Its up to you obviously,..but high rpm and blower and N20 apps are usually where you see such size headers,..there are thousands upon thousands of 572~58x BBC's making BIG power and running well into the 8s with 2.125 primaries,...I just would hate to spend that kind of money on maybe 10hp MAYBE,..20hp for a small window in the curve. That money could be much better spent elsewhere,..jmo what did the heads flow at .700?
The heads flowed 291 at .700. I have 3" exhaust with X pipe, 2" primary with 3" collectors, Ceramic coated. TA makes larger 2 1/8 and 2 1/4 primary tubes but for 68 up and race frame cars. I am HAPPY to stay with the 2" if you RACERS believe that will work fine. I didn't notice anything negative with that setup before. Only adding another .020 to the bore. Should be 4.560 to 4.580. The piston pin clip broke and scared the cylinder on #6.
If it was me I'd try just cutting and replacing the collector to 4 inch may be a happy medium at not an outrageous cost ..the bigger inches will like the bigger collector ...the 2 inch primary might be on the small side but the sp2 on the intake side is also too small IMO
291??,...you sure?? Because TE heads flow more than that out of the box With what you have now,. The 2in headers are more than fine,...if you have the funds to spend you need headwork,...with 580in you need 360cfm minimum to even come remotely close to using those cubic inches. What did the engine make on the stand or better yet what did run?
That intake is pretty much untouched from what I see,...they rolled the short turn over in corners but honestly that clover leaf design isn't that great jmo
Not real sure on the flow, May be from the ported original ones. What intake do you suggest, direct FI? I will look for dyno sheet, around 800 if I remember correctly.
Back when it was 573. Demon carb, different cam, stainless valves, copper head gaskets and lots of H2O/oil mixing.
The sp2 is a capable intake,...but only after substantial work,...most everyone make over 750 goes to the SPX retrofitted for the TE heads or a Mopar intake to get the flow needed to support 800+hp,...what compression you running?
A set of the 2.125 super comps are all you need,...if you had more comp and more intake I would say MAYBE,.. you would see a worthwhile gain with 2.250,...put some nice merge collectors on the TA super comps and you'll see a nice gain,..for around $2k time they are coated and everything,...you will need to do some frame clearance work and I would put a motor plate in it if it were me that free up alot of room down there
That is the weirdest dyno chart I've seen. Look at the massive fluctuations in horsepower between each 100 rpm increment.
Probably a land and sea dyno Jim Burek had one that come over with Noah i think,..it was the same way huge fluctuations and pretty liberal too
