Starting Carb Conversion: Flat Tops to Paltechs

[siteunseen]

That zcardepot is a Pacesetter, same as ebay. 10 years ago the thickness was short, not good. Maybe better now?

I would wait out msa or go with msds. Msa has theirs built then sent to a coating place nearby called Embee. They could have a batch at Embee almost ready?

Edited February 14, 2021 by siteunseen

[Dadsun]

5 minutes ago, siteunseen said:

I would wait out msa or go with msds. Msa has theirs built then sent to a coating place nearby called Embee. They could have a batch at Embee almost ready?

Yes, Embee is the hold up.  They've apparently had a batch of MSA's 2020 header orders held hostage for a while, so MSA is telling people they are in wait and see mode.  I told MSA to consider Jet-Hot. They've done it a long, long time and are fast turnaround. Took them about 5-6 business days to get mine coated and back out the door. So, that's why I'm thinking just ordering the uncoated from MSA and then sending them off. Just tough to wait around another month or so with a car that is otherwise ready to roll.

Problem is Embee is a drive across town for MSA and Jet-Hot is a shipment to Oklahoma.

Looks like those Pacesetters are sold by ZCarDepot, Summit, and Holley, among others.

[Zed Head]

16 minutes ago, Dadsun said:

 As for eBay, the only decent listings there seem to be the ones from California Datsun. But, apparently he has a bad rep here.  Is it bad product or bad customer service?

California Datsun used to be Datsun Parts Limited.  The guy that owns the business is named Al.  He has a membership on this site as URGELIS.  You can search the name on this site, and the former company name on the internet to learn more about him.  His old business had a bad reputation for selling defective parts then refusing to make things right.  

Notice that he does not really address the major concerns with the headers.  The port shape and the flange thickness.  He does not show photos of either either, just s single photo of the view that doesn't tell much, with a universal shaped gasket. 

Get on to Rock Auto and compare things like distributors with the same parts on his site.  Compare prices.

https://www.californiadatsun.com/headers/datsun-nissan-z-240z-280z-n42-p90-e88-header.html

[Dadsun]

I exchanged emails with Marty (MSDS). His header flange he's been making forever has a 0.5" thickness, which is less than my intake manifold thickness I'm measuring (which is about 0.6"). So, now I'm wondering if I have an unusually thick intake manifold flange? What's the standard?  Maybe mine is standard and MSDS is not thick enough... but Marty has been making it a long time.   :dunno:

I'm thinking MSA is the way to go. 

 

Edited February 15, 2021 by Dadsun

[Zed Head]

11 minutes ago, Dadsun said:

I exchanged emails with Marty (MSDS). His header flange he's been making forever has a 0.5" thickness, which is less than my intake manifold thickness I'm measuring (which is about 0.6"). So, now I'm wondering if I have an unusually thick intake manifold flange? What's the standard?  Maybe mine is standard and MSDS is not thick enough... but Marty has been making it a long time.   :dunno:

I'm thinking MSA is the way to go. 

 

That's only 0.1", not a lot.  I think that the thin flanges are typically 3/8" (.375").

MSA should be able to tell you the thickness of theirs.  It's a big selling point.  They work best if you call them.  Old school guys.

[AK260]

Spotted this earlier - looks tasty but no real history I’m aware of, hopefully someone in the US can comment ....

https://www.ebay.co.uk/itm/1-5-Primary-Datsun-Z-Header-All-Square-Port-240Z-260Z-280Z-280ZX-/313386185058?_trksid=p2349624.m46890.l49292

[Dadsun]

 

5 hours ago, AK260 said:

Spotted this earlier - looks tasty but no real history I’m aware of, hopefully someone in the US can comment ....

That one on eBay shown as coming from Top End is the MSDSinc.com product (aka Marty mentioned earlier in this thread).

Go to Marty's site instead if you want that one. You'll save $60-70 buying directly from him. He has a good reputation on here. I wound up going MSA's product over his but only because they have the exhaust-to-tail connection ready to go. Marty's part number related to that eBay item is HO-241, I think.

[Dadsun]

Ok, I'm back. Got the MSA header, then had Jet-Hot coat it, and also have the MSA performance exhaust system to tie it into. 

The thing I'm most giddy about today is successfully getting off all of the old mount studs. Spent time here and there over the last few weeks with PB Blaster, hammer taps, and good old vice grips. 

So, I'm ready to reassemble. 

My previous efforts here have used the bolts at the intake manifold, not all studs. Any tricks to assembling? I'm thinking I should start only with the studs shown to get the header and bottom of intake manifold in place and a little snug before adding the top studs. 

Edit: ok, I learned the hard way... Set all the studs then get after it. Looks like a good seal across the header. Will crank tomorrow. 

Edited April 3, 2021 by Dadsun

[Dadsun]

Need some insight...

So, the header and new exhaust are in. No leaks as far as I can detect!

Sounds pretty good although I still have some carb tuning to get back to. 

But, I have an issue with the accelerator/throttle linkage. It is tight and requires me to push down fairly hard to get it moving. Which results in a big rev and jerking. I think it's that the two springs connected to the heat shield are too tight. 

See yellow arrow on pic. Any suggestions?

And how do the carbs stay in idle if there is no heat shield and springs?

Also, that connecting rod between the carbs linkage and the top idle screw seems at a less than optimal angle when trying to generate movement downward on the linkage. It'd be better if it were longer, but then the idle would be very high unless I made adjustments elsewhere. 

Any help appreciated.

 

Edited April 6, 2021 by Dadsun

[Carl Beck]

@Dadsun   Here is one answer - http://www.zhome.com/ZCMnL/tech/AccelLinkage.htm

What is the build date on your Z?

 

FWIW,

Carl B.

[Dadsun]

6 hours ago, Carl Beck said:

@Dadsun   Here is one answer - http://www.zhome.com/ZCMnL/tech/AccelLinkage.htm

What is the build date on your Z?

 

FWIW,

Carl B.

Oct 1972

[jfa.series1]

I see that the rod coming off the bell crank is pretty well extended on its adjustment threads. This is increasing the mechanical advantage and adding to the "jerk". You can adjust that rod shorter and soften the response a bit. Softer return springs at the heat shield will also improve the problem, just not so soft that the carbs will not shut down when you lift from the accelerator pedal.