Pajero 4d55 diesel to 2.6 astron

[Paddles]

hey guys,

just picked my self up a 1983 pajero swb for a couple hundred bucks. body and interior are great but it has a 4d55 2.3l turbo diesel which has a very impressive knock. lol, im thinking of replacing the diesel with a 4g54, the old swb pajero came with a 4g54 as well.

basically my questions are if anyone knows is if the 4g54 bolts straight in to existing crossmember and up to gear box and whether i need a narrow block or wide block 4g54??

something i have heard or read is that i will need a pajero 2.6 sump cos they are reversed compared to a sigma/scorp astron??

i know this isnt a 4x4 forum but thought i would try it first.

Paddles

[Billsy]

arent the 4D engines based on an astron block. its probably a direct bolt in

change engine and change the fuel system and go.

[Paddles]

put the car up on ramps last night and measured and bottom 2 bolts on gear box and it measured 330, so it is wide block. looks like it will bolt straight in, just need a pajero sump that is reversed and clearance for front diff.

[rob020]

have you checked if the 4d55 sump bolts up to the 4g54? it might just work

[toruhiwi]

A lot more to the conversion than you think.

Most important one is diff(s) ratio. The diesel is governed at 4000rpm (from memory) so you will find it is mated to higher ratios.
i.e. Your Pajero will be a slug.

Then there's power steer pump, oil pickup, etc etc

Roger

[rob020]

ive always thought of using a diesel alternator with a vacuum pump to run constant vacuum to the rocker cover and do away with the pcv shit... would a 4d55 alternastor have the built in vacuum pump?

[SE Wagon]

Most important one is diff(s) ratio. The diesel is governed at 4000rpm (from memory) so you will find it is mated to higher ratios.
i.e. Your Pajero will be a slug.

Certainly important to consider, but in this instance, he's more likely to have low (numerically higher) ratios than high.

2.3 TD = 4.875, 5.29
2.6 / 2.5 TD = 4.625, 4.875

http://www.outerlimits4x4.com/viewtopic ... sc&start=0

If he has the 5.29 gears he will have great take-off, but highway cruising will be "busy". The 4.875 won't be too bad. I have 4.875 diffs behind my V6 shorty, and stock gearing wasn't too far off my Galant's gearing (in terms of km/h per 1000rpm).

[toruhiwi]

ive always thought of using a diesel alternator with a vacuum pump to run constant vacuum to the rocker cover and do away with the pcv shit... would a 4d55 alternastor have the built in vacuum pump?

You will likely find too much vacuum at the wrong time, end up sucking oil from the crankcase..........to where??

SE Wagon, thanks for those figures. I'm surprised, but gee, you guys are on the ball.

Roger

[rob020]

hmm... mabye if there was a way to regulate the vacuum... i wqas thinking all youd need is a breather on the rocker cover and an oil/air seperator between the rocker cover and the pump... then another breather on the outlet of the pump?

[Paddles]

didnt think about using the diesel sump. oil pick up is not a problem, i can make something to fit. diff ratios have crossed the mind but not really worried about it, ill see how it drives and change them if i had to. it will be used for a bit of off roading and towing trailer or boat when i head camping, ill keep the ute for work, and other cars for play. lol, i was really just looking for something to play with over winter and the pajero popped up.

[Paddles]

anyone know if i can swap a wide block bellhousing with a narrow block bell housing, to fit a narrow block motor?? the pajero has a wide block gearbox, was wondering if i could change bell housings to suit a narrow block motor.

[astronturbo77]

the bell housings are part of the gearbox, unless its a borgwarner box but sure pajero's have a wide jap 5sp

[Paddles]

pajeros do have a wide block gear box, i know that, i was just wondering if the bell housing could be changed to a narrow bell housing???

they both have same internals, just different sizes.

[astronturbo77]

the bell housings are cast to the gearbox. best get a wide block engine

[rob020]

ive got a borg warner and a narrow block bellhousing here if you want, save me takin them to the tip... but yea, jap boxes are one piece, you cant change the bellhousings

[Paddles]

that is cool guys, thanks for the replys, ill just build another wide block motor, enough sitting in the shed.

ROB, i would be interested in grabbing the borgy and bell housing though??

[rob020]

well theyre still the one piece at the moment....

send me a message or giv me a ring before you come up cause i work night shifts (0437086313)
also, the exhaust flange on the diesels is reversed.... ive got one of those catalytic converter manifolds here if you want it...

[Paddles]

ill contact you closer to the weekend and sort something out. cheers.

[Cipher124]

Hmm... Has anyone thought of putting one of these diesel Astrons into a Sigma?

Doesn't sound too common, but an interesting idea!

It would probably require a different diff ratio tho, otherwise it would be revving it's nut off at freeway speeds