GMC project: engine content. Warning, much bench racing ahead

BeardedJag wrote: So is a carb swapped 5.3 with 243 heads and MS3/4 cam out of the question? Should get you your HP mark. And can find all of it used. I know you said something about not liking how they look in one of your pics you posted, but that can be fixed.

We discussed that a number of times here and we came back with the idea of the 'big block look' on a gen III/IV engine would work fine. I'd obviously prefer a 6.0 or 5.7, but the 5.3 would work too.

The MDS/edelbrock combo is uncheap, but it's less money than rebuild parts and gets me a much better engine if I can swing a cam swap for that gen III/IV engine.

I took some advice and checked craigslist for used engines, and gosh, there are lots of rebuilt small blocks, but who actually knows what's inside, what the oil pressure was, etc. It would take some good trust. It's still a possibility though. I think the right way to buy a used engine is if the hood is warm when you hand over the cash and get the hoist.

How about an LT1? Optispark woes can be fixed, flush out the Dexcool and burn it, and they're pretty decent little engines, underappreciated, too. You can buy running cars with LT1's for LeMons money, which nets you basically a free engine. I don't know exactly how to carb it, But I can't imagine it's unpossible, and quite probably very not hard.

Edit: I understand they are also called "Gen II". not sure if that was suggested yet or not.

volvoclearinghouse wrote: How about an LT1? Optispark woes can be fixed, flush out the Dexcool and burn it, and they're pretty decent little engines, underappreciated, too. You can buy running cars with LT1's for LeMons money, which nets you basically a free engine. I don't know exactly how to carb it, But I can't imagine it's unpossible, and quite probably very not hard. Edit: I understand they are also called "Gen II". not sure if that was suggested yet or not.

LT1 carburetor intake

Something like this: http://baltimore.craigslist.org/cto/4811065711.html

Redo the head gasket, and the wheels alone are worth something stupid like 300-400.

In reply to volvoclearinghouse:

Assuming his is a five bolt, I'd put those wheels on Tuna's truck.

I've thought one of these cars with the 5.7 LT1 would be an excellent drivetrain donor for a number of swaps. Shift kits are cheap and everything is there to make the swap happen. Trans may be due for a rebuild but that's not crazy expensive either.

fyi, the ls motors are known to just last waaaaaaaay longer.

guys are reaching 200k miles opening the motor to have it look like new in the cyclinders. (scoring still visible etc.)

find an alluminum block 5.3 should drop quite a bit of weight off the nose of the truck and have ~330 ish hp...

LFA or Lz1 designation.

from what I recall an ls6 intake alone should help push it up higher as would an ls6 head swap (243 casting.)

should be available from a junkyard for 500-600 bucks from what I recall... teh wiring/ecu and gas pedal should be included or be a bit over that. say 800 bucks...

Build a 377 de-stroker

400sbc block + 350sbc crank + 3000-7500rpm range circle track cam & valvetrain to match + 202/160 heads + good short ram intake/carb(s) of choice. Budget build for a 350+hp high revving sbc right there. Because it would be a de-stroker, the damn thing will last forever too.

Bonus points for originality if you use the Offenhauser 6x2 intake.....

FWIW, when I was in high school, some friends and I built a budget 383 stroker and then a budget 377 destroker out of the plethora of sbc parts we had laying around. The 383 blew at the drag strip for some stupid reason, but the 377 went into the same car and ran quicker times and never blew up. That engine is now in another friend's dirt track car....the same unopened build 11 years later. Not bad for being built using mostly used parts in a barn with a dirt floor.

In reply to yamaha:

Uhh, ok. I should get my goals with 350 cubes. If I can't, it's cheaper to start with 400 cubes. I don't get the mix and match stuff unless you're trying to hit some class cubic inch limit. There is a virgin 400 engine for $700 on my local craigslist right now that I would jump at before spending money on rods and crank to get something with less cubes.

In reply to tuna55: [takes deep breath to scream]

CUBIC INCHES OF DISPLACEMENT MEANS ABSOLUTELY NOTHING IN RELATION TO YOUR DESIRED POWER LEVELS

[/screaming]

For gods sake, you could build a 283cid that could make the power levels you are looking for.

The mix & match I mentioned is easily built for cheap thanks to morons building the "Allmighty to rednecks everywhere" 383 stroker. E36 M3, people around here used to throw away 350 cranks and 400 4bolt blocks.

In reply to yamaha:

You're wrong, but I love you anyway. I'll build a 400 before a 377 or 383

In reply to tuna55:

So long as you don't go with a gen III/IV like every other lemming.

There something appealing to me about a 377 screamer and a close ratio manual. Kinda like a high performance version of the old GMC short stroke V6 engines with two more cylinders.

I do not, and will not (without data) believe that short stroke engines, when supported by cylinder heads befitting the displacement, produce a more favorable horsepower curve, even at higher RPM, than their higher displacement, longer stroke brethren.

yamaha wrote: In reply to tuna55: So long as you don't go with a gen III/IV like every other lemming.

Oh yeah, because the 350 in there now is sooo unique.

I was wondering how long this would go on before tuna went off with his anti-short stroke rant.

And, to Yamaha, yes, cubic inch of displacement does mean something to your desired power levels. Fewer cubic inches generally means more money spent to get your desired power levels. A 350 will make the same power as a 283 at a lower RPM and for less cash invested. That said, the % difference in cubic inches between a 377, a 383, and a 400 is almost negligible. I'd go with the cheapest option- and if that involved a cheap 400 block and a cheap 350 crank, I'd be curious. At least then you could say, "I've got a 377" and a bunch of people who thought they knew SBC would go "wha??"

Of course, if you have a 400 block, you likely also have a 400 crank, at which point...well, why wouldn't you just build a stinkin' 400?

In reply to tuna55:

They don't, but they're more fun than something that's all in by 5000 rpm, and you can probably put together a 377 from unloved, discarded parts cheaper than buying a complete 400 core.

volvoclearinghouse wrote: I was wondering how long this would go on before tuna went off with his anti-short stroke rant.

I feel all tingly now

Kenny_McCormic wrote: In reply to tuna55: They don't, but they're more fun than something that's all in by 5000 rpm, and you can probably put together a 377 from unloved, discarded parts cheaper than buying a complete 400 core.

OK, I suppose if I happen to see a 350 crank or a 400 block on the side of the road, I'll pick one up. Otherwise, I'd rather build the 400.

pres589 wrote: DIYMatt or someone did an LS swap into a similar truck, I think, and used Camaro manifolds or some such parts. There's a build thread on it. A 4.8 + LS6 cam would be within your acceptable HP range, I believe, and be cheap. Would need to get it tuned on a dyno once it's all together. Obviously a 5.3 would be even more acceptable but would probably cost a bit more.

2010-up Camaro manifolds. I had set the engine mounts back to allow for using a low mount A/C compressor (which isn't even on the truck right now, but I could add it later) and this required modifying the engine stands, but with the engine stands in the stock V8 location they'd fit with no issues.

MadScientistMatt wrote:

pres589 wrote: DIYMatt or someone did an LS swap into a similar truck, I think, and used Camaro manifolds or some such parts. There's a build thread on it. A 4.8 + LS6 cam would be within your acceptable HP range, I believe, and be cheap. Would need to get it tuned on a dyno once it's all together. Obviously a 5.3 would be even more acceptable but would probably cost a bit more.

2010-up Camaro manifolds. I had set the engine mounts back to allow for using a low mount A/C compressor (which isn't even on the truck right now, but I could add it later) and this required modifying the engine stands, but with the engine stands in the stock V8 location they'd fit with no issues.

Sweet thanks, and those manifolds probably flow better than the headers for the 350 which I could actually afford.

In reply to tuna55:

If you think a Caddy 500 is going to look "off" under the hood of your truck, an LS with a carb and whatever is going to look even weirder. Like the kits that use a 302 dizzy and what not.

Can I change my answer from 4.8/LS6 cam combo? I now suggest a late Olds 403 (not the early revy one, the older longer stroke job) with a mild port job backed by a T56. Or a 200R4 if you're not into the whole self-shift thing.

pres589 wrote: In reply to tuna55: If you think a Caddy 500 is going to look "off" under the hood of your truck, an LS with a carb and whatever is going to look even weirder. Like the kits that use a 302 dizzy and what not. Can I change my answer from 4.8/LS6 cam combo? I now suggest a late Olds 403 (not the early revy one, the older longer stroke job) with a mild port job backed by a T56. Or a 200R4 if you're not into the whole self-shift thing.

Did you see the 'big blog look' pictures? If you took off the fuel rail you'd have a hard time seeing he difference.

No to the caddy, no to the 403. I am not looking for a swap just for a swap. Neither of those engines are going to offer anything (other than cubic inches) over the 350 I have now.

I already have a transmission and intend to keep it. It's a MY6 optioned chevy 1-2-3-OD, call it the A833 for familiarity, but it's really an NP440.

In reply to volvoclearinghouse:

My post was towards his power goals of 350-400HP. Any SBC from 283-400 can accomplish that goal. I only start with 283 because I lack experience with the 265cu sbc.

And Kenny has the right feeling....this is grassroots motorsports, not pocketbook emptying motorsports. Also note, 377 in the 7k rpm range sounds pretty awesome.