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1983 Scrambler "STUMP JUMPER". Frame off, 5.3 Conversion.

Dang, Dennis- I'm away for a couple weeks and you go crazy! That's how I like it! 400 Horse... I had planned on a 4.8 in my 81 but it looks like I'll have to go with a 5.3 just to keep up!

I agree on the column shifter and no console. That's going to be my route- I will have a low profile console, lower than the seats, just to give the dog somewhere to sit and hold some important hardware...
I missed you my friend. Yes, I picked up the cam, springs and push rods today and if the heads are ready I think we will try and tackle this project Saturday. It's going to be interesting to see just how much horsepower this will add. I'm hoping the next trip to the chassis dyno shows about 340hp at the rear wheels. Oh, some kid in a Camaro decide he wanted to show off yesterday, the look on his face told me he had never been smoked by a Jeep before.

If anyone knows where I can get a tilt column with a 4speed shift on the stick let me know. I also need some hardware room.
 
I know Dakota Digital makes a gear position indicator. Most 70's or 80's columns are suitable too. There are companies like Ididit that can make a column to your specifications...but they're proud of them.
 
I know Dakota Digital makes a gear position indicator. Most 70's or 80's columns are suitable too. There are companies like Ididit that can make a column to your specifications...but they're proud of them.
Almost everything I buy it seems like the seller is proud of it. I think I have fool tattooed on my forehead. lol Guess I'll be calling Ididit. I think I bought my present column from a place call Columns Galore or something like that.
 
IIRC, late model GM full size vans come with "4 speed automatic" columns, but I am not sure if they would be the correct length for a CJ :shrug:
 
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This is how Stump Jumper looks today getting ready for his heart transplant Saturday.
Heads and cam.


 
The new cam and heads are now installed. Stump Jumper now has a bada$$ sound and improved horsepower and performance, it's not as much as I was expecting but I'll get it on the chassis dyno for a upgraded tune soon and that should help. It's hard for me to believe but it looks like I actually picked up about 2 MPG with the change. I also may need to look at the torque converter now. I still wish I would have gone with 4.88 gears instead of the 4.10's.
 

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Stump Jumper was back at the dyno today after the heads and cam mod. Almost 300HP at the rear wheel and 350 to 375 at the flywheel. It is now where I wanted to be. Stump Jumper must think it's a race horse now because we were out looking for Mustangs on the way home.
https://youtu.be/8AOrB2USyLg
 
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Now that your engine has lost vacuum with the camshaft change, a hydroboost will be in your future-

Sent from my SM-G920V
 
Dang it you know everything. LMAO It's not as bad as I thought it would be.
 
Congrats! Do you have a dyno chart you can post?
 
what heads and cam did you use?
 
what heads and cam did you use?
I used a set of 243 heads and a custom ground cam from Engine Power Systems. Turned out to be the right choice with the 4:10 gears and the 4L60E tranny. I said in an earlier post that I had wished I would have gone 4:88 gears but with the engine mods the 4:10's are really quick. I hope to post a another video soon.
Oh yea, Cha-Ching, this mod put me over the $45,000.00 mark. Yea, I'm sick, but it's Randy and Erricks fault.
 
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I used a set of 243 heads and a custom ground cam from Engine Power Systems. Turned out to be the right choice with the 4:10 gears and the 4L60E tranny. I said in an earlier post that I had wished I would have gone 4:88 gears but with the engine mods the 4:10's are really quick. I hope to post a another video soon.
Oh yea, Cha-Ching, this mod put me over the $45,000.00 mark. Yea, I'm sick, but it's Randy and Erricks fault.

Sorry.... Not really! :evil: Looks and sounds great. I've got a lot of catching up to do....
 
I took Stump Jumper on a trip today with mostly country roads and averaged 17.1 MPG. At 65 MPH the Scangauge showed 19-20 MPG. I think that's pretty nice for a 350+HP engine. As for the 4:10 gears, at 70 MPH I was running 2200RPM's. I think I hit it right on the head with this one.
 
What shocks me is we added over 60 hp to the engine with the cam and heads and still picked up almost 4 MPG in fuel economy.

I'm a true believer that you can get better economy with more power, depending on how you drive. Spirited driving will reflect the increase. You won't see an increase if you drive like a little old lady...
 
I'm a true believer that you can get better economy with more power, depending on how you drive. Spirited driving will reflect the increase. You won't see an increase if you drive like a little old lady...

Well I ain't no little ole lady.
 
Stump Jumper just turned 3,500 miles since the build and is doing great now. With the addition of the 243 heads, a more aggressive cam and a really good tune the Scrambler is now at about 400 HP at the crank. My only negative is now with the high lift cam I have lost a significant amount of manifold vacuum which leaves me with less braking power.
I might need to switch over to Hydro boost braking. I was just wondering if anyone has experience with using an electric vacuum pump. Any help would be appreciated.
 
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