I'm in the process of picking a carb for my 97 351 roller engine that's being converted to 4v for my cj8 scrambler. I'm keeping the stick heads and cam, it's getting a t18, 31" tires and a 3.73 rear end. We've got lots of hills where I live and it will be occasionally towing a small utility trailer or my 1700lb boat package. I prefer bottom end torque and will very rarely hit more than 3krpms. For these reasons I'm thinking the road demon 525 should be adequate. They also make a 625 but I feel like that's too much for my driving. Any input as to which I should choose? Or even avoid both? I'm not going edelbrock though. Not really a fan of them.

 

Other option is the 4100 autolite if I can find a junkyard one. Intake is a factory 4v one that will remain stock until I get bored with the jeep.

 

If you arent drag racing I don't see why the 525 shouldn't be sufficient. Most people tend to over carb an engine. The smaller carb should give excellent throttle response on the mainly stock engine.

 

According to one of the numerous carb size calculators on the internet, you only need 258 CFM to run the 351 at 3000 rpm, and 525 CFM is good for 6100 rpm.

Here's the link:

http://www.carburetion.com/calc.asp

 

the Weind stealth intake would assist with low end grunt as well.

 

How's the offy dual port intake. I picked up a cheap 351 for parts like the brackets, alternator, power steering pump, timing cover... it has an offy intake and edelbrock valve covers on it as well....for 150$

 

For lower rpm power the stock 4V iron intake is best. An aluminum one will save weight however. I don't know the performance of the Offy dual port other than noting the dual port really restricts flow, which might be beneficial to your goal of a lower rpm power band.

 

I may try it. If I find that I don't like it I'll swap out the factory one .