Topics

1

Originality / Any documented z28s w/o black or white stripes out there?

« on: August 06, 2021, 03:15:18 AM »

I ran across photos if that early Maroon/Red car (not sure who owns it, But Id love to)
And i was wondering if we have any documented examples of cars with special order stripe color, or if any Z28 were done with unusual stripe combos like the early Maroon cars

If i read correctly,  black, dover, and cortez silver Non-Z28 could have had red stripes - so I wondered if we have any factory mistakes?

Cheers

2

Maintenance / Z28 - 4053 mods when running the 140 cam

« on: September 21, 2019, 11:30:28 PM »

Other than jetting -
Does anyone have any advice on tweaking a 4053 to run better when the 140 cam is used?
Idle or high speed air bleeds or anything

Thanks in advance?

3

Maintenance / Clutch shudder - tuning wuestions

« on: August 16, 2019, 03:06:21 AM »

Trying to tune out a clutch shudder on take off

Stock 1969 302.  With 1970 Lt1 cam
Manifolds, transverse exhaust
4053 with 72/76 6.5 and 8.5 and a 31 squirter

I don't believe timing is the issue as Ive had it everywhere frok 12initial/36wot to 20/42. With and without vac advance and no appreciable difference

The car is responsive and pulls great for being all corked up. 

The only thing i think is different in my carb,  previously i had 80 or 82 jets with a PV blockoff
And was running rhe 6.5pv up front when I had the 30/30 and it was smooth on take off

With the added 4-5” vaccuum at idle that the Lt1 cam creates, - do i need an 8.5 pv up front?At 900rpm idle, im getting 14-15”hg

Thoughts?

4

Mild Modifications / l88 flywheel in a Z28

« on: July 29, 2019, 04:38:51 PM »

who has done it?
any chatter or shudder on take off?

I have a #30 wheel in there now and a McLeod Super Street Pro and it shakes on take off -  i'm approaching 300 miles on the new clutch -  McLeod says give it 500 miles - but I've driven tons of cars with fresh clutches that were smooth as silk


curious if anyone has tried the lightweight flywheel with a torque-less 302 to see how the take offs are.  My car has 3.73s and M20

5

General Discussion / Stock DZ302 ideal performance....

« on: August 27, 2018, 02:14:06 AM »

Pretty sure I have the car running to optimal performance

You cam literally feel a solid kick in the pants at/around 5000/5200 rpm on up.
Starts pulling at about 3k but really wakes up at 5k
This through stock manifolds

Is this just he secondaries finally opening all the up or just where the 30-30 cam finally wakes up?

6

Maintenance / another 4053 question

« on: August 24, 2018, 12:01:43 AM »

so - I rebuilt the 4053 on my all stock Z, did some stagger jetting, took the car for a spin -she runs absolutely GREAT. BUT i'm concerned about the idle mixtures, and raw fuel odor at idle.

jetting is staggered, 73/71 on the primary with a 6.5 pv,  79/77 on the secondary with an 8.5

with the carb flipped, you can barely see the transfer slot on the secondary side - i err'ed on the side of too little transfer slot showing.

with the engine idling at 950,  (started with the idle mixtures 1/2 turn out where it seemed to run best prior to the rebuild/rejet)

timing is about 20 initial with 38max wot, using full manifold vaccuum,   I have a pink pump cam in the #1 and a 31 squirter -   the car is super responsive, and pulls very strong all the way up.

when I was adjusting the idle mixutres with a vac gauge, i could seat both and the idle went up - backed the curb idle down again, with both mixture screws seated and still get my highest vaccuum reading of over 12-13in - almost got to 15" hg, but that was with the idle around 1050.

what should I be looking for?  I'm to believe that seating the idle mixures means that its pulling fuel from somewhere? or is it pulling air from somewhere?

the bowls have been off several times, so i could see a bad gasket seal - but no obvious fuel leaking, and again, it runs better than ever.

any help woudl be great.

Thanks

7

Maintenance / ideal 4053 jetting for stock 302/30-30/manifolds

« on: August 18, 2018, 08:05:42 PM »

getting my stock DZ302 back on the road this week -  and have a few questions.

i'm getting a high rpm break up - but i think i know where/what that is - as for the carb...
i know 68-72 was stock jetting - but i also know that is WAY lean.

the motor is true 11:1, installed a NOS 3849346 cam with factory - 0-stamped rockers. - lash is set and checked at 30/30 -
ignition is 38wot, with initial around 18 -  car fires up beautifully, and I have no issues with idle at 950.
its got 70-76, with a 6.5 and 8.5 and a yellow spring - and its pretty doggy - even for a gutless 302 with manifolds lol.

one thing that seems odd - idle mixtures are only 1/4 to 1/2 turn from bottomed out with about 10"Hg at idle... so i'm slightly concerned about the mixmatch of new/old Holley parts.

the carb is an old 4053 with original metering blocks, on newer 4053 baseplate -   i still have the rest of the repop 4053 which might get put back together tonight if I can't sort this original out.

something just doesn't seem right about the way it runs - its rather sluggish to get off the line, seems ok mid-range wise - but never really pulls hard.

Years ago, I borrowed a buddy's o2 -A/F tailpipe rig and I got the best readings with 72-76 with the stock manifolds... does that sound right to you tinkerers?

Thanks

8

Decoding/Numbers / date code for 09D 1111480 dist

« on: August 09, 2018, 03:40:11 PM »

need to find a correct dated distributor for a late 69 Z (09D)

may is as late as i've found for the stamps - anyone know of or have a later batch date for a 480?

i'd rather not buy a restamp, but until i can find an original - it might be my only option

9

General Discussion / repop headers for 67-9 Z28

« on: February 03, 2017, 09:54:44 PM »

Anyone know of a reasonable source for these Kustom or Bill Stewart Headers?

HBC has em for about 2k   that seems ridiculous  -

I seem to recall someone saying Larry Christiansen was having them done - but i don't know how to get ahold of him or what the price was.

Thanks

10

Originality / 69 Z28 Exhaust

« on: August 27, 2016, 06:30:04 PM »

According to Gardner and late Z (09D) would have the resonators and transverse muffler.
Waldron exhaust claims that Z28s did not get the resonators. 
I've seen a magazine image of a ZL1 test car with resonators and transverse muffler so i don't think "hi-perf" cars were "resonator exempt"

can anyone answer with certainty?

Thanks

Aaron

11

General Discussion / tire/wheel combo question

« on: May 03, 2016, 12:12:33 PM »

Looking to put larger OE style rubber on my 69 z

Kelsey TIre makes a G60x15 in Polyglass GT -  anyone know if/how well these fit with stock rally wheels and suspenion?

2nd -  the other option would be to put a set of MiniLites on... anyone know where I could get a set?  15x7 or 15x8

Thanks

12

Decoding/Numbers / location of 12bolt axle stamps

« on: February 04, 2016, 01:32:46 PM »

quick question -  i've seen 3-4 Camaro/Nova 12bolts in my day and the stamps always seemed to be on the pass side tube facing forward.... (at least that is my memory at the moment)

were the axle stamps ALWAYS in the same place? I suspect because its probably more accessible when the transverse muffler is hanging in place - - or was it stamped prior to assembly, and just the way it was - or is just odds that the ones I've looked at all are in the same place? 

13

Decoding/Numbers / distributor and 12bolt date codes for a 09D car

« on: February 04, 2016, 12:39:07 AM »

I have an O9D Z28
looking for a date code correct 1111480 distributor, and a 12bolt.

the trim tag is 09D and the engine stamp agrees.

question is - how early could a 12bolt be to be accurate?

and same with distributor? 

thanks

14

General Discussion / white cloth covered resistor wire and factory spade terminal

« on: November 14, 2015, 12:45:37 AM »

anyone know where i can get resistor wire (cloth covered) and the spade connector??

someone converted a car of mine to HEI many years ago and clipped the original resistor wire and subsequently discarded it and the yellow starter wire.... i'd like to restore/replace them without having to replace the entire engine harness

thanks
Aaron

15

Restoration / correct vinyl top glue pattern

« on: November 12, 2015, 03:44:34 AM »

I can't seem to find any info on this -

but every original vinyl top i've seen has a "checker board" pattern visible - which i believe has to do with the way the glue was put on...

has anyone successfully recreated this on a newly installed top?