Messages

1

Maintenance / Re: Survey Request -- Z28 302 Cold Engine Starting Procedure

« on: November 26, 2024, 11:55:10 PM »

Thanks for your info, Tim.  Your info on your L88 is applicable to this survey, given those engines had similarly "long-winded" camshafts and big CFM carbs to those found on the early Z28's.  And thanks for mentioning your engine starting process includes waiting 10 seconds after pumping the throttle before turning the key.  I should have included that as a question to ask in the list of survey questions.

Is the carburetor on your L88 a Holley with mechanical secondaries (meaning, it has an accelerator pump on both the primary and secondary float bowls)?  If so, that may help to explain why you’ve had success starting your cold engine after giving it only 2-3 throttle pumps.  I recently had a 413 small block with a solid roller cam that had the same int/exh durations at 0.050" as the ’67-’69 302 cam.  It had a Quick Fuel mechanical secondary 850 CFM carb with no choke system on a dual plane intake.  Like your L88, it would always fire right up after only 3 throttle pumps when dead cold.  The key thing here is that any mechanical secondary carb puts the same amount of fuel into the manifold with only 3 throttle pumps as a roughly equivalent vacuum secondary carb does with 6 pumps.

I am hoping more 302 Z28 owners respond to this survey.  If they do, owners of these, and similarly spec'd, cars will gain information about how they can best be "coached" to reliably cold start in a more consistent manner.

Thanks to all who respond.
Chuck B.

Hey there Chuck,

Yes, the carb on the L88 is a double pumper.

Tim

2

Maintenance / Re: Survey Request -- Z28 302 Cold Engine Starting Procedure

« on: November 12, 2024, 09:13:40 PM »

I'll respond survey prefacing the fact I do NOT have the requested car. Although, I find the procedure applicable to most any collector car I own.
1. Crank the engine until it shows oil pressure
2. Once it shows oil pressure, I stop cranking and depress the pedal to the floor 2-3 times
3. Wait about 10 seconds
4. Crank (no thottle) and most often the car jumps on high idle (or in the case of my L88 I hold it up there).

I find cranking the engine until there is oil pressure is enough to fill a low fuel bowl. Pumping twice and waiting allows the fuel to atomize in the intake.

Tim

3

Original Cars and Details / Re: 1969 Z28 time capsule

« on: January 21, 2024, 11:33:50 PM »

MOAR PLEASE!

4

Maintenance / Re: L78 Rough Idle and Stumbling

« on: December 05, 2023, 06:33:14 PM »

You mention there is a red wire coming from the distributor, as well as a black. That in addition to your comment about a Flame Thrower coil, would suggest there is a Pertronix pick up in the distributor. IMHO, that would be the FIRST thing to get changed out. Others may have different thoughts, but those pick up's have proven to be very troublesome in my experience.

Tim

5

Originality / Re: Preservation of a 68 Camaro

« on: September 09, 2023, 01:14:55 AM »

That car is really coming full circle!!

6

General Discussion / Re: Holley Carb Issues

« on: June 24, 2023, 10:11:03 PM »

Danny,

I'm a bit late to the party for this conversation. Am I safe to assume your carb is full rich at idle? If so, try this. With the carb off of the engine, place it on a carb stand (or some equal length 5/16 bolts that are secured to the base plate to suspend the carb). Fill the float bowls. Does the carb leak down while the carb is sitting there? That would only get exaggerated by engine vacuum at idle.

As you get it off of the idle circut......it runs fine. Of course, engine RPM can cover up some some fuel and ignition problems. If I were a betting man, I'd say the issue may exist with one of the metering blocks / gaskets / and or main body fit. It sounds like fuel is getting in where it does not belong when it's supposed to be working strictly on the idle circut.

That all having been said, I too would suggest reaching out to Eric @ Vintage Musclecar Parts. Eric does ground zero rebuilds above and beyond full restorations. So often, I found out how warped the main bodies are, to say nothing for the metering blocks. Eric recently helped me through an problem child 4150 that was on an LT-1 Corvette. It was an issue as I described above.

I can appreciate yoiu not wanting the bother anyone, nor laying the car up for a period of time. In my own humble suggestion, put a pro on it. You'll save time and aggrevation that you would not otherwise be able to put a price on.

Tim

7

General Discussion / Re: Holley Bowl Gaskets

« on: April 09, 2023, 05:06:01 PM »

Here you go Danny. You'll be set for a while

https://www.ebay.com/itm/403086854325?chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&mkscid=101&itemid=403086854325&targetid=1645685073328&device=c&mktype=&googleloc=1013336&poi=&campaignid=16730423415&mkgroupid=135815925780&rlsatarget=pla-1645685073328&abcId=9300841&merchantid=8002944&gclid=CjwKCAiAk--dBhABEiwAchIwkWHAb6hCnq_-3hnFe-DUlCHIsL_qGlqlQhZexnCow4OGxgOVSPEE0RoC7-4QAvD_BwE

8

General Discussion / Re: L88

« on: January 15, 2023, 10:58:57 PM »

Here is an article about a 1967 Camaro that had a L88 engine installed by Nickey Chevrolet:

https://www.motortrend.com/features/unrestored-1967-chevrolet-camaro-l88-power-transfusion-courtesy-nickey-chevrolet/

I saw this car over the summer. It is specfreakingtacular!

9

Originality / Ground Strap Bolts for a 68 LOS car

« on: November 29, 2022, 10:13:49 PM »

Can someone provide me with a pic of what I am looking for in the for of the aforementioned fastener? These would be for the straps that run from the firewall to the valve cover.

In advance, thanks for your consideration!
Tim

10

Maintenance / Re: Balancing flywheel and clutch assembly together?

« on: November 25, 2022, 02:28:21 PM »

I'm a bid advocate of it, as I HATE doing things twice. You'd be surprised how far off a pressure plate can be.

Tim

11

Originality / Re: Preservation of a 68 Camaro

« on: August 28, 2022, 10:11:19 PM »

Any updates Darrell? As you can imagine, I love your processes.

Tim

12

Mild Modifications / Re: Factory Camshaft spec's for 1967 L48

« on: August 08, 2022, 12:14:19 AM »

OK, dum question time. CNorton said NHRA checked lift with a solid lifter. Can someone explain why, with it being a hydraulic cam?

Checking with a hydraulic lifter would reduce or " dilute" the readings because of it's ability to adjust lash.

13

General Discussion / Re: L78 Values

« on: July 24, 2022, 02:45:34 PM »

PM sent

14

General Discussion / Re: Timing

« on: June 12, 2022, 01:29:30 PM »

Corvette Central has the B28 vacuum cans. I recently bought one for a 65 Corvette 365hp car. The can checked out just as designed. Many of the aftermarket cans do not operate like the B28........they just fit the distributor.

15

Original Cars and Details / Re: 68 L78 Rallye Green

« on: December 01, 2021, 12:26:07 AM »

This car "speaks to me".

Me too!