Destroke? 199 crank in 4L?

sureshot007 said:
The rules for a specific Rally America class limit displacement, and the AMC 199 is almost right at the limit. Since you can swap cranks around with the 258 to gain stroke, can I swap the 199 to lose stroke? Are the cranks similar enough? Has anyone ever heard of doing this?
Click to expand...

www.jeepstrokers.com has a thread on strokers using the 232 crank......Perhaps someone there has some info on the 199.
 
Bear in mind that using the 199ci crank is still going to net you more than 199ci displacement - the bore on the 242 is 3.875", not 3.750".

You'll actually end up about 212ci.

Also, with the shorter stroke, you are going to lose CR unless you have rods and/or pistons made to make up for the stroke you're losing - which is going to be a sharp loss of power. I believe that the deck height on the 199 is lower than the rest, which is going to affect where the piston ends up at TDC as well.

However, the crank itself should fit without any trouble (the AMC 199/232/242/258ci share an awful lot of internal dimensions) with the catches noted.

What limitations are you trying to work within?
 
3313cc (pushrod), NA, and the engine block needs to be the same as the chassis manufacturer (AMC/Jeep/Chrysler).

I figure that pistons are easy to find, rods can be modified, but cranks are a lot more expensive to have modified. So if the crank fits, I might be able to find the appropriate rod and pistons to give a high compression ratio. It was just a thought I had earlier today, and was just trying to research if it's A) possible, and B) a good idea or not.
 
It will work...I had been tossing around the idea of using a 199 crank in a Turbo charge app since it has more journal overlap and would take more abuse. Some one ran the numbers on a NA 4.0 block with the 199 crank a couple years ago and at least in the digital world it looked really good

xoom xoom xoom
 
sureshot007 said:
3313cc (pushrod), NA, and the engine block needs to be the same as the chassis manufacturer (AMC/Jeep/Chrysler).

I figure that pistons are easy to find, rods can be modified, but cranks are a lot more expensive to have modified. So if the crank fits, I might be able to find the appropriate rod and pistons to give a high compression ratio. It was just a thought I had earlier today, and was just trying to research if it's A) possible, and B) a good idea or not.
Click to expand...

Thread discussion going on at http://www.jeepstrokers.com/forum/viewtopic.php?p=28521#p28521
Basically you're going to need:

4.2L block (+0.030" cylinder overbore)
199 crank (displacement will be 3310cc)
4.0L rods
Sealed Power Z233P30 pistons
Shave ~0.065" from block deck
Either bush the rod small ends or lightly modify pistons to accept 0.931" pin.
 
I'm at a point where I have some decisions to make regarding the future of the team.

I can either:

  1. Stay Group 5, and just drive it like it is
  2. Stay Group 5, and stroke it/high compression/turbo/supercharger/etc
  3. Stay Group 5, and swap in a V8
  4. Switch to Open, with the previous engine choices, but go 4wd
  5. Switch to Open Light, and build a 3.3L motor
  6. Get a different car
As you can see, there is no clear right answer. I don't want to switch to a different car, but the Jeep is heavy and the 4L doesn't exactly have a ton of performance potential as compared to a 5.7 Hemi or LS1. Open Class is on par with a death wish, if I want to be competitive at least. Open Light presents a competitive class without getting crazy with speed. But this engine restriction is killing me.

After everything is said and done, a 5.7 swap will make more power and be more reliable than anything I build for the same price. But if I can get a 3.3 straight 6 to rev to 8k with 11:1 compression, it could make some respectable power.

And the worst part is that making these decisions is compounded by the idea that I have to be ok with balling it up and walking away at any point. So that makes it hard for me to want to invest a ton in a custom engine.
 
6.0L LQ/LS motor + XJ = win
 
I suppose that the HEMI isn't a bad choice if you can stay in your current class. Not sure about the cost, etc on those tho. Are stroker motors allowed? Could always do a 318/392 stroker or a 360/408?
 
Here is the problem with strokers: heavy and not rev happy.

An aluminum 5.7 weighs less and makes more power. Plus, it will actually rev, making it useful for racing. Strokers are great for torque, but I'm not driving a tractor trailer. If I could get a 10 lb flywheel, I'd entertain the idea of milling the crank down in the hopes of actually getting it to spin up quickly. I've thought about the Hesco crank sensor relocator, but I'd still have to do a custom flywheel, or use a Camaro flywheel and clutch (if the dimensions are close enough). But if you add the cost of a new flywheel, clutch, and crank sensor kit, I'm halfway to a junkyard hemi. Plus the head on the 4L is terrible for high rpm airflow.

Engine options alone make switching to an S10 a good idea. If I could just hit the lottery, I could build an awd V8 GMC Safari and make it look like the A Team van. Then all I'd need are some SFI approved gold chains...
 
Yeah, that's quite a decision...
I would think that a Magnum series 5.2L, cam'ed and with a slight raise in CR, would move the Xj pretty nicely. I don't know the weight difference between that and a 4.0.
HEMI swap sounds expensive. Veery expensive. Correct me if I am wrong.
Stroking the 4.0 is probably the most reliable and lowest cost solution for keeping the I-6. Turbo'ing it you are collecting parts & tuning it a lot to get it right. There is a 5lb Boostec kit out there for a few thou.
Hmm.
I'd either swap a built 5.2 / 5.9 or add a blower kit. Building a de-stroked engine w/ a 199 crank etc is still going to keep most of the limitations of the 4.0 (head design, mostly) with an uncertain outcome. Probably run like stink but it is a lot of money for "probably", breaking new ground & all.
 
Oh crap, I forgot that forced induction engines are limited to 3.3 liters, so turbo'ing would probably be out anyway.

I have a 5.2 in my garage, but it's not aluminum, so it's just as heavy. Cam'd and tuned, it can make power, but a stock 5.7 makes more right off the bat.

Hemi swaps are exactly cheap, but ebay has them for between $2500-$3500. I know, not exactly pocket change, but compared to buying a crate motor, it's cheap enough. Plus, V8s are awesome.

In the end, I'll probably end up with a high compression stroker. I have an extra motor kicking around that I can build at my leisure.
 
sureshot007 said:
Here is the problem with strokers: heavy and not rev happy.

An aluminum 5.7 weighs less and makes more power. Plus, it will actually rev, making it useful for racing. Strokers are great for torque, but I'm not driving a tractor trailer. If I could get a 10 lb flywheel, I'd entertain the idea of milling the crank down in the hopes of actually getting it to spin up quickly. I've thought about the Hesco crank sensor relocator, but I'd still have to do a custom flywheel, or use a Camaro flywheel and clutch (if the dimensions are close enough). But if you add the cost of a new flywheel, clutch, and crank sensor kit, I'm halfway to a junkyard hemi. Plus the head on the 4L is terrible for high rpm airflow.

Engine options alone make switching to an S10 a good idea. If I could just hit the lottery, I could build an awd V8 GMC Safari and make it look like the A Team van. Then all I'd need are some SFI approved gold chains...
Click to expand...
I was referring to the ones I noted, as in the Mopar 318 which is typically stroked to 392, and the 360 which is typically taken to 408.

Going the S10/blazer route would work.
 
You must log in or register to reply here.

Similar threads

D
Romoving crank with engine in vehicle
Replies
4
Views
911
dktool
D
N
Powertrax no slip failure
Replies
8
Views
2K
Redsnake
R
C
New Jeep...new problems!
Replies
0
Views
388
CheapJerokee
C
C
New Jeep...new problems!
2 3
Replies
44
Views
3K
CheapJerokee
C
K
Long crank time
Replies
15
Views
2K
kstopp
K
Back
Top