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3.8l swap?

The FWD 3800 uses the GM Metric bellhousing. This is the same as was used in the Cadillac FWD 4.x engines (pre-Northstar), the Fiero, the Isuzu Trooper, and a couple of other vehicles. The Cadillac Northstar is modified version of this pattern. Anyway these are all FWD applications except for the Isuzu.

The 3.8L from the GNX was RWD and has a BOP bellhousing.
This was my thought. Most (if not all) supercharged 3.8s were in FWD cars (Grand Prix, Bonneville, etc) and good luck finding a GNX engine...:D

Why not look into a 4.3? Bulletproof engines. My brothers 99 GMC had 300k+ miles before he did a rebuild, and even then he just had the cylinder walls cleaned up and all new gaskets. Didn't need a bore, cam was still perfect, etc. There's lots of parts for them as well, and they were turbo'd for the Typhoon/Syclone duo.
 
I had a 1999 $400 Bonneville SSEi (L67) with just an intake I found in a dumpster and a sheet of aluminum I found in the trunk used as a heatshield to cover the exhaust cross over. Ran 14.9 in the 1/4 and put down 209whp and 278 ft lbs. Yes the dyno runs cost 1/8th the cost of the car...then again so did a tank of gas. I sold the car for 800 bucks after driving it for 6 months.

That said if I had a running L67 car and an XJ with no 4.0 I'd do it. The supercharger will be pointing at the firewall though. The 4.3 swap is interesting since it 'might' be easy to swap a SBC in later since the 4.3 is a SBC with 2 cylinders missing.
 
The 4.3 missing to cylinders was my choice too for future build plans. I have heard of people being able to bolt in a 4.3 to the stock mounts of a Xj but never seen it. Cool thing is you can find a whole Blazer cheap. You can do a auto (careful some are Manuel valve bodies) like 4L60e to a np241 and stil have driverdrop. Also looking back wish I got a older Blazer with tbi instead of the sypder injection. It fails but can be repaired.
 
The cleanest way to swap in an alien engine is to do the entire driveline. Engine, transmission and the transfer case. Why fight it when you can get a donor? Gives you the PCM and all of the sensors as well...

Then all you need to fab are mounts and a possible radiator depending on where the donor takes coolant.

Trust an old Hot Rodder on this. Donors are the bomb.
 
The 4.3 has half of what the 3800 has to offer as far as fuel mileage.


If I want anything but a 4.0 or a 3800, it would be a 350. Why bother for two less cylinders and the exact same swap.
 
The 4.3 has half of what the 3800 has to offer as far as fuel mileage.


If I want anything but a 4.0 or a 3800, it would be a 350. Why bother for two less cylinders and the exact same swap.

The 4.3 is a truck engine though. It is a true torque monster for a v6. The spiders aren't that much of a problem and respond very well to a new cam. This would be what I would swap.
 
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these are during the project, prior to clearing out all of the extra crap that was in the engine bay. currently it's all apart with a bad rod bearing, but the original engine bay harness has now been stripped out to nothing but dash power supply, and headlight harness, and sensor wiring to make the gauges work.

I drilled and tapped the lower plenum to put the jeep temp sensor below the 3800 temp sensor, and Teed the oil pressure sender out to add the jeep one into the system. the tachometer (86 2.8l) had the exact same tach signal, and volt meter runs off of the electrical system anyways, so no biggy on that.


I had ALOT of fun building the truck, though if I were to do it again, I would do it in an 87 or newer chassis as you will need the 4.0 radiator anyways. the motor was a very reliable motor, and the only problem I ever had with it was the #3 rod bearing became damaged when I was driving on the highway behind some old-ass sunday drivers (who should have either been euthanized or lost their license, at least) for over 20 minutes in 3rd gear doing less than 30mph in a non-pass 55mph zone. I was on the phone and wasn't thinking, so when I had the chance to finally pass the yahoo, I grabbed the shifter and downshifted....as I would from 5th to 4th for a pass. instant redline+ followed by some fun noises.
 
Yeah. You'd have to cut the firewall, or figure out how to move the engine forward...an interesting dilemma since there wouldn't be room to change oil, then
 
jeepcomj I grabbed the shifter and downshifted....as I would from 5th to 4th for a pass. instant redline+ followed by some fun noises.[/QUOTE said:
Bet you felt pretty dumb.
I put the auto jeep in reverse the other day while going about 35. I use neutral on the hills cause of the retarded amount of compression braking and for some reason thought I was going from 3rd to OD. Seems to be a nice emergency brake
 
I did. Result, the truck hasn't moved under its own power in 3 years
 
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