Samuri back home.

Al Douglas

Al Douglas

Club Member
The Sam has been away for the last 3 weeks or so having one or two issues sorted out.
On the run to and from Donington it transpired that the carbs were icing up (yes it was bloody cold!).
To that end its been at Car Craft Scotland in Broxburn in the hands of Neil and Catriona Jeffrey and the team.
100 feet of exhaust wrap, thermostat fitted!, new KnN filters, hydronic adjuster rod for clutch replaced, braided fuel lines, carbs balanced and MOT,
I now have constant engine temp, brilliant progression and really sharp, crisp throttle response. Bloody thing is going like you know what off a very shiny shovel.
So good to be back in it. :devil:
Discussing with Neil the option of breaker less ignition. Any thoughts?
That aside its good to see some Z's coming on the market at the moment and following with interest.
 

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I don't think the exhaust wrapping would make any differance to the carbs icing??:confused:
Sounds like your carbs etc needed just some serious sorting out.
Braided fuel lines a good idea.
I have driven my zed when it was -5degrees and it still ran ok!
I use a pertronix ignition in my car for the last 3 years and it has been fine.
I had an issue with the engine not reving past 4000 on holiday this year it was only when the car was mega hot in a 40grees in the shade, not sure if it was the coil overheating or the pertronix though. Never had the issue in the UK though.:cheers:
 
Discussing with Neil the option of breaker less ignition. Any thoughts?
Click to expand...

3 options

1. 280ZX distributor
2. Aftermarket electronic (Pertronix etc)
3. Distributorless....Megajolt etc, uses neat electronics and triggered coil pack(s)

Without doubt I would go breakerless, I cannot understand why not as there are no downsides ???

The big debate is do you go to mapped ignition (eg Megajolt etc), its not for everyone as its almost as scary as electric fans.

On another note
Fit a return line with a regulator in it to the setup (hearby ensues the usual debate on where the regulator should go....no debate, for max effectiveness, it SHOULD go in the return line end of)
 
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Steve, is there a plug and play package for distributorless? Is it just the trigger wheel needs some thought/effort?

Wrt the non-debate on return lines, with a bypass regulator, they're designed to be on supply side and although you could probably make one work on the return, I can't see how it would be better?
 
jonbills said:
Steve, is there a plug and play package for distributorless? Is it just the trigger wheel needs some thought/effort?

Wrt the non-debate on return lines, with a bypass regulator, they're designed to be on supply side and although you could probably make one work on the return, I can't see how it would be better?
Click to expand...


Having it on the return side ensures that the carbs are always fed with the correct pressure, if you limit before the carbs you're effectively lowering fuel pressure in the carbs during high demand. That's the way I see it in my head.
 
This is the installation instructions I have for my Aeromotive regulator:
http://aeromotiveinc.com/wp-content/uploads/2014/09/132-0206-0revH.pdf

As you can see, the supply line to the regulator and the line from the regulator to the carbs is effectively a single line with a single consistent pressure, with any excess pressure bled off to the return via they bypass.

That's why I'm making the distinction between bypass type regulators and those like the malpassi ones that regulate pressure by restricting flow.
 
jonbills said:
This is the installation instructions I have for my Aeromotive regulator:
http://aeromotiveinc.com/wp-content/uploads/2014/09/132-0206-0revH.pdf

As you can see, the supply line to the regulator and the line from the regulator to the carbs is effectively a single line with a single consistent pressure, with any excess pressure bled off to the return via they bypass.

That's why I'm making the distinction between bypass type regulators and those like the malpassi ones that regulate pressure by restricting flow.
Click to expand...

You are wise to make that distinction as they are two different animals, Im am refering to the restrictive regulator types

Upstream regulators work but not as effective as a downstream one and a return line because.......

The carbs should be treated as a variable consumer of fuel (revs, power etc) as such a dumb upstream regulator cannot actively antisipate what their usage will be without significant lag and as such cannot regulate down stream pressure accurately without significant hysterisis..... one minute they will be using tickover fuel the next full chat, (and thus the pressure will vary overpowing the float valve) the idea is to supply a constant pressure, there are only two ways to do this, a sensor in the return forming a closed loop system to a reactive valve or.................fit a downstream regulator....

Steve, is there a plug and play package for distributorless? Is it just the trigger wheel needs some thought/effort?
Click to expand...

Pretty much so, megajolt comes in a DIY or pre built setup, add a coil pack or coil on plug, bolt a trigger wheel and sensor on the crank, calibrate and bingo, benefit is a fully mapped ignition system.
 
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pmac said:
Is the bleed off /return line taken directly off the regulator?
Click to expand...
yes that's right. Effectively, I think the floor of the regulator is on a spring holding it shut and when the pressure in the line through the regulator exceeds the set level, the floor opens and excess flow drops through to the return line.
something like that anyway.
 
jonbills said:
yes that's right. Effectively, I think the floor of the regulator is on a spring holding it shut and when the pressure in the line through the regulator exceeds the set level, the floor opens and excess flow drops through to the return line.
something like that anyway.
Click to expand...

So your line to supply the carbs is a dead end line???
 
I think Dean likes to carry spares as he doesn't want to get stuck somewhere. A distributor is small enough to carry around so why not.
 
I think the biggest issue with the carbs icing was the severe lack of engine temp due to no thermostat and the large radiator. Temp needle sat at stone cold bottom when moving but then when stationary the heat from the manifold was effecting the tick over due to too much heat under the carbs. Went for the exhaust wrap to even out that issue and the new thermostat etc means the gauge now sits just over halfway whether stationary or not.
Carbs well sorted and car running beautifully now.
Definitely going breakerless at some point. But for the moment, all good.
 
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