Topics

1

General Discussion / Factory documents regarding jetting over the years?

« on: January 10, 2013, 06:20:45 AM »

First, I want to thank this board for their help and wisdom, I have asked more of it than I've been able to provide in return.  Hopefully some enjoy reading the blog authored in the build of my Camaro (http://www.rhoadescamaro.com/build)

Presently I am trying to understand if Chevrolet or GM ever, since the Camaro started in 1967, provided a service manual, technical bulletin, memo, or any other kind of factory-authored document, authorizing or describing how a dealer's service department or owner, could change the metering jets (or any of the other common tuning elements like power valves, vacuum secondary springs, or accelerator pump components) in their first generation Camaro.  Specifically I'm interested in the Z28 from 1967 and its Holley, but such documents, if they exist, might be much more broad and cover the entire Camaro line.

Some situations that might have warranted changes - a dealer operating in Denver, might have wanted to sell their cars with leaner than original jets?  As leaded fuel began being phased out for unleaded, that too may have prompted some kind of manufacturer-authorized carburetor component change? 

Basically, anything from the factory saying the owner could make carburetor component changes, for purposes other than racing.  It could have been authored in the 60's, 70's, maybe even the 80's, which is ok, as long as it applies to the '67.

If something like this exists, it opens up a lot more tuning options for me, where I have to run a stock carburetor on my race car.

I've just about exhausted my Google-Fu, and in the past this place has been great at revealing info that exists nowhere else on the Internet...

Thanks so much!!

2

Maintenance / Advice for tuning a stock-ish 302

« on: January 06, 2013, 05:17:25 AM »

Hello,
Finally got my project car running - http://www.youtube.com/watch?v=zv8kNY3CjQg   

It is basically a freshly rebuilt clone of a stock '67 Z28 302.  Stock block, crank, rods, pistons, cam, heads, etc.  Carb is a stock re-issue carb I asked about here: http://www.camaros.org/forum/index.php?topic=10127.0

It came with what I believe are the stock jets, 68 primary and 76 secondary, and likely stock power valves, accelerator pump and cam, vacuum secondary spring, etc.  I'm not allowed to change any of those parts in the class I'm building the car for.  Here's an example of the sort of racing it is: http://www.youtube.com/watch?v=zUs_rZ-Psf8

The car has Doug Thorley tri-y 1-5/8" headers (mid-range torque is more important than top-end HP for what I do), a 2.5" Magnaflow exhaust with x-pipe, and a high-end Mallory distributor and coil.  Has 100 octane in it at present, I have no problem running that long term.

Looking for advice from the group here - suggestions on initial timing advance, total advance?  I have some flexibility in advance curves, mechanical and vacuum.  (manual here: http://prestoliteweb.com/Portals/0/downloads/mallory/pdf/Mallory_Instructions_max_fire_1248214_1248204_1255104_1255404_1256704.pdf - I'm using the curve that has 6 degrees advance at 2000, and 19 at 5200).  Also have initial timing at 12 degrees but really have only started it a couple times and haven't done a basic idle tune yet.  Vacuum gauge is on its way.  At present it has a bit of a stumble off idle, even though idle seems rather high (12-1500rpm).  My engine builder suggested this advance curve, but I forget where we had initial timing when it was on the engine dyno.  I suppose to get to the normal 36 degrees total, would need 17 degrees initial?  Need to have a timing approach that is safe considering the car will probably be lean most of the time with stock jets.

Looking for suggestions on adjustments I can make to the carb (idle, float levels, etc.) to help it perform under a transient-throttle racing situation?  What I do is a lot different than drag racing; we are part-throttle most of the time and need good transient response.  Looking at some kind of tube to run between the primary and secondary bowl vent extensions, to keep the carb from flooding under heavy braking, which would be allowed since it's not an internal modification.

Thanks so much again for the help!

3

Restoration / Source for quality power steering pump?

« on: November 12, 2012, 06:04:59 PM »

In putting my car (http://www.rhoadescamaro.com/build ) together, got to the point yesterday, where it was time to add PS fluid.

As my car was originally manual steering, I'd bought this pump:
http://www.classicindustries.com/camaro/parts/a6113.html

Got the lines all cinched up and added a couple ounces of fluid, turned the wheel back and forth a bit (car in the air, not running), no apparent problem.  So added about half a quart...
and it began POURING onto the garage floor!

Fortunately it was in a single stream, so was able to put the bottle right back underneath and collect a lot of it.  Still a big waste and mess.

The leak wasn't coming from any of the hose fittings - it appeared to be from between the main body of the pump, and the outer shell, which seems to be how the reservoir attaches.  So much for a quality remanufactured unit!

Has anyone here had any luck with an alternative source for this kind of part?

Thanks!!

4

Restoration / eBay '67 Holley Z28/L78 carb

« on: October 29, 2012, 09:41:07 PM »

http://www.ebay.com/itm/1967-Camaro-Z28-L78-302-396-Holley-carburetor-3910-751-May-67-/330651887642?pt=Vintage_Car_Truck_Parts_Accessories&hash=item4cfc63681a&vxp=mtr

Have you guys seen this sort of thing before?  It looks too new to be real?  I asked the seller about is origins and he replied "carb is built to 1967 L78 and Z28 specs it is a new issue that only I have..."

He has good feedback (100%) and lots of other current auctions with legitimate used parts.

Wondering if it might work on the '67 Z28 clone/tribute I'm building (http://www.rhoadescamaro.com/build)

5

Restoration / Source for Z28 water pump?

« on: August 16, 2012, 04:59:10 AM »

Working on building my '67 as a tribute and "technically correct" Z28 clone, for national-level SCCA autocross (http://www.rhoadescamaro.com/build)

I have what I believe is a correct pump bypass elbow: http://www.rickscamaros.com/camaro-water-pump-bypass-fitting-90-elbow-z28-1967-1968.html

But I've bought two different water pumps, and it is too small to thread into the opening at their tops.  My eyeball says the water pump openings are about 1", and the elbow threads are more like 3/4".

I'm sure you guys have seen this site, it's awesome, I reference the pictures all the time.  Looks like the elbow should thread right into the water pump:
http://67z28.com/gallery/albums/67%20Z28%20Restoration%20Photo%20Chronicle/Engine%20and%20Drivetrain/DCP_1732.jpg

So is my elbow not sized right, or is it the water pumps?  Do I have to buy this pump for it to work?: http://www.rickscamaros.com/camaro-water-pump-302-small-block-date-coded-1967-1968.html

For my rules, the water pump doesn't have to have the factory date code stampings, it just needs to be equivalent in performance (weight, water flow, etc.).  But it for sure needs to accept the correct bypass elbow! 

Any help the folks here can offer is much appreciated!!!

--Jason Rhoades

6

Trans-Am Camaros / '67-'68 Penske Camaro Sunoco Blue

« on: May 16, 2011, 07:59:11 PM »

Hello,
I'm sure this has come up before, but I'd be interested to know if anybody has the inside scoop on the "Sunoco Blue" used on the original Penske/Donohe Trans-Am Camaros.  I've got just about every book and read every website out there.  Even found a number for "Molin Auto Body" in PA where they were originally painted (no longer in business).  As best I can tell "Sunoco Blue" was actually several different colors over the years, depending on the car, which shop was painting it, what Sunoco specified as their blue at the time, etc.

I took a pic last August of the '67-'68 cars at the Monterey Historics last year: 


My car is in the body shop now, and I like the darker blue of the car on the left (#15), not the lighter blue (#16).

I actually like this blue even better, but I can't tell if maybe it's just it being an old photo that makes it look so dark:


So I guess what I'm looking for, is if anyone here has any insider info on the paint codes, or shops, that graced these cars, such that I could do a fitting reproduction.  I've done lots of looking at GM factory paint codes and such, it's tough to find anything that isn't a metallic of some sort (which these are not).

Thanks again to the awesome Camaro Brain Trust!!! 

7

Originality / Carb jetting for '67 Z/28

« on: May 05, 2011, 05:21:37 AM »

Hello,
I'm the crazy guy building a '67 Z28 clone to autocross with the SCCA (http://www.rhoadescamaro.com/build).

One thing I'm curious about, is what was the original carb jetting in the car in 1967?  I have all the factory manuals, but none of them mention it, at least not in the engine sections.

In the 1968 manual, I've seen it specify #68 primaries and #76 secondaries, same jetting as the SS396.  Does any documentation exist showing jetting for the '67 Z?

Other thing, does any of the factory documentation (not race prep guides, but service manual type stuff) prescribe any sort of jet changes?  An example, maybe for customer cars at high altitude?  Haven't seen it in the books I have but maybe I don't have all the right ones.

Thanks again to the super Camaro brain trust!!!

8

Restoration / Rec. source for door and interior parts?

« on: October 05, 2010, 07:12:15 PM »

Hello,
Getting into the restoration on my '67 coupe.

The car's passenger door is perfect, it opens and closes like new.  I see on the door itself, a big GM stamp pressed into the metal.  The driver's door however, sticks and rattles, the outer skin wobbles, it's a mess, no GM stamp.  I can see inside a sticker, I think it said "Classic Industries".  Considering the lack of the GM stamp on the inner portion, I'm going to guess the whole door was replaced - does Classic Industries make a good door?  At this point I can't tell if it is a good part put together poorly or just a bad part.  Is there a replacement door I could get that matched the quality of the OEM door?  Or somewhere with NOS stuff?

I also need to replace pretty much the whole interior, and all the wiring.  Everything I have now is stinky, worn out, or both.  I'm not as finicky on this stuff as I am on the door, but would like suggestions for a place that offered good value for those components.

Oh, last thing - how do I get the window crank and door latch pulls off?  I've got the whole drivetrain out and front half of the car in pieces, but I can't figure out how to get the door panels off... 

Thanks!!!!!
Jason

9

Originality / 1967 Z28 questions

« on: March 24, 2010, 07:09:35 PM »

Hello everyone.  First post, apologize in advance for its novel length-

I am currently in the research phase for a project wherein I intend to construct something of a Z28 clone.  Not to try to pass it off as real or make money or anything, but to race!

As some personal background, I am a die-hard autocrosser with the SCCA.  I've been competing on the national autocross scene for about 8 years now and in that time have managed to win a couple championships.  The thing about me though, is I like to put together cars nobody else thinks to try.  I've beaten Mitsubishi Evos with a Lexus IS300, Honda Civics with a Nissan 240sx, and at the moment I'm the only guy campaigning a Viper against Lotus Elises and Porsche GT3s.  My plan is to build a '67 Z28 to beat up on non-M 3-series BMWs and Mazda RX8's.  There are some other cars that might be easier or less expensive, like a Fox Mustang or an early 90's Firebird 305, but I really like the first gen Camaros and am a ridiculously huge Mark Donohue fanboy.

Autocross has a lot of different preparation levels, or categories, from Stock, all the way to "Modifed".  The prep level I'm interested in running the Camaro in is the first level up from Stock, called "Street Touring".  This class allows only some very basic modifications to the car, much less than what's being carried out by the "restomod" folks.  Our rulebook is here if anyone is interested:
http://www.scca.com/documents/Solo_Rules/2010_scca_solo_rules.pdf

The Street Touring category has a few classes within.  The reason I'm interested in the Z28 is because there's a class (STX) explicity for 4-seat cars with engines up to 5 liters.  Just like in Trans Am! 
As a quick summary, in Street Touring we can change the seats to race seats, we can change the shocks and springs, but have to keep the same spring type.  We can change wheels but are limited to 9" in width, and street-compound tires 265mm wide.  We can change sway bars, and add a panhard or watts link.  In double wishbone suspensions, we can change the upper or lower arms, but not both.  We can replace the suspension and drivetrain bushings, as long as the replacements are not metal.  We can upggrade the brakes to 4-wheel disc and put in a limited slip differential.  On the engine side, we can do headers and a exhaust, and can change the air filters, but that's about it.

The thing about SCCA is their, "if it doesn't say you can, then you can't" rules style.  So all the tricks and tweaks and subtle modifications people usually do (Guldtrand mod, gear ratio changes, porting, cam changes, etc.) aren't legal.  The car would need to have a DZ302 with bone stock internals (engine can be first overbore, but not to exceed .020").  The interior would have to be stock, though we can can upgrade steering wheel and shift knob.  The exterior would also have to be stock, no flaring or cutting.  While the VIN plate doesn't have to specify the chassis as a Z28, everything about the car has to be just as it would have been in 1967, but for the above modifications.  That's what brought me to the "originality" subforum here.

The reason I'm interested in a '67 Z28 is because it could be ordered in a way that faovors this ruleset.  We are not allowed to remove smog equipment, so I'd have to run the smog pump on a '68 or '69.  It also appears as though the car could be ordered without a heater in '67 only, which would be a big weight savings - yes, I am crazy, though I also live in San Diego and  would trailer the car to far-away events.

I can't swap parts between years of Z28, so none of the fancy '69 parts can be used.  Can't use "trunk kit" or dealer installed items either, like cowl induction or the later crossram carb setup.

So here's where I get to finally asking a couple questions-
First, while we can't swap parts between years, we can leverage factory part "supercedence".  This is where the factory revises a part somewhere along the line, and specifies the new part in replacement of the old. Specifically in regards to the DZ302, does anyone here know if the later 4-bolt large-journal block was ever issued as a superceded part for the old one?  For instance, if the year was 1970, and you owned a 1967 Z28 with the original motor, and blew it up while under warranty - when you took the car into the delaer, would the dealer put in another 2-bolt block, or would they give you the revised '69 unit?  This  stuff is all so old now, tracing parts supercedence through old parts books or fiches might be hard.  The reason I ask of course, is it would be much much easier to put together a "stock" 4-bolt DZ302, as so many more were made.

Second question.  I've actually purchased the factory assembly manual, chassis service manual, and the Body by Fisher manual for 1967.  The thing I've found, is the service manual completely leaves out any reference to the 302 motor. My other concern is whether I will be able to tune the carb for the right mixture with the free-flowing headers and exhaust.  We don't have any explicit allowances to re-jet, we can only make adjustments prescribed in the factory service manual.  The manual lists jet sizes for all other motors, but not for the 302.  If I am protested, I need to show that the carb setup is stock, tuned within the factory tuning range.  Is there a separate manual that lists the standard jet sizes, and tuning procedures, for the 302?  I suspect the '68 and '69 manuals do, but it would need to be applicable to '67.

Thanks in advance for everyone's help.  This site is a great resource! 

--Jason Rhoades