This is my story and I'm sticking to it......

I bought a 1969 GTO that was advertised on this board a few months ago. It was a divorce situation and the woman ended up with a car (partially disassembled and in mid-restoration) that did not run but had a freshly rebuilt engine sitting between the rails (so she said). The only thing she knew about it was that the guy that built the motor used to race Pontiacs.

I'm now trying to figure out what the engine builder had in mind when he built the car. Here's what I found. It's a 1975 WT block with 1971 code 96 heads (86cc I think). It has an Edelbrock torker intake without a carburetor. The cam measures about 218 degrees intake duration and 230 exhaust duration (both measured @ 0.050"). The lift is .447" intake and .468" exhaust. Lobe separation measures to be about 130 degrees (can that be right?). There is no identification on the front of the cam. The cam gear has the numbers S305 on the cast surface and the crank gear has the numbers S371 stamped into it. The timing marks point at each other at TDC rather than both pointing up as they should be since it's a post 1968 motor.

I'm going to assume the motor has been bored since it looks like it has new (never fired on) pistons when looking through the spark plug hole. The engine builder also installed new "4 tube" headers.

I'm certainly not a Pontiac performance expert, however, considering all of this stuff together make me think this motor was built for more of a "drag strip" application than a street application. Can anybody confirm my suspicions? I want this car to be a daily driver, not a drag racer. What can I do to build it for short daily commutes without investing a whole lot of money.

Thanks in advance for any help.

Vrroom

This is my story and I'm sticking to it......

I bought a 1969 GTO that was advertised on this board a few months ago. It was a divorce situation and the woman ended up with a car (partially disassembled and in mid-restoration) that did not run but had a freshly rebuilt engine sitting between the rails (so she said). The only thing she knew about it was that the guy that built the motor used to race Pontiacs.

I'm now trying to figure out what the engine builder had in mind when he built the car. Here's what I found. It's a 1975 WT block with 1971 code 96 heads (86cc I think). It has an Edelbrock torker intake without a carburetor. The cam measures about 218 degrees intake duration and 230 exhaust duration (both measured @ 0.050"). The lift is .447" intake and .468" exhaust. Lobe separation measures to be about 130 degrees (can that be right?). There is no identification on the front of the cam. The cam gear has the numbers S305 on the cast surface and the crank gear has the numbers S371 stamped into it. The timing marks point at each other at TDC rather than both pointing up as they should be since it's a post 1968 motor.

I'm going to assume the motor has been bored since it looks like it has new (never fired on) pistons when looking through the spark plug hole. The engine builder also installed new "4 tube" headers.

I'm certainly not a Pontiac performance expert, however, considering all of this stuff together make me think this motor was built for more of a "drag strip" application than a street application. Can anybody confirm my suspicions? I want this car to be a daily driver, not a drag racer. What can I do to build it for short daily commutes without investing a whole lot of money.

Thanks in advance for any help.

Vrroom

It all seems pretty street oriented to me from the info you have provided.

First the cam,any ID #'s would likely be on the rear of the cam.

From the specs you quote it sounds like a crane or possibly a crower cam.

Cranes #283942(h-272-2/hmv-272-2)cam is real close to your specs.

Crower has a couple similar grinds too(#60918/288H,and #60241/276HDP).

These would indeed be considered a "street" cam.

My money would be on the crane,and all are ground with a 112lsa.

As far as the rest it sounds like a more or less stock low compression 400 from the codes you give.

The '71 #96 heads would have originally been appx. 96-98ccs.to be certain of chamber size would require cc'ing them.And those heads on an otherwise unmodified 400 with flattop pistons would give around 8.0:1 compression ratio.

Again this sounds like a "street" type build to me.

There are 400 "domed" pistons from TRW/federal-mogul #2279,if these were used with the #96 heads it would have about 9.25:1-10.0:1 depending on if the heads were milled any.

The torker is the one item that seems "out of place" here,though that could have more to do with what was available as opposed to being specifically chosen for the combo.

sell or trade the torker for a 68-72 stock intake and qjet and with what you have listed it should be a very nice street oriented performance motor.
That cam is only slightly larger than a regular 068 factory GTO cam, should idle smoothly with just a little lope to it.

The 218/230 @ 050 brings back memories of the old Crane Blazer series of cams. They used these 050 numbers for quite a few engines, but not 100% sure about the Pontiac. Lift with 1.5 rockers was around 0.450/0.465", close to what you got. The LSA was usually 114 for the Blazers.

Thanks for the input. It's much appreciated. I'm off today to get a degree wheel to see if I can measure the LSA a little better. Calculating 130 degrees seems a little strange from what I've read.

Here are some more questions:
1. The rocker arm nuts have set screws in the middle. I didn't think pontiac's had adjustable rocker arms, do they?
2. The motor has not been operated since being rebuilt and I've rotated the crank several times. Do I need to remove the crank and put some kind of lubricant on the journals before I put it back together and fire it up? Or, do I just lube it with the oil pump before firing it?
3. I have a stock 69 GTO intake to put on the motor in place of the torker, however, is there a better choice over the stock unit? Maybe something I can pick up at a swap meet or something like that?
4. What size and brand carb should I use with this cam? Q-jet? Holley?......etc?

Thanks for all your help guys. with your help, I'll get this thing back together sooner rather than later.

Vrroom

I'll give my thoughts on your questions:

1.Sounds like they used polylocks to make the valvetrain adjustable to work with the aftermarket cam.While an acceptable modification I generally prefer to convert to straight 7/16" BBC style studs over the 7/16"-3/8" "bottleneck" studs.This would be an easy thing to change at any point though.

2.I would be comfortable with making sure the engine is well primed before fireup as far as the bearings are concerned.Though I would probably pull down the valvetrain and make sure the friction points all have some lube on them(lubriplate or such).And pull the valley pan and see if the cam has any break-in lube on it,if not I'd make sure it did.And I would recommend the use of GM EOS upon the initial startup also.

3.As far as intakes,the stock one is a good choice.And if you prefer aluminum an edelbrock performer would be as good as the stock performance wise and a few pounds lighter to boot.I dont think this combo would gain any by using any other choices(performer RPM,torker I or II,etc.,etc.).You could probably find someone to trade the torker for a performer if you felt inclined.

4.This falls more into the area of personal preferance and what your comfortable working on.The Q-jet is an excellent street performance carb when properly tuned for an application.And other carbs can work very well also.As far as CFM I'd stick to around 750 CFM on this one myself.I would likely use a 3310 750 vacuum secondary holley with an electric choke and a few of my usual modifications here.The Q-jet would have an edge in a couple ways if set-up correctly though.

So hope that helps you some,good luck and welcome to the boards here.Most folks here will do what they can to help you with your questions or problems so your able to enjoy your pontiac.

This has been great information.

One more piece of information that I just uncovered is that it has, what I think is, a 22-2800 stall speed torque converter. It looks brand new and I can only identify it by the numbers 46012 written on the tranny side of the converter. A google search reveiled a "Boss Hog" converter that matches this part number.

I hope that converter is OK with the cam I have.

Voorrm

That convertor might be a little on the loose side but should work for the most part.It kind of depends on the gears in the rear end and what size tires you plan on running.

With a 2.73 or 3.08 gears and a tall(say 28"-30")tire you'll probably not enjoy it as much as if it had 3.23 or 3.55 gears and a slightly shorter(say 26"-28")tire.

Never used that brand myself so dont have much to say about that.Just be sure to use an aux. trans cooler also.

I'd go ahead and try it out.

Well, now the cam question is answered. I took it out this afternoon. It's a Crane H-288-2.
Duration @0.050 = 226/234, Lift is 458/473, Lobe separation is 114 degrees.

I don't know what that means right now, but I'm going to try to find out.

My hope is that this combination, along with substituting a stock intake for the torker I, will be a good machine for the street.

PONTIAC V8 CAMSHAFT HYD;
CRANE 283951 $114.95
Manufacturer
CRANE Part Number
283951

Description

<span class="ev_code_RED">Part Number: 283951 Grind Number: H-288-2 (REPLACES CCH-288-2)</span>
Engine Identification:
Start Yr. End Yr. Make Cyl Description
1955 1981 PONTIAC 8 FAIR IDLE, MODERATE PERFORMANCE USAGE, GOOD MID-RANGE HP, MILD BRACKET RACING, AUTO TRANS W/2500+ CONVERTER, 3400-3800 CRUISE RPM, 9.5 TO 11.0 COMPRESSION RATIO ADVISED. BASIC RPM 2500-5500
Engine Size Configuration
265-455 C.I. V

Valve Setting: Intake .000 Exhaust .000 HOT

Lift: Intake @Cam 305 @Valve 458 All Lifts are based
on zero lash and theoretical rocker arm ratios.
Exhaust @ Cam 315 @Valve 473
Rocker Arm Ratio 1.5

Cam Timing: TAPPET @.004
Lift: Opens Closes ADV Duration
Intake 29 BTDC 79 ABDC 288 °
Exhaust 81 BBDC 35 ATDC 296 °

Spring Requirements: Triple Dual Outer Inner
Part Number 99840
Loads Closed 90 LBS @ 1.578 or 1 37/64
Open 262 LBS @ 1.138
Recommended RPM range with matching components
Minimum RPM 2500
Maximum RPM 5500
Valve Float 6500

Cam Timing: TAPPET @.050
Lift: Opens Closes Max Lift Duration
Intake 4 BTDC 42 ABDC 109 226 °
Exhaust 56 BBDC (2) BTDC 119 234 °

Remarks:
THE MINIMUM CLEARANCE REQUIRED IS .040 BETWEEN THE RETAINER & ROCKER ARM WHEN VALVES ARE CLOSED.


283951
No Image

Well the cam/convertor/and torker becomes more understandable with that difference.Not all good news though,now the compression is a little low for the cam IMO.

Might help a little to install the cam 4 degrees advanced to help that some.

And that cam will need the adjustable valvetrain,so that explains the poly-locks.

I'd want to find out exactly what pistons are in there,and exactly what the head chambers cc at to come up with a better idea what the CR is now.

I'd probably still prefer to use the performer also.

Also do you have any idea what gears it has?

This motor is starting to be an excercize in frustration.

Today I removed the passenger side head to get a look at the pistons and also determine the volume of the combustion chamber. I found the following...

The cylinder walls look to have a freshly honed surface, although there are is a slight bit of rust in some places (the engine sat for quite a while before I bought the car). The bore measures roughly 4.120". The pistons look used. They have punch marks on the tops indicating the cylinder they were in (2, 4, .... etc.). They are normal 400cc flat top pistons with the eyebrow type valve reliefs. The piston in the #8 cylinder has a very large 45 degree chamfer around the top. Maybe the repair shop removed some damage from this piston....who knows?

The heads looked good as well. They are clean and undamaged. I measured the volume on two of the chambers and both came out to be 96CC's.

As I was carefully reinstalling the cam I accidentally pushed it in a little too far and it bumped up against the freeze plug in the back of the motor. I just bumped it ever so slightly and it knocked the plug out. Arn't those plugs supposed to be pressed in a little better than that?

So here's what I have:
1975 400cc block with a 4.120" bore and a 3.75" stroke. The deck height is about 0.010" above the piston when it's at the top of the stroke.
The heads (1971-#96) have 96CC chambers which puts my CR at about 8.5:1. The cam is a Crane Cams #H-288-2 which has a 226/234 duration @ .050", a lift of 458/473 and an LSA of 114 degrees. The torque converter has a stall speed of 2200 - 2800 RPM. I don't know the rear end ratio but the GTO is an A/C car and probably has a 3:23 or 3:08 ratio.

At this point I just need a cheap and quick way out. This motor will only be in the car for a short time while I finish the restoration. I intend to put the original motor in the car in a few years. Right now, I'd like it to be a good driver. I think I can do that by installing a different cam along with a different torque converter and a stock intake. But what cam choices are there for an 8.5 CR?

Thanks in advance for the suggestions guys.

Vrroom

I run a bosshogg 24-2800 stall with 3.31 gears and 28 inch tires with a 428. The stall is closer to 28 than 24. I have had no problems with the convertor. The guy I bought it from has used that brand for 10 years and never had any trouble. He raced a 460 Ford. Ne told me with a 400-455 the convertor would be closer to the high side number.

Hope this helps some Patrick

Looks like I'm going to have to change some things to get where I want to be. I've already got an offer to swap my torker intake for a performer intake. Now I need to find a good street cam for #96 heads and the right torque converter.

The cam and lifers in my motor are brand new if anyone out there wants to buy it or do a trade deal. The torque converter is also new. I'll sell or trade it too.

I think I'm going to have the heads milled 0.060" to decrease the volume of the combustion chambers to about 85-87 cc's. That should give me 9:1 (or a little higher) compression.

Anybody want to suggest a cam for this build?

Thanks,

Vrroom