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Zedman240®

RB25DE into 240Z Conversion.

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Thanks for the reply - your injector plugs and wires are neat - were did you get those? Or did you put that shield over the wires your self. I just have some new plugs with wires on and not a nice looking boot/shield like that of yours.

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Whats happening with this build up?

 

One quick question, where do you get a vac signal to tune such a set up or is it all tps??

 

One more, ;D if you used an rb26 head for example, could you use the existing six throttle bodies and simply purchase and mount efihardware trumpets??

 

I can't wait to hear this thing take off under load. 8)

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Builds all done and running; there's a couple of youtube videos of it running at some club days. As for the tuning, yes, its all done with TPS vs rpm/load.

To use the RB26 throttle plate, I'm not sure if it has injector holes in it or if they are mounted elswhere; Nzeder (Mike) would be the man to ask about that.

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The RB26 intakes have the injectors located at the head end of the manifold. And yes if I had not already had the DCOE throttle bodies I would have stuck with the RB26 throttle bodies with either the stock plenum or trumpets - I would say the EFI Hardware trumpets would fit, might have to make a custom mounting plate - however I could check this out for you in the weekend if you like.

 

I have recently sold my spare RB26 head (going on a RB30DE build here in NZ for a 240k GT repower project) however the guy did not need the intake or TB's as he already had some. So I have a full intake setup from the RB26 if someone is interested - I believe a number of guys have fitted these to RB25 heads with some mods.

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Well, after all the fun I had putting it all together, I've started to do the opposite! Engine has been removed and on ebay and gearbox is next. If anyone is after a RB gearbox (non turbo) I have one available (pending a response from previous inquiry). If I wasn't in such a hurry for cash I would've waited but I can't this time. I've PM'ed but still no answer... Received L28ET distributor last week so I may start a thread if anyone wants EFI with distributor-less ignition, I can show a how to..

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Hmm..if that L24 has a lumpy cam, some good mods and ready for the track...for sure! ;)

 

Now that you've almost sold all the gear. Do you mind me asking why you decided to go back to the L-GATA ? :)

 

I must say when you did the RB25 swap I was contemplating the same thing, but now I'm not so sure.

 

 

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Well I thought the original matching numbers engine is lying under my work bench in a sorry state with the head off and covered in 1" of dirt. With the RB in the engine bay needing another 2-3000 dollars spent to make it come close to the L28 I had, I thought I would rather spend the cash on the original L24 and tweak it a bit and have it all mostly original than the RB in the zed with the power but the L24 still looking sad. If I had the funds, I would've kept both but beggars can't be choosers..I can always do it again, I know how but one thing I would do different, is buy a DET engine and install. Find an NA gearbox which I think will take the power of a standard 25DET and leave the engine standard. 160 odd kw in a zed is plenty for the track. In the HybridZ site, a guy has done a excellent write up on how to make your own sump out of ally. He makes it look too easy! and tempting!

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Welling having owned a 3.2L L28 stroker - I am sure I will miss the L-Gata engine with my RB conversion - never know one day just might have to purchase another zed so I can have both again.

 

So did you drive the RB before it was pulled out? What was it like? I assume you are keeping the EFI Hardware TB's and installing these on the L24 or are you going back to twin SU's?

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Mike, I drove it around for a while and liked it alot. The smoothness of the engine couldn't be compared to the L series. Theres a few youtube vids of it around Calder and Sandown. Those 120Kw's were fun but it really needs a good set of cams to really see the potential. That and adj cam gears would be perfect. The ITB's will be going back onto the L24 as is the Wolf V500 but with a L28ET distributor and coilpack and 3 ch. ignitor. One thing I thought of with the L series is what would it be like with a RB CAS mounted on the front driven by the cam? Instead of trying to find those turbo dizzy's which are hard enough, R32,33 CAS' are more plentiful.

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I did see someone had taken said R32/33 CAS and made a shaft and bracket so it could be installed were the dizzy goes :) so that is an idea given the dizzy is spinning at CAS speed :)

 

I will have to find those vid's, my RB has was you state, adjustable cam gears, larger cams, light RB26 ported head - fully balanced bottom end with polished rods etc. So I hope it goes well.

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Hi Dimitri

 

We seem to have mine just about sorted with the new computer.  We only went for multipont injection and batch fire ignition using the distributor as a trigger for now.  Just thought I'd let you know some problems we had that might help you decide what to use for a trigger.  With the Mitsubishi Electric distributor that was in the car (I think from a 280ZX?) the trigger signal was scattered about 5 degrees at higher revs due to play in the shaft.  To get it working we had to swap to a Hitachi distributor from an R30 (Thanks for the loan Bluerat) which are a much better distributor design with no shaft play and they give a better signal for the computer to read.  I should also not for people reading this that you have to weld the timing weights so they don't work for this setup.

 

I'm not sure on who makes the turbo dizzy but it looks more like the Mitsubishi Electric design and looks like it may also suffer from shaft play.  So I wouldn't trust the trigger signal this setup with the RB30 wheel would send to the computer.  In my opinion a CAS as you have mentioned would be a much better setup even if it is a bit harder to set up and not quite as neat.

 

Anyway, hope this info is helpful  :)

 

Cheers

 

Shane

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Shane, was the shaft play in the distributor body itself or the shaft/drive running from the oil pump to the dizzy? The L20ET dizzy I have has virtually no shaft play at all. Someone on the HybridZ site stated they connected a Oscilloscope to the L28ET distributor and found very little if any noise or "errors" even at high RPM. When I get to that stage, I will share the info I find out...Thanks for that info Shane...

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A bit of both but maily on the shaft.  We tried putting the plastic bush off the Hitachi shaft onto the Mitsubishi shaft which has a metal bush normally.  This made it a lot better but still not perfect.  Sounds like the turbo dizzy is a better design.  Good luck, I'll be interested to hear what you end up with so I can copy it later on  :P

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Hi Dimitri

 

Just thought you might be interested to know we ended up grafting a complete RB30 distributor into the L28 to fix the problems we were having with the new computer.  Long story but it turns out that wasn't the problem anyway!  I'm very happy with the end result though.  The timing stays perfect right through the rev range where we were getting a few degress of scatter with the L28 distributor.

 

Anyway, there's a lot of work required to make the RB30 dizzy fit but it can be done.  The L28ET dizzy with the RB30 wheel would be much easier and cheaper unless you're lucky enough to have a couple of very helpful mates that are fitter and turners  ;D

 

One thing you might find helpful is that we had to turn the wheel upside down.

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One thing you might find helpful is that we had to turn the wheel upside down.

 

is that because the rb30 dizzies spin in the opposite direction.

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is that because the rb30 dizzies spin in the opposite direction.

 

I'm not sure what way they spin in an RB30 but I'd say that must be the case.

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