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Am I crazy? Engine decisions...

ya your right the ss is 345hp and 380tq and you will need your wallet
yes the 400 sbc is known for overheating, the trick is to take a 1/2" drill bit and over size all of the water passages in the head gaskets
 
Don't wanna be a jerk and Hijack the thread but I'm in between a 6.2l diesel or a tbi350 in a 88 burban both are good deals...I'll be doing no bigger than 33's and building it for expeditioning. Naturally I've been following this thread that 383 option sounds like a winner for my 2cents in staying on topic cost+economy+torque+cost of gas vs. cost of diesel
 
jamacee said:
Don't wanna be a jerk and Hijack the thread but I'm in between a 6.2l diesel or a tbi350 in a 88 burban both are good deals...I'll be doing no bigger than 33's and building it for expeditioning. Naturally I've been following this thread that 383 option sounds like a winner for my 2cents in staying on topic cost+economy+torque+cost of gas vs. cost of diesel
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No worries about hi-jacking... :D We're all here to consolidate thoughts and experiences and learn from one another. Its all good!

So far... I am surmising that a EFI (or TBI) 383 might be my ticket. I still haven't convinced myself that a stock TBI unit could adequately feed a 383 making decent power numbers. :thinking: And on-the-fly tuning isn't available either. Which probably doesn't matter to some. But again... I'm trying to sqeeze out the "biggest bang for the buck!" (pun intended) :haha:

The diesel swap sounds cool. Certainly, the low end torque of a diesel would be the ticket! But I'm a little apprehensive on how well the swap would go. Having a lot of cheap, little conversion items on a list complete the swap is one thing... Switching to a different FUEL (less refined fuel) source, I would think one would need to change fuel tanks, fuel lines, buy a special fuel pump... etc. Maybe that is not the case?... :confused: I have never seen or read of such a swap with a truck like mine. It is foreign terrority to me. I do like diesels though. They are simple animals that are very efficient. Much more than a gas engine.

The 400 SBC sounds cool. Its right in between a 350 and a 454. Except I'd be afraid of minor, annoying differences between it and a 350 when I go to the store to buy parts for it. 400's are kind of rare compared to a 350. You just don't hear about them very often.

Case in point:
Just yesterday, I had trouble at at CHEVROLET DEALERSHIP getting the correct OIL FILTER!! Apparently, GM has discontinued the PF35 and its now a PF1218. I bought two at a time. First one wouldn't go on right... and so I tried the other one and had the same trouble. :mad: The threads did not match up to my engine. I had to take them back and go to Napa... There's screwed right on. My point being... even for a generic 350... parts are getting tricky even at GM!!!
 
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You are correct, a stock TBI system would probably will not run a 383..although blueprint engines claims they have one that runs out at 280hp and 380ft/lbs of torque. Might be worth looking into for $3500. However, supposing you start with a bone stock TBI you will need to

1.) Bore out the throttle body and intake to match
2.) Larger injectors (under 300hp or so you can probably get away with cranking the fuel pressure up)
3.) High volume fuel pump
4.) Custom tuned chip (keep in mind with a laptop and simple tools you too can log motor performance, and re-tune and burn your own prom chips)

Some short tube headers and true dual exhaust with a balance pipe will really wake the motor up.

There is no doubt you could make upwards of say 350-400hp with a TBI setup. There are plenty of F-Body guys running around that have done just this. For what you are looking to do 280-300hp and 375-450ft lbs of torque will make that truck scream and is achievable quite affordably with the TBI 383. Actually, I'd probably start worrying about frame twist up in the 450ft/lb of torque range. You can always supercharge the final result for another 125HP and 125ft/lbs of torque though I'm quite sure you won't ever need to.

I still wouldn't discount the oil burner option either, though I definitely would not consider a GM diesel unless it was a duramax. That is not to say that 6.2's and 6.5's aren't good motors, great torque, lightweight, perfect for rock climbing and wheeling but, they do just lack that umph uphill on the freeway and modifications are very limited. A good comparision of the 6.2 is a 305TBI, the 6.5 is about par with a 350TBI if it has a Turbo. A good solid transplant for the money is hands down a Cummins 4BT or 6BT-> (5.9 12V found in 88-98 rams). These motors are notorious for incredible efficiency, longevity, and power (I think the 24V version wsa actually named best engine ever built ny JD power when it first came out). In stock form the 5.9 makes 175ish HP and 450 ft/lbish torque. There are some really easy mods to make to these engines that will for sure turn your truck's frame into a pretzel.

On the 400, I really do not see the point. It is rare, it had cooling issues, and it's not the easiest to find parts for. A 383 is a 350 bored .030" over with a 400 crank, well 400 stroke at the very least. The 400 made it's power because of it's stroke like the 383. 17 cubic inches isn't going to move that truck down the road a hell of a lot better. Heck, get yourself an old 70's 350 4 bolt main block and you can probably bore it to where you drop that margin into the 10ci range. You simply will not gain that much from the 400 over the 383 and it's not going to be any cheaper to put together. I don't see a reason why anyone would put a 400 together unless it's to make a vehicle have matching numbers or something to that effect. I had one, back when I was a kid in a early 70's K5. It was an ok engine, but it wasn't anything to right home about. It's a stroked small block nothing more. Also, the 400 is going to limit you to the old style 2 piece rear main seal and non-centerbolt valve covers,...which are great if you like the smell of burning oil because they are fairly notorious for leaking.
 
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here something i saw in the new petersons 4x4 mag a dual throtle body setup that should work on the 383 no problem
if your still looking for motor ideas what about a 501 caddy tork monster
 
pseudomike,
Great points, man.:D I have built a 383 stroker before and so I know what makes it what it is. Actually, the one I built was a 388 stroker. But that's another topic for another thread. :rolleyes:

As I said, the diesel idea is intriguing. I have no doubt that a Cummins engine would be optimal for the performance/efficiency I am after. But I still think the swap would be more involved than I am willing to dive into. I am mechanically inclined enough to do it, but I gather that it would be quite a headache to get it to operate properly.

Maybe someone who has done the Cummins diesel swap in a truck like mine will chime in and prove otherwise?!? :D
 
I definitely think the 383 will make the most sense for you. It bolts right into your truck without modification, and you can buy any gasket, filter and so on right of the shelf. The exotic stuff is cool for a swap, but the 383 is just logical. Short of that I would do a BBC but your gas mileage will be in the pooper.
 
I think you're right.
I'm hoping that I can get the mpg's of a small block when I'm cruising steady, but also have big block power when I need to stomp on it.

My Dad always had a saying when I'd mention big blocks: "yep, you'll pass everything but a gas station..." :haha:

Well, thanks to everyone who has contributed to my thoughts and helping me consider my options. I had never even considered a diesel swap until this thread. I don't think its the route for me... but it was interesting that so many of you recommended it. Makes me want a diesel in my next "new" truck for sure! :D
 
I think you'll be happy with that setup. I was going to go the TBI 383 route for my re-power...but then I recently stumbled upon a complete Cummins truck and couldn't resist. If/when you get to it and if needed I do have a throttle body that is bored out and a matching edelbrock performer for the TBI. I'm still running them right now but it will be coming out as soon as I get that Cummins yanked, re-sealed, and painted.

Good luck.
 
So what would be the best possible mpg coming out of a tbi 383? I am considering this as well for a suburban I'm looking at getting to be the family expedition/DD rig (I'm glad my wife is as against minivans as I am...LOL) But realistically what would be the best setup on the 383 for best hwy mpg? My mechanic buddy said he was getting 17-18+ out of his dads crew cak k-20? Does that sound like a fish story or is it possible?
 
I'd have to say a fish story..first off GM never made a crew K20. Secondly, the K20 in 4wd form or a K30 4wd crew is most likely running 4.10's in the rear. Lastly, I've never seen a K20 with a factory overdrive which you would definitely need to make those numbers.

Not to say he hasn't modified the vehicle, but there are many variables, gear ratio, trans, motor setup.

The 383 TBI in a K5 setup correctly with L05 heads, overdrive, free flowing exhaust, and a balance of gear ratio to tire size to keep the motor in it's optimal torque range will probably do at best 15mpg combined city/highway. We have a 6.0 Silverado k2500 at work and it get 12mpg at best to put it in perspective. We also have a duramax that has highwayish gears and it pulls in the early 20's.

Brian over a TBI chips has a TBI truck he has been working on to squeeze every bit of fuel economy he can get out of it. It is a 2wd truck with a 5spd and 2.73 gears and I think he's pulling 19mpg combined ~17city 22hwy. You probably shouldn't be so hopeful with the burb. You want to make some MPG's in that beast get a duramax or cummins and run some 3.50 gears with a .70 overdrive and you'll be in the 20's.
 
Another vote for a 6.5L diesel (93 with mechanical injection) with a 5 speed manual transmission and a turbo upgrade for high altitude operation. You'd probably have to up your boost to make up for the lack of air up in the mountains, but that is very easy to do with an upgraded holset 66x turbocharger. Just watch your pyro / boost gauges closely, and fly up the side of those mountains at 70 mph in 4th gear!
 
The 6.5TD is great on fuel but no two ways about it, but it's a light duty diesel, the do not make huge HP or TQ, with a sub or big tires it would simply be a silly swap. The 5.9 cummins is going to blow the doors off the 6.5 and it makes all the MPG's if not better than the 6.5. you don't need a new $5K cummins for that swap. Look for an older truck 92-93 era dodge and you will have a nice transplanter. The things run for eternity.
 
Money is always (or should be) a concern, but practicality should be paramount. My vote is for either a Ram Jet 350 (about $5,500) or install an Edelbrock fuel rail injection system (about $3,000). Either way, you should have all the power you'll need...
 
This thread is O-L-D. But I appreciate your reply PWagon.

I've still not made any engine swap. But every time I see my leaking rear main seal leaving its mark wherever I park :o, this very thread comes to my mind.

I've thought this over for almost a year now, and am still leaning hard towards the RJ 350, as you suggested. You are right... "practicality needs to be paramount". This truck of mine is currently my DD in the winter time. But even after it isn't anymore, I will be towing a boat with it, taking it hunting on long road trips, wheeling it in Moab, etc. I don't want an engine that has hard-to-find parts. The SBC 350 has parts available in every parts store.
 
Yes they did.
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Yep I just saw one last week at my buddies place. You can do a search on here to find out more on them.

Also what is the deal with people knocking the 6.2/6.5? They are good motors for what they were intended for and a turbo wakes them up. A 6.5T with up grades can get into the stock 12 valve 5.9 Cummins power range. On top of that the new AMG 6.5 blocks have a bullet proof bottom end with a higher nickle count in the block castings. It's amazing the stupid sh!t I hear people say about them.
 
I've blown up, and been around a lot of blown up 6.5's. They aren't completely unfounded.

Martin
 
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