I've been posting about my progressing driveline build here:
http://forums.amceaglesden.com/index.php?topic=22813.0I cover rebuilding the front diff here:
http://forums.amceaglesden.com/index.php?topic=43409.0Cliff Notes:
'90 4.0 HO
Stock flywheel, stock clutch
'00 NV3550 transmission
NP229 T-case modded for Eagle use
D30 3.54 disco front from 4 cylinder Eagle
D44 3.54 NON-C-Clip rear axle from '87 Wagoneer
Rear disk brakes from '98 Grand Cherokee
Yet to come:
Eaton Detroit TruTrac in front diff
Eaton E-Locker in rear axle
With the 4.01 first, 2.72 low and 3.54 axles, I end up with 38.6:1 crawl ratio. That's not shabby.
I can at a later time swap in an NSG370 + NP241OR for a 63:1 crawl ratio. That's getting up there.
In this thread I'd like to discuss aspects of the 4.0 swap.
First: Fuel injection electronics
I've heard that a Chevy Blue Flame Six distributor can be used in an AMC/Jeep six by using an AMC V8 distributor gear. I will do this so that I have an HEI distributor available for future system changes.
However, my plan is to get the thing running with stock Jeep electronics.
I have a '91 or so Cherokee wiring harness.
I expect that I'll be able to rework starting system, charging system, power distribution and fuse box so that electrically the car looks like a Cherokee. I've done a lot of wiring in my time, and that doesn't scare me at all.
Does anyone have any "Gotchas" for transplanting the Jeep system?
Second: Brakes
Has anyone done a rear disk conversion?
My D44 rear will have disks from a '98 Grand Cherokee.
This means I'll need to use a different master cylinder in order to have enough fluid volume to move the pistons and have reasonable front to rear brake bias.
Is that as simple as using a Grand Cherokee master cylinder?
I already have a reman booster ready to go in.
Third: Exhaust
The stock 4.0 manifold and exhaust routing is the primary consideration when building the new differential snout bracket. The fitment is ticklish, but with enough fit/futz cycles, I'll get it to work.
I *should* be able to make a stock Jeep exhaust pipe work. However, the pipe wants to go under the transmission bellhousing. I'm not sure that's going to be a great fit with the NV3550 trans.
They used the same basic exhaust routing from '90 through '99, but the NV3550 and a new split exhaust manifold design with dual O2 sensors came out in '00. This design wraps BOTH pipes around the front of the oil sump and then merges them on the right side of the engine by the bellhousing. This is obviously incompatible with the Eagle front diff.
Fourth: VSS and Electronic Speedometer
I'll be using a Jeep speedometer drive sleeve and 36 tooth driven gear. I'll use an adapter from Jags That Run or a similar part to generate the VSS signal for my ECU.
http://www.jagsthatrun.com/SpeedSensors_Order.htmlI would like to convert to an electronic speedometer as well. I see there are a couple of topics on that in this forum. Is there a definitive guide or method?
Fifth: Fan adaptation
This shouldn't be hard. The Eagle mounts the fan on the waterpump. The Jeep mounts it on a dedicated fan pulley on the right side of the engine below the A/C compressor.
The Jeep and Eagle waterpumps use different bolt circles.
Because of the serpentine drive, the Jeep waterpump pulley sits a little back from where the Eagle waterpump pulley sits.
This leaves enough room for a simple bolt circle adapter which will allow me to bolt the Eagle fan to the Jeep waterpump.
Sixth: Engine driven air compressor
Since the Jeep fan pulley will be reduced to a simple idler, I might as well do something with it.
I think I can space the A/C compressor bracket, which mounts both the A/C compressor and the fan pulley, away from the block and insert a mounting plate between the bracket and block.
The mounting plate will extend back behind the bracket several inches and will bolt to the side of one of the old York single cylinder A/C compressors.
I can move the compressor clutch up to where the fan pulley is and then drive the compressor via a shaft coupling.at the back of the bracket.
Then I have an engine driven air compressor. Because the York compressors keep their oil supply separate from the gas they're compressing, they can be used for air just as easily as for refrigerant.
Anything I missed?