4.6 is it real or not

[project88mj]

is there a such a company who takes the 4.0 and bores and strokes the motor to be a 4.6 ?

 

if not how much money would it take?

[rockhardzj]

Hesco, Golen, etc...

[DirtyComanche]

And there's lots of guys that do it in their back yard/garage.

[Drahcir495]

is there a such a company who takes the 4.0 and bores and strokes the motor to be a 4.6 ?

 

if not how much money would it take?

YES! I may be getting mine from here http://www.titanengines.com/Products.html and here are two build-up links that should give you an idea on what is involved/cost

http://www.bc4x4.com/tech/bryce/stroker/stroker.cfm

http://www.angelfire.com/my/fan/stroker.html

[rockhardzj]

I think Golen does them up to a 4.7 Stroker. Beyond 4.7, I think its all custom machine work at a machine shop. I believe you can top the 4.0 out at about 5.0 MAYBE 5.1, but IMHO, a 4.7 is probably pushing it to it's limits.

[Eagle]

The difference between 4.6L and 4.7L is how oversize the pistons are. I think (but it has been awhile since I did all the math) if you take a stock 4.0L and just drop in the 4.2L crank, you get 4.5 liters. If you bore it .030 over you get 4.6 liters, and if you bore it .060 over you get 4.7 liters.

 

I rebuilding an old (used) 4.0L block it's unlikely you can clean it up without boring to at least .030 over, so in all likelihood if you plan to build a stroker you'll be looking at 4.6L or 4.7L no matter what you try to do. the practical limit is .060 and 4.7 liters. The blocks can be bored larger ... sometimes ... but only of they have been checked to verify that the cylinder bores are prefectly centered in the cooling jackets. If the blcok had "core shift," going larger than .060 may punch through the wall. Cooling is also a problem on the vary large bores, because the walls are of uneven thickness and you encounter problems with heat transfer and hot spots.

 

The basics of this are that the 4.0L is an AMC engine built in the same engine family as the older 4.2L and the even-older 199/232/258 cubic inch in-line six engines. This engine family all use the same crank journal spacing and the same crank and rod bearing journal diameters. So it's just a matter of using a 4.2L crank (which was a longer stroke and smaller bore) in the 4.0L block.

[DirtyComanche]

You can theoretically off-set grind the crank and get 5L out of one. The reality is that it's not a good idea. Maybe not even possible from a practical point. The money invested makes no sense at that point, and reliablility could easily suffer.

 

 

I don't know of one that has gone that far.

[rockhardzj]

You can theoretically off-set grind the crank and get 5L out of one. The reality is that it's not a good idea. Maybe not even possible from a practical point. The money invested makes no sense at that point, and reliability could easily suffer.

 

 

I don't know of one that has gone that far.

I did see it once, at the 4wd Jeepfest back in like 04 or 05. It was done, but I doubt that engine still runs today, unless it has been really babied.

 

My guess is something that massively bored out would suffer from cracks caused by the high heat in the block, and the cracks would form between the cylinders. That would be engine failure at it's finest.

[pingpong]

There is a lot of work involved in doing this yourself. A guy in the local club Chris did it, and by the time it was all said and done he had close to 2500 in a 4.7 stroker :eek: Which seems like a lot to me, comsidering most of the parts were given to him like the 258 block, and a HO motor :eek:

[feerocknok]

There is a lot of work involved in doing this yourself. A guy in the local club Chris did it, and by the time it was all said and done he had close to 2500 in a 4.7 stroker :eek: Which seems like a lot to me, comsidering most of the parts were given to him like the 258 block, and a HO motor :eek:

IMHO, $2500 would be much better put into a different *cough*V-8*cough* motor... It seems like people eventually just get hung up with brand loyality instead of simplicity or effectiveness.

[JeepcoMJ]

what did the 4.2 come in, and what else is necessary to install one?

 

I assume timing would be off...how would you correct that?

 

what pistons/connecting rods would ya use

 

how well would this work with a renix system?

[Oizarod115]

what did the 4.2 come in, and what else is necessary to install one?

 

I assume timing would be off...how would you correct that?

 

what pistons/connecting rods would ya use

 

how well would this work with a renix system?

IIRC YJs were available with em til the end in 95

[DirtyComanche]

what did the 4.2 come in, and what else is necessary to install one?

 

I assume timing would be off...how would you correct that?

 

what pistons/connecting rods would ya use

 

how well would this work with a renix system?

IIRC YJs were available with em til the end in 95

 

 

Yeah, and they came with the worlds crappiest carbs. So normally they run like $#!&. Which means lots of YJ guys pull them and put in V8s. So you can get them cheap.

 

 

And the same time, a guy can pull his 4oh and put in a V8.

[Pete M]

The carbed 4.2L died with the 90 YJ. In 91 they got the MPI H.O. 4.0L like the MJ/XJ. :D

[Oizarod115]

The carbed 4.2L died with the 90 YJ. In 91 they got the MPI H.O. 4.0L like the MJ/XJ. :D

m preeetty sure they still got 4.2L even after the introduction of the 4.0 ill have to double check though

 

k yeah i checked, confused cause i knew they were offered at the same time as one another but i thought it was up til the end. so yeah what pete said!

[Limeyjeeper]

Hi,

I am new to this forum but not jeeps. I built a WJ stroker a few years back and was a frequent contributor on Jeeps unlimited. One of the best places to go for info on strokers is this site. http://www.jeep4.0performance.4mg.com/. Dino really knows his stuff. You can also see a link to my stroker build up on the WJ. Ended up with a 4.7 pushing around 265hp. It was quite the adventure.

I now have a 1991 Comanche which will get a stroker - (one day) and a complete renovation.

 

Photos on my WJ build up are here.

http://www.printroom.com/ViewAlbum.asp? ... &curpage=1

[akamcbird]

am i to understand i can swap a crank shaft from a 4.2 into my 4.0 and have a 4.5? what else is involved, what kinds of side effects would this have, and how much hp/tourque could one expect

 

btw... amc eagles are equiped w\the 4.2

[Pete M]

It is both easier and harder than it sounds.

 

http://www.angelfire.com/my/fan/stroker.html

http://www.jeep4.0performance.4mg.com/stroker.html

[Eagle]

The primary issue when doing a "budget" stroker is that you need to use the 4.2L connecting rods with the 4.0L pistons. The journal and wrist pin diameters are the same, so they bolt together. But ... there is a minor difference in overall deck height, which results in slightly excessive compression if you use all stock parts. Various people have looked at ways to overcome this without spending a ton on money on what started out as a low-bucks rebuild. This is one area where the Renix shines, because having a knock sensor really helps. You need larger injectors so you can run rich enough to not make things worse due to a lean-burn condition.

 

The old Strokers e-group site had a bunch of people looking for aftermarket stock replacement pistons with enough meat on the top to allow milling out a dish to reduce the compression ratio. You can also help it along by cc'ing the chambers in the head to a larger (and uniform) volume, also reducing compression ratio. And it works better with an RV type cam that has enough overlap to bleed off some compression pressure.

[possum]

Yeah a V8 sounds much easier to do. And it isn't too hard or expensive. I got a bowtie 350 under the hood and it works great. And cooling isn't bad if you make sure and really thin the coolant out with water.

[Oizarod115]

Yeah a V8 sounds much easier to do. And it isn't too hard or expensive. I got a bowtie 350 under the hood and it works great. And cooling isn't bad if you make sure and really thin the coolant out with water.

ever try that water wetter stuff? what is it purple ice or somethin?

 

do you run a 4.0 rad?

[feerocknok]

There's a bunch of coolant additives at the auto parts places.

You guys with 4.0s should try em, because my 2.5 never gets up to operating temperature and all you guys do is overheat.

It gets hard to sell a product you don't know anything about.

[possum]

Purple Ice works wonders. And I am running a 2.8 Radiator.

[carnuck]

Purple Ice and Water Wetter are excellent. I dropped my 4 cyl to just around thermostat rating with an old rad while climbing in Moab and Ouray in '02.

 

 

I have a '91 4.0L block bored with 0.030 pistons and 4.2L rods and crank to go in (the crank and rods came from my Mexican 282 motor that was swapped into my '83 Eagle from a Mexican CJ, then I swapped the motor to my '83 Cherokee after the Eagle was damaged by a hit and run driver and the 999 died for the 3rd time)

Were I to do it over again, I would get a billet crank with extra stroke to reach the top of the bore, steel liners on all cyls and 4.0L pistons with the Hesco aluminum head and the new roller cam (about to be released for sale on the Strokers list) to run LPG. High compression is no prob with this setup as LPG is good to 11:1 if it's not cut with Butane to drop it from 130 octane. Natural Gas is even higher with @160 octane.

 

That would put this motor in the $3,000 range and it'll pull @375 HP and 400 ft lbs of torque at 2400 RPM.