Need to decide on head work for boosted motor

notchstang92

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Been searching, but all I find is head porting info for n/a motors.

I have a stock 01 motor w/ a stock eaton on it. Looking to forge it and port the eaton. I'm stuck on heads though. Would I see a major benefit from porting my stock heads? I have 98 cobra intake cams and was going to run those with my stock 01 exhaust cams. I know it's not the best choice, but I'm looking for driveability and also in MA we need to pass emissions.

I was thinking 9:1 for compression or maybe a bit higher. We have 93 pump gas here in MA.

Before I spend all that money for port work I want to know if there are better ways to spend my money on head work. Also who does quality head work? I always hear TEA mentioned, but I have no experience with them.

Goals for the car is an emissions legal street car with around 500rwhp. Don't know if this will happen, but guys seems to get around that number with ported eatons. With my numbers now another 75-100 rwhp will put me at my goal. I have more than enough of a fuel system to support this.
 

RPM4DAZ

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I don't know how strict emissions testing is in Mass. But, here in Cal. it is the strictest in the states. There are cam profiles out there that easily go through emissions testing if installed correctly. Aftermarket cams are far better than the factory slow motion ramps. As to your main question. Anytime cylinder head efficiency has been raised it will benefit the assembly. Whether it is normally aspirated or force inducted. When force inducted though, the need to get every little amount of cfm is really not "needed". The pressurized air helps to cover up some inefficiencies in port design/shape. Doesn't cure them, but does help. I myself, am a big valve guy. I believe in running the biggest valves I can and open the bowl areas first. Then if the need arises the rest of the port can be opened to match. In the design of our heads the bowl and the valves are our biggest concerns. Are you planning on using the stock exhaust manifolds? Stock factory cats? What can you get away with as far as cats in Mass? Those are probably your biggest chocking points... My suggestion is to have a good known head porter work the heads as stated above and get a good mild set of cams leaning towards letting the exhaust side breathe. Something say in the 215' @ .050" mark on the intake and about another 10 degrees of duration on the exhaust installed on a 112' l/sep +0'. It would run really nice, idle smooth @ 750-800rpm and the sniffer wouldn't even know... Also, the benefit of above would allow better engine breathing thus allowing a person to spin the blower slower. You have less heat in the air and greater efficiency. You can only spin the blower so fast... Oh, I almost forgot, run your compression around the stock 9.8:1 level. It won't hurt any. In fact it will help keep part throttle torque up and help with the emissions. Not to mention that it will respond more to small amounts of manifold pressure better!!!
 
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RPM4DAZ

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Another thing I forgot to mention. The higher compression level will help keep fuel mileage up. I know we don't build for mileage, but if you can keep it and not lose it.... You wallet will be happier!
 

notchstang92

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thanks for your input. I'd be running cats. We need them here for the visual check. I have the magnaflow hi flow X which keeps the check engine light off. You have the light on or if you turn of any monitors in your tune you fail inspection. Then you get flagged and have to go to a special state inspection place. It's such a hassle now. Longtubes aren't street legal here and will fail a visual check. I think CA is worse than MA, but not by much. I was thinking just sticking with the stock manifolds. We don't really have many great modular engine guys around here so I would have to ship these to someone.
 

fs308

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from na svt on another thread

From na svt
The absolute best thing you can do to your heads is install 38mm intake valves and open the seats up to 90% of the valve diameter, 1.496. At a minumum open up the seats to 90% of the stock valve diameter (if using stock valves) which is 1.45669". These heads suffer from undersize seats and by opening them up you will get significantly more flow.

As for the combustion chamber, enlarge it to the size of the BB head gasket. This will unshroud the valves (a little) and also remove any sharp edges and pockets that inhibit flame travel and lead to detonation.
 

Black*Death

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I have ported heads through MMR. I would say I consistently see 20-30 more HP than others with similar set-ups.

By no means scientific, I am happy with my port job
 

notchstang92

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from na svt on another thread

From na svt
The absolute best thing you can do to your heads is install 38mm intake valves and open the seats up to 90% of the valve diameter, 1.496. At a minumum open up the seats to 90% of the stock valve diameter (if using stock valves) which is 1.45669". These heads suffer from undersize seats and by opening them up you will get significantly more flow.

As for the combustion chamber, enlarge it to the size of the BB head gasket. This will unshroud the valves (a little) and also remove any sharp edges and pockets that inhibit flame travel and lead to detonation.

Thanks for that. I definitely want to reduce my chances at detonation. Now I guess the biggest question is who is reliable to do a job like that correctly? That's my other problem is I don't know who to use and I have read about the Modular Head Shop problems. I have always heard of TEA, but don't know anyone who has ever used them. With all MMR's negative threads lately I am very leery of using them.

I live in MA and these heads are heavy so shipping will be expensive. I also want to have the cams degreed while I have the chance.

Again I'm looking for only 500 rwhp on ported eaton or maybe the snakebite if my research on it comes back positive. If I hit around 510-520 I'd be pumped. I'm at 417 right now on a stock motor.
 

na svt

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That's my other problem is I don't know who to use and I have read about the Modular Head Shop problems. I have always heard of TEA, but don't know anyone who has ever used them. With all MMR's negative threads lately I am very leery of using them.

I use a shop local to me for all my headwork (milling, valve jobs, oversize valve installs, etc). They are very reasonable and since they specialize in NHRA superstock heads their quality is second to none.
 
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notchstang92

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I use a shop local to me for all my headwork (milling, valve jobs, oversize valve installs, etc). They are very reasonable and since they specialize in NHRA superstock heads their quality is second to none.

What kind of prices should I expect for what I need done? I forgot about a machine shop in RI that has a good reputation, but I just want to make sure I'm not getting hosed on the price. These heads are heavy and probably not cheap to ship so I could avoid it I would. I also had UPS destroy a set of 03 cobra heads because they were so careless handling them. Not looking to go down that road again.
 

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