Jump to content
SAU Community

Recommended Posts

I've been looking at pics of R33 and R34 RB25 DET manifolds and I'm curious to know if the R34 GTt lower manifold can be substituted for the R33 one .

Main reason is to fit the GTts top feed fuel rail and retain all the R33s plenum (plumbing and IAC valve) .

If the gasket that fits between the upper and lower manifold halves is the same it may work .

Fingers crossed cheers Adrian .

That's only because the IACV is a different shape, which bolts on to the top half of the manifold anyway.

Disco I reckon that they would be the same, if not very very similar. Cannot say for sure if they would be interchangeable though.

I haven't fitted a Neo rail to a 33 so I don't know how far out the rail bolts are, but I think it would be fairly easy to fit, seeing the aftermarket rails have room. The lower spacers are only available in kits, but they are so easy to make on a lathe. The spacing for the rail bolts should be easy enough to fix. If a conversion kit was made it wouldn't cost too much in bulk...

The early WRX owners have similar issues converting from side feed to top, but a few companies have worked it out and now they sell similar conversion kits to what you RB guys need.

It really isn't hard to fit aftermarket rail as Arts did, and i did with 1000cc xspurts, just some stuffing around but very doable. Just paint it black for stealth look.

Not impossible to get the Neo rail on but probably more stuffing around than its worth .

If you look at the R33 RB25 lower manifold the side feed rail mounts at three points sort of below the rail . The GTt one mounts above the rail on the cast in water passage . The 33 manifold has similar mounting points for something else but they are closer together than the GTTs ones .

You could weld mounting pads to the lower manifold if it was off but most don't feel like removing it and it becomes a unique part .

If keen you could cut and weld different mounts on the GTT fuel rail but it's cad plated and could peel off inside and leave bare steel which isn't flash .

EFI Hardware advertises an adapter system that screws into the front of aftermarket rails to take the Nissan style rail mount reg so if it fits ARTs rail that makes life very easy . I think the rail has to have "machined O ring port" threaded sections back and front for this adapter to fit but I don't know enough about aftermarket rails to know if they are all like this .

I can lay my hands on a Nismo adjustable FPR and I'd like to know if their bypass port is any larger than the standard one .

A .

Edited by discopotato03

Yep. I saw that. I agree a black rail isn't too obvious and it's not that expensive, but the amount of those crappy fiveO injectors being sold shows how keen people are to keep the stock sidefeeds, no matter the consequences. I would love to be able to supply some easy way to swap over to top feeds for those guys that want a stealth upgrade. I like stealth options.

Yep I tend to think an aluminium rail in natural finish or matt/flat black would be alright provided the fittings aren't some silly nail polish colour .

It seems the -8AN (3/4 x16) parallel thread is a defacto standard and seals with an O ring on a bevel in the ends of most aftermarket rails .

I reckon if the EFI Hardware adapter parked a standard or equivalent reg on the front of a plain rail it shouldn't attract too much attention and at least put the return line where it's supposed to be .

A .

So have you given up with the Neo rail Disco? Send it down so I can do a fit up on a 33, I might be able to work something out, anyone in Melbourne got a spare lower plenum?

Why not just put top feed rail and short injectors in your r33 intake? Just have to llose

... that's what I'm running in my drift pig? r33rb25det, aeroflow rail, ev14 1000's.

J.

He wants the stock look as much as possible, stock reg at the least.

The Aeroflow rails are set up for mid (3/4) length injectors, using the short ones requires shortening the spacers which scares some people.

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

    • I'm looking for some real world experiences/feed back from anyone who has personally ran a EFR7670 with a 1.05 exhaust housing or a .83 I'm leaning towards the .83 because its a street car used mostly for spirited driving in the canyons roads. I"m not looking for big numbers on paper. I want a responsive powerband that will be very linear to 8000 rpm. I dont mind if power remains somewhat flat but dont want power to drop off on top. The turbo I've purchased is a 1.05, although the mounting flange T3 vs T4 and internal vs external waste gates are different on both housings, I not concern about swapping parts or making fabrication mods to get what I want. Based on some of the research I've done with chat gpt, the 1.05 housing seems to be the way to go with slightly more lag and future proofing for more mods but recommends .83 for best response/street car setup. AI doesn't have the same emotions as real people driving a GTR so I think you guys will be able to give me better feed back 😀   
    • Surely somebody has one in VIC. Have you asked at any shops?  Is this the yearly inspection or did you get a canary?
    • This is where I share pain with you, @Duncan. The move to change so many cooling system pieces to plastic is a killer! Plastic end tanks and a few plastic hose flanges on my car's fail after so little time.  Curious about the need for a bigger rad, is that just for long sessions in the summer or because the car generally needs more cooling?
    • So, that is it! It is a pretty expensive process with the ATF costing 50-100 per 5 litres, and a mechanic will probably charge plenty because they don't want to do it. Still, considering how dirty my fluid was at 120,000klm I think it would be worth doing more like every 80,000 to keep the trans happy, they are very expensive to replace. The job is not that hard if you have the specialist tools so you can save a bit of money and do it yourself!
    • OK, onto filling. So I don't really have any pics, but will describe the process as best I can. The USDM workshop manual also covers it from TM-285 onwards. First, make sure the drain plug (17mm) is snug. Not too tight yet because it is coming off again. Note it does have a copper washer that you could replace or anneal (heat up with a blow torch) to seal nicely. Remove the fill plug, which has an inhex (I think it was 6mm but didn't check). Then, screw in the fill fitting, making sure it has a suitable o-ring (mine came without but I think it is meant to be supplied). It is important that you only screw it in hand tight. I didn't get a good pic of it, but the fill plug leads to a tube about 70mm long inside the transmission. This sets the factory level for fluid in the trans (above the join line for the pan!) and will take about 3l to fill. You then need to connect your fluid pump to the fitting via a hose, and pump in whatever amount of fluid you removed (maybe 3 litres, in my case 7 litres). If you put in more than 3l, it will spill out when you remove the fitting, so do quickly and with a drain pan underneath. Once you have pumped in the required amount of clean ATF, you start the engine and run it for 3 minutes to let the fluid circulate. Don't run it longer and if possible check the fluid temp is under 40oC (Ecutek shows Auto Trans Fluid temp now, or you could use an infrared temp gun on the bottom of the pan). The manual stresses the bit about fluid temperature because it expands when hot an might result in an underfil. So from here, the factory manual says to do the "spill and fill" again, and I did. That is, put an oil pan under the drain plug and undo it with a 17mm spanner, then watch your expensive fluid fall back out again, you should get about 3 litres.  Then, put the drain plug back in, pump 3 litres back in through the fill plug with the fitting and pump, disconnect the fill fitting and replace the fill plug, start the car and run for another 3 minutes (making sure the temp is still under 40oC). The manual then asks for a 3rd "spill and fill" just like above. I also did that and so had put 13l in by now.  This time they want you to keep the engine running and run the transmission through R and D (I hope the wheels are still off the ground!) for a while, and allow the trans temp to get to 40oC, then engine off. Finally, back under the car and undo the fill plug to let the overfill drain out; it will stop running when fluid is at the top of the levelling tube. According to the factory, that is job done! Post that, I reconnected the fill fitting and pumped in an extra 0.5l. AMS says 1.5l overfill is safe, but I started with less to see how it goes, I will add another 1.0 litres later if I'm still not happy with the hot shifts.
×
×
  • Create New...