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HybridZ

Vacuum cannister or pump?


pparaska

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O.k. The cam's a bit on the lumpy side :D

(236/240 @.050 in a 9.7:1 327)

 

9 in/Hg vacuum at idle ain't enough for power brakes.

 

But I'll keep it in there for the time being.

 

So the question is, are vacuum can's good enough? I've heard they sometimes help, and sometimes don't

 

Or should I go to an electric vacuum pump? Whose?

 

TIA,

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Duh! I didn't know 280ZX's HAD vacuum pumps!

 

Anybody got one?

 

I just won a bid for $21.57 on a Yamaha cruiser's cruise control vacuum pump on ebay. I have no idea if it'll work, but I can give it a shot.

 

Thanks!

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Ross, I wish you lived closer so you could come and tune my Z. You are spot on. I installed the 600 vac sec that I rebuilt and I get more like 14 inches of vacuum at 800-900 rpm. But with the A/C on, the idle drops a to around 650 rpm and the vacuum goes down to about 9-11. I know I could bump the idle up, but I don't want a 1000 or 1100 rpm idle if I don't have to. Who knows where I'll end up with the 650 DP carb :D .

 

The key here is that I really ought to put a solenoid on the thing and have it bump the throttle plates open when the A/C is on so the idle doesn't plummet. I'll work on that.

 

The need for more vacuum is kind of sketchy now. I'm going to try that vacuum pump from the Yahama cruiser and see what happens. If it can give 16+ inches (don't know if it's big enough to do that to a brake booster vice a motorcycle cruise control diaphram), and improves the brakes at idle, I'll be happy.

Heck, I might just have air in the brake system.

 

Thanks for all the help!

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The L28ET has vacuum modulators and the assy may have a reservoir (canister) function as well, the 280ZX does have a vacuum pump and tank (both na and turbos) but it's for the cruise control. It's located on the rt forward fender well. It could probably be adapted for supplementary vacuum for other uses. The LD28 has a serious vacuum pump built into the back of the alternator and gets its own oil supply and drain to the pan. DAW

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So do the 280ZX's have vacuum pumps or cans, or both?

It's been years since I worked on the pre Datsolet OEM NA L28 and even then I did the timing chain and a few others things but memory is still faint. Only diesel's typically have vacuum pumps (electric ones to boot) that I'm aware of. I'm not very informed on turbo's but still can't see the need for a vacuum pump on a 280ZXT. Guys often pick up parts yard electric vacuum pumps (or new) from diesels or install the cannisters you're talking of.

 

I believe Bradman was thinking vacuum boosters.

 

Pete, is that typical vacuum you should expect for our setup? I know you have some tuning too sort out so perhaps you'll finish off with more vacuum once dialed in? Just wanting your vacuum solution to fit your final 'tune' smile.gif

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