The Stovebolt Site Forums The Parking Lot Big Bolts 1972 c50 sbc 350 m465 single speed rear.....

There are online tire speed conversion calculators.
Plug in rear ratios, tire diameter. Jeffrey

It kind of sounds like your engine either needs a tune up or it is completely worn out. Besides a good radiator, you need to get the thing to put out its rated HP before you start worrying about bigger tires and faster gears. If you slow your engine down more, it will become even more of a dog.

Well I don't think she is worn out I jus rebuild engine and it runs way better then it did before... it was leaking oil all over the place and roasted clutch plate due to oil absorption so had to drop trans and at that point I was like might as well pull engine too and resealed entire thing put new piston rings on and few other things so she has great compression now and no oil leaks and will pull 20000lbs up hill all day jus not very fast but it has great low end power, jus when I get on the highway I become the parade leader cuz " I can't drive, 55" haha..... I thought 2 speeds you could basically have my ratio now as the low end side and then have high end side ratio for once you get the ball rolling good you can keep it rolling good(highway speed) but if I'm wrong about that plz sumone inform me why and possibly how to accomplish more speed without losing low end power

Most 2-speed rears are set up for low and lower ratios. Sometimes you can get lucky and find a rear with the high side higher than your current single speed ratio. I had a 7.17 in my fire truck and found a 6.14/8.36 2-speed that fit in my housing making it an easy swap. It works out great as I still have low gears when I need them.

Find your local big truck junk yard and start asking questions...you might get lucky.

Mike B

So would a 2 speed with 6.14/8.36 ratio be what I want for the lower end power and a lil higher end then what I have now? I jus don't wanna go out and get 2 speed rear if I'm not gonna get a lil more top end speed cuz rear ends arnt cheap I did find a sweet spot that's been collecting medium duty truck since the 70s or 80s so they have quite the selection jus a lil pricey....and also been finding old farmers scraping grain trucks wit 2 speeds so I can find sum for scrap price (25cent/lb)at recycling center and that's probably where I'm gonna get one from I got a c60 front axle that I was thinking about swapping under my c50 it's heavier duty has 10bolt hub and bigger brakes being the main reason for wanting to swap cuz if I'm planning to go faster loaded probably be good idea to be able to stop faster also lol any input on this front axle swap out?

it is just math. I believe earlier in this thread you stated your rear end ratio was 7.20. If that is the case, and you put a 2 speed with a high ratio of 6.14, you will gain some top end speed and still have all the low end you want with the lower low ratio. I believe Mike B did some math for you earlier in this thread. Please re-read it.

I should have mentioned my 2-speed rear swap (6.14/8.36) was on a Eaton rear, not a GM rear like you have. The Eaton rears have a better selection of gear ratios.

Is your 350 sbc a car or truck engine? Do you know what HP the engine is? Do you have a governor on it?

With 9.00x20 rear tires at 40" tall, 7.20 rear gear ratio and 3700 rpm you should be doing about 61 mph...sound like you need to wind that small block up and go! Your governor (if you have one) is most likely set at 4000 rpm. If 53 mph is all the engine will do (confirmed with GPS), you need to revisit the engine for lack of power issues.

Mike B

How can you tell if it is a car or truck sb350? No clue on hp...and I might seem like a scrub for this but what is the governor and where is it located I've heard the term jus was always clueless and never had an urge to ask about it lol

I'm not a complete scrub tho.... I did pull the engine and trans to reseal engine before reclutching her due to oil leaking everywhere lol so I have had it all apart but do not recall governor didn't do to much to trans as it was working fine and not leaking but I did clean it up and paint it also

Hy DIY.MechanicMike, if your engine has a governor it will be mounted under your carburetor, there will be vacuum lines going to it from the lower area of the distributor, hope that helps.

Ok so I was thinking that was carb related cuz I was jus doing sum carb tweaking on my f600 bucket truck and found out I had the holly 4412 race carb and ended up not being able to tune it right so I bought a new carb the 7448 holly and she runs alot better no more back firing but I think there might be a governor on my Rochester 2bbl that's on the c50 it kinda looms like a funnel turned sideways with vacuum line going to dizzy so I'm guessing that's a vacuum advance of sum sort???

So I did mess with truck a little today checked the timing and it appeared to be off a tad and adjusted to what I believe to be correct or atleast it seems good by the sound of idle but had timing light on it and it hits about 10° before and I drove it a bit and realized my fuel pump is leaking fuel so guessing it's expiration date is here it was jus dripping slow nothing real crazy but could smell gas pretty strong when I shut it off and noticed the drips under I try to look for drips every here and there on all my vehicles.... but since the governor thing was brought up it had me thinking while I was driving it and I noticed jus revving the engine up it doesn't even let me rev it past 3200 ish rpms according to my after market setup is there sum sort of adjustment on that or is there sum other hold back cuz I really wanted to try 60 at 4000rpm but nope just won't but I did hit 60 in neutral thanks to hills haha and I feel if I could hit 4000rpm at bottom of a hill I could pull up it faster when loaded jus with the momentum

I also have finally gathered all the parts to get power steering in the rig also.... jus gonna clean everything up nicer maybe paint it but I was informed by a older guy there was alot of experimenting with steering around that time he said there was manual steering, power steering,and powersteering inline with assisted steering via (hydraulic cylinder) the assisted steering seems like overkill but I guess for certain applications it would be nice any one have any input on the assisted style?

The Power Assist type uses a special Drag Link with an integral hydraulic control valve that controls a hydraulic cylinder that's connected on one end to the frame/crossmember and to the tie rod with the other end. As the drag link is pushed or pulled by the steering pitman arm the cylinder assists the driver in pushing or pulling the tie rod. This system was used in everything in the late 50's and 60's. and does a decent job. That said, it doesn't compare to todays power rack and pinion.

Mike B

Icic I know we have a massey ferguson tractor with the steering assist and jus got new pump and made a huge difference in steering but got a question... I have manual steering now I'm upgrading to the power steering gear box with 2 ports on top and two on bottom which I was told can go to the assist cylinder or jus looped which I was gonna hook up a fluid cooler inline for the loop... By doing this will my steering improve a bit from the manual setup I have now

Icic I know we have a massey ferguson tractor with the steering assist and jus got new pump and made a huge difference in steering but got a question... I have manual steering now I'm upgrading to the power steering gear box with 2 ports on top and two on bottom which I was told can go to the assist cylinder or jus looped which I was gonna hook up a fluid cooler inline for the loop... By doing this will my steering improve a bit from the manual setup I have now