Technical 4-71 Score, School Me on blowers

I’ve done some research, but school me on what I have and what I still need.
I’ve known about these parts for a few years and my friend finally wanted to let them go. I’ve been focused on my 60 ElCo but have a 283 powered ‘35 3 window that’s been on the back burner. This 4-71 is perfect for it.
I think this is a “later” Weiand 7135 SBC manifold because the logo is smaller lettered. There are the two dual quad adapters, one older, the Cragar snout, and the blower. I think the blower is basically stock GMC and someone started polishing it.
How do I tell if the blower has been set up for gas hotrod use?
Any idea on the vintage of the intake?
I think I need a drive setup including the snout arm, the shaft for the snout, a back plate, a triangle plate, and whatever internal stuff the blower needs. What else?
The plan for the car has been a ‘58 283, ‘60 T10, and a 9”. I’ve got 327s around, but I wanted to focus on a late 50’s kinda build. Would this blower be happier on a 327 or a 283?
V belt drives are super cool, but the gilmer drive belt whine is great too. I guess I need to make a decision there…
This is a long term kinda project so I’m not in a hurry for the missing parts. I’m focused on the ElCo but when stuff like this turns up you’ve got to grab it!

Pics:

 

nice!

since it still has the "lip" on the base, it's pretty likely that it was never converted.

 

Guess we don’t have to summon Squirrel to the HELP desk.

 

YET.

 

Nice score! Perfect for a SBC. The blower will not care what's it's sitting on. Just do some homework and pull together a collection of parts that will play nice together for the street application. Nothing radical required. Moderate static CR, choose your pistons carefully, and don't get carried with drive ratio. Pumping air generates heat. Depending on your background, patience, and tooling it's not beyond a DYI conversion. But also lots of places to send it out.

 

That mounting lip is the first thing I always seem to notice on original GMC blowers.
I had my nose in lots of magazines starting in my teens, often wondered what the lip was for, then an older brother of a grade school pal of mine said it was to support the weight while installing them because they were mounted on the side of GMC diesel engines.
Another thing I will never forget was him saying that when he was in the Navy in the mid 60's they dumped A BUNCH of 6:71's in San Diego Bay, something about surplus and such.

 

The more I look at it, the more I think it’s stock.

I’m have a can do attitude and good tools including a mill. Unfortunately the garage the mill is in has no power. My projects have projects. I’m on the fence about sending it out, luckily I have time to decide. There’s a guy on YouTube who goes through everything on a 6-71, and it looks approachable, just involved.

The mounting lip hits my valve cover. The blower won’t sit flat on the intake. I need to prune it. When my grandpa was in the Air Force, he saw tons of usable stuff get bulldozed into the ocean in Hawaii. He never talked about superchargers though.

I had to test fit!



I should set some carbs on it too.

 

I seem to remember an article in an old Hot Rod magazine about converting those blowers, don’t know what year. Anyway, it showed the lip being removed using a bandsaw, carefully running the blade just next to the overhang. No machining required. Again time for squirrel to chime in…

 

If its just compressing air, how does it know if its on a diesel or a gas motor, and why would it care?
Never had one, didn't know they had to be "set up" for gas. Thanks for the education. Correction, air /fuel mix, but again whats the difference?

 

Think about the RPM it works at, and the pressure. Different clearances, mainly.

 

If you really want to impress the traditional crowd and you have the tools you can really "prune" the blower case like Tom Beatty did starting in the fifties.





Good read
Here:
https://www.jalopyjournal.com/forum/threads/how-is-a-pruned-blower-case-mounted.999144/



Here:
https://www.jalopyjournal.com/forum/threads/holy-grail-find-tom-beatty-blown-olds.1155299/

 

Cool score! Looks like a fun project.

 

not something he wants to consider with the intake he has, though!

 

You did not mention a price,
The value is really in the intake
Crager Snout , carb adapters,
The 4:71 to convert No big deal
Mill / Lathe make it easier but really not needed , Unless you trying to build set up as stage 2 plus ,
5-7 psi 283 -327 5,500 ish.
Mark gears & rotors @ tear down.
Cut or file Lip off .
Main thing ,seals .
Bearings ,,, I have used stock on spinning 5,000 engine Rpms ,
There are charts / formulas for rotor RPMS . Then translate to bearing speed.
Modify stock rear end plate ,
Plug oil drain holes ,
Out side thinking to make a snout axle
2 used pulleys $50 each , new $100ish
Belt , $50 -100
Idler make or buy , $150- 400
Off top of head ,can not remember
Diesel rotor clearances , gas around
.006 .
Long straight edge with sandpaper complete even stroke to knock Rotors
Down , if to loos , Just will need to spin little harder

 

If you are on the fence about doing the blower conversion yourself or sending it out this would be my recommendation. First, buy a copy of the Detroit Diesel in line 71 service manual. They are on Ebay all the time. Just watch the pricing as I have seen them from $15 to $75. Why? Because it will show you much more detailed steps, tools, and how to info on disassembling and assembling than the typical street conversion books provide. You will want a street conversion book after you decide to proceed on your own. One of the best is the 1984 Street Supercharging by Pat Gannal. But most of them will get you by.
You don't need most of the OEM Kent Moore tooling, but by knowing what it looks like and used it's easier to come up with a substitute. The detailed info on setting rotor clearances will save you time and frustration should you decide to DYI. The only critical tooling is a set of pullers, modified or made, so you can remove both helical rotor drive gears at the same time. If you don't you will damage the gears. Remember, this is 1930s technology, not rocket science. My first job after tech school in the early '70s was at a Detroit Diesel Allison dealership.

 

good call!

 

Hello,
We were thinking about superchargers on an SBC motor when we started our build. at first it was the centrifugal Paxton style superchargers. then we were looking into the 471 version of the GMC diesel superchargers. The hot rod/drag race equipment folks had already constructed the combination of a blower manifold for the 471 to the SBC. so, all we had to do was get a 471 blower.

There were tons of diesel shops near our house as we lived near "Truck Central" in Wilmington and the Long Beach/Los Angeles Harbor docks. When we walked into any of the shops, they each had a display of the latest in Roots style blowers from GMC. So, we were in Blower heaven.

We finally found a new 671 blower that was bolted to a diesel motor display, but the owner of the shop wanted to sell it alone. Why? He was going to get a new fully polished new version for his display model and wanted sell the natural finish version. Right up our alley... so to speak. But, he also said that the 671 was far superior to the 471. he had no idea where we were going to use the 671, so his comment was from the years of experience of superchargers.

So, my brother and I bought the 671 directly off of the showroom display and got a great sales price if we took it that day. Now, we were the owners of the 671 new supercharger. Clean, stock and a complete unit that we took to Reath Automotive for re-construction for drag racing purposes. (No other speed shop was doing supercharger modifications at the time) The diesel shop owner said we could use it as it was in new condition. But, for drag racing, we needed expert tooling and machining from a shop that did most of the work on plenty of drag racing blowers of all kinds.

Jnaki
that supercharger was a part of our new products we had just received from Los Angeles. A new Isky-Gilmer Belt Drive Kit and Edlebrock Manifold for installation on an SBC motor. It was the second unit that was yet to be sold at speed shops all over. The Edlebrock manifold was the only manifold for the new 671 to the SBC motor. That was the way the new kit would be sold later on when they were in the speed shops. This was in February of 1960.

(The Isky Shop had unit #1 of this kit)

Here is the complete story for superchargers that I wrote for posting several months ago.

I would not mess around with your manifold and supercharger. Leave it stock and no trimming. Weight gain is minimal and the blower strength is in the design from the factory. (Plus, why make yourself have to go under the blower to remove it. The stock application is a simple removal of supplied nuts and the blower comes right off) Check out these two So Cal supercharger shops. Their expertise is top notch and service is also top quality.

Note:
Hello,

In So Cal, there are two of the best supercharger shops within freeway close to just about anyone in the area. If we were going back to having a supercharger on our motor for a hot rod build, It would be hard pressed not going to one or the other. Hampton Blowers and Littlefield Superchargers.

We have known about Don Hampton since his early drag racing days at Lion’s Dragstrip and his vast history with a ton of competition race car builds. As a drag racing record holder and a true icon in So Cal drag racing, he is very well known in the history of drag racing. Since his Hampton Blower business took off, his shop is well known to put out a variety of models for all kinds of motors and street/or

Don Hampton was one of the early drag racers that drove just about any race car in existence. From modified Competition Coupes to FED race cars. He is well known and has a cool history in So Cal drag racing competition. He even has a glass enclosed case with memorabilia about So Cal at the Lion’s Dragstrip Museum.

As far as a used blower, the big questions are, how much has been done to it and how long has it been in that condition. For something as important that pushes the limits of any motor, why would you want to take the chance of a used blower? The stress of any motor racing is always high. Add in a supercharger to a blower-spec motor and the power and strain has increased 10 fold. So, a used blower is always in question.

We would trade it in for a new one from Hampton Superchargers or Littlefield Blowers Those two supercharger places are well known in So Cal and have ties to our drag racing background history.
https://www.jalopyjournal.com/forum/threads/early-drag-racing-photos.1222399/page-100#post-14933307

The other source in So Cal is Littlefield Blowers.


Mert Littlefield was in my graduating class at Long Beach Poly High School. He was also in 2 years of Metal Shop and Auto Shop during our last two years of school. He was a skilled mechanical person that could lay a bead of oxy/acetylene and when it was time for us to learn “arc” welding, he was the best in the class. I could not see out of the dark flip down face mask, so my beads were wanderers. Ha! The oxy/acetylene glasses were less dark and I could get a great looking bead on my welding. But, his beads in both were top quality machine shop, professional work.

But, after our drag racing era, Mert Littlefield went into drag racing with a flourish. Besides Don Hampton Blowers, Mert Littlefield developed his skills and became a builder, racer and specialist in the industry. He is now gone, but before he left us, his company, Littlefield Blowers is still going strong with the skill and knowledge from the history in So Cal. (racing and street applications)
https://www.littlefieldblowers.com/
1-714-9929292

Jnaki

This was an old story I wrote about the supercharging about my old friend, Mert Littlefield.

Every time I see a Littlefield decal or photo, my mind wanders back to the teenage years at our old high school in Long Beach. The local area had produced a ton of people involved in all sorts of drag racing history. Some had early hot rod/drag racing history already in place. Others got involved and over time, became part of that history themselves. Mert Littlefield was one of those people.

I would see Mert at school almost every day as we had classes together. But, what we learned in those early, practical technology classes helped us develop in different ways. His practical skills were at the top of our technology classes and we all respected that. But, his friendly demeanor was always nice to be around when he was doing his class projects. It was never a secret way to get a better grade. He always helped others do better in all forms of auto mechanics and in the metal shop classes.
His machining skills were top notch and we usually watched how he did his projects. After high school, we drifted apart until our drag racing adventures were over and his was just beginning to get some notoriety. Those articles about his skills and builds were always impressive as the years rolled on for all of us. He is gone now, but his work skills, designs, and supercharger business is still going strong in So Cal.

Mert Littlefield was in several of my high school classes, besides the tech classes. We were in the Autoshop, Metal Shop and others that don’t stand out as well as the mechanical tech classes. We both like hot rods and drag racing. He was someone with a lot of hot rod skills, but, was for me, a quiet person that was a friend to everyone. His welding skills made mine look like a beginner, until I kept at it so I could get a good bead for strength. But, welding was not for me in the future, as I could not see what I was doing, using the standard dark protection shield glasses.

As all sorts of friends come and go during the years of high school. We were all impressed that many years later, he became well known in the field of drag racing and supercharging. His history in hot rods and funny cars started it for him. We did not see him during our foray into stock car racing with the Impala or the 1940 671 SBC Willys, B/Gas & C/Gas racing days. But, when looking at editions of Drag News, the OC papers, or the various magazines later on in life, his name popped up frequently.

Maybe had he started his drag racing career a bit earlier, or in our next phase, if there was going to be a next phase back then, a cool Littlefield Supercharger would have played a big part in our future build.

Thanks, M...

Note 2:

So, don’t wait, contact one or the other of the shops to see what they recommend and can service. YRMV

 

Or download a copy here for free:

Detroit Diesel - Series Inline 71 - Service Manual - 6SE177 - 1984 - OCR - 913 pages.pdf

 

I’ll probably mill mine. I actually have better mill access than bandsaw access, which is weird.

Those are super cool, but this Weiand manifold is a big reason I bought this setup now, so I’m gunna use it!

I’m pretty excited! It came out of Polson. I’m not sure where my buddy got it before that. He’d had it a few years.

I’m so excited about the intake. The various adapters that people make never look right to me, so I’d been watching for one to turn up.

Thanks for the info. I think I paid a fair friend price. I didn’t beat him up, he could have made more on the auction site. We’re both happy.

I hit the auction site and found ratty versions of both books. I think I’m $30 all in!

Those look super helpful!

Thanks for the info!

Sweet!

 

Anyone know anything about Cragar blower part numbers and dimensions? I want to make sure this snout works for my application. 240-2.

 

I have a snout that length on my small block in a 32 coupe. Works perfect.

 

Sweet.

 

Are you going to Make or buy Parts ?
Or both , Its simple if you have a understanding Of parts ,
A Lathe more likely is needed , to fit whats needed.
Crager , I do not know if they made own part , contracted out, or sold
There wrights to another ,
I have not hand hands on Crager
Since early 80s

You will need a coupler on rotor gear ,
Bearing Od to press in snout , usually held in place with clip ,
Then you have OD size of axle to
ID of bearing ,
Look's you will need 10 inch axle ,
There @ least 1-1/2 to 2.00 that slides into Rotor coupler,
You can extend the pulley Flang out from end .
Then bolts pattern for pulley ( Flang)
Some areveven on all six , then there is
Industrial witch is Not ,
Some have Both patterns
Some are custom patterns . One off's .

A new snout / coupler is around
$600 , but over Years there different
Splines , Axle sizes ,

bearing , there are different spec for loads , speeds , sealed , Non ,
single rollers , double roller

 

Somehow I missed the notification on this reply, sorry! This is all really helpful. I’ve looked at a bunch of pics of currently available snouts but haven’t seen one in person or disassembled pics yet. I’m guessing the driveshaft is either press fit or circlipped into the snout bearing that is circlipped into the snout? And the whole snout/driveshaft slip fits into the coupler that is bolted to the gears?
My Cragar snout looks like it’s bored for two bearings, a circlip, and a seal. I’ve seen old catalog pics that suggest the driveshaft for the V belt pulley is a straight shaft with a flange for the drive gear end and a taper with a threaded end for the pulley. Is that right? When the Cragar snouts were Gilmer drive, did they use the same or setup or the current style I’m seeing now?

I own a mill and a lathe, but they’re in a garage with no electrical service. I’ve got access at work too, plus a pretty good vendor network, aside from someone who can do splines and broaching. If I can figure out how this early Cragar stuff fits together, I can make some parts.
I’m going to comb through McMaster and Motion Industries catalogues and see about belts, pulleys, and such too, just to see what’s out there in industrial part world.

I found an old post of yours form 2011? where you had a complete 4-71 v belt Cragar setup. Is that still around? Just some basic measurements would be super helpful so I can visualize things. This is all going in a 35 3 window, and the angled radiator makes space tight. I’m hoping I won’t have to cut my firewall and move my engine back.

Thanks!

 

Yes. I have a multi belt setup on my 32, 5 window, and a gilmore 2 inch belt on my 32, 3 window. Let me know what measurement you need.

 

@lewk

This will give you some Ideals on how it put together,
There few styles coupler ,fine splines , corse , custom
Pics might help & video


clip












Coupler





Coupler








Axle






Video

 

If space is the problem, and you are running an open wheel car, You can move the radiator forward slightly as long as you move the front wheels forward the same amount to make it look right. Talking a bout 2 or so inches. It can be done on a fendered car also, but requires a little more work by moving the fenders and running board forward and making an extension at the back of the running board to fill the space. Many of these cars have owners who shorten the front frame horns. If you move things forward (within reason), your frame horns will look shortened.

Here's a 32 Ford that's stretched. I saw it at the SRN last year. Looks good and most people wouldn't notice. I think it actually looks better than a stock 32 which can look a little stubby sometimes.


I think the guy said this was a 4" stretch.

 

You have some Great bits...
The Most important take from the blower book, Buy the most expensive valve locks You can find, Lathe turned...
Won't allow a valve to drop..
Ask me how I know )

 

I was able to get a 3 inch 8mm in my
Duce In stock location with Walker Z
For Fenders , Hood ,Fire Wall stock location , Its all tight , to get Top Pulley
Off I have to take off the Rad to fire wall rods & tilt the Rad forward on springs , this is 6:71 with short drive & I use the Waterpump idler bracket & I think my
E -Fan was for a Ferrari ,
That fan pulls close to 50 amps .
On all my blowers I use 8 mm
From Vortec off 90s fox , then B&M 144 to 6,8, 10 ,, My 12 I use 14mm
I do not have a 3 or 4