781 BBC Heads Question

[87Lowrider]

I picked up a 454 & TH400 combo this weekend out of a 1976 3/4 ton pickup. Casting on the block is 361959 and 336781 on the heads. In another thread someone said they were 781 heads, but I'm new to BBCs still so that's where I got the 781 number. I understand it's a good head though.

I haven't pulled the pan yet to inspect the the engine but it doesn't knock. We actually drove it into the garage to pull the drivetrain out. It's going in my '87 SWB pickup. This is my weekend cruiser until I get the '57 p/u ready for the road.

I don't want to stroke it yet and if I don't have to rebuild it, which I suspect I won't, short of a possible valve job, I'd like to add a thumpin' cam, intake and carb and go have some fun.

Does anyone have any suggestion for addons to this engine?

Kenny

[f.monroe]

Cam , intake , and headers . I had a stock 454 in my truck shortly after highschool . It didnt really impress me after 2nd gear . I switched to 3.73 gears , installed a Crane cam that if I remember correctly was 286/296 duration and 535/553 lift . I used a 650 double pumper then went to a 700 double pumper (man secondaries ) on an Edelbrock Torker oval port intake . The one that sets the carb at about a 20 degree angle . The truck pulled good to about 5700-6000 rpm , spun the tires in first or second when hammered , and sounded great . Nice mild motored bigblock that would get a little respect . 4.11 gears would have helped in high gear since it had 275/60's rear but I switched to 295/50's on Weld Draglites and picked the truck up a little in high gear . I had a set of M&H Racemasters on a 15 x 8.5 Centerline wheel that hooked really well on the street . It was a 13 second truck with the Racemasters and that wa good enough back then to keep up with most street cars . I know of one Super B that was surprised when we left a red light . Frank

[streetstar]

781 heads are oval port and can support up to, ....mmmm ..... maybe 600 hp naturally aspirated. Making this much power will require quite a bit of port massaging though

They came out in passenger car engines and are a pretty good head to build with.

Being an oval port design, most people feel they are better on the street than the strip, where a rectangular port head is better.

Stick to a mild cam and you will be happier unless the heads are really worked over. The 781 is a popular head, -- run 'em and enjoy them, but if you have to rebuild 'em and want to do ,more than a 3 angle valve job, , its almost just as well to go with some of the newer aluminum castings.

Great street head though. Performer RPM intake with a 650 double pumper would be torquey -- your cam choice would be dictated by your converter choice, the stall speed you want, etc. etc., so i won't even try to guess on that

[87Lowrider]

Thanks for the info... instead of reworking the stock 781s, I may just go with the alum RPM heads / intake / 650-750 carb and the COMP cams xtreme energy 552/286 cam that I've got sitting here waiting for a motor to put it into. But, I'm building a weekend cruiser, not a strip vehicle. Alot to take in on my first project.