Yes, and rotators on both intake and exhaust springs. All of that is fixable.
The ski-jump in the intake port is more difficult.
Right you are Travis.travis wrote: ↑Mon Dec 03, 2018 4:23 pmI think you need to replace a bunch of your 1’s with 2’s. 130, 155, and 160cc is stock sbf and smogger sbc territory.pdq67 wrote: ↑Mon Dec 03, 2018 4:09 pmCharlie,
Mark does a great -236 head, but I don't by any stretch think the intake ports are down around 195 to 200 cc's like stock PP heads vs the L-29's at say 130 to maybe 135 cc's or so IF I have this right, please check me here. Almost all stock large ovals are generally like 155 to may be 160 cc intake port sized..
I might still have OR had a mag article where they compared the new L-29, 454, P/U engines heads to the old 454 PP P/U engines heads and there was no comparison due to the 100 cc heart-shaped, fast-burn chambers of the L-29 head vs the something like 113 cc's or so standard chambered large oval head.
And I am NOT taking anything away from Mark because earlier John L. did a couple of tests (in two different mag articles), years ago using a 496 and later a 502 both starting out as lo-po, reworked PP headed, P/U engines turned Hi-PO with more cam and better reworked heads. One article is in the mag that has, "Chezoom", on the cover! CR stayed the same all through the tests. I want to say like 9.2 or 3 to 1 CR?? I want to say his 1st cam was a CC 252HE(??) for P/U or tow-truck engine use..
I bought my, "swap meet", -206's that should be down around 96.7 to 98 cc chamber size to play with using a stock mid '70's P/U 454 along with just .020" thick steel shim head gaskets to try to up their TERRIBLE about 7.9 to 8 to 1 CR so that a decent cam could be used to up Hp and T. I think if I remember right, I could get up to like 9.2 or 3 to 1 CR??? Therefore a cam like a CC 268HE, (218 @ .050), could be used vs a stock cam at like 198/198 @ .050 or so?? Sorry, I forget??
I never got any farther along than wishing on this project..
Don’t L29’s have a non adjustable valve train too?
A simple and easy combo I’ve done many times.scottcleaver wrote: ↑Mon Dec 03, 2018 12:01 amA little midnight contemplating. Rebuilding a 1990 454SS truck engine. *I will not be rebuilding it to its original 230hp version. I hope to build a 450-500 version. Given that the truck will need to be street friendly, adequate brake vacuum, run on crappy 87 octane gas and really just be a calm cruiser, I have compared two sets of factory heads as well as aluminum heads. For this comparison I want to stick to the factory steel head options due to price. A set of 049 heads versus the vortec L29 heads. I will get the correct piston for whichever head i choose as I don't want to be over 9.0 to 1 compression. I know there will be a ton of additional variables like cam, intake, headers, gearing, converter and others but I really want to just talk about the heads. Which head would you go with if it was made available to you?