The "Pig in a Poke" Stroker
ThisGuyUKnow
Full Time Jeeper
- Posts
- 2,785
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- Location
- Harleysville, PA
- Vehicle(s)
- 1986 CJ7 Laredo 4.0,Nv3550,D300 Twin Stick,AMC20 3.31, 31 BFG
Honda vtx1800c
Ok so strap in for a long story.
I have been getting pretty sick with the TPI AMC 360 project's BS. I'll get it running then it will mysteriously stop with no reasonable explanation. This last time was just the straw that broke the camel's back as the process has been going on for almost 6 months and I have made no progress forward.
Since I have started selling 4.0 conversion harnesses to people (3 sold so far who wants one!!!) I am really starting to miss the trusty AMC I6, mostly because I can make those run fairly easily and I am a whiz at trouble shooting the 4.0 Fi.
With that in mind I have started casually cruising CL keeping an eye out for motor. I would occasionally contact people and ask questions but never really found anything that made me want to drop the v8 cold turkey. Part of the reason was that the TPI 360 would have been such a unique project and would separate the CJ build from the run of the mill builds out there.
So I started including stroker engines in my nightly CL searches. Very pricey engines but occasionally you can find decent deals on them second hand but you can get in trouble quickly if you can't hear the motor run or if the seller doesn't have any paperwork on the motor.
Here is what happened. I ran across a CL ad posted about an hour and a half away from me by a dude who lives in a small town dominated by a large drag strip. I almost didn't contact the ad because the way it was worded I wasn't sure if he had an assembled stroker or just parts to make one. I opted to contact him.
This is the general summary of what he said: The engine is an assembled 4.6 stroker that he got in a running 91 cherokee XJ that he traded another vehicle for. The previous owner wanted to be able to take the jeep to the strip and still be fast with a lift and 35 inch tires so he built out a stroker. This guy took the jeep in on trade and it was his DD, he found the stroker to be too much for him (wuss) so he pulled it and dropped a regular 4.0 in its place. He said that the stroker has under 10k but would need a new timing chain as he robbed that for the 4.0 replacement and that he would take 400 for the motor.
Well this sounds like a pig in a poke to me is what I am thinking. I have this guy telling me that he has a stroker but how can I really tell that without taking a look inside. The 4.2 cranks from cjs are longer in the front and require a spacer to seat the balancer correctly but the YJ 258s have the correct length crank for the 4.0 balancer.
I opted to go take a look and of course it does not have the longer crank on it, which makes it very unlikely that it is a stroker. Sure there is a chance it might be a late model crank but according to what I read on the internet (a statment that often gets us in trouble) the late 70s crank is the ideal crank to use because of the counterweights or something with the later cranks being less desireable. I would imagine if anyone was building a stroker they would know a little bit about what they were doing. Also the guy was like the dude that built this wanted the jeep to be a sleeper, I had to run 106 octane through it (oh so now maybe he isnt looking like such a wuss for not being able to handle the stroker as a dd) because the compression was so high.
However; the head was equiped with a nice set of harland sharp aluminum roller rockers, now that is something that you just can't fake as you can see them. So here is my logic, maybe I am being sold a bag of lies about this being a 4.6 stroker but if someone put roller rockers on a 4.0 I highly doubt they they would simply put a 400ish dollar set of rockers on a junk un modified motor soley just to sell it for 400 bucks. And furthermore I think it is very unlikely someone would install roller rockers and not do other work to the engine.
This is the logic I applied:
For one I just drove an hour and a half to Maryland to possibly buy this motor on a whim which is a long way to return empty handed. Worst case scenario I am getting a junk 4.0 with like sand in the crank or something but it has the rockers on it which i could possibly sell for 250 maybe 300 bucks and then I could make up the majority of the money i spent in selling individual pieces on ebay or something. Maybe break even or maybe just lose a few bucks to "growing pains".
Best case scenario I just got a 4.6 stroker with a late 258 crank, that possibly can be taken to a machine shop and worked a little to run regular pump gas through.
Dropped it off last night at a local machine shop in Schwenksville. He is going to put it up on a stand and pull the bottom off and identify the crank. If it is a 4.2 crank then he is going to pull the head and get measurements to determine the Compression in it. Then we will go from there. If it turns out to be a regular 4.0 crank i am not sure what I will do, if it is a usable motor then I may stick with it.
I will find out tonight after work. The anticipation is a little much. I keep telling myself that I am assuming it is not a 4.2 crank so that I won't be dissapointed but in reality I am really keeping my fingers crossed big time and would be sad if it isnt.
I have been getting pretty sick with the TPI AMC 360 project's BS. I'll get it running then it will mysteriously stop with no reasonable explanation. This last time was just the straw that broke the camel's back as the process has been going on for almost 6 months and I have made no progress forward.
Since I have started selling 4.0 conversion harnesses to people (3 sold so far who wants one!!!) I am really starting to miss the trusty AMC I6, mostly because I can make those run fairly easily and I am a whiz at trouble shooting the 4.0 Fi.
With that in mind I have started casually cruising CL keeping an eye out for motor. I would occasionally contact people and ask questions but never really found anything that made me want to drop the v8 cold turkey. Part of the reason was that the TPI 360 would have been such a unique project and would separate the CJ build from the run of the mill builds out there.
So I started including stroker engines in my nightly CL searches. Very pricey engines but occasionally you can find decent deals on them second hand but you can get in trouble quickly if you can't hear the motor run or if the seller doesn't have any paperwork on the motor.
Here is what happened. I ran across a CL ad posted about an hour and a half away from me by a dude who lives in a small town dominated by a large drag strip. I almost didn't contact the ad because the way it was worded I wasn't sure if he had an assembled stroker or just parts to make one. I opted to contact him.
This is the general summary of what he said: The engine is an assembled 4.6 stroker that he got in a running 91 cherokee XJ that he traded another vehicle for. The previous owner wanted to be able to take the jeep to the strip and still be fast with a lift and 35 inch tires so he built out a stroker. This guy took the jeep in on trade and it was his DD, he found the stroker to be too much for him (wuss) so he pulled it and dropped a regular 4.0 in its place. He said that the stroker has under 10k but would need a new timing chain as he robbed that for the 4.0 replacement and that he would take 400 for the motor.
Well this sounds like a pig in a poke to me is what I am thinking. I have this guy telling me that he has a stroker but how can I really tell that without taking a look inside. The 4.2 cranks from cjs are longer in the front and require a spacer to seat the balancer correctly but the YJ 258s have the correct length crank for the 4.0 balancer.
I opted to go take a look and of course it does not have the longer crank on it, which makes it very unlikely that it is a stroker. Sure there is a chance it might be a late model crank but according to what I read on the internet (a statment that often gets us in trouble) the late 70s crank is the ideal crank to use because of the counterweights or something with the later cranks being less desireable. I would imagine if anyone was building a stroker they would know a little bit about what they were doing. Also the guy was like the dude that built this wanted the jeep to be a sleeper, I had to run 106 octane through it (oh so now maybe he isnt looking like such a wuss for not being able to handle the stroker as a dd) because the compression was so high.
However; the head was equiped with a nice set of harland sharp aluminum roller rockers, now that is something that you just can't fake as you can see them. So here is my logic, maybe I am being sold a bag of lies about this being a 4.6 stroker but if someone put roller rockers on a 4.0 I highly doubt they they would simply put a 400ish dollar set of rockers on a junk un modified motor soley just to sell it for 400 bucks. And furthermore I think it is very unlikely someone would install roller rockers and not do other work to the engine.
This is the logic I applied:
For one I just drove an hour and a half to Maryland to possibly buy this motor on a whim which is a long way to return empty handed. Worst case scenario I am getting a junk 4.0 with like sand in the crank or something but it has the rockers on it which i could possibly sell for 250 maybe 300 bucks and then I could make up the majority of the money i spent in selling individual pieces on ebay or something. Maybe break even or maybe just lose a few bucks to "growing pains".
Best case scenario I just got a 4.6 stroker with a late 258 crank, that possibly can be taken to a machine shop and worked a little to run regular pump gas through.
Dropped it off last night at a local machine shop in Schwenksville. He is going to put it up on a stand and pull the bottom off and identify the crank. If it is a 4.2 crank then he is going to pull the head and get measurements to determine the Compression in it. Then we will go from there. If it turns out to be a regular 4.0 crank i am not sure what I will do, if it is a usable motor then I may stick with it.
I will find out tonight after work. The anticipation is a little much. I keep telling myself that I am assuming it is not a 4.2 crank so that I won't be dissapointed but in reality I am really keeping my fingers crossed big time and would be sad if it isnt.
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