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

You have been warned!

So many of you (I have a surprising amount of readers, somehow) have already seen this, but I wanted to get a broad opinion of a "way out in left field" idea. In the short term, the engine will get freshened in some way and reinstalled. Off in left field that it's actually in another field altogether. You know that tee-shot where you put it right in the middle of the fairway of #12, but you're on #9? Sort of like that.

I have a number of goals, in a far off make-believe galaxy we can only hypothesize might exist. Let's say 300-400hp, silly cheap, tractable and reliable. The thing I was also trying for was 'stock appearing' or at least period correct.

For the record, here is what the stock engine bay looks like:

I dig the look. It's functional, attractive, and has purpose. I may modify the fan box, and mine isn't a boosted brake setup, but you get the idea.

I cannot stand the look of the gen III/IV engines in there because the usually look like this:

And, me, even as aesthetically dumb as I am, understand that I cannot have this in a restoration project. Now, if the ante is upped, they can look "ok".

And I would have no issue running a carb on the gen III. Please don't yell at me for that.

But then I saw another thread today and remembered this.

The trucks could be ordered with an I6, and they were fine. Honestly the look of the original I6s was not spectacular:

But I suspect that a modern 4200 Vortec would be a neat swap, get my power goals, and be modern to boot.

The estimated cost for the Tuna 350 is between $2K and $3K depending on what I want and how much stuff used I find.

I have no idea at all how to budget for modern engine swaps. I do know that it would make me mad to have to redo my fuel tank and lines again, but I'll probably have to accept that the 4200 is not going to have an easy button for carburation.

So enjoy my rambling and pictures. Offer (constructive) thoughts if you have them. Please, no "controlled fuel leak" stories about the infinite superiority of fuel injection. I honestly could not care less about that, it;s more "how cheap can this be done to meet my goals"

Do an original Inline six.. Carb'd with offy parts.. That'd be cool.

see http://inliners.org/

LS+carb/TBI/make your own classic air cleaner+big block look coil covers:

I believe that the best 4200 engines did ~300HP at the flywheel, so 400HP will take a fair amount of work and money. If you can hit those power goals by rebuilding what you have for $2-3k I would do that.

Junkyard_Dog wrote: LS+carb/TBI/make your own classic air cleaner+big block look coil covers:

seriously, the big block valve covers combines with the even spaced exhaust tubes makes a perfect fit.

Good call!

Big block look, Aluminum, Insanely expensive billet.

Looking at the middle picture, you might be able to re-purpose your original covers for the look you want.

How the heck are you spending 2 to 3K for a rebuild on an SBC?

http://www.summitracing.com/parts/nal-12499529/overview/

almost 300 hp right outta the box. Brand New.

Under your budget and probably at the bottom of your HP goals, how about an L31 Vortec truck engine + carb/carb manifold + cam + headers. If you keep the cam modest ("RV" cam?) you may not need to even modify the heads.

I know this is GRM and we all like to talk about crazy swaps, but this is cheap and bolt-in simple.

wvumtnbkr wrote: How the heck are you spending 2 to 3K for a rebuild on an SBC? http://www.summitracing.com/parts/nal-12499529/overview/ almost 300 hp right outta the box. Brand New.

Because I am a slippery-slope kind of guy with this truck. If I take it apart, it's gotta have... and the list gets pretty big. Sure, I can get pistons and a rering kit and an el cheapo cam and lifter set, maybe an intake, done for around $1,500, but if I'm there already, I ought to do the oil pump, water pump, rockers, pushrods, heads, blah blah blah...

I pretty much know I can get a LQ9 or LQ4 for several hundreds of dolalrs with a few decades less wear, drop on the MSD/edelbrock carb thing and get running for less than my ideal, and maybe even with the el cheapo, but I get (way better) aluminum heads, roller cam, better valvetrain, stronger rotating assembly etc right off the bat without touching anything.

That's awfully appealing now.

SEADave wrote: Under your budget and probably at the bottom of your HP goals, how about an L31 Vortec truck engine + carb/carb manifold + cam + headers. If you keep the cam modest ("RV" cam?) you may not need to even modify the heads. I know this is GRM and we all like to talk about crazy swaps, but this is cheap and bolt-in simple.

I have considered those, but the deal is that they don't have a huge amount to offer over the engine I have now (roller cam, better heads) but they do probably have enough wear to politely request a rebuild. And those ugly ass centerbolt valve covers.

In reply to Junkyard_Dog:

The big block look is better since the exhaust pipes are evenly spaced. It hides well under there and I love the "376" emblem on the air cleaner

http://greenville.craigslist.org/pts/4813799238.html ????????????

In reply to Fueled by Caffeine:

Yeah, something like that.

tuna55 wrote: In reply to Fueled by Caffeine: Yeah, something like that.

I approve of this project. Hats off to you sir.

I really like the idea of an inline 6, but that engine is quite long compared to an SBC.

aw

He was all set to buy an inliner and you guys ruined him!

(but I seriously dig that LS with the big-block looking valve covers)

gearheadE30 wrote: I really like the idea of an inline 6, but that engine is quite long compared to an SBC.

Well the trucks came stock with I6s from the factory with the engine moved back, so it's reasonable to assume the 4200 would fit in much the same way.

Hungary Bill wrote: aw He was all set to buy an inliner and you guys ruined him! (but I seriously dig that LS with the big-block looking valve covers)

Dude, I am with you on both counts, but it sure does look the part, right?

If you want ~350hp "silly cheap" and want it to look like a late 60s Chevy V8, the only real option is a gen 1 SBC.

tuna55 wrote:

Hungary Bill wrote: aw He was all set to buy an inliner and you guys ruined him! (but I seriously dig that LS with the big-block looking valve covers)

Dude, I am with you on both counts, but it sure does look the part, right?

seriously! That is SHARP!

Ok, but like Kenny said. The legacy SBC makes 350hp pretty easy. Maybe some junkyard vortec heads and a mild cam.

I hear ya about the project creep though. It's hard not to "take care of stuff" while you're in there, but remember: If you buy the LS, you're going to open it up and you're going to have to fight the same project creep with a $1500+ engine.

Hungary Bill wrote:

tuna55 wrote:

Hungary Bill wrote: aw He was all set to buy an inliner and you guys ruined him! (but I seriously dig that LS with the big-block looking valve covers)

Dude, I am with you on both counts, but it sure does look the part, right?

seriously! That is SHARP! Ok, but like Kenny said. The legacy SBC makes 350hp pretty easy. Maybe some junkyard vortec heads and a mild cam. I hear ya about the project creep though. It's hard not to "take care of stuff" while you're in there, but remember: If you buy the LS, you're going to open it up and you're going to have to fight the same project creep with a $1500+ engine.

Goal is that the gen III would get a cam. If I was feeling really ambitious, maybe headers.

That's it.

I get it, though.

throw a Dirtymax in there and be done with it.. it will be cluttered and it's a heavy engine, but 650 torques compensates very well for that.. and the hood is closed 99% of the time, anyways..

Keep in mind with an LSx you are looking at a bit of $$$ for headers or doing an ugly plasma cutter hack job on your frame to get the exhaust to fit.

What about adding an old school engine, but building your own TBI or multiport setup to hide under the stock looking stuff. You like a challenge.

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.