I am building a 406 for my RS. So far I've got:

KB-139 - KB Hyperutectic Pistons (+7cc)
Eagle 3D H-Beam rods
Scat Forged 4130 Crank
Miloden Splayed 4-bolt main caps

I need to choose some heads. I was originally going to go with AFR's, but I
am now considering Brodix. My engine machinest is partial to Brodix, and he
suggested that I consider them as an option. Since this is my first engine,
I need as much help as I can get. Here are links to the 2 sets of heads I
am considering:

AFR - http://www.airflowresearch.com/chev195.html

Brodix (the one he suggested) -
[url]http://www.brodix.com/Catalog/Heads/Smallchevy/ST_STD_PKG-1/body_st_std_pkg-
1.html

 

What is your goal? How many HP, what ET, what class, whatever. Is it supposed to be a daily driver, or a Saturday night sleeper, or a trailered race car? Do you have a budget?

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"So many Mustangs, so little time..."
ICON Motorsports

 

RB right, we need some more data. Gearing and such.

But, you don't want to mess with the std head for a 400. Is basically an emission head. It uses a small port, very little intake port volume and lame valve spring sizes. Not much of an improvement over stock.
It really does not even directly compare with the AFR195. The -8 FSH is better but still not worth the trouble. 400s at least need the T1 (and it's kind of old now)

Check this thread:
http://web.camaross.com/bb/Forum13/HTML/004136.html

I would first see if you can find what chamber volume will put you at the compression you want without milling.


[This message has been edited by jcb999 (edited July 12, 2001).]

 

Sorry about that guys. This needs to be a daily driver. Planning on 11-11.5:1 compression. 3.73 gears. Revving at the most 6500 rpm, I dont want to break anything here. I would like to be putting out ~450-500 hp at the engine. I am going to use the Accell SuperRam for the fuel injection, and I plan on running mid 12's (I hope). Hope thats enough. Thanks guys.

[This message has been edited by Scott_92RS (edited July 12, 2001).]

 

The SR really likes velocity. I would go with the AFR195 or TFS195s and a cam with about 220 degrees intake at 050". Get as much lift as you can especially on intake.

Look at page 12 on this link.
http://www.lingenfelter.com/main/lpepdfcat401.pdf

The cam was designed especailly for the SR intake. I think they started with a set of T1s and CNCed them.

If it is truly your daily driver and you will use 92 pump gas, I would get closer to 10.5 to 1. A cam that has really short duration (less than 220) will really raise cylinder pressure (when combined with an LSA of 112 or higher) and anything more than about 10.5 to 1 will probably be very close to detonation.

[This message has been edited by jcb999 (edited July 12, 2001).]

 

In my 388 buildup with flat-tops (Net 10.9:1 CR) the dude told me to send my 2050 compucam back and get at LEAST 230-234 degrees of duration @ .050" lift on a 114 LSA to stay away from bottom end detonation. I'm using the TFS195 heads. He also recommended me to use a single pattern cam with the AFR's or TFS heads because they have a better intake to exhaust flow ratio and a split pattern cam isn't necessary unless nitrous or other adders are used. Now with vortecs or stock heads a dual pattern IS recommended since they have sucky exhaust flow. Just info I got, don't stone the messenger.



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'88 Camaro RS 2.8L
'88 Formula 350 (Too many mods to list...)

 

Pretty sound advice I would say. Increasing the duration by approx 10 degrees and widening the LSA by 2 will have the basically the same net effect to keep cylinder pressure around 200psi (the sweetspot for 92 pump)

I tend to agree with the single pattern statement, if it was not for an exhaust system (i hate those things). Once you put that on, it kind of kills some of the benefit of the late design heads. I like to go with a cam that has near the same lift on exhaust (this keeps exhaust velocity high) as intake but i shoot for about 6+ degrees extra exhaust duration at .050.



[This message has been edited by jcb999 (edited July 13, 2001).]

 

Thanks for all your help guys. I am still leaning towards the AFRs for 3 reasons.

1) They seem to flow right up there with the Brodix
2) To get a similar flowing head from Brodix, it would cost a lot of money
3) And I have a guy that can sell me AFR heads at his cost, he makes no profit.

I am just concerned because this is my first engine. I dont want to skimp on the heads, and have my engine not perform like I expect it to. If you have any more suggestions, please put em here! Thanks again.

 

the AFR's look like a good choice to me. i would agree with the guy who said to get a bigger cam, though. my cam is 240,246 with a .507/.510 lift. it is my daily driver and the cam is not too big. the compression you want is going to be too high for a street motor. stick to 10.5 as an upper limit to avoid $4.oo a gallon gas.

i think you should get into the mid to low 12's easily. mine runs 12.20 on slicks.

[This message has been edited by 406 S10 Man (edited July 13, 2001).]

 

I spoke with a guy over at Lingenfelter, and he told me that they have used all kinds of heads, but the ones that work best are the 88-91 Corvette Aluminium heads, with their port and polish job. They want $2375 for these heads! I could pikc up a set for $450, and send the heads to them, and for the low low price of $18xx, they can port and polish my heads. Sounds like they just want to sell me something. I have heard that the Corvette alum. heads are very good heads, but it sounds to me like the AFR 190's would be a better choice. The Corvette heads come out to have 2.00" / 1.56" valves, while the AFR's have 2.020" / 1.600" valves. The Corvette alum. is only 182cc's, while the AFR is 190. I guess what really matters os flow numbers, but Lingenfelter donest have them on their site. The flow numbers on the 190's are good, but I think I am looking for something more. The AFR 210's look nice, but AFR's site says they make power from 3000-7500 RPM, I only plan on seeing 6500, and being a street car, 3000 sounds a bit too high. I dont quite understand what a stall converter does, but could I posibly get a 2600-3000 stall converter so I would always be in the powerband? Thanks guys

 

Scott....I have heard good things about the corvette heads lingenfelter sales. But they are way over priced.

I would go with the AFR 190s if money wasnt a problem they are a proven combo with the 219 accel cam and SuperRam intake. The 195s are for a victor style intake opening. With the 219 cam and AFR heads you should meet your goals. I think you will be fine with the 11.1 compression with the aluminum heads on pump gas. you can run a full point over iron. I had over 10.1 on my 406 with iron heads and had no real problems with detonation.

If this is a street car and you are going with the SuperRam. Stay between 219-230* of intake duration to stay within the RPM range of the intake. This info is coming from an Accel manual I have. I would pay the price and use one of the Accel cams. They were designed for that application. I would use the 219 if you are going for the roller. Or the 213 its a flat tappet cam. If you dont want to spend the money on the roller.

I think the Track 1 have a 215 intake runner. IF that is true they might be a little big even for a 406. Using the SuperRam...they would work well on a carbed motor with a single plane/RPM type of intake. But I think the 190s would work better with the SuperRam, even if it is a 406. It still is a volosity/torque biased design IMO.

Good luck!

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Black 90 IROC, L98, A4, 323 gear. SuperRamed 406 in the works!

 

Would the 195's be better if I were to match the ports to the intake?

 

The 195s are not really intended for use with ECM-FI combinations. The 190s are. 195 just as a little higher intake roof. The 190s can be obtained with exhaust crossover and are really the emission version of a 195.