Jump to content
SAU Community

Recommended Posts

Hey Guys,

Been offered an engine out of a very late series 1 stagea to go into my r33. The guy I'm buying it off hasn't opened it up but is determined that its a neo inside. It has a neo crank sensor (plastic cover) but the r33 coils will bolt up to it and not the neo coils. Now looking at the tomei website as I was going to put tomei cams in it, There is a different cam for 25's between 9/97 - 8/98. Looking on FAST at work all the parts (head, lifters etc) are the same number as all the R33 parts. The only thing in common with a R34 is the CAS. Talking to a reputable engine builder that builds race 25's, he has told me that if it has a plastic cover CAS it MUST be a neo. Has anyone come across this late S1 stagea or very late R33 type engine before and if so what internals has it got? As far as I can tell its a noraml 25 with a neo type CAS? Any help much appreciated.

Is the engine local to you? Might want to get someone with rb25det neo/standard experience to pop down there with you and check it out...

Are there other visual differences other than the plastic covers? Maybe get the seller to take a bunch of pics of it for you and post them up here?

As far as I can tell its a noraml 25 with a neo type CAS? Any help much appreciated.

Yep, thats what it is. In 1997-98 and immediately prior to the R34 there were a few R33's made that had a few different things about them. The 40th Anniversary model was one of them. You could say they are a series 2.5, but they are not recognised as such. There is a thread some where on here with differences between models, not sure if the '98 is covered though. They are not a Neo.

If you get Tomei cams then order for the '98 R33, otherwise the CAS key will be wrong.

Yep, thats what it is. In 1997-98 and immediately prior to the R34 there were a few R33's made that had a few different things about them. The 40th Anniversary model was one of them. You could they are a series 2.5, but their not recognised as such. There is a thread some where on here with differences between models, not sure if the '98 is covered though. They are not a Neo.

If you get Tomei cams then order for the '98 R33, otherwise the CAS key will be wrong.

Thats exactly what I thought. Cheers for the replys guys.

Question: is the inlet manifold of late series 2 like a neo or like a 33 manifold?

The answer to this could help OP and further my knowledge aha.

Well, they're not Neo's, so they don't have any of the things that were actually different different (ie that actually matter). That's the head, the inlet manifold......

R33 intake manifold will bolt onto a neo head so it is a possibility that they made them with 33 intakes.

Actually, there might be something in that. I was looking to buy a Neo a while back and I think it was at Adelaide Jap that there was an engine that they claimed was a Neo - but it didn't have the R34 inlet manifold. Engine was from a C34 Laurel. Had Neo CAS, Neo type ECU.....but looked like an old 25. But here's the kicker - the guys there said that they'd pulled the top off it and swore that it had solid lifters, just like any Neo.

So, I wonder if there is not a vague halfway motor hiding in Nissan's closet that needs investigating.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • You will need to extend the turbo inlet pipe somehow, which could/might be done with silicone/rubber pipe, but might need steelwork, depending on your intake. And you will need to change the pipework on the outlet in teh same way, but this is more likely to need steelwork.
    • I see... Any idea how much fab work is required? I note the Hygear megathread but its like 900 pages
    • I should try the experiment you're talking about, the throttle switch is still there carried over from the R32 and it's still all wired up but after I did the whole intake manifold refurb and had to recalibrate the TPS I managed to somehow get the idle switch reporting activation at 0.22V, then when I adjusted it to 0.45V for idle it decided the engine was permanently no longer idling which caused some very weird behavior, closed loop idle was disabled so it would basically be at the whims of the cold start valve and whatever the base timing table was at. Then just unplugging/replugging the TPS with the ECU live caused it to relearn the idle TPS position and decide 0.45V was idle. Presumably there's nothing in the TPS that allows for the throttle switch to "recalibrate" like that, not easily at least.
    • Duh... to answer my own silly question, it's actually described in the FSM... ...400 pages away at the end of the manual, for RB25DE/DET signal descriptions, it cites the TPSwitch signal action, is dependent on the TPSensor value ~ this tends to infer the builtin POT voltage signal is the primary, and the switches are fallback/secondary should the POT fail/TPSensor signal lost (and switch alone with no TPSensor signal allows for base idle speed setting).... makes sense... they (TPS units) used to fail/wear the POT with time, they're not exactly built to last ~ having the switch as a redundancy gets around this...(or, it's less likely both signals would be lost as they're on different power rails)... and of course wrt RB26DETT, you have to electrically disconnect the IACV solenoid from the harness, to defeat idle air control...  
    • Dose is unaware just how much fun 145-150kw would be in a 2.5L NC MX5. It would be one of the most fun things to drive to ever grace SAU.
×
×
  • Create New...