Forged crank?

[mattbred]

Where would one buy a forged 4.0 or 4.2 crank? Coupled with forged rods and pistons enough to increase compression to 18:1, or in that area.

 

[1998xj1985]

converting to diesel or what?!?! sheesh that's high. i would try maybe eagle or hesco, a hi-po place like that is probably your best bet for that kind of thing i'd imagine.

 

[5-90]

The Diesel 242ci idea, hm?

Forged cranks? Not unless you're going to make the dies to do it yourself - forged cranks didn't happen for the AMC six (just the V8 engines.)

Forged pistons? I think they're already in the aftermarket.

Forged rods? I'm not sure if a forged V8 rod can be modified for use with the six crank, but I think the same caveat applies as for crankshafts.

 

[mattbred]

Hm yeah thats what I figured. And yeah it's a diesel conversion project I've been thinking about. I wonder if the iron crank with the 7 mains would be enough? Add in some longer forged con rods and pistons, and appropriate valves, and I wonder if it could take the abuse.

 

[gradon]

505 performance. I thought the crank was forged, but now I'm not sure.
http://cgi.ebay.com/ebaymotors/Jeep-Rubicon-AMC-4-7-Stroker-Kits-WOW-L-K_W0QQcmdZViewItemQQ_trksidZp1638Q2em118Q2el1247QQcategoryZ33623QQihZ004QQitemZ140008963046QQrdZ1QQsspagenameZWD1V

 

[JohnX]

505 performance. I thought the crank was forged, but now I'm not sure.
http://cgi.ebay.com/ebaymotors/Jeep-Rubicon-AMC-4-7-Stroker-Kits-WOW-L-K_W0QQcmdZViewItemQQ_trksidZp1638Q2em118Q2el1247QQcategoryZ33623QQihZ004QQitemZ140008963046QQrdZ1QQsspagenameZWD1V

Looks like a stock 4.2 crank.

 

[Dr. Dyno]

No forged crank for the 4.0/4.2 unless you have one custom made.
Eagle forged rods no longer manufactured but 505 Performance have them, and you might find them in ebay.
Forged pistons? There's Hesco, Keith Black KB944, or custom-made items.

 

[92DripCherokee]

theres no way your going to inject diesel fuel into the OE gasoline, spark ignited cylinder head, the valves arent arranged for an injector pointed down at the piston.

-the cam has no lobes to mechanically drive the injectors

-an all electronic piezo injector system would be more expensive to fit than the engine would ever be worth

-the pistons have short skirts, they would slap all to hell with a diesel C.R.

-the block needs thicker walls, webs, mains, main caps. And it needs pressed in liners to be serviceable.

-The jeep 6 cyl crankshaft is lightweight compared to even a small 3 cylinder tractor engine.

There was a Chevy small block 350 diesel, http://www.robertpowersmotorsports.com/DieselWeb.html
Same dimensions, more beef inside.

http://www.sae.org/automag/technewsletter/080108Tech/01.htm
a diesel done right, damned amazing too.

 

[REDXJ4FUN]

FYI the 199 amc six had a forged crank

 

[5-90]

FYI the 199 amc six had a forged crank

Really? But it only had a three-inch stroke tho - so that could be an issue (I don't think we could get Diesel to run in a destroked 242...)

 

[Dr. Dyno]

FYI the 199 amc six had a forged crank

I think that's just a rumour. AFAIK, the 199 crank is cast iron just like the 232/258/4.0 cranks. It's only advantage is that it has a 3" stroke so you can build a destroker engine that'll run higher rpm because the piston speed is lower.

 

[REDXJ4FUN]

well maybe not all the 199s are but there were some that were produced with forged cranks. Be for I have been a AMC nut long before a jeep nut.

 

[Boostwerks.com]

lol 18:1

if you wanted to swap to diesel, compression is the last thing I'd be worried about. More along the line, of how the hell are you going to swap to a high pressure fuel injection that is capable of idling the motor or...glow plugs perhaps? good luck with that. Not to mention your cylinder head isn't designed for a compression related combustion.

The list goes on.

 

[mattbred]

lol 18:1

if you wanted to swap to diesel, compression is the last thing I'd be worried about. More along the line, of how the hell are you going to swap to a high pressure fuel injection that is capable of idling the motor or...glow plugs perhaps? good luck with that. Not to mention your cylinder head isn't designed for a compression related combustion.

The list goes on.

Been thinking about all of those. Don't need glow plugs, can simply use an air intake heating grid similiar to the cummins.

Could take an injection system from another diesel engine that suits the bill. There's a bunch of ways you could engineer it to work.

All it would take is money, and time to see how long it lasts before it explodes itself

 

[Boostwerks.com]

It just seems your money would be much better spent else where.

 

[mattbred]

It just seems your money would be much better spent else where.

Why? A diesel 4.0 would be king of all engines ;p

 

[KMK172008]

buy a cummins. it would be cheaper

 

[Flash]

Lower the compression the 12 or 13:1 and run E-85 pump gas(has a octane rating of something like 110 or 107 compare to 91

Flash.

 

[KMK172008]

you have to upgrade almost everything the eathanol touches if your gonna run it off of e-85. also expect a huge drop in fuel economy. but yea it should make like 250 hp or more when properly tuned to run eathanol

 

[JJacobs]

you have to upgrade almost everything the eathanol touches if your gonna run it off of e-85. also expect a huge drop in fuel economy.

False and false.