[Greg Reid]

I've got a '65 tripower that I'm getting ready for use.. I'm totally inexperienced with them.
The front carb's top and venturi cluster are trashed. I think I can save the bowl and the base but they are rough. The main and rear carbs look good, from the outside at least. I just started with the trashed one since it's the worst.
pontiactripower.com has all parts but I'm wondering how the repop parts are or if I should shop original.

Also, what other rochester 2bbl carbs would work for those parts?

[tom s]

Dick on this site can help you with ever you need.Also Mike Wasson if he is busy.Some of the stuff is really good and some not so much.They wont lead you astray.Tom

[Greg Reid]

I've never dealt with Dick but know he is well respected on the subject. Years ago, I talked to Mike when I was buying this setup.In fact, that's his link posted above. Good suggestion, I'll contact one or both.
Especially interested in other 2G carbs that might make good donors.

[tom s]

There are good tops and bases avail now to repair 2GCs.Tom

[Greg Reid]

I'm definitely going to get a top from Mike Wasson...the reason I hesitated on the base is because of what I read on his site. He suggests his rebuild service for the base over the repop...and the repop is a bit cheaper than the rebuild. Makes me think that they are usable but maybe not totally up to snuff.
Talking to him or Dick makes the most sense. I think I'll go through all three carbs and make a list of what I need to talk about for each one. Top and venturi on the front one are definitely beyond repair.

[Dick Boneske]

For the venturi cluster, you'll need to get a used one--no repros available. I have some if you need.

The repro tops are very good. The only way to identify them from originals is that the front portion of the air cleaner web is thinner than the original. You may have heard that the "GM" is upside down on the repros---it is also upside down on many of the original airhorns.

Regarding the base, I have run across very few OEM bases that can't be rebuilt. I prefer them over the repros, but the repros are very good.

If I can help you with parts or rebuild/coloring/plating, let me know.

Here is a picture of a setup I'm restoring now.


Dick

[Greg Reid]

Thanks Dick. I do need the venturi for sure. I got the bowl pretty well cleaned up and I think I can do the same for the base. My concern there is that I'll probably need to remove the staked screws to really get it cleaned up so I may need a few of those.
I'm going to pm you.

[JC455]

www.VintageSpeed.com
New from Vintage Speed–GTO pontiac Alum. Bases We now have new alum. bases for the big base rochester tri power end- carbs. Bases come assembled with new shafts and precision lapped brass throttle plates and are ready to install. NOTE–no stock cast iron base seals like these. Exact reproduction of the factory part except in aluminum. Fits Pontiac from ’59 up thru ’66 and the ’66 442 Olds. Bases offered in black for stock applications, cast alum, polished alum, or painted finishes for hot rods. It will accept all stock GM parts as well as our new Shafts, springs and hardware and is one third the weight of an original. Modern CNC machines and heat treated alum alloys makes our base parts fit and seal far better than any of the original GM. The large bases are also be offered as a kit with linkage and overhaul kits for original tri power carbs and to retro fit stock gm primary carbs. We offer the reproduction tri power carb tops for this conversion. Base pairs come with the short pump drive on the front base and the long curved arm on the rear basei for all the Pontiacs. (note—on the 442 Olds the long arm is used on the front carb.—same part –just reversed.) Note-You want to nostalia race?? I now have a small block chev. tri power intake that takes the big base rochester carbs—Up to 1500CFM for use on a big cubic inch sb chevy. You better have a BAD MOUSE MOTOR to run this setup. Prices for the alum big base complete ready to install is $ 119.00——-in stock now and ready to ship (patent pending)

[Greg Reid]

Thanks John. Good info.

[JC455]

My pleasure! I was hunting for this info for quite a while- I remembered reading something about repopped aluminum bases, but couldn't find it. I stumbled upon it on the HAMB board and wanted to make sure PY's had the info.
If you order these before I do, please post up a carb build, and maybe a review of your impression of the bases.

[Greg Reid]

I actually found that I had an entire box of spare parts that I had totally forgotten about. I think I'm ok on the bases now but I do need an end carb top.
Photos of the box of stuff I found... I have two good carbs on the intake, one pulled off for rebuild that needs help AND this box of stuff. Unfortunately, not a good end carb top in the batch.

[Greg Reid]

By the way, does anyone recognize the application for the complete center carb pictured in the second photo?
Note that it has an external vent activated by the throttle arm Also, there is a 'plunger' with a light spring on the backside of the bowl. Notice also the large fuel inlet boss on the pass side in front of the choke housing.
Also, just for everyone's information, more parts here- www.pontiactripower.com

[Tom Vaught]

Hard to tell from the picture but the Lever on the pump arm looks like it MIGHT be close to the typical one for a Vacuum or Mechanical Tri-Power set-up as does the large inlet bowl except that a 66 tri-power center carb fuel fitting faces forward.

Tom V.

[Greg Reid]

I haven't found a photo of one just like it but the closest I've seen were some Chevy 2bbl applications. Haven't found one yet that had the 'plunger' looking deal beneath the airhorn

Here's a couple of photos of what I'm talking about. Apparently a vent of some type. The reed is stamped 'TRUEFLEX'.

[mgarblik]

That's a hot idle compensater, generally used on AT applications, especially with AC. Bleeds a small amount of air into the mixture when engine is really hot at idle, to improve idle quality. Some were in the main body near the venturi cluster, some in the location pictured. Not sure what the application is. I would bet Carb King or Cliff would know.

[carbking]

Generally, the problem which causes many airhorns to be discarded is the "spider" for the air cleaner stud is badly warped or even broken from severe overtightening of the air cleaner. THESE ARE REPAIRABLE! To repair:

(1) Acquire another "donor" carb with the same size and shape "spider"
(2) Remove the damaged spider
(3) Using a mill, remove the entire donor airhorn from its spider
(4) Fit the donor spider into the original airhorn, and secure with clamps.
(5) From outside the airhorn, drill through the airhorn into the legs of the spider, tap for a 4 x 40 thread. Countersink the outside of the holes on the airhorn.
(6) Insert 4 x 40 flathead or oval head steel screws, with a drop of red Loctite on the thread, securing the donor spider to the airhorn.
(7) Remove the clamps.
(8) FAR superior to any repro tops I have seen (although I will certainly admit to not seeing them all).

Now if the airhorn is split where the fuel inlet screws into it, because some bonehead put Teflon tape on the brass fitting (Teflon is a wonderful lubricant), then yes, one looks for another carb.

I'm with Dick on the repro bases, I have seen virtually no original bases that could not be repaired. If I were going to even think about considering a repro base, it would have to be cast iron. The Stromberg WW carb has one major issue, an aluminum base. Requires bushing at about 50k miles. One of the major issues with the Rochester Q-Jet is the aluminum base. Has anyone ever seen a thread on here about installing bushings in a Q-Jet base? Holley got away with aluminum bases with Teflon strip bushings. Carter got away with aluminum bases because there is more than an inch of base in the area of the throttle shaft. The 2G has what, 3/8 of an inch? Also, to minimize throttle body wear, both the Stromberg WW and the Q-Jet used aluminum throttle plates, so as to not wear into the aluminum bases.

Most of you know I no longer restore carbs, so the above is not an advertisement, rather just sharing how original parts may be saved.

And mgarblik is correct about the hot idle compensator.

Jon.

[Greg Reid]

That's great info Jon. The 'spider' is broken on the end carb. Unfortunately the airhorn is also 'out of round' and the breather won't fit on it any more. The exact same condition is true of the spare end carb in my box or parts as well. Broken and out of round. Also unfortunately, donor Rochester carbs don't grow on trees anymore..even 2bbls so I suspect that I will be ordering one. Hey, one out of three ain't too bad. The other two carbs look great.
Thanks for the info on the 'mystery carb'.

[Greg Reid]

Originally Posted by mgarblik

That's a hot idle compensater, generally used on AT applications, especially with AC. Bleeds a small amount of air into the mixture when engine is really hot at idle, to improve idle quality. Some were in the main body near the venturi cluster, some in the location pictured. Not sure what the application is. I would bet Carb King or Cliff would know.

Didn't mean to ignore you on this. Thanks, I knew it was something along those lines...smog stuff I guess.
The carb is in really nice shape. I'm going to try not to cannibalize it just in case it's of some use...for the time being anyway.

[carbking]

Greg - the airhorn is out of round for the same reason that the spider is cracked/broken - overtightening of the air cleaner.

This also is repairable, but is more difficult (well, it requires a special tool). Think about the exhaust expansion tool the custom exhaust shops use to expand exhaust pipes. While the shops use a hydraulic tool, manual tools are available. Using one of these with the toaster oven which I have mentioned here before, it is possible to straighten that airhorn. Sometimes you also need to make a split band which can be tightened on the outside inconjunction with the expansion tool on the inside.

No offense meant to anyone by my next statement, but when you consistently work on stuff for which there are NO reproduction parts (and not going to be ever) you learn to think outside the box.

Once had a customer fly in with a pair of carbs from an early Isotta Franchini, one of which had been dropped by one of my competitors. Fortunately, both carbs were the same. Using the good one for patterns, we cast and made a second carburetor. It can be done.

Jon.

[Greg Reid]

Originally Posted by carbking

No offense meant to anyone by my next statement, but when you consistently work on stuff for which there are NO reproduction parts (and not going to be ever) you learn to think outside the box.


Jon.

No offense taken...in fact, we think the same way.
Believe me, I have imagined in my mind some type of worm screw (think heavy duty hose clamp) type affair that could be tightened until it restored the roundness to the airhorn. I just don't have anything in my possession that I think would do it.
Of course, I could probably buy something that would do it, but it would probably cost more than the replacement!....don't you think? A replacement is just a tad over $100.
I'm all ears if you have any suggestions. I even thought of clamping it in a vise and gently 'massaging' it back to round by squeezing, rotating, squeezing again, etc. but figured I'd do more damage.
On the other hand, I guess I really have nothing to lose.