More Power!!

More Power!!

Petescj

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Location
PA
Vehicle(s)
1982 CJ-7 258 / T-18 / Dana 300 31 in All Terrains.
1978 CJ-7 304 / TH 400 / Quadratrac 32 in Mud Terrains
I got the Scrambler all legal like now but its down on power. Theres emission stuff on this baby I never saw before. Some of the hoses are dry rotted but it idles pretty good. It gives me the typical Cj start up,pump the gas a billion times and then fire it up. Mileage is aroung 14mpg. :( It seems down on power as well. What upgrade should I throw at it first?

A. Mc2100 or the Weber in For Sale

B. Ignition upgrade

C. your option here
 
I got the Scrambler all legal like now but its down on power. Theres emission stuff on this baby I never saw before. Some of the hoses are dry rotted but it idles pretty good. It gives me the typical Cj start up,pump the gas a billion times and then fire it up. Mileage is aroung 14mpg. :( It seems down on power as well. What upgrade should I throw at it first?

A. Mc2100 or the Weber in For Sale

B. Ignition upgrade

C. your option here
ok I am up for the a and b
c is all about torque.
power is one thing but torque rocks the 4x4 world. and we can do that with gearing. Set up the axle gearing so the jeep is drivable on the road but does not go to fast, then see how it crawls, if it needs more low gearing do that in the transfer case, remember we use these on and off road so we need a balance here. I do not think many of us on thos site are into trailer queens. Balance means works well on the street and works great on trail.
 
I here you . I dont think I should have to re gear yet since Im only up to 31 in. tires. I havent checked the gear ratio yet though. It just seems sluggish. I put a mc2100 and did the team rush on my 85. The difference was amazing. Problem is I did them both at the same time so I couldnt tell you which one was the bigger gainer if there was one.
 
id do the carb first if it has a carter carb.
 
A new carb, better ignition, and a header will make a huge diference in drivability.
 
Im leaning that way. It has the carter only its not the later cp controlled one. Since it gives me the same pump till your leg hurts to start , Im thinking thats first. Weber or Mc2100?
id do the carb first if it has a carter carb.

All very good options but which first? Im thinking you have them in order.
A new carb, better ignition, and a header will make a huge diference in drivability.
 
I would do carb header in one move. That combo will make it easier to live with and give you more bottom end and torque. Then add a better ignition as $$ allows. You will see a huge diference in performance right across the board.
 
I'll check the boards for a used header. I wanna save a little $$ to put that other CJ8 under a tarp for winter.
I would do carb header in one move. That combo will make it easier to live with and give you more bottom end and torque. Then add a better ignition as $$ allows. You will see a huge diference in performance right across the board.
 
a 82 probably has 2:73 gears, not good for anything,
You know I'm a V8 guy so I say go 360 or 401, with efi, no more power problems.
Better yet a efi chevy 5.3 or 6.0 :eek:
 
No No SAY IT ISNT SO. Im gonna have to check the ratio. If thats where Im at, :mad:, Definate R&P change.
a 82 probably has 2:73 gears, not good for anything,
You know I'm a V8 guy so I say go 360 or 401, with efi, no more power problems.
Better yet a efi chevy 5.3 or 6.0 :eek:
 
i have a motorcraft and love it. webers are good but you also might have to buy a fuel regulator to go with it. if not it will flood your motor from what ive seen on those other jeep sites.
 
i have a motorcraft and love it. webers are good but you also might have to buy a fuel regulator to go with it. if not it will flood your motor from what ive seen on those other jeep sites.

I use webbers on my I-6 engines. I have never heard of having to regulate fuel into a carb from a manual pump before. Most people just run jets 2-3 times bigger than they need and flood the hell out of their engines, then blame the carb.
 
Carb, ford tfi parts for the ignition & 4 pin chevy module plugs gapped to 45, a heddman header or nothing.

Remember the key to torque is velocity not volume, same for intake and exhaust.
 
Just my opinion; Buy the Weber carb that's for sale here. A Motorcraft 2100 is a great carb, some have been quoted as saying the best designed 2 barrel carb ever. But, they were never designed to be used on a 258 c.i. L6, that means that they require a lot of tweaking and tinkering to get them tuned in correctly. And depending on what you have and what you're looking for Motorcraft carb parts are kind of hard to find. A Weber is designed specifically for what you are putting it on, there are books written on how to tune them, and they have great factory support.

If you can get your hands on a used header, awesome, but if you can't. Getting rid or your cat converter and installing a high flow muffler will help, not as much, but it will still help.

As for the ignition, everyone has there opinion on what the optimal way to go is (not that I've ever argued about it or anything) :D. So far though, I really like my Summit box and coil. And doing the carb swap first, and then the ignition box I can tell you that getting rid of that Dura-spark module made a huge difference in idle, acceleration, and gas milage.
 
The most bang for the buck I have gotten from a 258 was from a TFI ignition upgrade. It was more impressive than the 4.0 head conversion w/3 angle valves, the header or the carburetor upgrade. This was on My 81 J-10. I am putting a MSD-6 capacitor discharge on the CJ with a motor craft distributor. They tell me it will light diesel fuel when fired from gate posts in a barb wire fence. We shall see. The 77 CJ has a notoriously poor ignition system but the 81 should be pretty close to what you have. Except for the price of the coil it was just a tune up with the cap rotor and wire from a ford 300 cid l6.
 
Ah the infamous Team Rush upgrade. I just grabbed a weber for it online for $50. I'll be doing an ignition upgrade as well , just not sure wich one.
Except for the price of the coil it was just a tune up with the cap rotor and wire from a ford 300 cid l6.
 
I did the HEI on mine, I had a problem with something in my ignition, I think it was the module itself, but the previous owner had hacked wires and taped them it was a mess... so I figured replacing all 3 parts with one and a 2 wire hookup was the way to go. fired up on the first crank after dropping the new one in.

Now I need to get rid of this POS carb. dunno what it is...it's a single barrell and leaks fuel from everywhere.
 
Thats the Carter bbd. Not a fan as most people arent. Give me this weekend and then a week of driving my Scrambler back and forth to work and I'll let you all know how I feel about the weber. I'll have a Mc2100 on standby just in case Im not fond of the weber.
I did the HEI on mine, I had a problem with something in my ignition, I think it was the module itself, but the previous owner had hacked wires and taped them it was a mess... so I figured replacing all 3 parts with one and a 2 wire hookup was the way to go. fired up on the first crank after dropping the new one in.

Now I need to get rid of this POS carb. dunno what it is...it's a single barrell and leaks fuel from everywhere.
 
The last time I ran a "6", I had an Offenhauser Dual Port Dual Plane aluminum intake, A Holley 390 cfm 4v carb with all the off-road mods. A fresh three angle valve job, milled the head for more compression, A Clifford six into two header dumping into a FlowTech Terminator muffler two 2 1/2" in 3" out. MSD 6AL with Ford cap convertion. Cilfford cam & Dual roller timing chain.
She ran sweet, but it still wasn't a 401V8.;)
 

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