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Changing from leaded to unleaded petrol? Possible?

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Hi guys, couldn't find any other posts asking this (sorry if there is) but can you convert a 75 260z L26 to run on unleaded? If so, how and does anyone know what kind of price bracket that would be in?

Thanks so much!

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L28 already has the hardened valve seats in the head to suit ULP - nothing needs to be converted.

Just fill it up with ULP & drive ;)

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Sorry lurch, I'm a dill, just sold the 280 so had l28 on the brain (what's left of it).. I meant l26.  :-[

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Why not buy some lead additive for your unleaded petrol

 

Or you can get hard valve seats fitted in the head...plus more durable valves than standard ones

 

Other posters might know about more about it for Zeds

 

Pete

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Same/Same - the L26 has the hardened seats too = ULP friendly.

Only the early 240Z's had softer seats which 'may' require an additive.

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Hi guys, couldn't find any other posts asking this (sorry if there is) but can you convert a 75 260z L26 to run on unleaded? If so, how and does anyone know what kind of price bracket that would be in?

Thanks so much!

 

That's funny cause when you edited your post it made Lurch look like he didn't know what he was talking about... and that's Very Hard to do  ;D

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Mwahaha! My work here is done! ;D

 

Hmmm ULP friendly... so would you say that it would be okay to run it on unleaded all the time?

 

Thanks again guys

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I just think choose your fuel carefully and keep it consistent to pick up on any issues.  I'm fairly anal about fuel, keeping all receipts so I can figure out if something is going wrong with its economy. :P  The biggest concern ever is bad fuel, but also keeping your tank near empty, cos of all the potential build up of crap over time that sits at the bottom of the tank.  I am suspect of some of the Caltex fuels around my area and also the independents provided by Caltex which had in the past caused me some troubles (ie. found water in the fuel filter! and inner fuel tank corrosion), but I wouldn't exclusively rule them out at all.  So for a couple of years I've used V Power with additive and I find it just great.

 

Also I can run it on non premium unleaded and/or without additive too but my L20 and L26 Dattos have all been noticeably lackluster as a result of lower octane fuel so I wonder why the L20 is on the register as ok to run on unleaded where the same year L26 isn't?

 

I'm 100% confident leaded fuels of the past (low octane) can be replaced no problem with high octane fuels.  The additive isn't necessary to run but I use it as a safety measure.  The real costs that don't get enough attention are the flow on effects like poorer fuel consumption, increasing engine temp (you should retune your carbs if you're changing fuels anyway), etc.

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Yeah the only major problem with using unleaded is that you need harder valve seats since the lead would lubricate it.

 

As a side note: I also only found out the other day why it was illegal to put leaded in unleaded cars. It was because it would destroy the catalytic converter.

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Same/Same - the L26 has the hardened seats too = ULP friendly.

Only the early 240Z's had softer seats which 'may' require an additive.

 

Interesting

My Aug 76 build 260 Z was definitely was fitted with brass valve seats and I found them to be recessed badly after years of driiving on ULP (even with with using lead replcement additive) ............We installed hardened valve seats when we rebuilt the engine .

 

May be only late L26's (after 76) had hardened valve seats ?............mine definitley did not.

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That is strange.

 

According to research I conducted previously (http://www.viczcar.com/forum/index.php/topic,6012.0.html) the early L26 had a P30 head, whilst the later L26 had an N42 head. The N42 did have the hardened steel seats. Is it possible that the P30 heads were the last L series to use the brass valves?

 

The original owner of my car (74-75 260z) told me to always use additive so I'm going to have to see whether I am running a P30 or N42.

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My head is an E88 on the L26.........as originally fitted (I bought the car with 50k on the clock ...so unmolested.

I too thought it would have hardened valve seats .......until I pulled the head off and was in for a surprise

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Wow, thanks for all your advice guys,  :D I'll get my local mechanic to have a look and see if it has the hardened valve seats- will let you know! : ) ;D

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seven years ago he said she'll be right mate, might have to alter the timing Ho Ho Ho!

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About 7 years ago I had my L26 head reconed and UMR engines told me the same. All ok to run unleaded. I still chuck a bit of Morleys in the tank now and again though to be sure, to be sure.

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