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Just Joined, 'Cause I Just Bought (a 66 Tempest Custom...

6K views 98 replies 18 participants last post by  SLSTEVE 
#1 · (Edited)
...with the 326 2BBL, 3-speed on the floor).

All indications are that it's all original, unrestored, except a repaint in the early '90s.

I'm quite happy with it. The odometer reads 70K miles and I'd bet it hasn't turned over.

Lots of questions, but I suppose a couple on the top of my mind are whether the 250 hp 326 will respond to a 4BBL carb and other basic mods. Cam, headers?

Also...Wikipedia says 3 trannies were available - the Powerglide, 3-speed manual on the column or a 4-speed on the floor. It came with the original window sticker, consistent with what it actually has...a 3-speed manual on the floor, which the seller told me has the Hurst shifter. The window sticker says "3 speed-floor-fully synchronized". Is Wiki wrong in stating that the 3-speed manual was on the tree (no mention of floor shifter)?

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#50 ·
take a peek at your rear end cover and make sure they get you the correct gasket,
I think your gasket should be the one with the ears cut off see below View attachment 140815
Thanks for the tip. Indeed it is as such. And as we can see, those bolts suggest that cover hasn't been removed in potentially decades (possibly 5.5 decades?). I think back in the day (including myself), many weren't too good at changing the gear oil. I had my Chevelle 10 years and never did (was young and naive).
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#51 ·
Your tip is now doubly appreciated. Advance had the wrong (like above) one sent over from another location. He couldn't find the correct one at first but went into a different section in the system (?) and found it...getting couriered to my local store tomorrow.
 
#58 ·
Speaking of heater hose...since I wasn't getting any heat into the cabin (though the vent fan works), I checked to see if the heater hose was hot. It definitely was not. The main radiator hoses were, but both heater hoses in and out of the firewall weren't even warm.

That's perplexing to me...but hopefully clues someone into a solution to get some heat goin' in the cabin.
 
#56 ·
awesome it still has the posi tag intact the rear cover should clean up nice, after you remove the cover you can find your axle ratio divide higher # into lower #
Right...was happy to see that tag as well. Though no reason to suspect the numbers won't be there, I learned they're simply the number of teeth on the ring gear and # of teeth on the smaller vertical gear (directly connected to the axle shaft).

As I've done w/past diff covers, I'll repaint it (after hitting it with a brillo pad (or ?...maybe a drill bit style abrasive disc?) to get the surface rust off. I'll also rinse out the gears with plenty of brake cleaner to get every last bit of nasty old gear oil out. Not too optimistic, but I'm hoping the fresh gear oil will quiet the whining down a bit. If it doesn't, I'll have it rebuilt.

And though one can only see a bit of it, that gas tank has lost its youthful beauty, so its time has come. Spectra (Canadian company) makes repro tanks for it, so I'll get one of those (and new straps) and get a nice new tank installed.
 
#59 ·
Maybe I should mention the upper lever on the vent/heater controls will only move between off and heat...clicks to there, but will not move to the deice on the right. The fan definitely produces air flow on the floor...and at the windshield (which it shouldn't if deice isn't selected, yes?
 
#61 · (Edited)
TK
possibly a heater core issue, no coolant flow from engine , maybe remove both heater hoses and attach a water source to confirm no flow in & out could be sludge in the heater core, the fuel tank may be good inside but ugly outside, , I would soak the bolts for the tank straps , the fuel sending unit may be fragile so keep an eye on that
I am curious what gear set the rear has installed with a factory 3 speed
 
#65 ·
TK
possibly a heater core issue, no coolant flow from engine , maybe remove both heater hoses and attach a water source to confirm no flow in & out could be sludge in the heater core, the fuel tank may be good inside but ugly outside, if you decide to do the tank , I would soak the bolts for the tank straps & you may need new tank straps , the fuel sending unit may be fragile so keep an eye on that
I am curious what gear set the rear has installed with a factory 3 speed
Well, I was hoping I wouldn't hear heater core. After several years of no-heat winters in San Diego, I replaced the core in my Chevelle. Wasn't as experienced (nor the wisdom of how important the right tools are) at "bigger" (bigger than r&ring an alternator), so it took me all day to accomplish.

Agreed...I'm assuming it's okay inside, but it's so ugly, it's time. I ordered a new Spectra tank and new straps (with strap pads) a couple hours ago. I r&red the tank in my TR a couple years ago, so I know what I'm up against. Okay...I'll be very careful with the sending unit.

Very curious too about the diff gear. The high today is supposed to be 37 degrees. The forecast for Tuesday is 56, so haven't decided. Might happen today if I get too antsy. But I'll definitely let you know when I learn the gear ratio.
 
#62 · (Edited)
not sure if you have used RA? I have sourced them before and had good luck, I also get discount codes(5%) every once in a while
 
#66 ·
I've used Rock Auto many times...great prices. I spaced it 5 am and went straight to eBay (see they also have the Spectra)...paid $20 more for the same tank before the 5% discount (I'm often emailed the discount code, but it expires...have Googled the current code so can always get it). I'll likely be using RA lots for this car though...will be ordering KYBs shortly through them (and possibly coil springs). But good tip/reminder...
 
#67 · (Edited)
Was curious about whether it had a stat as well. Preliminary indication is that it does, as I saw no coolant circulating with the rad cap off just after cold start-up. That's not definitive (could be stuck closed), so I'll be doing a direct check soon.

Do you happen to know how the heater core in these is accessed? It required removing the wheel well in my Chevelle. I'm hoping some might be accessible through the passenger compartment's heater box. I'm sure I'll find a DIY vid on Youtube...
 
#68 ·
Looks like I might be replacing the water pump soon as well. There's a small leak somewhere at or around it...looks like at the mating surface between it and the engine. Just enough to detect a bit of steam rising.

I see it's got a new radiator, so that's good.

That alternator trips me out...looks decades old, but obviously still working. Hard not to not justify replacing it as well.

Belts look okay, but I'll probably replace those as well soon.
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#69 ·
I know you said the cig lighter may not be working but this may work in the interim this is from Amazon of course if its just a blown fuse for the cig lighter
the alternator looks to have been replaced (stickers on the side) you can always confirm the stamping on the case
water pump not sure if there were different w/p for that year but you may want to measure the mating flange, if you do the water pump you are half way to the timing gear set, if the 70k is correct I would just bite the bullet and replace the timimg gear it will go soon if it is the the orig
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#77 ·
Rock Auto has two different shocks, one for "w/heavy duty suspension" and one for "except heavy duty suspension". I just called KYB tech support, asking if it was just that one was stiffer or if they vary in size/fitment. The only thing she could say was restating in so many words that it depends on the specs of the vehicle.

The window sticker line item says "springs & shocks-ride & handling"...suggesting the possibility that it's what KYB refers to as the heavy duty suspension. But because it's not clear, I'm hoping someone can give some clarity on which suspension it has.

1966 PONTIAC TEMPEST 5.3L 326cid V8 Shock Absorber | RockAuto
 
#82 ·
Nice!!!

As far as upgrading the engine:
Pontiacs have great parts interchangeability. Pontiacs left the factory with essentially flattop pistons (shallow dimples for valve clearance), so compression ratio changes were because of combustion chamber volume. Your 2-barrel heads are about 9.5:1 if I remember right—not bad for today’s gas.

Intake manifolds 1965 and later will bolt on. Later heads have taller exhaust crossover ports and may require block off plates. wallaceracing.com has good info on year breaks, gasket sets, etc. 65-66 tripower is a bolt-on. 65 has a smaller center carb.

4 barrel intakes may be for Carter or Rochester carbs. Rochester Qjet was first available on the GTO for 67 (big cars still used Carter).

I think the 326 4barrel used a different cam than the 2 barrel. With a manual trans, you could could go up one more step; I think GTO used 067 cams for automatic and 068 for manuals. 326 cams were a little milder.

Preferred exhaust seems to be the cast iron HO/RA manifolds—easier to install than headers, and less likely to leak. It will require different head pipes. All available aftermarket, and choice of diameters and materials for head pipes.

A-bodies came as either post (like your car) or hardtop. Vinyl top was an option with either configuration. They were also available with two-tone paint that used vinyl top trim as a divider between the colors. Paint codes appear on the trim tag on the firewall.

The Paul Zazarine book is a good intro to factory equipment and options.
 
#85 ·
Nice!!!

As far as upgrading the engine:
Pontiacs have great parts interchangeability. Pontiacs left the factory with essentially flattop pistons (shallow dimples for valve clearance), so compression ratio changes were because of combustion chamber volume. Your 2-barrel heads are about 9.5:1 if I remember right—not bad for today’s gas.

Intake manifolds 1965 and later will bolt on. Later heads have taller exhaust crossover ports and may require block off plates. wallaceracing.com has good info on year breaks, gasket sets, etc. 65-66 tripower is a bolt-on. 65 has a smaller center carb.

4 barrel intakes may be for Carter or Rochester carbs. Rochester Qjet was first available on the GTO for 67 (big cars still used Carter).

I think the 326 4barrel used a different cam than the 2 barrel. With a manual trans, you could could go up one more step; I think GTO used 067 cams for automatic and 068 for manuals. 326 cams were a little milder.

Preferred exhaust seems to be the cast iron HO/RA manifolds—easier to install than headers, and less likely to leak. It will require different head pipes. All available aftermarket, and choice of diameters and materials for head pipes.

A-bodies came as either post (like your car) or hardtop. Vinyl top was an option with either configuration. They were also available with two-tone paint that used vinyl top trim as a divider between the colors. Paint codes appear on the trim tag on the firewall.

The Paul Zazarine book is a good intro to factory equipment and options.
65 gto the 067 was on all 4 bbl cars 068 on tripower. The 066 grind was used i think on some automatics especially in the big cars , i think it was a tad milder than the 067.
 
#84 ·
I like those hubcaps, i had a set on my first car which was a 65 lemans coupe (326 2 bbl) always liked the way they looked.

the 326 4 bbl i think had 285 hp so you can see how much you would gain if you upgraded. Definitely if you want more power drop in a 400/428/455.
definitely looks like you have a nice straight car, and its in one piece so you can enjoy it while you work on it.
 
#88 ·
I like those hubcaps, i had a set on my first car which was a 65 lemans coupe (326 2 bbl) always liked the way they looked.

the 326 4 bbl i think had 285 hp so you can see how much you would gain if you upgraded. Definitely if you want more power drop in a 400/428/455.
definitely looks like you have a nice straight car, and its in one piece so you can enjoy it while you work on it.
Though I don't mind those who tribute/clone the performance models, I'm not tempted with the tempest. I've come to really like this 326, so at best, maybe upgrade to emulate the HO version.

I usually drool when I see cars with the big displacement motors. But something is compelling me to continue to retain the same spirit of whoever's owned it the last 55 years, at least for the most part...keep it a cruiser.

I really like the Rallye I wheels...have identical 15x7s ordered (though they're telling me it might be May before they ship).

Thanks for your reply Scott!
 
#89 ·
Those mods are a temptation...the HEI distributor especially, to help protect the motor. Though I'm still learning how much gas to give it (have flooded it a couple times, turning it into a 30 second cold-start session). When warm, no gas, instant start.

And once warm, the motor purrs...at idle, it's exceedingly smooth...only just enough vibration from the seat (with some conscious focus) to detect that the engine is running.

Thanks for your comments Robert...
 
#91 ·
If you ever have to overhaul your engine, one of the cheapest ways to improve performance, mainly to get great torque, would be to stroke it with a 4" crank from a 428 (IMHO). Pontiac blocks are all the same dimensions from the 1955 engine to the last ones c1981. Great for crankshaft interchageability.

Other members have mentioned the Wallace racing site for great tech info. It is and here's the link:


If you do any engine work, my favorite place to go whether its stock or modified is Butler Performance. They also have a great tech info section listed at the top of the home page. My experience if you order parts and need help, its best to call them. Some of the hourly people are OK but if you need hard or rare info, ask for David Butler. I found him to be a fountain of info, especially since he's done Pontiacs for decades. Here's a link to their site:


Love your Tempest, a rare Pontiac unicorn. Enjoy

(Another Pontiac forum with good info (if you haven't already used it) is the PY forum):

 
#94 ·
PJ is right about the 428 4" crank but it was near my bedtime and I neglected to mention I was thinking after market crank w/ no mods needed.

Moving along, whether you keep the 2gc 2bbl or acquire an afb 4bbl, I've found the best place to get anything from rebuild kits to some hard to find carb parts, the place to use is The Carburetor Shop. Jon is a great guy and given your carb number, he will make a rebuild lkit specifically for your carb. The auto parts stores and Rock Auto supply you with universal carb kits that use generic parts and frequently don't fit/work. This is because of the low demand for carb stuff. Jon is a fountain of info too. Here is the correct link since "carb shop" has a zillion places listed on google:


If you haven't yet found it, Ames is the great place for Pontiac parts (body, interior, chassis, engine). They are great with advice on the phone as well as ordering. You can download their catalog or request a paper one.


Catalog download:


Best of luck with your Tempest! :)
 
#95 ·
It's actually you guys I consider the fountain of info. Just pointing to vendors and Pontiac parts specialists is invaluable info for me. Thank you gentlemen...

I'll take my time and keep considering based on the options you've provided. I just received the front coil springs, KYBs, drop spindles and went and got new wheel bearing and ball joints (though I think those are okay, it only makes sense to install fresh bearings and balls joints). So...I'll likely endeavor the springs/shocks and spindles tomorrow.

And before I consider any upgrades to the motor, I just gotta upgrade to at least front disc/power brakes. The 4-wheel unassisted drums won't cut it with performance (power/handling) enhancements.
 
#97 ·
You mention a disc upgrade. I put this kit from Summit on my 65 GTO a year ago worked very nice, easy install, huge upgrade vs the drums. Summit Racing SUM-BK1501 Summit Racing® Complete Drum-to-Disc Brake Conversion Kits | Summit Racing

Its very similar to other kits out there from Right Stuff etc, maybe even the same kit. I onluy had to fab up a couple of short pieces of the 3 brake lines and get an adapter (flare nut bushing) between the existing rear brake line size and the proportioning valve.
You need 15" wheels for this one , they do have one with 10.5" rotors which clears a stock 14" disc brake wheel if you want to stick with the hub caps.
 
#98 · (Edited)
Awesome info. I got The Right Stuff sitting on a shelf now. Hopefully I will be bolt it on with the front and rear suspension next month. It's supposed to fit under stock wheels of the 65. We'll see. It'll be manual 4 wheel disc with parking brake. The body is off so now's the time to run the lines since it's a convertible frame.
 
#99 ·
Awesome info. I got The Right Stuff sitting on a shelf now. Hopefully I will be bolt it on with the front and rear suspension next month. It's supposed to fit under stock wheels. We'll see.
OMG! Have you ever ran all new fuel and brake lines with the body on the frame? Just about impossible to get them all correctly positioned and clamped. Especially when you know you can’t remove the body from the frame anymore because the $?@/:??-@painter failed to weld the new body bushing bolts to ANYTHING prior to him welding the floor pan closed! I told him to put everything back OE but he didn’t. And guess who is paying for it?
In
You mention a disc upgrade. I put this kit from Summit on my 65 GTO a year ago worked very nice, easy install, huge upgrade
Yeah, when I bought the car the resto had already begun by the PO. He had the frame powder coated grey(who does THAT?), he installed new front disc brake with slotted rotors, and supposedly had front end all rebuilt. After crawling under and around that car for the past few months, I am beginning to suspect that the front end is in used condition. All of the ball joint boots are cracked and split open, everything looks like it is clean but that’s what a high pressure washer accomplishes, so the jury is out on that for right now. I plan to get her running to break in cam and new rearend and then get her on the road to assess front end condition.
I have to say here that everything on this car has been a major struggle from the beginning. Although the rotors and disc brakes are new, it took me 4 sets of brake hoses to finally get hoses that fit and worked. I guess if you buy a disc brake kit everything for that installation will fit and function for that year and model car. I had to pull a caliper and take it to the local NAPA store to source the correct sized banjo bolts. Turned out they were 10mm x 1.5 x ?. Then the hose issue. Ordered all three from NAPA. 65’s didn’t come with front discs, so when were they factory installed? 68, so get me a set of those, nope, book only goes back to 71, so get me those. They didn’t fit-too short. Got a pair for 73 GTO and same thing. Ended up going through the parts book with counter guy at NAPA and found a pair of 14.5 inch hoses with banjo fitting on one end and 3/8 inch inverted flare fitting on the other end. Haven’t tried them yet but they look promising.

Its very similar to other kits out there from Right Stuff etc, maybe even the same kit. I onluy had to fab up a couple of short pieces of the 3 brake lines and get an adapter (flare nut bushing) between the existing rear brake line size and the proportioning valve.
You need 15" wheels for this one , they do have one with 10.5" rotors which clears a stock 14" disc brake wheel if you want to stick with the hub caps.
 
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