Slant 6 stroker?

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Just swap in the amc designed 4.0 and have a far superior base to work from.

the reputation these motors have for durability and the amount of abuse they'll endure borders on myth, but can they make a respectable amount of power and hold together as well? asking for a friend....
The AMC 4.0 is a good engine but the JEEP cooling systems suck rotten eggs. It suffers from pisspoor compression ratios too. There is a HUGE spread between the Static and Dynamic compression ratios. The stock cams have HUGE overlap.

But the 4.0 has a big bore and shorter stroke so take the crank and rods from a 4.2 (258) with its longer stroke and the 4.0 is now a 4.5L. Over bore it 0.030" and its a 4.6L. At 0.060" over and its a 4.7L.

A 4.7 with a ported head, bit hotter cam in a 1991 Cherokee with full time AWD will smoke many Rustangs.

And like the \6 and the 2.2/2.5 4's, it is not a cross flow head so a bit of loss in "HOP UP" power.

But I think this engine is too tall for most early Abody's. At least for the sloped nose of the 1962-64
 
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the reputation these motors have for durability and the amount of abuse they'll endure borders on myth, but can they make a respectable amount of power and hold together as well? asking for a friend....
I stuffed 28 pounds of boot in my slant with main and head studs using an .020 head gasket. My exhaust pressure was more than boost so it was not as efficient as it could have been with more $$$$. Drove it to the track, raced, then home...
 
I stuffed 28 pounds of boot in my slant with main and head studs using an .020 head gasket. My exhaust pressure was more than boost so it was not as efficient as it could have been with more $$$$. Drove it to the track, raced, then home...
That's a pretty heavy boot. What size do you wear? lol
 
the reputation these motors have for durability and the amount of abuse they'll endure borders on myth, but can they make a respectable amount of power and hold together as well? asking for a friend....
Indeed they can. How does 4 digit power on factory main caps and bolts sound? I'm not at liberty to give out details, but a quick YouTube search might give you some details!
 
But I think this engine is too tall for most early Abody's. At least for the sloped nose of the 1962-64
there's somebody on here doing a 4.0 in a 2nd gen cuda. it's a bit of an undertaking from what i've seen in the thread. and that's just to get it to fit/mount, who knows about hood clearance.

i like the motor, but that wouldn't be anywhere near the top of my engine swap list for these cars.
 
Indeed they can. How does 4 digit power on factory main caps and bolts sound? I'm not at liberty to give out details, but a quick YouTube search might give you some details!
Yeah, check out @JohnFM3 's 'cuda build, it's been an odyssey...but He's been tenacious to put it mildly, lol...
 
funny you mention that...

check this out:

Wow. Another "my chit is gold" eBay seller.

I have a slant turbo exhaust manifold I'd gladly sell for 749.99, undercutting the ad above. Let the PM's roll in!
 
I remember in one of my uncles old hot rod magazine, that there was highly modified Cleveland headed ford six, I always find those type of builds the coolest, wonder if there's a head that could be modded to fit a /6 ?
The Ford 300 and 351C share the same bore and that's about it. Finding a good flowing cylinder head with close to the same bore size as the Slant may be a challenge, but I'm sure there are likely several that exist. Just find someone willing to cut and weld them together. There is an early Hemi that has a 3.500" bore size that would be a fun hybrid head to create....
 
The Ford 300 and 351C share the same bore and that's about it. Finding a good flowing cylinder head with close to the same bore size as the Slant may be a challenge, but I'm sure there are likely several that exist. Just find someone willing to cut and weld them together. There is an early Hemi that has a 3.500" bore size that would be a fun hybrid head to create....
wanna see something CRAZY? https://www.motortrend.com/how-to/300-ford-inline-straight-six-with-ls-head-engine-build/
 
if newland group in china produce this for the Aussie hemi-265. an engine produced in tiny numbers compared with the slant 6.
4340 Billet Hemi-6 265 Crankshafts For Chrysler - Buy Hemi-6 Crankshafts,Billet 4340 Steel Hemi-6 Crankshafts For Chrysler,For Chrysler Hemi 6 265 4.3l Crankshafts Product on Alibaba.com

3.68 standard to 4.25 inch stroke, and a few inbetween available if you can afford it.

i'd guess an enterprising chap could get a slant crank made, i bet there is a mopar blueprint doc for the 225 crank somewhere.......

send it to them and ask for a bigger stroke :)

i guess that expense should be weighed up against say SCAT or someone US based doing the job.

one presumes Newland group know mopar stuff due to doing work for Australian and US based companies. you can have the packaging printed with whatever you want....



Dave
 
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I don't know. I just don't think a longer stroke than 4.125" will be of any benefit. The 225 is already severely "underheaded" so adding additional cubes from more stroke I think exasperates the problem. I think a head like the one I have is probably real close to a "max effort" slant 6 head. I'm really wanting to see how it runs, but even it will still limit the engine. That and the lack of being able to really get the bore out big enough. I'll be happy with "whatever" it does, though. That's just the attitude you need to have, because they won't ever break records naturally aspirated. I say that, but then look what Mark Etheridge has done. Does anyone know if his records have been broken?
 
If I remember correctly, Someone (Crower, I think) made a run of special order "billet" slant six cranks, some years ago. My info is second or third hand, but minimum quantity of 10 cranks at $3,000 ea. If anyone has confirmed info, please correct me.
 
No sure about the quantity, buy Crower will make just a single billet crank if you want one. I know CEEJ over on .org has one for his Slant....
 
I am aware of that. He got one from "group" buy. If I am not incorrect, the original deal was $30,000 for 1 or 10, (engineering, programing, etc) so if the total cost is the same, go for the max. Then sell the excess to recover your cost. Again, my info is not 1st hand, and could be incorrect.
PS: Lunati did a special crank for my 170 back in the '70's. Stroke equalized, indexed, and hard chrome journals at std size. To this day, that crank still looks like new (yes, I have put many runs on it :) ). They also did a "stock eliminator" cam for my engine. It would spec at the factory lift and duration, but had a faster lift rate, and I think a different LSA. Still have that cam here, somewhere.
 
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stroke isn't the issue, bore is. I'd try find the thickest block I could and bore it as much as I could.....then there is the restriction of the head.....
boost is your best bet, TBH
 
Wow. Another "my chit is gold" eBay seller.

I have a slant turbo exhaust manifold I'd gladly sell for 749.99, undercutting the ad above. Let the PM's roll in!
You have a FACTORY Turbo Slanty Ex. Manny.....????? Where & when did that happen??
 
stroke isn't the issue, bore is. I'd try find the thickest block I could and bore it as much as I could.....then there is the restriction of the head.....
boost is your best bet, TBH
No, the biggest problem is the cylinder head. It was never redesigned to suit the 225. The bore is already too big for the head.
 
You have a FACTORY Turbo Slanty Ex. Manny.....????? Where & when did that happen??
No sir, it is not factory. Someone made it from a stock cast iron manifold. It was nicely done however.
 
No sir, it is not factory. Someone made it from a stock cast iron manifold. It was nicely done however.
Many years ago I took a \6 log and cut it into three pieces and scrapped the center. Then brazed a 2 inch pipe to each 3 ports and an elbow curved up to mount a T4 turbo. It lasted for a while but glowing cherry red caused the brass to melt out. Never got around to Furnace welding with nickle rod.
 
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