What all does an engine swap entail?

[trooper Tdiesel]

so the trans bolt pattern is the same.
for a small block GM 350 and the 6.2/6.5L diesels



3,500 rpms is quite high for a 4BD or 4BT engine

2,800ish rpms is commonly red line for these engines.
so re-gearing to 3.55/3.08 range would be needed to turn mpg friendly rpms at 60 mph


i know the 4BD and 4BT model is around 750lbs + trans how does that compare to the 6.2L 6.5L?

[oil pan 4]

To get the best MPGs you need a 2wd, OD transmission like the L460E or TH700 and 3.08 or taller gears.

Build a ram air intake like this:
11 inches of water, no more. - Diesel Place : Chevrolet and GMC Diesel Truck Forums

And convert to electric fans.
Turn up the injector pump.
Put on 31 inch tires.

The engine you get will likely be a "C-code", put a duel plane "J-code" intake manifold on.

And run at least 8 degrees of advance.

A free flowing forward of the rear axel dump exhaust too if you can. I didn't see a big mpg boost from this but it was part of my 25mpg+ setup.

[oil pan 4]

Originally Posted by trooper Tdiesel

so the trans bolt pattern is the same.
for a small block GM 350 and the 6.2/6.5L diesels

Yes, SBC, BBC, I6, 4.3L, LS serries, duramax, 6.2/6.5L diesel all share the same bolt pattern. I know there are more those are just the ones I am aware of. There are some spacing differences between the flexplate and torque converter when going from a old vs new style trans.
Drive shafts between TH700, TH200, L460E and T56 are all the same.
Also 4L80E and TH400 and possibly 6L80E are the same drive shaft.

Originally Posted by trooper Tdiesel

3,500 rpms is quite high for a 4BD or 4BT engine

The DB2 serries mechanical pump is limited to 4400RPMs.
I have ran my 6.5L into the speed limiter, it screams.
Electronic DB4 (which you will avoid at all costs) are limited to 3400-3600RPMs.

Originally Posted by trooper Tdiesel

i know the 4BD and 4BT model is around 750lbs + trans how does that compare to the 6.2L 6.5L?

The 6.5 is close to the same weight as a small block chevy.
The SBC with TH700/4L60E would be around 600lb.
The 6.5L with transmission would be under 750lb.

If you want to lose several hundred pounds:
remove the rear seat
Remove the spare
Do a lithium battery replacement: DIY: BYOB, for more power, a lot less weight - Diesel Place : Chevrolet and GMC Diesel Truck Forums

[drmiller100]

Originally Posted by oil pan 4

The 6.5 is close to the same weight as a small block chevy.
The SBC with TH700/4L60E would be around 600lb.
The 6.5L with transmission would be under 750lb.

ummm, NO.

sbc is about 600 pounds with exhaust and iron intake, wet. Drop that to

trans is about 170 pounds with TC.

aluminum headed 5.3 is about 100 pounds lighter.

6.5 weight appears to be 750 complete.

Keep in mind the 4l60e won't hold up to the 6.5 - it requires the 4l80e which is another 100 pounds heaiver yet.

So, 6.5 with 4l80e is only about 1000 pounds. but don't forget to upgrade the rear differential and driveline and radiator and fan. all require bigger ones for the diesel.

[me and my metro]

Gm built thousands of 6.2 powered 1/2 ton truck, Blazers, and burbs. The reason my 1 ton 6.5 na only gets 17mpg is because it has 4.56 gears for trailer towing. I had a stone stock light duty 3/4 ton 6.2 2wd pickup w/ 4.10 gears that got 21 mpg all day long.

[oil pan 4]

My 6.5 has a TH700R4 which is a mechanically controlled 4L60E.
Works fine.
So no you don't have to have a 4L80E.

Most turbo 6.5L engines have the TH400 or 4L80E.
My 6.5L has a standard half ton 10 bolt rearend.
Has worked fine for well over 250 thousand miles.

An all cast iron 350 weighs about 600lb.
That 6.5L cant weigh more than 700.
The turbo and turbo manifolds would add at least another 50lb, so is 750lb with or with out the turbo?

[Waerben]

So with the 6.2 I wouldn't have to mess with any of my transfer case or differentials or their gearing correct? I could leave that all stock and have to preform minor adjustments to the transmission to be able to accept the 6.2? Like I could keep my stock radiator, instrument panel, ac comp, alt freion lines. Everything will bolt right on? Or I need the parts made for that engine? Will that engine literally bolt right into the same engine mounts that my 350 is in now? I wouldnt have to adjust anything? My driverraine or engine? No spacing issues no moving anything?

[drmiller100]

you have to change the brake booster to hydro, or figure out a big vacuum pump.
you have to redo the freon lines, IF you can find a 6.2 with an AC compressor.
new radiator.
you will have to wire up a glowplug system, which is actually pretty easy.

I do not know about the transmission - doesn't the diesel require a special torque converter?

Again, if he has a 4l60E he is screwed. If he has the 700r4 it would be easier.

And a BIG question - will it pass emissions inspection???? At the least he will have to unhook the computer or cut the check engine light.

[roosterk0031]

I'd start keeping an eye out for a donor vehicle. 6.2 with 700r4 would be the easiest (no electronics)

1984 chevy 2500 van

122k & $1000

Not close to you but something like that would work, would have to change the tailshaft to match you xfer case but not a big deal.

[Waerben]

So where exactly would i find the flexplate and torque converter that i need for going from the 700r4 to the 4l60e? Is there a kit online that i can use or something? Because i do have the 4l60e. Emissions aren't an issue. I live in texas in a small town. Most everyone runs straight piped. So emssions are not an issue. But I would really like to keep my transmission! i have read on the internet that they are better and stronger than their mechanical cousins.And from what i understand because i have a tbi 350 the computer controlls both the engine and transmission. So technically would the check engine light even work anymore? Because the only computer equipment would be the trans controller right?