SBC manifolds, In & Ex

Adger Smith · 02-28-2013, 10:07 PM

Well, the rules spell out no Brzezinski. so my customer and I are not going there. We know the casting numbers don't matter, but someone out there knows what numbers are better than others. My customer is always looked at because he has always understood how to use the power he has and make the car handle. We have been doing this for a long time as engine builder/customer. We have won track championships without cheating, but we do bend rules. This 4412 carb Deal is something new for us & most of the other guys. The car will weigh around 3200 lbs. I've already put atogether a mule and had it on the dyno. It came in a little low (RPM) on power, but had a great power curve. It looks like I had a little too much intake duration and the ex flow was not too good. He has small log manifolds.(only legal ex manifold) I also had a trick valve angle on the ex that might not be working on overlap. When I do the "Good engine" we wanted to try other parts. These are just what we had in the used parts bin, except the cam. We have a 14" vac @ 1200 and a .447 lift rule Hyd cam. cast flat tops and 4 equal valve reliefs. Stock 1.5 ratio rockers. Stock pushrods (5/16) and any open chamber heads. No porting on heads or intake or ex. Not sure if the late mod alum manifolds are legal. it's not in print if they are. Well, as usual any help or constructive comments will be appreciated.
Thanks,
Adg

02-28-2013, 10:07 PM	#5
Adger Smith VIP Member Join Date: Dec 2001 Location: Texarkana Ark/TX Posts: 2,446 Likes: 575 Liked 880 Times in 311 Posts	Re: SBC manifolds, In & Ex Well, the rules spell out no Brzezinski. so my customer and I are not going there. We know the casting numbers don't matter, but someone out there knows what numbers are better than others. My customer is always looked at because he has always understood how to use the power he has and make the car handle. We have been doing this for a long time as engine builder/customer. We have won track championships without cheating, but we do bend rules. This 4412 carb Deal is something new for us & most of the other guys. The car will weigh around 3200 lbs. I've already put atogether a mule and had it on the dyno. It came in a little low (RPM) on power, but had a great power curve. It looks like I had a little too much intake duration and the ex flow was not too good. He has small log manifolds.(only legal ex manifold) I also had a trick valve angle on the ex that might not be working on overlap. When I do the "Good engine" we wanted to try other parts. These are just what we had in the used parts bin, except the cam. We have a 14" vac @ 1200 and a .447 lift rule Hyd cam. cast flat tops and 4 equal valve reliefs. Stock 1.5 ratio rockers. Stock pushrods (5/16) and any open chamber heads. No porting on heads or intake or ex. Not sure if the late mod alum manifolds are legal. it's not in print if they are. Well, as usual any help or constructive comments will be appreciated. Thanks, Adg __________________ Adger Smith (Former SS)