305 in a YJ ???

[92yjw\\305]

Hey,
All my friends are running around in big chevy pickups on 39's with big loud small blocks. I was wondering what would be involved for a successful installation of a 305 in my 92 wrangler. I know that the mounts would be different but I wasn't sure if the bellhousing would be different. Also i dont want to bust up my stock drivetrain with the extra grunt from the V-8. The transmission is a AX-15 if that helps any. I just mostly like the sound and rumble of a V-8, if I could find a way to make an I-6 sound like a 305 then i'll just do a of another I-6.
Any response would be appreciated,
Jim

 

[Bounty__Hunter]

The '92 4.0L is a good engine, I'd think long and hard about changing it just for the 'sound' :roll: But if you must, get a powerful reliable v8 like the 350, or better yet a 327. Anything beside the meager 305

 

[Snitty]

transmission swap

actually... if you get a good header, and a free flowing soundbox on that baby... the 4.0 sounds pretty damn good.... but if you want the v8 sound, you will likely have to go with a v8.... though... there is rumor of a flowmaster that will alter the soundwaves of a 6 cyl and make it sound like a v8... but to me... that is wrong to do... like the ricers that put fake blowoff valves on their cars, or that put holes in their vacuum lines to make it sound like a turbo....

what 305 are you considering.... the ax-15 can hold up to a 305 for the most part... but i would not suggest putting it behind one, especially a tpi... but if you are going carb or tbi, it would be ok... they are not really any more powerful than the 4.0ho... the tpi does have a few more horses though.... but.... you would be paying for the bellhousing adapter in any way you go, if you go that route, so it would be the best idea to bring over something like a T350, or a 700R4 or an NV#### if you are swapping a v8...

any more questions?? ask away

 

[92yjw\\305]

My engine has 166,000 miles on it. Do u think my engine lost alot of power over time or is it the same as a new engine. I did some research and if a put headers free flow exhaust and a couple small engine mods, the 4.0 would make same if not not more power than the 305. I hope thats right so i can just do a direct swap. And if i decided to go with a 4.0 where would I find a cheaper used one.

 

[Bounty__Hunter]

Rebuild your 4.0L, bore and stroke it for 4.5 to 4.7L displacement. Hi-flow intake and Flowmaster exhaust, you'll be good to go. You'll be in small v8 power range and sound.

 

[Snitty]

I am ALL ABOUT the stroker for the 4.0... yeah, yours might be tired at this point... the stroker kit is a "homebrew" kit... you can go with a 4.5, 4.6, or a 4.7... some have gone up to a 4.9, but it is not a good idea... then yes... you can get the horsepower above 230.. and the torque above 320... now that is pretty good.. much better than even the 305tpi

 

[92yjw\\305]

Anyone in CT wanna go wheelin????? (please)

What would i need to do in order to bore and bore my engine. My knowledge of this stuff tells me that boreing is makeing the cyliunders larger and stroking is a kits of special pistons. Correct on this stuff if I'm wrong. How much would all of this cost after its over and done with. I can take the engine out but I'm sure someone is going to have to bore it for mean. Then depending on the complexity, I might be able to put the stroker kit on and drop her in. Sorry about all the dumb questions but I'm really serious about doing this and I dont want to screw it up.

 

[92yjw\\305]

!! I meant want would I need to do in order to bore and STROKE my engine. !!

SORRY

 

[Utah_jeepster]

A bling bling for Tug....lol

First to have your block bored oversize you need to pull it and take it down to a auto machine shop. The cylinder walls are made from harden stainless steel and you need either a carbide toolling or for a good boring machine ceramic inserts on a high speed boring head. A good auto-machine shop will have the machines and tooling to do this job.

To stroke an engine involes a spacer plate on your crank journels and installing a diffrent crank with a longer throw, making your "stroke"(one cycle of up/down movement of your piston longer.

 

[Bounty__Hunter]

Never heard of the spacer plate, but could be, I dunno. I thought to stroke the 4.0L was to install the crank and maybe rods from the 4.2L, and bore it out to the desired overbore and displacement.

 

[Utah_jeepster]

there is a way doing that is to use shorter pistons...the term stroke, stroking the motor is refering to adding a diffrent crank that throws a longer stroke.
Since the crank arms are longer than stock you need to displace either the piston top I.E. short pistons or push the crank lower.
Either way what your doing is adding a bit more to the torque the motor produces by giving the piston longer time to use the combustion of that cylinder.
There is a down side to this that it wears your valve springs and valve seats since the compression is greater. It also shortens the life of the rings due to the same fact.
The best way to produce high torque with a V-8 was best show by International Harvester with thier 345 cid 10 to 1 long stroke motor in the late 60's to early70's it had over .192 extra stroke length than any 350 motor of its time.

 

[92yjw\\305]

Then do you think i'll be better off finding a amc 304, rebuilding it and slapping that in. Or do you think a mildy worked 4.0L would be sufficient. I need a little bit more grunt with a nice rumble for the rice burners to listen to. Another idea i had was to get a beat 4.0L from a junkyard, that was the around the same year as my jeep(92) and rebuild that with a torquey cam, duel exhaust header, new head, and intake. Hopefully i would get some power from those goodies. But this alos has to reasonable on gas b\c it is my daily driver and i am only a 17. I need a pro's opinion. Thanks guys!

 

[Snitty]

a 4.0 upstroke kit uses the crankshaft and the connecting rods of the 258... the 4.0 has a stroke throw of 3.41", and the 258 has a stroke of 3.90"... that is JUST about a half inch difference... then the 258 connecting rods are JUST under a quarter inch shorter than the 4.0 connecting rods... and since the stroke would increase about a quarter inch each way.. this works out great... the rods and crank are the ONLY things that need replaced to make the stroker motor... but it is suggested to pull the motor anyway to perform this operation to make it easier... so you might as well get the bore done anyway...

the only modification needed for the crank is at the end of it, there is an extended nose at the end of it where the harmonic balancer mounts... you need to address that by either getting it ground off, or spaced to fit... and while the motor is out... and you have the crank there... get the harmonic balancer, crank, and flywheel balanced as a single unit... that will help keep the motor running more smoothly

 

[92yjw\\305]

How can u space the end of the crankshaft to fit? And can I find most of these parts at a junkyard, and how hard are they to get out, incase i'm tearing them out of a junked jeep.

 

[Snitty]

it is better to get the nub machined off... but to space it... once you see the application, you'll understand it... you can use washers, or get something machined to fit... but if you are getting something machined, or even getting the assembly balanced... you might as well have the machine shop take care of the end of the shaft as well...

from a junkyard, you'll want a crankshaft and connecting rods from a 4.2... all of your stock bearings will still fit in the stroker motor

if you really want to do it right.. you should get a complete engine kit from autozone... those are just over 500 bucks... but you get everything.. all bearings, seals, choice of cam, pistons, and crank, new valves, lifters, rods, timing chain, gears... everything... at least that's the deal they had going here