Rebuilding A Doug Nash 4+1 Street 5 Speed

With a buddy's help, and a pair of 6" long guide bolts with the heads cut off, it eventually went in. Turned out the pilot bearing had popped out when we pulled the tranny, and was blocking the shaft from going back in, took us awhile to figure that out, not a lot of access with the blow bell I'm using!

I'm beginning to doubt my mechanic's abilities, the tranny let go yesterday morning, the full power, power shift from 2 to 3 (or was it the 3 to 4 shift?) got really noisy all of a sudden! Shut it down and coasted to the side of the road. A buddy happened to come by with his rollback truck, gave me a quick ride back to my house....
Now I get to pull it out again, should be gettin good at that my now....

Not sure what I'm gonna do with it, I do have a built th400 in a bop case, and I have a 425 flex plate, they are balanced different then the 455 Olds flex plate with a slightly different crank flange bolt pattern, so I could put the th400 in, would require a different length driveshaft. No decision yet....

The DN is rated at 450 ft.lbs, I'm probably giving it a little more then that....

And that's usually the rating for first gear, the higher ratio gears will usually take more, it usually increases as the gear ratio decreases...

And I always figgured my street tires would break loose before the rating got exceeded, a common experience in this car in first and second gear, third would sometimes break loose too, if I was up in rpm and on boost then I shifted, but not so much....

Am also considering a Lenco ST1200...

WEB_Pg_6_ST1200_complete.jpg


Always thought those looked really cool with all those shift levers sticking up out of the floor....
 
The blown Olds 425 is making around 700-800 ft/lbs torque.
Well past 450 mark.
Mopar 883 Hemi Trans will take it.
What Ronnie Sox used in his Pro Stock Hemi Drag Days.
 
I just happen to have a recently built up turbo 400 in a BOP case in the back of the shop.
It's looking better and better every day!
 
The 1965 Olds 425 A engine I have Willy is rated for 470 Ft/lbs stock.
360 Hp.
Makes same power close to a Pontiac 455 in 1970 as my 1970 Poncho 455 I am building too.
The '70 455 makes 500 Ft/lbs stock.
I am positive that Blown Olds 425 of yours is pushing 800 Ft/lbs torque or more.
The Olds 425 Flexplate is special.
Different balance pad location & unique Asemetrical crank bolt pattern.
Its also thin steel
Dick Miller, Joe Mondello, Summit Racing, someone in Ebay is selling the Olds 425 Flexplate in thick SFI version for Race use. I don't recall right now.
It was pricey at arounf $300-450. So I have held off buying it.
Stock Olds 425 factory Flexplates are hard to find.
I got mine off a 1964 Olds 330 ci 4-BBL cop car engine.
Same flexplate. $25 from a friend that runs a junkyard.
Was missing off my '65 425 engine when I bought it.
 
Wow, that suck, i guess you need a stronger trans(nothing to do with mechanics abilities)

Am gonna help you with the trans, just gift it to me :). i need an OD manual and something to do :D.
 
I just have to go back and look at what I did to second gear:
DougNashRebuild008Jan2014.JPG

Other then damage from loose gear teeth getting in the bearings, everything else was good, so it was just plain old brute hp that did this....
It happened so fast this time, that I just don't remember whether I was slammin into 3dr, or into 4th when it let go.
Shut it down and coasted to the side of the road on the clutch immediately, then got a ride home from a buddy who just happened to drive by in his roll back.
And what a coincidence, it's the guy I got the '55 from in the first place, he's watched closely as I turned it into a "gasser", with his approval. He's got a Henry J he wants to do the same with, but just doesn't have the money at the moment to do it....
 
883 Hemi Mopar 4-speed good for 1,000 Hp easy.
1500 HP Shorterm.
Pics coming later today of a 883 Hemi 4-gear.
 
My friend Mopar Bob is expecting his newly purchased 1969 Vintage Hemi 883 4-speed 18-spline input shaft to show up Monday.
We tracked it to our local UPS. Saturday no delivery.
Actually have 2 883's to rebuild.
Standard Fine spine with 2.66 1st gear.
Resell on Fleabay.
Rebuild the 1969 Hemi 883 2.66 1st.
The Hemi Box has real stout Gears. Cut on a low helix.
Thick gear tooth profile. Much stronger than M22 or T56 or any others I have seen apart.
Ignored because its Mopar.
Chevy guys used in 1970's. Muncies kept blowing up.
Only Hemi Box could take it. Real Abuse.
Few more nights get Pics of it the Hemi 883.
 
Sheesh, when it rains it pours,
Had parked the 55 gasser until I could get to it to pull the Doug Nash and take a look at what went out, as I was replacing the water pump on the 502 in my '59 prostreet chevy truck. Finished that and took it out for a "trial run", and the turbo 400 in that rig let go, no forward gears, still have reverse, had to have my wife come tow me home, embarrassing! So I jumped in my remaining rig, a '55 chevy 4x4 pickup, and the steering starts making loud noises when I turn the wheel, had my wife turn the wheel while I checked it out, got something going out in one of the front drive axle hub bearings! So am attacking the th400 in the '59 first, have a buddy who does these, so I can pull it and get it to him. Figure a clutch pack on the forward planetaries went out. Then will attack the 55 truck problem, finally I'll go after the gasser tranny problem!!!
And I'm supposed to be working on a couple of Panhead Harleys too! :roll:
Ooof, my back hurts!
Willy
 
I know the Feeling Willy.
Being overwhelmed with projects.
I just want to work on Race cars for a living.
My stuff at night.
Daily Drivers are just as important as a project or toy.
More so really.
It has snowed & snowed a lot this winter.Just bitter cold.
Wifes car down. Fixing it.
Cant drive the Vette in snow very well.
Suburban K1500 4X4 has been he workhorse.
Pulled at least 10 cars, trucks & SUV'S. stuck in. snow & ditches with the Burban.
Snow again this weekend. 8-12 inches. Cold next week.
Teens again.
 
Well, a shortage of money has pushed me in the direction of just fixing my Doug Nash and just taking it easy for awhile, as it's obvious this gearbox won't take the HP this motor is making.

When I pulled the tranny and opened it up, it wasn't the third gear that had blown, when I hit third gear, the main input shaft drive gear, and the cluster shaft driven gear is what blew:
DougNashRebuild107sMar2014.JPG


Here's a closeup, took these with my cell phone, so this one did not come out very clear, but you get the idea:
DougNashRebuild108sMar2014.JPG


The fact that I shut it down immediately I think saved me from more damage. The front mainshaft bearing is noisy, and the front cluster shaft bearing is also a little noisy, so I'm replacing them. The rest of the gear assembly is fine.

Richmond Gear is sending out a new input shaft and gear, and a new cluster shaft driven gear. Nearly $600 for that, and probably another $100 for the bearings, which I can get locally.

Looked at the new Richmond Gear "Super Street 5 Speed", which they say is rated at 600 hp, mine is rated at 450 hp. Would be fun to try one and see how it holds up, but the quoted price is $4,065 plus shipping! Think I'll wait awhile.

http://www.summitracing.com/parts/rmg-7 ... /chevrolet

It's a mighty fun car to drive, but I can't keep breaking transmissions. Have upgraded the clutch (dual disk McLeod) and the rear end (35 spline 9" Detroit Locker) and the driveshaft with 1350 u-joints, now the tranny is the weak link!
Aloha,
Willy

LINK to tranny repair pages
 
If Richmond Gear offers 9310 Nickle gears it would be helpfull Willy.
Blown Olds 425 is super powerful to say the least.
 
lack of easily disposable funding ,
(that always seems to be needed for bills, rather than toys )
has done far more than anything else to prevent me, from building my dream cars or even repairing the cars I own in many cases than any other factor so I can wholly sympathize
 
I'll rebuild the DN five speed, I wonder what I could get if I sold it? you think they'd be worth $2.5k? The standard RG GM Street Five Speed lists at $3,687 at Summit:
http://www.summitracing.com/parts/rmg-7 ... /overview/
I can attest that this one is in good shape after the rebuild, photos of the insides, etc.
Then put that $$ towards the 600 hp version!
Willy
 
You could try posting the Doug Nash 5 on RACINGJUNK.COM Willy.
I go there sometimes searching for used Drag Race parts & Gasser Era Goodies.
Where I found my 1958 Pontiac Rear Housing.
Everone wants a 9 Inch rear.
I want the 9.3 Pontiac Olds Rears as many as I can get.
Dana 60's too.
Have a nice collection of both building up last few years.
Vintage Homemade Gasser Ladder bars are neat too.
 
A few more pix of the tranny, waiting for parts to arrive:
DougNashRebuild109sMar2014.JPG


DougNashRebuild110sMar2014.JPG


The main drive gear on the input shaft:
DougNashRebuild111sMar2014.JPG
 
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