# 1967 Tempest Coupe



## Billt102 (Feb 6, 2020)

Hello this is my first post, though I have been reading posts on here for quite some time and have obtained so much valuable information, for which I thank all of you.

I purchased a 1967 Tempest coupe about a year ago, and I have been in the process of building a shop on my second property and getting my main home ready to sell, so I have only tinkered with it enough to decipher what it is and what it's issues may be in preparation for starting to make it into what I want it to be.

The car was purchased by me from a fellow here in the Dallas area who purchased it on the internet from a guy out of Utah and he decided to flip it shortly after buying it, that's where I came in. Supposedly an original Arizona car, so the body is relatively rot free. A little surface rust but nothing major. it was born a 326 ST300 AC car. It was in the process of becoming a GTO clone, tail lights and rear panel have been changed out, fiberglass GTO hood, black buckets, floor shift column conversion and an aftermarket promatic2 ratchet shifter "installed". Engine is a 400 bored .040 over with 670 heads, freshly rebuilt (per the receipts that came with the car and visual evidence) almost no miles on the engine, as it was never completed to a fully roadworthy status. The block is dated august '71. It has an Edelbrock Pontiac Performer manifold and Edelbrock 750 carb with HEI with Accel Supercoil installed. I found the receipt for an Elgin E-1794 cam. I ASSUME the guy used original style flat top pistons, but I do not know that for fact. It has a new aluminum radiator freshly rebuilt TH400 (receipt says), and hooker headers with a new dual exhaust was installed with x pipe set up, though it wasn't properly hung or secured so it has the half-open header sound goin on...

Since I have now vacated my previous house, I just drove it for more than the around the block runs I have made numerous times over the last year to use my old gas up and just keep her moving, and I have figured out the following things about the car.

First, one of the motor mount bolts doesn't have a nut on it and the headers appear to be contacting the frame. The motor almost seems a little tilted-back... maybe another header conflict or even possibly the trans mount or crossmember height. 

The car starts right up when it's cold and achieves smooth idle after a few minutes. The distributor was left loose, but the timing appears to be close as it runs and is reasonably responsive, certainly not "dialed in". Once the car has warmed up and gotten up to temp, it turns over very hard when trying to restart. Returns to turning over fairly easily after cooling off. This appears to me to be telltale signs of header heat with the starter issue. More evidence that this was an ongoing problem are that the header pipe by the starter is wrapped in insulating tape, and the solenoid has been relocated to above the drivers side fender well. I don't know if the guy did the relocation because of clearance issue with the headers or an attempt to resolve the heat issue. I believe there was a receipt for a reman starter in the info I got with the car, I'll have to check.

The car has aftermarket gauges; tac, oil pressure and temp. On my 6 mile one and only true drive of the car, temps ran 160-180 on an 80 degree day, but once I hit the driveway to my new place, which is a quarter mile long with 2 stops to open gates, the temp ran up to 210. I am pretty much positive this is because there is NO shroud on the radiator whatsoever and the fan looks to be 4-5 inches from the radiator.

There are many other issues with the car, such as the guy installed tubular upper a arms but it still has the stock lowers. one shock on the front was not bolted up and the other one is missing in action completely. the aforementioned shifter installation is shoddy with no cover on it, no console and I am not real crazy about the ratchet shifter action anyway... and quite a few electrical bugs to chase. Typical stuff, BUT my questions related to this first post are as follows.

Do you think I am on the right track on my assumptions that header heat is causing the starting issue? 
I am pretty sure I can eliminate the temperature spike I saw coming up my driveway with installation of a shroud, though I am highly considering going with electrical fans on it, am i thinking right on this?
MAIN question: I know the 670 closed chamber heads result in 10-something static compression, can have issues with pre-detonation, running 93 octane pump gas, but I am wondering if the cam installed may be "helping" this, as I have not noticed any sort of pinging or pre-det lagging... I will drop the cam specs below.

Series: Performance
Year: 1955-1981
Make: Pontiac
Engine: 265-455 V8
RPM Range: 2000 to 4800
Camshaft Type: Hydraulic Flat Tappet
Intake Valve Lift: .454"
Exhaust Valve Lift: .454"
Advertised Intake Duration: 272°
Advertised Exhaust Duration:272°
Intake Duration @ .050":216°
Exhaust Duration @ .050":216°
Lobe Separation:110°
Intake Centerline:105°


I am just trying to get this to be a fun reliable driver without spending more than the car's value, which is certainly capped by being a Tempest. I love the body style and I can have fun with this as it has good bones and I can do most of the tying up of loose ends myself, and then maybe I will sell her and start over with a real GTO...


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## BLK69JUDGE (Jun 10, 2010)

first off WELCOME to the forum !

your lookin good ........ ! glad you can post pictures ,,,because it really helps ...

great write up ... so .... this issue has been discussed alot here on the forum ....overheating ,,,

this will bring out alot of sugestions so be ready ....

if it were my car ... here we go... I am NOT a certified mechanic just a backyard wrencher but 

only GM 's .....so ....

get the timing set correctly ... adjust the carb ... check for correct vacuum port for the vacuum advance 
get a fan shroud ,,,, put in a quality thermostat ...
get or make sure your water pump impeller is clearanced to the divider plate ... and a quality pump ,,,,no tin bladed impeller s .....
..you may have the 11 bolt water pump being you state its a 71 block ... that would be good ...
engine pictures can help ... from different angles...
correct fitting fan helps .... there is little flaps that go along side the radiator and the radiator suport on AC cars ,,, this can help also
correct or changing pulley diameters can help too 

so ,,,, thats my intro ,,,,, 
timing
shroud and rubber deflectors,,,, depending on how or what style your aluminum radiator is .... 
water pump check
correct fan
would be my steps .....
big tranny cooler too 

Scott


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## 67ventwindow (Mar 3, 2020)

Welcome !! Great looking Tempest.I always thought it was a great name for a car


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## Billt102 (Feb 6, 2020)

BLK69JUDGE said:


> first off WELCOME to the forum !
> 
> your lookin good ........ ! glad you can post pictures ,,,because it really helps ...
> 
> ...


thanks Scott. I picked up my buddy’s good timing gun with the adjustable scale today to get the timing set. fan appears to have an 18 1/2” diameter and is back about 4 inches from that radiator. I’m looking for a fan shroud now. It’s a 6 blade fan. I think the original style fan shroud will be too shallow I probably need one 5 or 6 inches deep. attached a few pics including of the headers up against body parts.


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