okay big block guys,i got some questions for you

[pdeville96]

hey all,
picked up a 454 from a guy real cheap and trying to decide what to do with it and need some guidance, ive built small blocks but never gotten into a big block at all

so here it is 77 454 out or a motor home, has 781 heads, dont know much more since i haveant pulled it apart yet

im planning on putting this in and s10 pickup just to make a mean little street truck, i know want to stick with a stock rotating assembly but i want to bump up the compression while being able to run say 91 (since that is the highest i can get around here), ive read that flat tops and 781 heads only gets you to about 8.5:1.... so how big of a dome would i want to go to get maybe 9.5:1 or maybe 10:1? Everyone says to go bigger valves with the 781s, but is it really necessary if im trying to get say 450 hp? maybe just a good port and polish? or just freshen them up and run em? i also heard a comp xe274h cam works good with a set up like this? i would like to keep it a flat tappet cam... if possible, Thanks in advance guys!!

[Hollow65]

Check out Chevelle tech. Lots of 781 headed beast making serious torque and hp on 10:1 pump gas friendly. Best of luck

[BigDan3131]

I wouldn't bother building such a low hp engine like that for an S10. You would be better off doing a small block instead. Just based on the weight factor of an iron headed BBC, if you prefer a carb type setup stuff a 6.0L lsx engine in it with a 750 and you pretty much will get what your after besides the weight savings.

[pdeville96]

BigDan3131 i get what your saying, but its just more the fun of it, and i figure its easy to get that power out of a big block than stick a bunch into a small block, everything else is easy to fab up and stick into the truck

[prostreetC-10]

I tend to agree with Dan. Probably hard to sway you if you already have the BBC. It will make the truck super nose heavy and serious fitment issues. BBC like that are more easy torque than easy HP. All depends on your pocket book. Man what you could do with a 350ish motor that pulls to 7K. If you've every been in a mini truck like that that never hooks up because of the weight spread and HP......it gets old fast.

[GASoline71]

Originally Posted by pdeville96

BigDan3131 i get what your saying, but its just more the fun of it, and i figure its easy to get that power out of a big block than stick a bunch into a small block, everything else is easy to fab up and stick into the truck

BBC parts are more expensive... so you will probably spend just as much.

SBC = less weight up front...

S10 = EZPZ burnouts (no weight out back... so no need for BBC)

SBC + S10 = A lot of fun for way cheaper!

I know the coolness factor of a BBC is appealing... but I lean towards a SBC...

Gary

[b454rat]

I love it when everyone says big blocks are so expensive to rebuild. Yes there more than a small block, but everyone does/done that. No one seems to do big blocks anymore. I have about $3k into my 454 in my car. Nothing crazy, pretty much what OP has. I can't remember what pistons I used. Think they have .133" dome, so with the 781 about 10:1 compression. My motor makes about 375, and hauls some serious ass. Car weighs aboot 3200 I'm guessing. A very, very competent engine builder told me that you could put a flower pot in a cylinder of a big block and still make power. And yes a big block weighs more than a small block, but put an aluminum intake and water pump and it will lighten it some. If your building a street truck, put the battery in the bed to help lighten it. Also do a google for big block S-10, it's doable but quite a bit of work.

[prostreetC-10]

Originally Posted by b454rat

No one seems to do big blocks anymore.

I don't know if I'd go quite that far! As a matter of fact, I don't think I'd own one of these trucks without a BBC. Keep in mind that I am poor. I think the flat top pistoned 454 with 049 or 781 heads is one of the best bangs for the buck in these truck. Not so much because of the HP but the torque! You start with a decent block/heads, get it to breathe with headers/intake and throw a 270ish cam in the hole.......lots of fun on the cheap. It just seems like you would have a fight on your hands with both width AND length trying to get one in there. I know it's been done many times but it's like putting a BBC in a '32.

pdeville......as so many times, you pocketbook will dictate a lot of what you are asking for. Personally, I don't think I would build another flat tappet motor. I have bought a couple of sets of used retro roller lifters and roller tip rockers and had fantastic luck. It's one area I won't skimp on.

[snj8198]

Welcome to the forum pdevil96. And welcome back prosteetc10.

[CST10]

Originally Posted by prostreetC-10

I don't know if I'd go quite that far! As a matter of fact, I don't think I'd own one of these trucks without a BBC. Keep in mind that I am poor. I think the flat top pistoned 454 with 049 or 781 heads is one of the best bangs for the buck in these truck. Not so much because of the HP but the torque! You start with a decent block/heads, get it to breathe with headers/intake and throw a 270ish cam in the hole.......lots of fun on the cheap. It just seems like you would have a fight on your hands with both width AND length trying to get one in there. I know it's been done many times but it's like putting a BBC in a '32.

pdeville......as so many times, you pocketbook will dictate a lot of what you are asking for. Personally, I don't think I would build another flat tappet motor. I have bought a couple of sets of used retro roller lifters and roller tip rockers and had fantastic luck. It's one area I won't skimp on.

Gunna have to agree here. I have a 454 bored .040" over, flat top Pistons, 049 heads with minor port/polish, rpm performer intake, Holley 770 carb, stock bottom end, with a comp XM270HR cam and roller rockers. Put out on the dyno 487 TQ/436HP at flywheel all below 5000 rpms. It will roast the tires far faster than you think.

I love BBC engines, everybody's got SBC and LS engines. Mine stands out in the crowd even though there are those others faster.

[b454rat]

I think I forgot to mention it cost bout $3k to build my motor. This included all machining, cleaning, blah blah, balancing and assembly. Done SB, can't beat the torque/power of a big block. Honestly don't have much experience with LS, but slap a hair dryer on it, and whole new ball game....big block or go home!!!!!!

[BigDan3131]

Remember though he wants to put it in an S10 not a full sized car or truck. I'm building a BBC right now for my 65 and tons of us have them but in bigger vehicles. Even just adding the aluminum headed engine there will still be a 500 pound weight difference front to rear. To help me with that I plan to build a 32 gallon tank add two batteries and a 4"x6" bumper made from .250 wall steel to help offset the difference.

[Hollow65]

My brother did a sbc s-10. Fiberglass front end and about 400hp. That thing was a beast