360 small block help

Posted By: 1swingin

360 small block help - 08/14/10 01:55 PM

Goodday,
Iam in the process of putting together a street/strip 360 for my demon. This is my first small block and iam pretty much clueless. Ive owned b/rbs my whole life so its gonna be an adventure. I pulled a 35k 360 fron a 1985 d350 that runs exellent. Iam not trying to make 500 h.p. just something to push my 3200 lb a body into the high 12s low 13s without to much trouble. I really dont wanna tear into the short block but iam sure the comp. ratio sucks so I may have to. I figure 350 to 400 h.p should get me close to where I want to be. So what heads,cam,intake would you use? I have two 318 magnums laying around so if the heads on that would help I got them. Any suggestions would be appreciated. Thanks for your time.

Posted By: 540challenger

Re: 360 small block help - 08/14/10 02:05 PM

Quote:

Goodday,
Iam in the process of putting together a street/strip 360 for my demon. This is my first small block and iam pretty much clueless. Ive owned b/rbs my whole life so its gonna be an adventure. I pulled a 35k 360 fron a 1985 d350 that runs exellent. Iam not trying to make 500 h.p. just something to push my 3200 lb a body into the high 12s low 13s without to much trouble. I really dont wanna tear into the short block but iam sure the comp. ratio sucks so I may have to. I figure 350 to 400 h.p should get me close to where I want to be. So what heads,cam,intake would you use? I have two 318 magnums laying around so if the heads on that would help I got them. Any suggestions would be appreciated. Thanks for your time.

The heads and the rockers of the magnum would be a great choice actually the best IMO "in terms of stock heads" RPM air gap intake.headers and a nice came some where around 233 @.050 and .485 lift. Try to get the thinnest head gasket to bump compression I think there used to be a .028 but it is hard to find. Keep in mind the magnum rockers are 1.6 ratio when choosing a cam. Also you might want to get the guides cut down.

Posted By: 1swingin

Re: 360 small block help - 08/14/10 02:14 PM

Thanks! When swapping on the magnum heads,which pushrods should I use? I remember reading somewhere that the magnum heads are oiled diferently than the old school la heads. I also remember they respond well to port work. Iam no porter by any means but iam capable of some minor gasket matching and cleaning up the bowls. Is it worth the aggravation? Or just bolt them on and gas it!!!!!!!! Thanks again!

Posted By: MR_P_BODY

Re: 360 small block help - 08/14/10 02:24 PM

Quote:

Thanks! When swapping on the magnum heads,which pushrods should I use? I remember reading somewhere that the magnum heads are oiled diferently than the old school la heads. I also remember they respond well to port work. Iam no porter by any means but iam capable of some minor gasket matching and cleaning up the bowls. Is it worth the aggravation? Or just bolt them on and gas it!!!!!!!! Thanks again!

Use pushrod oiling and the best bang for the heads
is to do the bowls and just clean the runners

Posted By: 1swingin

Re: 360 small block help - 08/14/10 02:36 PM

Thanks! Lots of good information! How about decking the heads? Nothing to crazy but how much should I shave off to help comp. without screwing up valve train geometry. I realize I will have to have the intake done to. Thanks again!!!!!!!!!!

Posted By: MR_P_BODY

Re: 360 small block help - 08/14/10 02:44 PM

That would depend on how much you want to raise it
but the thin head gaskets might do what you want...
you need to sit down and think out your out come and
budget... but if you go with the magnum heads you might
want to have them trued up anyways so that would be
the time to do any compression changes

Posted By: 1swingin

Re: 360 small block help - 08/14/10 02:49 PM

Good Idea. I think just a small shave to true them up would be good. Iam trying to be budget minded. Iam putting together a 470 low deck and I would rather dump the money in that then to have a couple grand in a temperary engine. Thanks alot for your help! Nice car!!!!!!

Posted By: emarine01

Re: 360 small block help - 08/14/10 03:12 PM

If your plans are to build a big engine i would just put a 125hp plate system on it, and have fun

Posted By: HotRodDave

Re: 360 small block help - 08/14/10 04:06 PM

I have a vey similar build to what you are thinking about, it is a NAPA style rebuilt 72 360 .030 over bore with stock type very low compression pistons. I stuck in a comp XE268 I had lying around, mopar .028 head gaskets did a light port job on the heads, stuck an M1 single plane on it and I already had TTI headers on the car then I stuck a 750 carter competition AFB on it and it is very quick even with my 2.76 gears. I think a better cam with the low compression would have no more intake duration and little less ex duration, I think a comp 270 magnum would be perfect. I am useing the GM 3100 V6 springs, if you do that check VERY carefully to make sure you are not in coil bind, the 270 magnum has a slightly shorter ex lift so you should be fine but check anyhow. Even with the 2.76 gears and 225-50-17 tires I found out mine will pull to 6000 rpm even in high gear with enough road