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Topls82 · Joined: 08 Feb 2021 Posts: 89 Location: Chicago

Guys
I am sending my turbo for rebuild and modest improvements (not for race).
Majestic suggested I send along an upgraded billet compressor wheel
My blue plate has these numbers on my 1981 Turbo
K26 26604GA 4.10
5326 970 6022

What’s the recommended billet (KTS ?)
thanks for assistance
Frank

Cedric · Joined: 27 Aug 2004 Posts: 2742 Location: Sweden

Last time i checked the small 2660 wasnt available as a billet wheel, but that was a while ago. Have a scroll through the KTS catalogue to start with. Im not sure if there is enough meat to machine the housing for a larger trim wheel, that would give a noticeable stronger top end, even at standard euro boost.

My s2 931 put out 168hp at the hubs, just the larger 2664 compressor wheel and s1 wg spring 0.7bar as mods.
_________________
1980 924 Turbo
www.instagram.com/garagecedric/

Topls82 · Joined: 08 Feb 2021 Posts: 89 Location: Chicago

After reviewing some posts and available billet compressor wheels
Original wheel #5326 123 2007
Turbo part # 931 123 012.05
Marta 9 blade full flow K26K26-7007-54.5/64.4 ….suppose to be. Correct upgrade but not sure ..

So yours is a 2664 ? And is a direct fit ?
Also thought I saw some discussion for 2660 ?
Please enlighten me on the use of a Series 1 Wastegate spring vs 2
Some posts suggest an increase above .7 bar

Your setup and power would be quite acceptable

Thanks for assistance
Frank

Cedric · Joined: 27 Aug 2004 Posts: 2742 Location: Sweden

Topls82 · Joined: 08 Feb 2021 Posts: 89 Location: Chicago

Cedric
Thanks a lot for digging…!!
Seems this one will do the trick !

This research is not easy with lists of numbers that are endless..
Your setup is quite a mix of parts that integrate well for your needs

Much appreciate your efforts
Now onto my next challenge of vendor to rebuild my
AAV - Bosch 0 280 140 220

Quick overview of my engine is bought car with not running engine
It turns by hand …so I only want to rebuild just one time so am sourcing
All the parts for complete rebuild of all components …everything !

Great resource here on site with experts like you assisting
Regards
Frank

Cedric · Joined: 27 Aug 2004 Posts: 2742 Location: Sweden

Beartooth · Joined: 05 Apr 2022 Posts: 280 Location: Roberts, MT

My air admittance valve (we're talking about the idle compensator that allows more air when cold, then closes down as the engine warms up, right?) has always worked fine; only thing I've done to it is spray a little brake cleaner in and blow it out with compressed air. I think they're a pretty low-failure component, so maybe not worth monkeying with if you can find a used one.

On the bearings, I found a set on ebay, and that's might be the easiest way to find a set. The ones I got are pretty far undersized, so the crank will need machining when I use them. I suspect it'll be easier to find bigger undersizes because most people wouldn't put a motor back together without replacing the bearings, but not many would have the crank machined (even if it needed it). So the undersizes were more likely to sit on a shelf until a seller or wholesaler consolidated.

Anyway, like Cedric said, it's likely to take some shopping to do a rebuild, but it's possible and not drastically expensive if the pieces are all procured ahead of time. Only trouble is, given how rare some things are (like main bearings), that could mean starting sometime next month, or sometime next year...
_________________
1980 931 diamond in the rough

Topls82 · Joined: 08 Feb 2021 Posts: 89 Location: Chicago

Guys
Sent info to KTS to order and the K261 which is a 9 week lead time
However they suggested K267 available…the profile drawings looks slightly
Taller ?
anyone have experience with this model ?
Perhaps machine the housing ?
Thanks again for assistance

Cedric · Joined: 27 Aug 2004 Posts: 2742 Location: Sweden

The 267 is what they say is the "performance" design, its pretty much the type of wheel i have, with the taller wheel and extended tip design which kinda simulates a slightly larger wheel (by a little). No mods were needed on the housing.

I couldnt find the 267 anywhere in their online store, so I assumed they didnt sell those.

2670 vs 2670 billet, i wish he used a smaller hub nut, though it doesnt matter that much, very little of the compressor work is done at the center of the bladdes. The 2670 is pretty similar in blade design to your wheel, but it has a significantly larger inlet (70% of the diameter instead of 60% of the diameter).

_________________
1980 924 Turbo
www.instagram.com/garagecedric/

Topls82 · Joined: 08 Feb 2021 Posts: 89 Location: Chicago

Cedric
Great info again !
They sent me an up dated catalog but it was way to much info….
They said their site info is not upto date…
Glad to hear no mods …
Think I will go with it

Thanks
Again
Frank

Topls82 · Joined: 08 Feb 2021 Posts: 89 Location: Chicago

Cedric
Great info again !
They sent me an up dated catalog but it was way to much info….
They said their site info is not upto date…
Glad to hear no mods …
Think I will go with it

Thanks
Again
Frank

Mike9311 · Joined: 14 Dec 2004 Posts: 1793 Location: Chicago-ish

There is a 2660. I have to find the info (Volvo Penta and others)

Isn't this it?
https://www.ebay.com/itm/276131563017

I rebuilt the '82 k26 on my list with one similar. Can't remember but I might have had to machine down the nose tip in a lathe (-3mm or so) but otherwise no mods. I also think this was the 267 model you are referring to. Checking my pics about the machining part. Will post

This was in my notes
TRITDT Item No.
- 405-9901K-267
_________________
1980 931 since 1989
1981 Ideola 931 Club Sport
1982 931 Entwicklungsfahrzeug
1979 924 NA ohne 650 mit 471
1982 931 Red Resurrection - 951 IC
1982 931 parts car / resurrection?
1980 924 NA (R&D lightweight)
1982 931 wana-be GTR race car

Mike9311 · Joined: 14 Dec 2004 Posts: 1793 Location: Chicago-ish

I think its machined already in the pic. Sorry pics are big

Lock nut and red loctite. White mark on nut was from balancing

_________________
1980 931 since 1989
1981 Ideola 931 Club Sport
1982 931 Entwicklungsfahrzeug
1979 924 NA ohne 650 mit 471
1982 931 Red Resurrection - 951 IC
1982 931 parts car / resurrection?
1980 924 NA (R&D lightweight)
1982 931 wana-be GTR race car

Cedric · Joined: 27 Aug 2004 Posts: 2742 Location: Sweden

Not all K26 shafts have equal length, as ive also noticed that. Which i think might be the reason you had to take down the nose of the wheel.
_________________
1980 924 Turbo
www.instagram.com/garagecedric/

Mike9311 · Joined: 14 Dec 2004 Posts: 1793 Location: Chicago-ish

The new replacement shaft I used on the 2667 build was longer and would have worked just fine with this 2660 wheel. Plus it had a reverse thread so the nut can't come off.
_________________
1980 931 since 1989
1981 Ideola 931 Club Sport
1982 931 Entwicklungsfahrzeug
1979 924 NA ohne 650 mit 471
1982 931 Red Resurrection - 951 IC
1982 931 parts car / resurrection?
1980 924 NA (R&D lightweight)
1982 931 wana-be GTR race car