"I thought the core support needed some extra braces from the firewall, I'll have to find those for her truck."

Listen, I think I gave you the wrong idea on the upper radiator hose design. It is meant to allow the upper hose to flex with engine torque. It was the OEM design.

Your present upper hose looks stressed to me and may fail on the road.

____________________________

I think its just the picture. I really hope it doesn't fail!

First drive went pretty decent, we had an issue with Sniper that we finally got figured out. We took it to a local shop and they pressure washed the chassis really good, unfortunately this washed all the old grease that was making the king pins tight! So we are doing King Pins and a Clutch before we go

Nice Job!

This is really cool with the EFI and the turbocharging!

I will probably want to pick your brain on the EFI! 

I have an MSD "Y" distributor and MSD Atomic TBI going on my 272.  I don't think I would try turbocharging though! 


Cheers,

Rick
in Western Wa.



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1955 F-600/272/E4OD// Disclaimer: No animals were injured while test driving my F-600 except the ones I ran over intentionally!

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This post was created using OpenSuSE Linux x64 and Firefox

Ok,

I have to ask.....

Are you using a double-reservoir (split) master cyl? (looks like it)

And how did you do the brake system with the dual? wheel cylinder brakes you have on the back and the single cyl on the front?
(understanding that yours might be different with mine which does have upper and lower cylinders)  


With my split hydraulically assisted master cyl, I will have to use a proportioning valve so as not to apply too much pressure to the back during braking.
(no power steering, but I have a power steering pump just to provide fluid for the master cyl) 


Regards,


Rick







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1955 F-600/272/E4OD// Disclaimer: No animals were injured while test driving my F-600 except the ones I ran over intentionally!

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This post was created using OpenSuSE Linux x64 and Firefox

Rick,
Are you referring to the hydraulic clutch master cylinder next to the brake master in the first photo?

Howdy,

No.

I am referring to what appears to be a split-system vacuum master cylinder. 

All these medium duty trucks had single system brakes, meaning that a leak anywhere in the system (front or back)  would result in complete loss of brakes.

It wasn't until somewhere in the 60's (67 or 68 maybe?)  they went to a split system like all cars and trucks are nowadays.

The medium duty trucks used a manual split master with 2 separate vacuum boosters where the earlier trucks (including my 55) had a single manual master with an inline vacuum booster.  They worked ok ....but if one wheel cylinder started leaking enough to put the pedal on the floor, there was no brakes at ! 

I for one, do not like the idea of driving a 7000lb (empty) truck around that could lose brakes due to 1 leak.

So I am using a split master from a circa 2000+ Ford Super Duty truck that has 1.5" pistons. (I think my original had a 1.25" piston)  It requires a hydraulic pressure source so I am using a PS pump.

I suppose I could have just used a firewall-mounted vacuum master but I wanted to keep the master cyl under under the floor in it's original position and use the original pedal instead of hanging a pedal in the cab.

Here's what mine looks like: (that's a 272-Y there with a Bentsen transmission adapter and a Ford E4OD out of a 94 F450 diesel)



The only "downside" is that I need a hydraulic pressure source instead of a vacuum source.....hence the PS pump....... And I'll probably need a hole in the floor to get to the reservoir unless I relocate it.

SO I would love to know how it's being done in the 58F600  I'm assuming that I will need to do something with brake pressure proportioning!



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1955 F-600/272/E4OD// Disclaimer: No animals were injured while test driving my F-600 except the ones I ran over intentionally!

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This post was created using OpenSuSE Linux x64 and Firefox

Yes. It's a split system. The truck already had an issue on the rear axle with the single pot system. We knew we were going to hit some serious mountains on the way home and a single point of failure brake system wasn't going to be a good thing.

We bought a "kit" for a '58 F100 that came with a cantilever linkage that step one of the instructions said to throw away and use the generic $35 booster brackets and DIY a booster rod....

There were kits available with a master cylinder, but the biggest was only a 1.125" bore. We used an All Star 1.25" bore master cylinder pn ALL41064.

With 4 corner drum brakes you don't need a prop valve. But installing one won't hurt anything and could be useful for simply adjusting the brakes for drivers preference. We didn't use one, the brakes work fine.

The biggest issue on our truck was the lack of brake parts to get it right to start with. We had to clean the rear shoes and reuse them. They were soaked with brake fluid and grease/oil from a seal failure. They needed relined, but we simply didn't have two weeks to wait for them to get relined. They got steam cleaned, brake cleaned, baked and reinstalled. Every now and then you get a whiff of burnt gear oil, but they worked!

Brake adjustment was a little problematic as well. We played with it adjusting to get just a light drag, the brakes still got better with a pump or two with the pedal.

With the hydraulic clutch, we used a smaller booster (dual 8) instead of the normal 14" style. We've tested this on cars and the larger booster is much more effective. Our brakes are, and feel like, they are under boosted. A hydro boost ran off a power steering pump would be much better and clear the clutch master. But then you need a P/S pump. We've actually removed and avoid hydro boost on cars as they over assist and terrible to drive. There is a reason they are OEM in larger pickups and no used on cars.

Thanks for that info!

I think I will probably have some "over" assist as you say but I think a hydraulic regulator might temper that.  I was worried about having enough fluid volume with any of the master cylinders that had small pistons to actuate the front and back.

The front brakes on my 55 have single cylinder,  SINGLE-Piston actuators.  Only the top of the front shoe is actually  "pushed" forward. (sort of like a boat trailer drum brake system)

The bottom of the front  shoes are hinged together so they all contact the drum when the top of the front shoe is pushed. 

I suspect they changed that in the mid fifties I just don't know when. Are your front wheel cylinders single-piston too?

I think I couldn't find replacement shoes either but a local Brake place in Tacoma (Cascade Friction Materials) was able to reline both front and back shoes nicely and they also turned my drums.

I am very lucky,   none of the drums had ever been turned and all they had to do is take off a few thousandths to clean them up.  The guy told me I would probably never have to find drums for it.  (I don't think they exist anyway!!)

By then, I'll either be unable to drive at all or I'll put a DANA 80 on the back and a much more modern front axle on it with disc all the way around!

I think you said you're using a T98 transmission with a 2-speed axle.  (5.83/8.11?)

Mine is a 6.80:1  axle  but I also have an Eaton 1350  5.83/8.11 too.  I am not sure I'll be using it with the E4OD. 

The E4OD has a 0.71:1 over-drive ratio.  With the 9.00-20's I have on the truck, (roughly 40"  rolling radius)  I figured I would see around 504 rear wheel RPM @ 60MPH.  504 x 6.8 would then be 3428 RPM in direct drive.

With the 0.71 OD in the E4OD (& torque convertor locked) the 60mph RPM should be around 2400 RPM  (2434) maybe that's about right for my 272?

What size tires do you have and what RPM do you see @60 MPH with the 5.83 rear axle?


Using the 5.83 axle, I calculated with 40" tires I would see 2938RPM  in 3rd gear (TC locked) and 2086 in OD. 

That might be too "tall" in the gearing  for my 272 except maybe on a level highway,  empty with a tailwind!!

The 8.25-20 tires are of smaller diameter but Les Schwab told me they couldn't get them anymore.  My only choice was the 9.00-20's

Now if I were to go to 22.5's or 19.5's I suppose it would be better but when I got my current set of 20" 5--lug lock-ring wheels no one was offering 19.5 or 22.5 wheels.

I think you have more choices in 6-lug wheels.






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1955 F-600/272/E4OD// Disclaimer: No animals were injured while test driving my F-600 except the ones I ran over intentionally!

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This post was created using OpenSuSE Linux x64 and Firefox

Brakes sound the same design as our truck. Primary and secondary shoe up front running off a "single servo" wheel cylinder. Hot tip, they don't work in reverse!

Our rears have dual, "single servo" style wheel cylinders that are very similar to the fronts.

I'd fight to the death to keep the 2 speed rear lol. Especially in the mountains, starting in 1st/hi, then having the ability to simply lift to downshift was a huge help when really pulling. Also helpful rolling over a crest to simply lift/stab down shift for engine braking.

All of your gearing math looks reasonable to what we saw. 2500ish is 48-49mph in 4th/hi. 3100ish was 58-60mph.

Les Schwab told me the same thing but I found a set of NuTec Super Traction rears and had them shipped right to Les Schwab. I'm glad I did, we really used them on the way home. They offered a different NuTec tie but it was the cheesy zig zag military cheapo pattern.

They also tried to tell me they couldn't balance lock ring wheels and bias ply tube tires, so I convinced them to try and prove they were right lol. They were very rough before balance and reasonably smooth after wards, which they assured me wouldn't last. 3,000 miles later including over 1,000 miles on dirt gravel, they are the same. Very acceptable.

I don't see a stock NA 272 pulling overdrive with a locked converter at 60mph. I guess it would depend on the local terrain. Tacoma isn't too far from flat, but there is hills in every direction!

We're from Moses Lake originally! Great place to be "from" haha.

Here's the exact tires we got. I love them. They run smooth as well. They are the old FireStone Super Traction molds that were sold to Power King, then NuTec and now sold as NuTec N300. Les Schwab could only get the N200 even though they carry NuTec.

https://www.ebay.com/itm/335497545134?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=5czKIfszRZW&sssrc=4429486&ssuid=G9JJtUK_RLe&var=&widget_ver=artemis&media=COPY