How will an F-head do with this set-up?

yes, its my 66, i'm not sure with size drums they are but theyr alot smaller then what the 74 has and the 74 is only a yard toy so it doesnt need good brakes

 

I'd be careful saying anything doesn't need good brakes.

The 74 probably has the 11inch drums, very nice.

 

No problem doing that--as long as it is a 6% downhill. Your top speed with 33's will probably be less than 29,30, 31's no matter which gears you use. Just plain too much tire for a F head. If you really want 33's or something bigger, you will need an engine swap and then the cascade begins, including a transmission swap along with the axles and driveshafts.

If it was mine, I would keep the tires to 31's or less and just enjoy it for what it is. Save the mods for when you get sufficient income to do it right or at that point sell it and buy something already set up the way you want it which is usually more cost effective than doing the conversion yourself as long as BUBBA didn't do the work.

 

What is the gearing in the '74? You might just want to switch axles between the two. And maybe the TC, because the rear will be centered.

 

Havnt looked, been interested in that myself though

 

i know the amc 6 wolnt fit so thats out of the question and the 74's tub is shot...

 

Here's my two cents: keep it stock.

I know, I have a highly modified trail rig, BUT I do love wheeling my completely stock '49 3A with vintage 29 x 10.5 mud tires. Way much more fun and enjoyable. I'm not much older than you either. And going fast in one of these things is not fun at all. I can barely do 55 with my restored '53 with an OD. Sometimes, it is more fun to slow down and enjoy the drive once and a while.

 

K.I.S.S. principle rebuild everything then plan for upgrades or plan your upgrades around your rebuilds your old cj5 is an awesome rig just the way it came from the factory and as others have said will hold its own. you seem to be boucing around and dont have an "end " in sight what do you want it to be. then plan backwards from there. as in what do you want? , what do you have? steps in between to reach your goal

 

O.K. I have to add my $0.02 - I was running 36 x 12.50 15's on my 1968 Jeep with the F-134, Pertronix, and a Weber K553 conversion - 5.38 gear and Husky O/D - the problems I encountered were: Not enough power to spin the 36's in the mud - at all.... I had to wheel in low range - first gear - all the time... sometimes kicked in the overdrive, but the F-head just doesn't have the poop to pull the big tires.... On the highway, I had to keep it in 3rd with my foot on the floor and flat ground to maintain 50 mph..... if I kicked in the O/D, the jeep would loose speed immediately.
Now that I have thought it over (for 4 years....) I am switching to 33's, and I have started on the rebuild of the motor - including the Clifford reground camshaft, and shaving the cylinder head 0.060" hopefully it will make for a much more enjoyable driving experience.....
Also with the 36's, it was kinda tippy - especially up and down hills.....

 

I'm more surprised that your clutch is still intact.

 

Let me know how you make out with the 33's, i wolnt be buying my tires for another year most likely, i just passed my test for my permit and it will be not until next year that i can drive without an adult so my jeep will remain in our yard getting other stuff for the time being.

 

Absolutely no issues regarding the clutch - I went with the "big" 9 inch when I assembled it - I make a consious effort to keep my foot off of the clutch pedal when I am driving, and with less than 60 horsepower on tap, I haven't smoked it once..... maybe just lucky??

 

I know it is a few weeks old but I have been given this a lot of thought and here is my two cents.

Consider this - A Suzuki Samurai has a 1.6l engine with 66hp and 79 torque. The have 3.73 gears and almost the same drag coefficent. In fact they are engineered using the original jeeps design specs. I owned a 1991 fuel injected model from brand new and it would easily hit 100 mph. That was stock tires. I later swapped to 235/75's and the top end went all the way down to about 80 mph. With wind or a hill that top speed was near 70 mph

I know people who put 33's on them and all their top speeds went down to around 70 mph on flat ground

So it is not wind resistance but a combination of hp and unsprung weight.

Now all that is about a Suzuki but the math still applies - I think the Jeep would suffer dramatically on 33's with that high of gears. The CJ I have now had 33's, stock 5.38 gears and the f engine and where it is fine at low speeds it has no top end. We are talking maybe 45. Just buy putting the 235/75's on it the top speed is closer to 50-55 mph.

 

I'm gonna stick with the 5.38 gears, run 33's and get an OD unit when i can afford one, i'll be towing it for long distances anyway