just confirming things... I remember that years ago at the dealer you could get a NEW one for around a grand?? but no longer..am thinking if I can find a short block and use my 3.9 heads and front cover etc..? comments?

the engine in the disco is gonna give up soon(leaking from the pan gasket? and ran low(really low) on oil last week as it huffed and choked a bot when i added oil and re-started! :eek: so as Elisa is pushing to sell the OPS for a couple grand NOW!!! I need to be able to probe to her I can re-engine the beast for dirt cheap...yeah I kknow...Mike? feeling charitable with that 4.2? :D didn't thknk so...my friend has an 89 rangie parts rover. is the engine any less powerfull thatn the '95? I know it has the different head bolts(as in less on teh 95, but that is simple th fix...)
or should I install a gm 4.3? :eek:

comments?

Paul(really really want to keep the disco....but am thinking I may need to mothball it for now and et teh series III re-frames ASAP and start driving it??)

95 and 89 should be roughly equal, both are 3.9L. 4.0 had different block/heads/head bolts.

i forgot.

www.car-part.com

95 and 89 should be roughly equal, both are 3.9L. 4.0 had different block/heads/head bolts.
was what I figured..but wondered if slightly different hp forsome reason???


so..just the difference in less head bolts in my engine which would be left out in the 89 when i remove heads to re-do just in case as it had overheated if I recall.....than keep my '95 heads for the eventual 4.2 or 4.6 shortblock if I ever find it for a deal....or should I bother..

Paul(really prefering to upgrading than just replacing the dying engine...)

I have a couple of 3.5's. The intake on a 3.5 is unmarked so you could tell everone its a 4.6. :flipoff2:
-Jeff

you dont have the extra head bolts. that wasn't until the 4.0 which was a mid year '96 thing. even then sometimes it was only the plenum that changed.

:flipoff2: land rover

jeff- i have an early 89 3.9L (verified by casting #) that has a 3.5 plenum on it from the factory. land rover parts bin stuff.

The compression ratio is higher on the 95 3.9's, can't remember which year it was increased. The increase translated to improved torque and hp numbers. Not sure if it is different pistons, perhaps a thinner headgasket or different heads

--Kris

you dont have the extra head bolts. that wasn't until the 4.0 which was a mid year '96 thing. even then sometimes it was only the plenum that changed.

:flipoff2: land rover

jeff- i have an early 89 3.9L (verified by casting #) that has a 3.5 plenum on it from the factory. land rover parts bin stuff.

umm... wrong!(assuning yo meant to say I Do ahvre the extra bolts??)
my '95 does not have the lower head-bolts even though they say 95's should, I was told this before too...and was why I was sold the METAL head-gaskets that fawked me over back last year whick caused the damage to teh engine..i have the newer block, but have the distributor front cover....strange...do I ahve a 4.o with old timing cover and acc? hmm!

paul

I am I the only one who knows this shit?

All 89s had unmarked plenums even though in the US they were 3.9s. Why? Well everywhere else they were still 3.5s and we got the 3.5 plenum.

89 block will fit in a 95 disco. Most (all I believe the cut off was in 94????) 95 discos have the composite gaskets. So you have to use that.

The front covers are different. 95 discos have the serp belt style front cover with the circular gear thing.

I "think" 95s did not have the extra row of head bolts as the were elminated concurrently with going to composite gaskets.

Low oil should not be an issue with a rover engine. It will be ok. I have seen them run with 2-3 quarts for thousands of miles, lifters will be shot and rattle but they pump up after driving a bit.

Ron

The compression ratio is higher on the 95 3.9's, can't remember which year it was increased. The increase translated to improved torque and hp numbers. Not sure if it is different pistons, perhaps a thinner headgasket or different heads

--Kris
yeah was what i had thought and was afraid to take Joe's '89 engine lst year so replaced the #2 piston carnage...despite the damage to teh cylinder...anyone have the definative straight dope here? I do NOT want to go down in power here...the newer engine has a THICKER gasket, being tehcomposite one.. so that's not it...but the piston I removed was different than teh one Pendy origionally sent me...os maybe it's a piston-top difference?

Paul(maybe i need to start scouring teh local junk yards for a wrecked disco/rangie???? I hear they are showing up now...)

There is a very very slight difference in power (like 3 ft/lbs of torque) between the two but the blocks are the same.

All US spec have the high compression pistons.

You will not notice the difference between the two blocks except if one is in better condition.

Ron

The official engineering change to 10 head bolts was dated June 15, 1995. However, there are instances of composite gaskets being used on production engines as early as mid-94.

The only difference between a 3.9 block and a 4.0 is the cross-bolting of the mains.

The differences in cylinder heads are limited to presence/absence of tapped holes in the end auxiliary mounting bosses.

'94 and '95 had the crankshaft driven oil pump, but have distributors. '96 had crank driven pump, but no distributor.

All NAS '96 MY trucks had the 4.0, distributor-less ignition.

More head info... The way I understand it the heads that are not drilled for the outer head bolts (4.0-4.6) are 26cc heads and were designed that way to keep the compression ratio up with the new composite head gaskets. The older heads (3.5-3.9) are 28cc heads and when used with the composite gaskets lower the compession ratio enough that you can burn regular gas (unless the heads have been shaved). I've got 3.5 heads on my 4.6.

Paul,

My 4.2 is sitting in the garage untouched since I left Vegas. I do have the head bolts for the metal gasket still (need to return them if I don't use 'em I suppose), so you could potentially put the heads on with metal gaskets and keep the compression up. I haven't had the heads off, but could get them done for about $150 for the pair and have them mill a few thous. off for you (to keep up the compression).

Things you'd need to get to make this engine run would be a water pump (I could get it and install it too), dizzy, valley gasket, end gaskets and all of the injection from the valley gasket on up.

I have all the brackets for the alt., ps pump, etc... if your Disco stuff won't translate over.

Or you could use your Disco front cover and keep your serp. belt setup.

This engine has the Cloyes double-roller timing chain already, but the cam/lifters are original.

I could feel pretty generous, but remember that the price of the engine would now include some way to actually get it to you (shipping, driving here, etc...).

Lemme know.

"The only difference between a 3.9 block and a 4.0 is the cross-bolting of the mains."

Additionally the crank and main bearing jounals are bigger on the cross bolted blocks, the crank "snout' is also about .75" longer.. Flexplates and flywheels will interchange on the crank but the earlier auto boxes use a different torque converter which requires that you use the proper early flexplate.

OK, other than the differences due to the different engine management systems, DIMENSIONALLY, they are identical :D

"The only difference between a 3.9 block and a 4.0 is the cross-bolting of the mains."

Additionally the crank and main bearing jounals are bigger on the cross bolted blocks, the crank "snout' is also about .75" longer.. Flexplates and flywheels will interchange on the crank but the earlier auto boxes use a different torque converter which requires that you use the proper early flexplate.

I can also verify(by experience :rolleyes: ) that the rover engines are pretty strong when it comes to dealing with oil starvation. I'm amazed my engine is still running after the abuse I gave it with the failing oil pump(had to get home).

You can put a 4.6 in a 101 if you wanted... Bolts "right in" with only the front cover and the extra crank length to worry about... (nd of course the managment system) To fix the crank length just grind the teeth off an old lower timing gear and use it as a spacer between the lower pulley washer and the pulley.

A quick dumb question while we are on the subject............are the later model ('98) 4.0 and 4.6 blocks identical? Is it just a longer stroke crank on the 4.6?
Both have cross bolted mains and big journals don't they?
:confused:

Is it just a longer stroke crank on the 4.6?

This is true..

The problem is that the crank for the 4.6 is not bad cost wise but the rods and pistons are EXPENSIVE!~!

I have sitting in the shop a 4.0 block with a reground stroker crank that should net me 4.8 L and 9.75 CR using 327 rods and 2.3 Ford pistons... All for half the price of building a 4.0 into a 4.6

Did you regrind the 4.0 crank or is it a Buick part? :confused:

sorry for lack of description, I reground a 4.6 crank... The buick 300 crank is a problem if you want to fit up the rover clutch, or deal with late model parts on the front of the engine... So much so that i plunked down the bux for a new 4.6 crank..

You can put a 4.6 in a 101 if you wanted... Bolts "right in" with only the front cover and the extra crank length to worry about... (nd of course the managment system) To fix the crank length just grind the teeth off an old lower timing gear and use it as a spacer between the lower pulley washer and the pulley.

Why grind off the teeth. I need a PTO winch.

JP