6.5 to carb 350 swap

[beejkuz]

Thanks Hardrock for the info. I've talked to the previous owner and he said it had a pretty serious knock to it when he parked it, but he really couldn't remember for sure because this all went down 5 yrs ago. so maybe it just may need main bearings, maybe a bent valve who knows. I beleive that the 208 can be rotated to a driver side drop by splitting the case and rotating it 180 never did it, i just heard........ if nothing else change the input shaft on the existing t-case. If i end up keeping this truck a 6.5 i will probably rebuild this engine thats in it anybody know what a rebuild kit goes for?

[PitchBlackC3]

Rebuild kits for the 6.5 are pretty high.
I have a 95 K3500 SRW that I got with a knocking 6.5TD in it. It actually ran and drove when I got it, but bad knock down low.
I used a 96 c2500 5.7L as a donor and did the swap.
I used the 4L80e that was in the truck, but use the torque converter from the gasser. You don't want the diesel torque converter behind the gas engine, stall is way too low.
The big problem I see with your setup using the carb is you will have to devise some way to control the 4L80e. It has to have some kind of electronic control. The standalone kits for it are pretty expensive too.

[RedHeartbeat]

Transgo HD3 kit for a full manual valve body, no controller needed.

[PitchBlackC3]

Transgo HD3 kit for a full manual valve body, no controller needed.

That is true. Can't imagine I would like driving one like that though. Not a DD anyway.

[Hardrock]

Don't let anyone scare ya away from the 6.2/6.5TD engines. They're not Durabux or Powersmokes, but they were never designed to be.
They're simply durable, reliable, IDI diesel engines for MEDIUM DUTY work. (if you get a good one to start with)
99.9999% of all the busted up, trashed out 6.2/6.5TDs
out there got that way because the guys driving them
either didn't know squat about diesel maintence, or they were trying to pull the hinges off hell with'em.
If you try to pull grade all day long with 25-30K GCW, and your foot on the carpet, they're not gonna last long.

On the other hand, if you want to do what they were designed to do, they can last 400,000 mi.+

They'll work as hard as a big block gasser, maybe a little harder, and do it on less cost/mile to operate. That's what they were designed to do, nothing more.

There's very little you can do to mod one without sacrificing longevity. Lots of guys trying, lots of broke motors. You just have to know the design limits of a given engine.
Ya might want to investigate the 6.5 that's in there a little more. I've bought 6.2/6.5's that knocked bad, only to find a drippy injector, or an injector line banging on a hold down, or a bracket. Some bust the center out of the flexplate. Some have burned out glowplug tips banging around on tops of pistons, some have the precups loosen up in the heads and knock.
One lost a rocker arm retainer and went dead on one hole.
The '94-ups can loose track of TDC and the ECM will pull the CSA too far. Smoke and knock alot.....

Half the time, when you find a 6.5 sitting, nobody really knows what happened to it. It just went poca,poca, brrr, pop,pop, whiish....Most guys know gassers and think it's fried.

Anyway, if you MUST swap in a gasser, get yourself a TCM for the 4L80e out of a '92-'93 6.5/4L80e truck, or a '91-'93 6.2/4L80e van. You can run the trans with that.
It's sole purpose is operating the 4L80e on mechanical injected 6.5 trucks. Your '94 does it with the PCM that also operates the electronic injection pump.
AFAIK, you can't just use the trans programming in your '94 without throwing code on the engine managment side of things. Some guys are running later LS PCMs with carbed engines and '80e's. You can probably disable all functions but the trans managment but that requires a tune.
Good luck!

[Sizzle Chest]

Anybody got the low down on replacement 6.5s? There are the new supposedly upgraded blocks such as the Optimizer 6500, P400, etc. Read you can get them from Peninsular Diesel as well as a few other dealers. Then of course there are plenty of companies offering remans. The remans seem hit or miss and there are a lot of warnings out there around chinese made parts. Hard to decipher it all. Anyone know the whole scoop?

There have to be good ones out there, as 6.5s are still going in millitary humvees to this day.

[beejkuz]

Thanks again for all the info. The cheapest controller i could find is goiing to run about $500. guess I'll cross that road when i come to it.
I now have come across a engine out of a 89 1/2 ton pretty sure it is a 305. Only problem is that it has about 350k on it. Will the intake and heads bolt onto the older 350?

[gottaswapup]

seems you're dead set on going to gasoline, and I can't say I disagree. The 6.2s are better engines than stock-castings 6.5s are, but putting a 6.2 in place of a 6.5 is illegal. Any trans that bolts up to any Chevy gas V8 will bolt up to the 6.2, and therefore the 6.5 which was a thin-casted evolution of the 6.2. Thus the blocks and heads always crack , unlike the 6.2s. Now, as to 305 heads on a 350. It is a direct bolt on, but may not be a good idea. First, does the 350 have dished pistons in it? If not, forget the 305 heads, even if you live at high elevation. Next, which 305 heads are they? If they have centerbolt valve covers, you'll need to pop an intake valve out to see if they're swirl-port or not. Swirl port will make good torque off idle, but will run out of air by 3500 rpm. And at 350,000 miles, the heads could've already been rebuilt a time or two. If a SBC is a 100,000-mile virgin, then the heads are not suspect if they're not cracked. But are they free? If not, spend $76 for a pair of used Vortec 350 heads from your local Pick-N-Pull. These also need dished pistons for truck use. Using these with flat-tops is for guys with lightweight cars.

[beejkuz]

My computer crashed bout a month ago so i havent been able to update. since my last post i have decided to abandon the gas conversion and keep it a diesel, considering i basically figured that i had strip every thing out of 2 trucks to do so. Depending on how much damage the 6.5 crankshaft has, i may rebuild it or throw a different engine in it. i can get a 6.2 out of an 84 van that runs great for very cheap. would putting the heads and intake work on the 6.2, or would i be better off keeping it a 6.5? i wouldnt be against keeping the 6.2 non turbo if the throttle and trans would work.