Messages

31

Restoration / Re: .030 over pistons for 302: specs/supplier?

« on: March 11, 2020, 09:47:23 PM »

After much discussion with my local gurus, we ordered a set of .030 over JE forged Pistons PN#202890 described as a 302 SBC 10.4-1 Dome, for Rings we ordered the J103F8-4030-5 which are 1/16 - 1/16 - 3/16 .

I know these are not 11-1 but the consensus is that at 10.4 we can, carefully, run pump 93 and not jeopardize the motor...will have to experiment with the advance curve and if we need to continue to run some of the 110 race fuel as we're doing now, so be it. I don't know yet how deep in the hole these JEs will be. Don't want to end up with anything more than 11-1.

Over the weekend we scored an Eagle forged 3" stroke large journal standard, 2 piece seal, crank at an extremely good price. It's at the shop now for fluxing and miking to see if it needs to be turned.

Still no decision on the cam configuration: how tight the LSA can be without a vacuum deficiency at the booster is the question. Can anybody chime in?

paul

32

Restoration / Re: .030 over pistons for 302: specs/supplier?

« on: February 26, 2020, 04:51:00 PM »

While I'm at it, we are looking at the LT1 cam rather than the '69 30-30....I've always tightened the LSA for SBC's unless there was a critical need for vacuum. I see an LSA of 116 on the current "repro" cams.  First, gotta find the pistons, then gotta find the cam or have it ground...was thinking no more than 110 LSA. I built a 383 with a hydraulic roller in it at 112 which gave me good vacuum for the brakes once the revs came up to 1100...This car will not be driven on a daily basis but we want it to have the crispness of high compression and quick-response cam timing when we do pull it out of the garage or cruise into a show.

paul

33

Restoration / .030 over pistons for 302: specs/supplier?

« on: February 25, 2020, 10:57:04 PM »

We are rebuilding the engine in our '69 Z....We have a .010 overbore block which is correct for the car...but the clean up bore will be .030 over. Can someone advise on the best pistons I should buy? Want to stay at 11-1, floating pins, 4.030 bore, 3" stroke

Rings ductile iron? .062 top and bottom; .124 oil?

Thanks

paul

34

1969 - Orphans / Re: 19N688260 - V0725DZ is in our Z28

« on: January 31, 2020, 09:30:58 PM »

VIN ....658489 is June car.

Here's pad:

Here's a head:

Ooops...indeed K is November:

Paul F.

35

1969 - Orphans / Re: 19N688260 - V0725DZ is in our Z28

« on: January 24, 2020, 09:18:03 PM »

Heads are Dec. 68. The pad stamp - V0725DZ - is clear as a bell. The filter boss stamp is a little tougher: that 260 could be 268 or 288...very indistinct stamping. Pad does not give any indication of block having been decked.

Neither block nor heads is correct for this car. It is a June car - delivery date of June 16 according to NCRS files. That's why I posted on the Orphan site.

paul f.

36

1969 - Orphans / 19N688260 - V0725DZ is in our Z28

« on: January 24, 2020, 05:29:39 PM »

Our VIN is 124379N658489. The engine in the car (an X33D80) is an 010 block, 4 bolt mains, original pan, July 25 assembly and 19N688260 VIN stamp (as best we can tell). The heads are 186 cast one day apart (K18 and K28).

The engine has a rear main oil seal leak and quite possibly a minor head gasket leak. We are planning to pull it and rebuild but I would prefer to rebuild a correct cast date block, leaving the pad unstamped after decking.

Our schedule is mid-February '20 for the removal and disassembly. It would be wonderful to find the at-birth block and supply this one to its rightful car.

paul f.

37

Restoration / Re: Wiring Console Gauges' 69

« on: December 02, 2019, 08:00:09 PM »

I used that ground wire as the bridge wire between the backing plate and ground stud of the fuel gauge. There is another ground wire from the assembly to the body at the trans tunnel. I am using  the front shifter boot retaining ring screw for that ground.

I put the assembled units in the car without mounting the console top. Everything seems to work properly although the tank sender may be off a little. At 7 gallons it's showing 1/4 tank....and it goes from full to slightly less than 1/2 really fast...the water temp gauge is at 1/4 scale at 160* (thermostat is a Stewart 160*). Our weather has been cool this past weekend and the car, with all the new cooling system components, didn't budge over 160* even after idling for almost 30 minutes. I used my laser thermometer to verify that temp.

I'll drive this thing around for a few miles and make sure all the circuits are working as intended before the console goes back together...I figure with it out I can get some stuff under the dash handled....another "as long as I'm here" opportunity.

Thank you immensely for your help and feedback. I hope I can reciprocate as I learn more and more about Camaros. I did a build out of a '69 in 1982 with my then 15 year old son. That was a combination parts car, junk yard and previous builds' leftover-parts rebuild with the heavy labor in engine and trans swap and body prep for a MAACO paint job. That was the last time I raised a wrench to one of these cars until this one.



We've done NCRS Corvettes and many Tri-Fives, the last one being a '56 9 passenger wagon resto-mod - hence the username. That car went through 5 different engines in 10 years as we played with its look - from street cruiser to street racer to an NHRA-legal Modified Production configuration and back to street cruiser.

STREET: 383 cu in hydraulic roller TH350 3.55 Moser 9", TH350




NHRA F/MODIFIED PRODUCTION CONFIGURATION: 327 cu in - 10.5-1, 30-30 flat tappet, '72 Tunnel Ram- 450cfm Holleys, 4.10, TH350





Our goal is to finish this legit Z to achieve as high a level of restoration as possible under AACA judging standards, which are fundamentally cosmetic: not code, stamping or casting specific as are the judging matrices of NCRS and ACA. If we are off in dates from one exhaust manifold to another  but are functionally and appearance correct, we'll be happy.

Thanks again.

paul

38

Restoration / Re: Wiring Console Gauges' 69

« on: November 28, 2019, 03:28:42 PM »

Rich:

Here's what I've got...following your photos plus searching the forum and gathering every piece of literature I could find...







I think it's right. I hope it's right. I am concerned about the resistor on the water temp gauge....I think that may not be correct.

paul

39

Restoration / Re: Wiring Console Gauges' 69

« on: November 28, 2019, 03:26:34 AM »

Thank you for the photos. They are extremely helpful, especially the originals.

 I seem to have original gauges but have ordered a replacement ammeter and water temp gauge. I don't know whether my new temp gauge is internal resistor-equipped or not. Other than calling the vendor is there a test I can run on it to know?

Happy Thanksgiving! (I'll be in the garage immediately after my post Thanksgiving Dinner nap....)

paul

40

Restoration / Wiring Console Gauges' 69

« on: November 27, 2019, 04:19:12 PM »

Can anyone give this idiot either pictures or explicit directions for the wiring connections on console gauges on my '69....

I have the AIM, the Jim Osborn '67-'69 wiring diagram manual (which is nothing more than the AIM).

But I am definitely confused as to the resistors, insulators, low fuel warning system....I was truly stupid and took no photos as I disassembled the cluster to install two new gauges and restore the cluster.

paul

41

Maintenance / Re: 186 heads - rocker arm studs

« on: November 16, 2019, 02:43:37 AM »

For racing purposes, there's no discussion... that's the topics over in TC.    Here in TC, we discuss originality (for the most part).. keeping cars original (or at least original looking). 

PS.  I don't think many of us with original 69 Z28s are going racing with them nowadays..

In your experience, do internal engine modifications to improve performance and longevity impact the value of an original engine in an original car? That would include the aforementioned screw-in studs, pushrod guide plates, stainless valves, matched ports, blueprinted cams, etc.?

paul

42

Maintenance / Re: 186 heads - rocker arm studs

« on: November 14, 2019, 04:48:34 PM »

Thanks for the response...that helps in the planning/budgeting of the build.

We'll machine the bosses for the studs plus an extra 1/8" for the pushrod guide plates - and elongating the pushrod slots in the heads slightly.

This block is a July 25 stamped DZ. Ours is a June 18 car. Does anybody have a good block with an April or May casting and DZ stamping? As long as the engine is out, may as well find a more realistic date. I DO NOT RESTAMP and will always disclose the reality of the car, i.e. the M22 is an all-new transmission built by Riverside Gear in Eaton Rapids, Mi and stamped to match this car.

All Corvettes I've done have been matching numbers cars and any restamped elements (including blocks) were always disclosed to the buyers.





Do internal improvements to a DZ engine impact the perceived value of the car?

paul

43

Maintenance / 186 heads - rocker arm studs

« on: November 14, 2019, 03:44:04 PM »

Please spare me the effort of removing a valve cover: are the 186 heads equipped with screw-in rocker arm studs? Memory fails me.

Mine are Dec 1 68 and Dec 2 68...




Thanks

paul

44

Restoration / Re: Drive shaft specs - 69

« on: November 07, 2019, 06:08:38 PM »

In removing the old rear shaft yoke and welding in the new one, we lost 1/4" in total length which should not make a difference. However the exposed input yoke measures 2-1/2" from tailshaft to front of yoke.

45

Restoration / Re: Drive shaft specs - 69

« on: November 06, 2019, 08:59:25 PM »

Thank you, gentlemen. I failed to use the search function here effectively. But is the length of 49.56" from center line of the U-Joints?

I think a buzz/vibration I have at any cruising speed is directly attributable to either the seemingly shallow penetration of the yoke into the tailshaft or a need for slightly more pinion angle. There was a significant vibration prior to replacing the entire rear yoke and balancing the assembly. Additionally, I found that the pinion angle was off by a minimum of 4*. I used 4* wedges to bring the pinion angle into spec and have 6* wedges to add another 2* before I go order a replacement shaft.

paul