Rb25/30De With Rb26 Itb's Best Fab Method? Not A Conversion Plate

[sr20det510]

Hey Crew,

I have an RB25/30DE Setup in a C210 skyline.

I have just bought a full RB26 manifold and have a spare RB25 manifold ready to chop up.

I also have the RB26 flange plates that we will weld to the RB25 cut down manifold.

My main question is.

has anyone just cut the RB25 and RB26 manifold put them together and welded them shut or are the runners too ofset to do that?

Im trying to minimise the overall length of the set up for clearance issues to the brake booster.

Thanks in Advance

Not interested in a conversion plate so please dont suggest it as an option. not a fan of the injector position once its been moved 20mm away from the head.

[Bsa]

It may be possible to cut it off just after the injectors and weld a plate on otherwise Iv looked at doing this myself and a adaptor plate made properly will work just fine

[XRATED]

Weld up the unneeded stud holes, machine flat and re-tap new holes?

[r33_racer]

I can say with adapter plates and the greddy plenum on the 26 throttle bodies on a 25/30 will hit the clutch master cylinder and hit the lines exiting the brake master as well. So far 12mm packers under the sub frame has fixed the issue. However with a factory rb26 plenum it is fine with good clearance everywhere. In a r33 gtst engine bay. Possibly pointless info there, but in case any one wants to know. The adapter plates are 12mm thick each, so 24mm packed out from head.

[ISL33P]

Personally I would try and make the runners as long as possible for an NA car, especially when it has relatively small capacity....well compared to v8's, and lacks the bottom end torque to fill in the power curve down low.

Personally I would make a completely new flange/manifold to incorpoate the ITB's to suit the cylinder spacing.....it's not far off at all anyway. Is welding th ITB's to a flange an option?

Ariel

[MRHD66]

It has been done and I'm looking at doin this for my RB25/30 turbo