CL723235-08: http://www.summitracing.com/parts/hrs-723235-08

SER3442BL3-10: http://www.hughesengines.com/Index/products.php?browse=search&search=SER3438BL3-10&partid=30772
- Hughes, I spoke with Dave, this is the cam he selected.

At this time, I like the Howards much better. What are you thoughts?

Those heads aren't doing you any favors. I would definitely get a better set like Indy's or even Edelbrocks. I prefer the Indy heads. Why not make more power naturally aspirated so you don't have to spray it. If you are already willing to spend the money on a roller cam, then you will have no problems making 650+ hp naturally aspirated with a decent set of heads. I prefer solid cams any day over a hydraulic cam but either way I would never run another Hughes cam.

452 heads as you describe will probably flow no more than 245 cfm and stall above .500" lift. Your maximum horsepower should be around 5,200 rpm with those heads and then the power will drop off a cliff. It will never get into the effective rpm range of the Super Victor manifold.

You should bush the lifter bores to run a hydraulic roller cam if you expect to successfully wind it to 6,800 rpm, and without an extremely stable valve train it ain't gonna happen. I am unfamiliar with the MegaSquirt III system but many fuel injection systems require at least 8" of vacuum at idle and the lobe separations of those cams you have listed don't lend themselves to excellent idle characteristics. Fuel injection cams are mostly in the 112-115 degree lobe separation range as are nitrous cams.

Been there done that and wrote a few magazine articles on it:

http://www.moparts.org/Tech/Archive/bb/550hp.html

http://www.moparts.org/Tech/Archive/bb/Lobe.html

Just build what I built back in the stone age and you'll be fine. You can get an EFI version of the Victor intake for the EFI build. For the carb build just use a Performer RPM. Sell the cast iron heads and get a set of Edelbrocks. Have them ported if you want 550 honest HP. The hyd flat tappet in my low deck 470 would pull past 7000 rpm but I had top dollar rocker arms and beehive springs. If you use cheap parts there is no guarantee that a hyd cam will pull anywhere close to that.

TTi 2 1/4 exhaust?If that is pipe diameter you should be at 3" or 2.5 minimum.If that is header size you are too big. 2" at most and maybe 1 7/8 depending on gearing and usage.

Follow Andy's advice.

IQ and Andy THANK You for your input. Sounds like the 452's are gone then. As for bushing the lifter bores, we area little past that at the machine shop, so what are other options?

Now for heads, I was looking at the Super Stealths? What are the thoughts on those?

Same with the cam, any thoughts on those? I do want to stay in the 6600-6800 power range.

496 - 2-1/8" SR STEP HEADERS, and the car will be for Autocross, Drags, street use and cruising. 430 gears with TKO600

If you read some of IQs threads you'll see he did a test with the super stealth heads, and they aren't any better than the regular stealth and also require offset rockers.

I would go with a solid flat tappet, I have found that they don't require as much maitnence as some people say and with decent rockers and springs your valvetrain will be stable enough to meet your rpm goals, even though on a motor of your cubic inches the stealth or rpm head will probably be done by around 6500

440dartsport said:

Those heads aren't doing you any favors. I would definitely get a better set like Indy's or even Edelbrocks. I prefer the Indy heads. Why not make more power naturally aspirated so you don't have to spray it. If you are already willing to spend the money on a roller cam, then you will have no problems making 650+ hp naturally aspirated with a decent set of heads. I prefer solid cams any day over a hydraulic cam but either way I would never run another Hughes cam.

Click to expand...

Just wondering why you won't use a Hughes cam again?

Cazbah362 said:

IQ and Andy THANK You for your input. Sounds like the 452's are gone then. As for bushing the lifter bores, we area little past that at the machine shop, so what are other options?

Now for heads, I was looking at the Super Stealths? What are the thoughts on those?

Same with the cam, any thoughts on those? I do want to stay in the 6600-6800 power range.

496 - 2-1/8" SR STEP HEADERS, and the car will be for Autocross, Drags, street use and cruising. 430 gears with TKO600

Click to expand...

I will have a set of eddy RPMs and matching intake for sale shortly when IQ52 sends me my ported heads and intake.

Why do you want it to rev so high?

To avoid having to have the block bushed go with solid lifters. Adjust them (or check them) once a year. Easy..

I'd be glad to send you my bumpstick too free of charge. Car runs 11's and will rev to your desired RPM however it doesn't make peak power there. I run through the traps at 6200 with 4:56 gears.


PS: neither of those cams will make HP or rev in the RPM range you desire nor will they make 550hp in that combo. stay above 110lsa as IQ suggested.

Twayne - Really why I posted was to obtain much more feedback on the heads issue and to hear from members such as IQ - What a wealth of knowledge (Andy and MRL as well -- and many others such as yourself). Also it is to look at logic, cost and performance.

What I see is to get to 6500 and have roughly 550ish HP with sustainable maintenance is a better goal. I want to drive this, enjoy it and be fast enough to keep my underwear clenched but not chaffing. I am also am debating if I should scarp this project and go to a Gen III setup? As for Hughes, yes I would use them but I have to admit Dave gave me simple answers - "this is the cam you need." Is it? IQ actually hit some points on the LSA which reading confirms. So, I will keep doing research until I am in the position.

Rocco - Thanks for the offer, and your right I may be barking up the wrong tree with the hydraulics, your advice is taken on the mechanical. Did the shims work out? Sorry for delay on getting them to you. Keep me posted on your Eddies, I may be in the position for them soon. I am debating on selling the 470 and heading towards a Gen III. How the car doing?

Cazbah362 said:

What I see is to get to 6500 and have roughly 550ish HP with sustainable maintenance is a better goal. I want to drive this, enjoy it and be fast enough to keep my underwear clenched but not chaffing. I am also am debating if I should scarp this project and go to a Gen III setup? As for Hughes, yes I would use them but I have to admit Dave gave me simple answers - "this is the cam you need." Is it? IQ actually hit some points on the LSA which reading confirms. So, I will keep doing research until I am in the position.

Rocco - Thanks for the offer, and your right I may be barking up the wrong tree with the hydraulics, your advice is taken on the mechanical. Did the shims work out? Sorry for delay on getting them to you. Keep me posted on your Eddies, I may be in the position for them soon. I am debating on selling the 470 and heading towards a Gen III. How the car doing?

Click to expand...

550hp is reasonable and it will live happily there. I just don't think you need to spin it to the moon to get there. In regards to maintenance, once a year seems to do me well and I can tell you they aren't far out if at all.

The shims helped. I now have gone to an RMS setup. I'd never build another A-body without one. I really mean that.

Stick with the 470. Your so close and it is a great reliable engine and much easier to work with than the gen III.

My car is doing well

Cazbah362 said:

Twayne - Really why I posted was to obtain much more feedback on the heads issue and to hear from members such as IQ - What a wealth of knowledge (Andy and MRL as well -- and many others such as yourself). Also it is to look at logic, cost and performance.

What I see is to get to 6500 and have roughly 550ish HP with sustainable maintenance is a better goal. I want to drive this, enjoy it and be fast enough to keep my underwear clenched but not chaffing. I am also am debating if I should scarp this project and go to a Gen III setup? As for Hughes, yes I would use them but I have to admit Dave gave me simple answers - "this is the cam you need." Is it? IQ actually hit some points on the LSA which reading confirms. So, I will keep doing research until I am in the position.

Rocco - Thanks for the offer, and your right I may be barking up the wrong tree with the hydraulics, your advice is taken on the mechanical. Did the shims work out? Sorry for delay on getting them to you. Keep me posted on your Eddies, I may be in the position for them soon. I am debating on selling the 470 and heading towards a Gen III. How the car doing?

Click to expand...

Do you have a copy of my book on Big Block engines. It is only $20 at Amazon and it will answer a bunch of your questions.

http://www.amazon.com/dp/1613250924/?tag=joeychgo-20

twayne24365 said:

Just wondering why you won't use a Hughes cam again?

Click to expand...

I went through 3 of there solid flat tappet cams in my 500" motor in a season. They were wiping out lobes and also had a lot of pitting in the cores. I switched to the same grind Comp cam and the lobe issue went away. I don't know if they weren't hardened correctly or if they had a bad batch of cores but I won't run them anymore. I will say that they did make a lot of power though. We made 773hp with a 500" Indy Ez headed motor on pump gas with a flat tappet cam.

Andy, Sure do thank you. Leave it on the tank for a little light reading every now and then.

Read Andy's book more - and then a second time.
I'm not sure why the 550hp level, but to do it you have to give it air and rpm. I think larger MW cross section heads would be a mistake given the autocrossing and street cruising. You only need 280-290cfm and that can be done with good value on a standard wedge sized port. Get Stealths or RPMs with a CNC port or good hand porting to get you the flow you need. I stay away from hydraulic rollers, and any solid rollers get bushings. So at this point I would go with a solid flat tappet matched to whatever head package you end up with.