best cylinder head

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elitesrock2

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So my 340 seems to run out of steam right around 6700 rpm. Cam card states op range of 4500-7500 and my specs are 340 with 11.7-1 custom ross pistons forged, 302,309 duration .654/.655 lift solid roller comp cams cam, X heads with 2.02 valves, harland sharp 1.5 ratio rockers, super victor intake with a 750 berry grant carb on top. Any suggestions on the best heads i could run on this? seems to be what wipuld be holding it back the most
 
Well for starters, your carburetor is too small, IMO.

That said, the "best" heads are relative to what you plan to do with the car. IQ52 would be a good one to chime in.
 
Well for starters, your carburetor is too small, IMO.

That said, the "best" heads are relative to what you plan to do with the car. IQ52 would be a good one to chime in.
Know anyone with a 850-950 you can try. It might be worth a bolt on even if it isn't tuned for your engine combo.
 
Any work done to the X heads? If they are just stock they will flow in the 215 CFM range. Usually the flow tips over at about .500 lift. Maybe a little less. So the head's are holding you back for sure. Carb is small too. 850-950 double pumper is best. No vac secondary with that cam.

As for "good" heads. There are plenty. Ideally what you want, is a head that has max flow that is similar to your cam. For ex if you cam runs to .550, then your head should flow to at least that. Given your cam spec range. You can see here how the heads are holding you back. You don't have the flow from the heads that the cam can do. You're basically "wasting" .150 of lift. I would suggest aluminum heads. Get something that flows MINIMUM 270 CFM around .500 or more. Anything less can be achieved with X/J heads anyways. Make sure they are milled to keep compression up. You ideally want 8.5 DCR (dynamic compression ratio) if you're on pump gas, based on zero altitude. Higher up you can get away with more. With access to better octane, you can do more.

In my opinion, I think you got a very valid setup to test edelbrock victors on. If you got those kinda pennies.
 
What is it your trying to do E.T. wise?
are your heads fully ported now and what do they flow?
Edelbrocks have a good value as in bang for the buck. They do very well ported. Hughesengines offer a really nice CNC job.
What is your wallet thickness?
 
So my 340 seems to run out of steam right around 6700 rpm. Cam card states op range of 4500-7500 and my specs are 340 with 11.7-1 custom ross pistons forged, 302,309 duration .654/.655 lift solid roller comp cams cam, X heads with 2.02 valves, harland sharp 1.5 ratio rockers, super victor intake with a 750 berry grant carb on top. Any suggestions on the best heads i could run on this? seems to be what wipuld be holding it back the most
Do you have,an actual E.T.& trap speed,to start with? Was involved,with almost the same combination,was running 1170's-60's @ 117 at Famoso...Had well done Manning Brady x heads on it.The engine builder stated"Edelbrock heads ported,will be the same,as what you already have..." He got 280 -ish on well ported Eddy(remember,this is 1995...) The car picked up a tenth,that's it..(weight reduction,from steel to aluminum?...) .He ended up,with a Edelbrock street tunnel,& 600 double pumper,picked up 3 tenths....Went single four ,250 N20 plate.. ,after that,ended up in the 10.3-10.2 zone,around 125 trap speed...You need, more complete information
 
Do you have,an actual E.T.& trap speed,to start with? Was involved,with almost the same combination,was running 1170's-60's @ 117 at Famoso...Had well done Manning Brady x heads on it.The engine builder stated"Edelbrock heads ported,will be the same,as what you already have..." He got 280 -ish on well ported Eddy(remember,this is 1995...) The car picked up a tenth,that's it..(weight reduction,from steel to aluminum?...) .He ended up,with a Edelbrock street tunnel,& 600 double pumper,picked up 3 tenths....Went single four ,250 N20 plate.. ,after that,ended up in the 10.3-10.2 zone,around 125 trap speed...You need, more complete information

280CFM on what i assume were hand ported heads is pretty impressive actually. But I suspect that is the max limit for hand ported. Like someone mentinoed, Hughes cnc and wide mouth cnc can do huge numbers, 300+cfm starting at .500. If he put heads with that kind flow and a bigger carb. Yeah, that's a recipe for 600+ horse in my mind. Maybe even 650+ if the work is done right.
 
280CFM on what i assume were hand ported heads is pretty impressive actually. But I suspect that is the max limit for hand ported. Like someone mentinoed, Hughes cnc and wide mouth cnc can do huge numbers, 300+cfm starting at .500. If he put heads with that kind flow and a bigger carb. Yeah, that's a recipe for 600+ horse in my mind. Maybe even 650+ if the work is done right.
Actually,OU812/IMM Engines,got over 300 with a hand ported set,for a stroker build..,Car Craft,shown the pictures..they were NICE....(Ironically,..the member I sold my heads to,had Brian flow them..(IMM....)
 
280CFM on what i assume were hand ported heads is pretty impressive actually. But I suspect that is the max limit for hand ported. Like someone mentinoed, Hughes cnc and wide mouth cnc can do huge numbers, 300+cfm starting at .500. If he put heads with that kind flow and a bigger carb. Yeah, that's a recipe for 600+ horse in my mind. Maybe even 650+ if the work is done right.
Agreed,Lustle.. Just watching the intake path restrictions go away,the car just runs SO MUCH BETTER....
 
Best heads for WHAT?...How much Money you want to spend?

CNC Eddy heads can run fast....you have dome pistons they will not work with the close chamber eddy head...nor close chamber Indy heads...Hughes Big mouth will require new pistons...new rockers as they use an offset intake rocker....

again how much you want to spend...or can afford to spend...W8 makes big power....the New Eddy Victor head is available and it looks like it will run with the W8 head....but again...going to new a lot of new parts....

SB VICTOR ready for Dyno | Unlawfl's Race & Engine Tech | Moparts Forums

actually your best buy might be a set of open chamber w2 heads...wont have to change pistons...but going to new a lot of other new parts....
 
Actually,OU812/IMM Engines,got over 300 with a hand ported set,for a stroker build..,Car Craft,shown the pictures..they were NICE....(Ironically,..the member I sold my heads to,had Brian flow them..(IMM....)

Wow that is very impressive. And must have taken some seriously intense time and effort. Hughes standard CNC porting does 300 cfm. And we know how accurate CNC is. To reach the same level by hand take's a lot of talent, time and dedication.

Agreed,Lustle.. Just watching the intake path restrictions go away,the car just runs SO MUCH BETTER....

If his X head's aren't ported. Even porting to 260-270 CFM with that cam, he will pick up at least 50 horse. At least.

I'm looking at porting my head's this winter, aiming for 260-270 cfm around .550-.600 lift. And then going solid roller to match. And I'm HOPING to make 475 horse. EXPECTING minimum 450, coming from 400-420 I'm making now. So with how much more is into his combo. He can really only expect much better results from better heads with more porting.
 
Best heads for WHAT?...How much Money you want to spend?

CNC Eddy heads can run fast....you have dome pistons they will not work with the close chamber eddy head...nor close chamber Indy heads...Hughes Big mouth will require new pistons...new rockers as they use an offset intake rocker....

again how much you want to spend...or can afford to spend...W8 makes big power....the New Eddy Victor head is available and it looks like it will run with the W8 head....but again...going to new a lot of new parts....

SB VICTOR ready for Dyno | Unlawfl's Race & Engine Tech | Moparts Forums

actually your best buy might be a set of open chamber w2 heads...wont have to change pistons...but going to new a lot of other new parts....
Tony,I looked for a set,of decent Econo W2's,a decade ago... couldn't find a set,for the 408 build... Haven't seen an available set,for a decade...My favorite cylinder head,btw....
 
Wow that is very impressive. And must have taken some seriously intense time and effort. Hughes standard CNC porting does 300 cfm. And we know how accurate CNC is. To reach the same level by hand take's a lot of talent, time and dedication.

Agreed..He runs a 10.60 Duster,last I knew...

If his X head's aren't ported. Even porting to 260-270 CFM with that cam, he will pick up at least 50 horse. At least.

I'm looking at porting my head's this winter, aiming for 260-270 cfm around .550-.600 lift. And then going solid roller to match. And I'm HOPING to make 475 horse. EXPECTING minimum 450, coming from 400-420 I'm making now. So with how much more is into his combo. He can really only expect much better results from better heads with more porting.
You running a 340?..I would guess closer to 500....
 
There is a lot more to getting a car to run fast then peak flow and peak horsepower...Good thing there are quiet of few choices available today....as crackhead says...pick your parts and spend your money....

OP never specified what he wants out of the engine/car....best bang for the buck MIGHT a 4 inch crank....
 
There is a lot more to getting a car to run fast then peak flow and peak horsepower...Good thing there are quiet of few choices available today....as crackhead says...pick your parts and spend your money....

OP never specified what he wants out of the engine/car....best bang for the buck MIGHT a 4 inch crank....
That's a good look ,at another way to drop shift points,make it more reliable.....
 
Well for starters, your carburetor is too small, IMO.

That said, the "best" heads are relative to what you plan to do with the car. IQ52 would be a good one to chime in.

Might be a lot of effort to straighten this one out. Clues..... "Seems to run out", "cam card to 7,500". No other posts with any more information.
And I think you might understand what kind of king kong effort it would take to get an X head to flow to .650" lift. Not many guys on the planet can do that. Any head buy a competent porter would probably be better, once you know how the present heads flow.
 
as of current the car this 340 is in ran 12.27 at 112. it is a stock suspension car essentially and was going through the traps at too low of an rpm like 5900. RX302S-R6 is the camshaft and they have a ton of portwork done to the heads. my car is a 69 dart which we are building. it will have an all out tub job, frame rail work, 10 point cage, dana 60 with 31x16.5 dot slicks 5.38:1 gears, 4 speed with a scattershield and all that and a vertigate setup. also a cool fact about the dart is it is the number 1 dart off the line from L.A for 1969 sequence number 00001. factory radio delete car with the full trim piece on the dash and everything. turqoise with a white top
 
So the engine is making around 380-440 HP. I've seen a lot of X heads with a "ton" of port work that flow in the 245 cfm range and stall at .470" lift.

The best head? Certainly not the best, but the simplest thing to do would be go to a ported set of RaceMaster/ProComp or Edelbrock RPM heads so you can use all the other parts you already have. They'll make a big difference over what you have now. An OOTB set of Edelbrocks will flow about what most ported X heads will. Here are the results of one set of RPM heads we did for a .550" lift cam. There are others who can get similar results.

Lift............OOTB.........Ported
.100..........61/53........68/57
.200........126/107....140/124
.300........175/142....199/181
.400........223/157....242/218
.500........248/165....273/234
.550............N/A........283/240
.600........250/169....290/245
 
domed pistons custom ross pistons

11010295_1576413729268890_6452279918153953872_n.jpg
 
Oh dear. There will be a number on the bottom (top maybe?) of the piston. I would call Ross with that number and see what cylinder head that piston was designed for and what heads they may fit.
 
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