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  Topic Review (Newest First)
06-21-2021 07:33 AM
gwistrup I'm building this Jeep for a client who owned it since high school and it had been sitting for 20 years. He originally wanted to put a small block Chevy in it but I convinced him to modify the 6 cylinder because it is less common. I think the 6 cylinder is "cooler" because everyone puts Chevy V8s in them. Clifford Performance has been around forever and I figured they would be a good source for information and parts. I followed Larry's advice on everything I did to modify the engine. He said the combination I used should double the HP and torque. I used an Isky 270 cam, milled .060" off the head and installed the Clifford dual Weber intake and header kit. Part of the reason for the dual Weber carburetor setup is for the visual appearance. It looks cool and it sounds really neat because I made an exhaust system including the 6 into 2 header that goes into an X pipe and then into a Flowmaster dual inlet/single outlet muffler. The tubing before the muffler is 2 1/4" and the tailpipe is 2 1/2". The Jeep isn't registered yet so I have only driven it up and down my street a few times. It seems significantly stronger that it was in stock form but it needs a thorough road test to really see how it performs. The owner is really pleased with how it looks under the hood and how the engine sounds so I have checked off 2 out of 3 boxes of his requirements. If what Larry at Clifford told me is true, it should be equivalent to a stock small block Chevy. I guess that is why they advertise "6=8".
06-19-2021 07:38 AM
Matt1981CJ7 Nice work on finding a solution to your problem.

This is the first time I've seen the dual Weber setup on a 258.

I'm curious, what performance gains do you expect with your new engine configuration?

06-19-2021 07:21 AM
gwistrup Yes I can. I had to move the rod at the firewall from the bottom of the bracket to the top of it to gain enough clearance to remove the top of the master cylinder. There is about 1/4" between the support rod and the master cylinder clip. That is enough room to remove the top.
06-19-2021 06:30 AM
keith460 Are you still able to install/use the left grill support rod coming off the firewall?
Seems like the MC would interfere with the rod since you shifted the MC to the left for clearance of the Weber's.
06-18-2021 08:59 PM
John Strenk Looks great!!!

Thank for reporting back.
06-18-2021 11:39 AM
gwistrup I figured I would post how I resolved my carburetor interference problem. Thanks to everyone for all of their input. I didn't really want to change the carb orientation and throttle cable if I didn't have to. I moved the brake pedal pin that connects the brake pedal to the booster linkage assembly from the right side of the brake pedal to the left side. Moving the pin allowed me to use the original linkage from Jeep and it gave me over an inch of clearance between the rear carb and the dual diaphragm booster that I used to replace the stock 9" Jeep unit. I drilled some new holes to the left in the firewall to mount the linkage and booster and elongated the hole for the linkage rod to go through. Now the booster is moved to the left but the pedals stay in the original location.
05-13-2021 11:25 AM
gwistrup I have talked to Larry several times and he has been helpful with the setup to make it run right but not as helpful to make them fit. He did supply more spacers with the carbs and manifold but they won't do any good. Height is not the problem. Width is the problem. He did say that if there was a stalling problem around turns, you should install an electric fuel pump. I believe that I have found a 7" dual diaphragm brake booster that I can mount directly to the firewall. I am going to measure it again and order one with the brake pedal kit. I would prefer to leave the carbs as they are if I can. That way I won't have to change any of the hoses and other hookups.
05-12-2021 10:30 AM
John Strenk That looks like so much fun.

Did you call Clifford?
Did they supply any spacers? That note was just under the 258 / 4.2 section. I don't think it was jeep specific but everything else I think is wider than a Jeep.

Looks like you might have enough room to turn them 180 degrees. Since they are center hung floats, that won't make a difference which wrong way you mount it...
It probably won't matter in a Cj but I had a car that had a Weber on it and it was great in a straight line or making a right turn. But pull some G's in a left turn and the fuel would run to one side of the bowl and keep the float valve closed... Finally had to put some baffles in the bowl to make it work.
05-12-2021 10:07 AM
gwistrup Here are some pictures of what I have now.
05-11-2021 11:46 AM
gwistrup Thanks for the pictures. Turning the carbs 180 degrees might work and I can see that the throttle hookup is kind of like it was connected from the factory with the cable coming up from underneath. It looks like you would gain about 1.5" clearance with the carbs orientated the other way. The intake and carbs came assembled as shown. I just installed the intake and header as they came out of the box. I read Larry's note about the 8" booster and carb spacers before I purchased the system. An 8" booster is still too large and you would have to cut a hole in the hood to space the rear carb high enough to clear the stock booster. I wonder if the note pertains to a different make vehicle. I will put up some pictures when I get back out to the garage. Thanks again, Gil
05-11-2021 10:02 AM
John Strenk If there is room. I'd also go with turning them 180*

There was this note on Cliffords web site:
NOTE: You MIGHT have to purchase an 8 inch Power Brake Booster. We have added spacers to raise the carbs for clearance.
05-11-2021 08:26 AM
stripperguy Whoa!! I completely missed the fact that you have a dual Weber set up
The 180 flip might still help though

Send pictures of your current linkage.
05-10-2021 08:04 PM
Hoover7 As I understand, the big hurdle is finding a way to attach/coordinate the synchronous throttle linkages on the dual Webers with the OP's power brake set up without interference with the booster. The aft carb is positioned on the #5 cylinder intake, which interferes with the booster. Turning it 90* complicates joining the throttle linkage between the two 38's. Would think [email protected] would have run into this before. Cool setup, hope to see it running-

05-10-2021 06:51 PM
Originally Posted by gwistrup View Post
Could you please show some pictures on how you hooked up the throttle linkage? Also could you measure from the center of the carb to the center of the valve cover? I'm curious how wide your intake manifold is compared to mine. Thank you. Gil
I assume you're asking me...
Here you go, pics taken moments ago
I would call center of valve cover to carb center about 8-1/2"
Throttle cable comes in from bottom of bracket, bracket mounted to side of carb adapter, Clifford intake

05-10-2021 07:47 AM
gwistrup Could you please show some pictures on how you hooked up the throttle linkage? Also could you measure from the center of the carb to the center of the valve cover? I'm curious how wide your intake manifold is compared to mine. Thank you. Gil
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