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Messages - j-rho

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1
Trans-Am Camaros / Re: Street T/A
« on: April 11, 2013, 04:29:59 PM »
Heyward Wagner, the SCCA's communications director, was out at the El Toro Pro Solo last weekend. While there he put together a very nice little documentary piece on the Camaro.

http://www.youtube.com/watch?v=meybtwmMxQY

Enjoy!

2
Trans-Am Camaros / Re: Street T/A
« on: April 03, 2013, 05:16:18 AM »
Didn't know where else to post this, but thought I'd share, since you guys have been so helpful to me in the process of building and restoring my car-

Car had its first race weekend over Easter.  Slower than I would have liked but it mostly held together.
http://www.rhoadescamaro.com/build/?p=1845

Also have an in-car video for download, it is somewhat large though (~180MB):
http://www.rhoadescamaro.com/build/wp-content/uploads/2013/03/sdTourDay2Run2.mp4

A long way from where it needs to be handling-wise, but now the fun of tuning and setup can really begin!

3
I took a look at your page...correct me if I am wrong however, the carb appears to have the small accelerator pump on the front bowl. If this is the case, the first order of operation is to get the carb back to a base line with stock components, it would be best if you had access to a chassis dyno in order to tune the engine optimally. If you decide to go this route, have your jet sets, distributor weights lined up to minimize your change out times... you will probably find optimal power if you tune the car to about a 10-11:1 air fuel ratio. 
If you are autocrossing use jet extenders in the carb to prevent starving the engine and leaning it out...
Hi James,
The accelerator pump is stock for that model.  The class I race in, only allows factory-specified tuning changes, so unless I can find documents stating otherwise, have to stick with the factory jets, accelerator pump components, and vacuum secondary spring.  What I'm seeking to find out, is if there was ever a factory document of any kind, that specified or authorized a jet or other internal carb change, for any reason.

4
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!!

5
Maintenance / Re: Advice for tuning a stock-ish 302
« on: January 07, 2013, 04:59:09 AM »
It's a long story Jon, but a jet allowance isn't likely to happen.  Some conversation on the topic in this thread (http://www.roadraceautox.com/showthread.php?t=31235) from another forum.  Warning - that site tends to get a bit "salty" as compared to here ;)

The short version, is I'm running the car in a category and class built for modern cars, where the rules makers don't really want a car like mine to do well.  There are other categories to race old musclecars in, where you're allowed to change carbs and cams and pistons and stuff, but those classes also basically require you to cut up the car and run monster wheels/tires, in addition to going much further with race prep than I really care to. 

Have to make the best of the allowances available.  Of note, factory authorized tuning procedures are OK to perform - I've thought about running the float level extra high to increase the static fluid pressure on the jets a little.  In combination with the a jet extension fuel slosh tube, maybe that could work?

6
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    ;D

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!


7
Trans-Am Camaros / Re: Street T/A
« on: December 22, 2012, 07:58:10 AM »
While not perfectly streetable,  this build would make a great pattern for someone trying to replicate an early TransAm Camaro...................

http://www.rhoadescamaro.com/build/?m=201211

BTW........I don't post much here but am a daily reader and fully enjoy the postings from all of you.

I hope everyone has  a safe and Happy Thanksgiving
Just found this, cool thread, thanks Rick!

Building my car into something like a streetable T/A clone, to race with the SCCA.  The class I'm building for has pretty strict rules.  Engine is a stock (rebuilt) 302, stock carb, stock trans.  4.88 12-bolt, upgraded 4-wheel discs, upgraded springs/shocks and leafs, race seats and steering wheel, but otherwise stock interior.

Not allowed to alter smog equipment, so I'm building a '67, where it was available with no smog.  Also heater delete.  Very curious to see what it will weigh!

Only a couple weeks away from having it running.  Made progress since this pic (lowered rear, raised front, installed vent windows), but it's the best I have on its vintage TA wheels.

8
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!!

9
Restoration / Re: eBay '67 Holley Z28/L78 carb
« on: October 30, 2012, 03:26:31 AM »
Other than the fact it wasn't made when it says it was made, what are any other likely differences?  Anything that would make it perform any differently than an original well-maintained carb?

10
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)

11
Restoration / Re: Source for Z28 water pump?
« on: August 24, 2012, 05:21:12 AM »
Thanks again for your help guys (and gals?) - have the water pump going now, am on to the fan.

I found (here, and in Jerry's book) that the car would have been equipped with an 18", 5-blade, 4-rivet fan, with 3.25" diameter bolt spacing where it mounts to the fan clutch.

I found a replacement 3.25" fan clutch.  I haven't been able to find any kind of replacement fan to fit it.  Bought the nicest looking new 5-blade fan I could find, and it's clearly for the 3" diameter fan clutch mount.

Does anybody make a replacement fan that will fit my 3.25" diameter fan clutch?   Or would I be better off finding a 3" clutch for my 5 blade fan?
 
Trying to be as technically correct as possible, without spending $xxxx on original eBay stuff.  As long as the parts I use are no higher performing than stock, I should be OK.

Thanks again!!!

12
Originality / Re: Carb jetting for '67 Z/28
« on: August 17, 2012, 04:34:47 AM »
Sorry for bringing this back up...

Jerry, curious how you know the base Z28 jets?  Just from taking them out of original cars?  And was 68F, 71R, just for 1967?  The manuals I have say the '68s were 68/76 - and the "Project Camaro" article from the back of your book (4th edition) even has the words "...and standard .076" jets in the secondaries..."

The car will be used primarily at sea level.  I can change jets, if the factory every provided documentation showing this was a standard procedure, but I haven't found anything like that.  Are there any special factory carb tuning documents that were provided to dealers?  Obviously racers know how to do this stuff on their own, but I'm in a weird class where I'm not allowed to change jets unless it was a factory authorized/documented procedure.  Also in a bit of a pickle, because I'm not 100% what the stock jets are, or if they even would have been the same between a car sold in Southern California, and one sold in Denver.

13
Restoration / Re: Source for Z28 water pump?
« on: August 16, 2012, 10:15:40 PM »
Thanks for the responses fellas.  Paul, that link was interesting hadn't come across it.  That the factory might have issued the car with a reducer bushing, means I can too.  I have Jerry's book but didn't see that mentioned, will have to look again.

14
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

15
Trans-Am Camaros / Re: '67-'68 Penske Camaro Sunoco Blue
« on: September 02, 2011, 05:25:51 AM »
Wanted to thank Jon Mello again for the help in sourcing the paint codes.  Unfortunately my body and paint resource wasn't able to turn those values into a paint we could use, but I am still sincerely thankful.

After lots of research, I ended up using a factory Porsche color from 1971, known as "Dalmation Blue".  It has a little purple in it, but I think it's pretty much just what I was looking for.

http://www.rhoadescamaro.com/build/?p=1104

Cheers!


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