im4duke

I bought a HF-S from IA several weeks back. Am finally getting around to installing it and am replacing hoses where I can.

My original Ruf turbo had a straight 2.75 ID hose from the end of the intake neck to the compressor inlet. The HF-S has a dimension of 3.125 OD on the compressor inlet.

I looked at www.hosetechniques.com and cannot find exactly what I need. The following transitions are available:
A - 2.50 -> 3.25 x 3L
B - 2.75 -> 3.00 x 3L
C - 2.75 -> 3.50 x 3L

The original piece of hose was 2.25 long, but I think I can get by with a standard 3 inch transition and maybe carefully trim it to its minimum length.

The real issue is what diameters to go with. The intake neck has a raised ring/lip at the end and it seems like I might be able to force a 2.50 on it. That would allow me to use a 3.25 on the turbo. Although, I have no idea how flexible these hoses are and whether I would be better off forcing a tight fit or clamping down on a larger hose. I am leaning toward A or B.

Anyone else run into this same issue? Any other sources for silicon hose that carry lots of sizes? Is there a "shim" approach that can be used on the turbo to permit use of a larger hose? I'm open to anything...

Stephen, Kevin?

Thanks for any help!

Cheers,
Maxx

Sameer

Maxx,
Curious, which Ruf turbo did you have? The K29?

PorschePhD

Max,
If your hose is in good shape it will stretch around the neck. If not and it is hard call me and I will send out some hose for you. It will set you right up and get that on!!

im4duke

Sameer, I'm not exactly sure what turbo it is. I'll take a pic or two tonite and post to see if it can be ID'd.

Stephen, thanks, I'll call.

Sameer

Maxx,
that would be great and perhaps Stephen could help identify it.

im4duke

I have a temporary fix to my hose issue.

Recall, my new HFS has a 3.125 OD compressor inlet vs. the 2.75 OD on my former unit. The metal intake pipe leading to the turbo has 2.75 OD. I couldn't find a short transition in these sizes.

IA sent me a piece of 2.75 ID and a piece of 3.00 ID. Definitely could not stretch the 2.75 over the turbo nor could I clamp the 3.00 enough to feel good about it on the intake pipe.

Turns out, the 2.75 fit nicely inside the 3.00. Thus, I am doubled walled on the intake pipe.

It's only intended to be a temporary solution. Fortunately, the pressure on the intake should be relatively low. Anyone see a major risk here?

The only alternatives I can think of are trying some 2.75 ID silicon hose that might stretch more easily, or enlarging the end of the intake pipe.

Anyone have any other suggestions?

slownrusty

Maxx - I have done that same hose inside hose technique on my last turbo car and had no problems whatsoever - this would be fine for even a permanent solution. I always use T-Bar clamps to ensure everything is snug and the T-Bar clamps have nylock in the nuts too, so they will never back out.

This is the car I did the hose inside hose technique....274wheel hp all from 1.6L and weighed 2200lbs.



Hope that helps.

Yasin

Kevin

Have you tried warming up the hose in an oven to 200 degrees? Once pliable it will be easier to slip on..

im4duke

Thanks guys.

Kevin, I hadn't thought about heating it up, although that sounds like a great idea. However, since I already have it on with the doubled-up hose I guess I'll go with that unless someone convinces me that it's a bad idea.

Yasin, glad to hear that it's not uncommon. Sure beats having something custom made...BTW, that engine looks awesome. Love the excessive use of aeroquip. I have several t-bolt clamps that I was going to use. Unfortunately the largest ones I was able to source locally were a fraction too small. Will order some later and replace them. The clamping strength of the inline screw type just isn't there.

nathanUK '81 930 G50

Becareful not too overtighten and distort the metal tube/turbo housing. I don't think they are very thick walls.

Kevin

Nathan you won't hurt or distort the hose ends of either end of the turbocharger with a hose clamp. The clamp will break before you crush the ends.

Im4duke I would suggest that you do try to install the 2.75 hose and use some heat if need be.. It requires some wrestling, but it will work..

nathanUK '81 930 G50

That's good news.
What about the elbow pipe coming into the inlet ? That doesn't look very thick.

Not trying to hijack the thread but I would like some advice about the restrictor for the oil line that feeds the turbo.
That ball and spring sits inside a bush ontop of the engine and then the banjo bolt goes into this ? Does the spring go in this bush first and then the ball after ? I take it the ball hits the Vee cut into the banjo bolt as the spring pushes it there ?

Thanks In Advance Kevin. Sorry Maxx.

Kevin

Nathan, you aren't going to break it unless you drop it. There isn't a spring in the banjo-9mm check ball assy. What advice do you need?

nathanUK '81 930 G50

So just a ball sits in that bush that the banjo nut screws into?
I can feel it with my little finger.

SGOGT4

I just installed the HFS on my 930 and my mechanic warmed up the original hose in hot water until it was pliable enough to stretch over the 3" opening.