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  #76  
Old 30-07-2015, 07:03 AM
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Wot Steve says about air boxes makes sense,I was trying to explain to someone with a zed who isn't a member and the best way I could explain went like this. if you fart in a lift it is sort of rammed up yer nose and not dispersed so you get more of it but if you fart in an open field a lot of it gets wasted and blown away so you get less of it.he understood wot I meant,just goes to show we ain't all technical minded it's just some times hard to explain things,think Ram air Suzuki 250
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  #77  
Old 30-07-2015, 07:32 AM
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SeanDezart SeanDezart is offline
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Is that why you live in a bungalow ?
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  #78  
Old 30-07-2015, 01:55 PM
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I live in my country residence,converted pig sty
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  #79  
Old 30-07-2015, 02:26 PM
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Quote:
Originally Posted by SKiddell View Post
Did you get the leak down test done ?

Flawed logic I'm afraid, 25 degrees of error could result in many mm of lift depending on the part of the lobe engaging the cam finger.... valve pockets are not very deep (2/3mm at best)
Not that Steve needs my confirmation, but yes, piston cut-outs don't stop it being an interference engine.
https://en.wikipedia.org/wiki/Interference_engine
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  #80  
Old 30-07-2015, 02:48 PM
bluejon bluejon is offline
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Not sure if this is useful info to this thread but I have some more info on the rebuild to engine carried out in Canada

I have triple Hitachi SU carbs feeding an L28 block bored to 3 litres and matched to a 240z’s E31 cylinder head, ported and polished. Valves are from a 280z and with Toyota R20 pistons shaved to flat head. The crankshaft is 240z (stroked) and connecting rods are also 240z, giving a 13:1 compression ratio.

The camshaft is reprofiled to a .500 lift and .280 duration. Finally a lightened flywheel and oversized clutch and custom 6 branch exhaust/headers.

So far, I've not experienced any engine run-on.

If you are interested I have copy to share of a 'Z Car Magazine' feature on a similar build, indeed a friend of the guy who owned my car which is also mentioned in the article.

* don't ask me any technical questions off the back of this info, because it is all I know about the build so far, and me non-technical (though learning fast!)
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  #81  
Old 30-07-2015, 04:04 PM
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SeanDezart SeanDezart is offline
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13:1 ?
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  #82  
Old 30-07-2015, 04:17 PM
SKiddell SKiddell is offline
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Quote:
Originally Posted by zedhed View Post
not yet - ran out of time - and yes that's what I'm afraid of - but I'm ever the optimist...

when you say error I'm assuming both retard and advance are equally risky?
Advance or retard is equally problematic.

Quote:
13:1 compression ratio.

The camshaft is reprofiled to a .500 lift and .280 duration
13:1 is agressive given the fairly modest lift and duration but if I remember the E31 head had a more pronounced kidney shaped chamber which should help manage the quench better than an overly skimmed E88 or 42 which at 13:1 would go into det on an agressive build (been there )

Quote:
Not that Steve needs my confirmation, but yes, piston cut-outs don't stop it being an interference engine.
No worries, yes the L series is classed as an "interferance engine" IE the valves and pistons occupy and share the same space

Last edited by SKiddell; 30-07-2015 at 04:23 PM..
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  #83  
Old 30-07-2015, 04:52 PM
bluejon bluejon is offline
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Quote:
Originally Posted by SKiddell View Post
13:1 is agressive given the fairly modest lift and duration but if I remember the E31 head had a more pronounced kidney shaped chamber which should help manage the quench better than an overly skimmed E88 or 42 which at 13:1 would go into det on an agressive build (been there )
I think you are right ... I found this
http://datsunzgarage.com/heads/
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  #84  
Old 30-07-2015, 05:55 PM
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Quote:
Originally Posted by SKiddell View Post
13:1 is agressive given the fairly modest lift and duration but if I remember the E31 head had a more pronounced kidney shaped chamber which should help manage the quench better than an overly skimmed E88 or 42 which at 13:1 would go into det on an agressive build (been there )
Blimey, didn't realise it makes that much difference - my E88 was pinking like a good 'un at just over 11:1. I should probably get on with my P90a head then if we can get up towards 13:1
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  #85  
Old 07-11-2015, 10:46 AM
Paul Henley Paul Henley is offline
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Hi Nick, just been going through your thread (although I skipped a lot of the technical jargon which was already leaping over the top of my head), just interested to hear if you have an update? How's the car/engine now?
Cheers
Paul
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  #86  
Old 12-04-2017, 08:18 PM
franky franky is offline
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Hi, Just wondering how you got on with this?
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  #87  
Old 20-04-2017, 07:59 AM
zedhed zedhed is offline
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Hi there, sorry for the delay been so busy!

Happy to say after extensive checking it turns out there's no damage to the valves or engine - a narrow escape thanks to the valve pockets in the pistons I think. The engine now runs as it more or less should but probably needs a little more tuning up.

With regards to the missing parts I did get the Jag carbs back but not the rest. Damage to the paintwork and dents to the wing tops were sorted locally. No point in chasing a company thats gone pop anyway.

I've learnt my lesson - check the credentials of any company working on the car carefully and talk to more of their past customers before parting with car or money, not just one or two.

As for the engine builder Eiji at Datsun Spirit - he's been great and helped me reverse the changes - and I learnt a lot in the process.

The engine is quite the beast - I haven’t had it on the rolling road for a proper power test but I think I need to upgrade the drivetrain lest something breaks.
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  #88  
Old 20-04-2017, 08:55 AM
franky franky is offline
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Good to hear it's back and running. Hope it hasn't dented your enthusiasm too much.

Sorry to hear about the zfarm stuff. You know they're trading under a new name?

What was the story with the engine, what was changed thAt caused issues?
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  #89  
Old 20-04-2017, 01:39 PM
zedhed zedhed is offline
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Franky you can read the long thread if you like. It's epic

What's the new trading name then?
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  #90  
Old 20-04-2017, 04:24 PM
franky franky is offline
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Quote:
Originally Posted by zedhed View Post
Franky you can read the long thread if you like. It's epic

What's the new trading name then?
ZFM motorsport

https://beta.companieshouse.gov.uk/company/09224202
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