Al. Hell, if you get me your heads by the time I trailer my car down, I'll drop them off for you no charge.

 

Al, Fox Lake, and xr8ted

 

would the B heads flow just as well as 03 heads once ported? I found a set for pretty cheap and didnt want to waste my money.

 

would the B heads flow just as well as 03 heads once ported? I found a set for pretty cheap and didnt want to waste my money.

B heads usually flow more on the intake side (stock for stock, or ported for ported) than 03/04s. The later heads flow much better on the exhaust side due to their much larger exhaust port.
If you have a tumble port head, stick with it. You will make more avg./usable power than with B heads all else being equal.
Bs require completely different intakes than other tumble port heads, so don't forget to factor that into your equation as well.
If you're someday going with forced induction, you can stick with Bs. However, if you plan on making your power N/A or with spray, go tumble port no questions asked.

 

I don't plan on using a blower but who knows. I guess I'll keep shopping for some 03 heads. Thanks for the info

 

Fox Lake

 

B heads Mite flow better on the intake, but peak flow number's are not everything, for one the valve spends the least time open at max lift..There are many other factors in a cylinder head that can make them better then the other. Like volume yeah the b heads may flow alot of cfm but what is the port volume compared to the other heads what is the intake to exhaust ratio what has a better air fuel mixture. I think swirl port heads belong on chevy's...

Hands down Al. Pappito has put together some of the best heads and motors together.He has probably more wins and records under hbelt then any other.. So he gets my vote.. I just got a job @ R.M.I all they do is is cylinder heads so I hope in a few years some of you can break some record's using XRATED'S ****..

 

I cant post pics . I have some pics of a ford prototype intake that possibly reflects the actual optimised calculated requirements for the smaller primary and the much larger secondary. I am under the current impression that leaving the secondary port alone casting flash etc. And only working on the primary. If someone calculated the famous huge port volume and actually subtracted (the primary area the beginning entrance ) it may be possible that the funnel venturi area for the primary may account for a significant volume differential between years of heads. It seems now obvious to me that the primary and secondary flow different ammounts. B heads = econmy with mega potential. Cobra intake the knife edge in the upper is an attempt imho to equalise flow. I think an intake port job could be done on the primary remove intake inject apply create devise the (appropriate barrier) to seal valve area preventing metal intrusion to combustion chamber valve area. As an example if someone had the right bit tapered of course and had it set to the correct depth and prevented particulate intrusion yet enhacing flow to the constricted primary. What about the smaller exhaust exit ports for b heads ? Someone could say these are expanding gasses lets allow them to expell at a higher velocity and improve the pulsed scavenging affect? This is imho ready to be corrected lacking data etc. Intake design im up for that from scratch the heads need to done first.

 

If you're handy with a welder or epoxy you could always try fixing the problem all together. Though you would still have to deal with less than optimized A/F mixing.
The exhaust ports on a B head are the same size as those found on the 99/01 Cs btw.

 

Not worth the effort IMO...03 head casting are light years ahead of b heads IMO..If you are building a 8 sec high boost high rev motor thats another story...Short side raduis is not good on these heads infact there is none it is just a step. Air fuel mixture is not as good as the newer tumble port design...Remember you are only filling 281 cubic inches not a bbc motor. In the next few months we are gonna be doing some extensive R&d on all modular 4v heads so I will have some very nice results soon..I was hoping to have my 03 flowed by now but that is gonna have to wait until we weld up the chambers..

 

Andy, N/A wise, which are better, 03's or 01 C heads? What if they were both ported extensively?

 

Andy, N/A wise, which are better, 03's or 01 C heads? What if they were both ported extensively?

03s/FR500s/C in that order, but the first two are just about equal. The FR500s seem to have better casting quality, but the 03s have a monstrous exhaust port by comparison. After porting it's the same story. FR500s have a dry exhaust divider for N/A apps, and 03/04s have a wet divider for blown apps.
Send me a PM with your email addy.

 

The fr500 have smaller intake ports I belive...