IHI RHF4

[MY95]

Now we know these are the third turbo found on the 2.0 HDI 90's,
What are these like to drive compared to the GT15/K03?
Worth an upgrade for stage 1 or 2? 
Do they bolt straight on?
Can this turbo be pushed a bit more than a GT15/K03?
There isnt much info on these online so wondered if anyone had any information.
Cheers

[bashbarnard]

I had a look into this not to long back. It bolts up with the manifold from the car it was off. No idea about clearance issues or exhaust. It SHOULD be better for a stage 2 map and slightly more reliable however no one has proven this yet. So crack on I say and help the community with information

[toseland]

i wonder if thie RHF 4 manifold would be able to bolt onto the RHF5....

[bashbarnard]

i wonder if thie RHF 4 manifold would be able to bolt onto the RHF5....

It does not its the wrong way round.

[Jonny81191]

I'd say go for something bigger if you want to make over 150 BHP. A GT20 or an RHF5 would be much better for stage 2 power, and anything less than that you'll be fine with the stock K03 or GT15.

Obviously the RHF4 could be made to fit and easily so, but there really is no point. IMHO anyway.

If you want a good fast spooling stage 1+ blower, I'd say a VNT (GT17 or 20) would be the way to go for near (or even better than) stock driveability.

[Poodle]

As above tbh, not worth it imo considering you'll get 90% there with a stage 2.

[MY95]

If only a GT17/20 setup was cheaper Jonny!

[Poodle]

Tuning doesn't come cheaper than a 306 lol.

[Jonny81191]

Yeah, you can buy a GT1749v for less than £50 or a GT2052v for less than £100. Anything you fit will need adapter plates anyway, and the only difference for a simple VNT setup is in the mapping (which you're doing anyway) and a boost can which is cheap to set up.

[MY95]

The parts arent that expensive, its the labour cost thats the killer (I wish I had the mechanical skills/knowledge of yourselves Poodle and Jonny!)

[bashbarnard]

You think johnny or poodle had the mechanical skills at some point. They went out and learnt. Always a chance to start learning.

[MY95]

Id love to learn how to do all the things most people on the forum can do, the question is where/how, I can do brakes, servicing and body parts and that's it so far

[bashbarnard]

Where on your driveway how use the forum to ask. Its possible. Id never even heard of box mounting turbos untill a few years back. Still went ahead and done it. Lol. Haynes manual is your friend if you are unsure.

[toseland]

be careful with some of the torque values in the haynes book of lies.. always double check with manufacturers spec for the actual figures just in case as there have been known to be inaccuracies (some detailed above in the stickies here) for some vehicles..

the how to's are generally good however.

[Poodle]

Haynes manuals take a lot of stick from professionals, but for the enthusiast learning the ropes you really can't beat them. Bear in mind i only picked up a spanner for the first time about 6 years ago...

[bashbarnard]

They take stick from professionals for a reason BUT exactly what poodle said a good base to start learning

[toseland]

Haynes manuals take a lot of stick from professionals, but for the enthusiast learning the ropes you really can't beat them. Bear in mind i only picked up a spanner for the first time about 6 years ago...

that explains a lot =D

[Poodle]