I am doing the NA to Turbo brake conversion on my early offset car. I was hoping to just buy a set of new turbo struts and install them however I have not found many/anyone making complete struts.

Is there something missing here or do I need to find a set of 86 used turbo strut bodies and throw in new cartridges?

Anyone have a pair they want to part with if thats the only option?

 

Looks like I found a pair of used struts. Hopefully they come in rebuild able shape and all parts just swap over.

 

You need 86 Turbo struts, ftw buy a set of used ones and send them to Paragon who will fit Koni insets into them.

Better still, convert to late offset at the front wyit as the brakes on the 87+ cars are better facilitated, the hubs are stronger and the bearings beefier. You’re going to need new wheels anyway and you can readily buy new later struts from a number of places.

 

You can send your koni struts to koni and have them rebuild. The down time is over a month though. Well worth it. I'm not a fan of the cartridges.

 

Op has early Boge/Sachs struts, they come from the factory with cartridges and can be changed easily without sending them anywhere. However his problem is that he cannot use them with 944 Turbo spindles which are needed for the Brembo brakes.

 

Thanks for clarifying. My suggestion still pertains. The 86 turbo Sachs struts will need the housings to be cut if one wants to rebuild used ones. I suggested purchasing used koni struts and having koni rebuild them instead of using cartridges.

 

Curious why you dislike the cartridges? Koni made them specifically for the late struts and cutting the housings just makes them open-ended like the early Porsche struts. Only difference is they attach through the base.

Also, are you sure Koni still offers the rebuild service, Ive heard they stopped but maybe I’m mistaken.

 

Koni still rebuilds them. I'm going to send out a set for rebuild, that I purchased from a fellow lister recently. The cartridges are ok if you have sachs struts.

They eventually will fill with water and in freezing weather can bulge and rust internally. They also don't dampen as well. The stock koni piston is much larger and I assume the passages are larger along with a larger oil reservoir.

There are many people that experience the bolt shear as well on cartridges. Also , speaking with koni, its best to use a koni strut even with cartridges because, one can thread the collar over cartridges for a better seal from the elements.

All of these reasons were discussed with a koni engineer recently.

 

Thats all good info, thanks for sharing.

 

Thanks all. Just some additional info. It is an early offset late car. 85.5. Car already has refinished early offset 16” phone dials.

I am swapping the spindles, hubs, rotors, calipers (using S2 units for the later seal design), adding the bias valve, etc etc.

I was hoping to just buy new complete struts but realized this was not an option. I got a pair of used 86 turbo units coming and will either swap over my boge inserts or use koni.

Which bias valve version are folks using? 18/5? 33/5?

 

I have the inserts on my 968 and like them.

Here is some imore nfo from Koni for our knowledge base.The insert and the old full body strut use the same exact piston, both 33mm. The could be a few benefits from the full body strut If the car is being used strictly as a dedicated track car and smashing/jumping rumble strips in that they constructed of less components (strut vs. strut body/insert). It does hold more oil as the reservoir tube is larger, compared to the insert design. But for normal street driving or the occasional track day or autocross, I would have zero worries using the insert for the sealed strut tubes.

We do not rebuild shocks in house any longer and have not since 2016. I personally use to run the rebuild center myself from 2012-2016, prior to that space being absorbed into the expansion of our Railway shock production cell. So no we do not rebuild here at KONI any longer. There are 3 privately owned businesses however that are Authorized Rebuild/Service centers, that can still provide that service to KONI user. We just no longer do it here.

As for the bottom bolt, again, that same exact design has been used since the 80’s, and is currently used for several different application Honda, Subaru, Saab, Porsche, Toyota, etc.… If someone has an issue with the bolt shearing off they are doing something incorrectly..

 

Thanks for the info Charlie. What about using the non Koni housings such as the Sachs with the Koni cartridges. Do you recommend using them or sticking with the Koni housings?

 

I used the Sachs and think they are great. Talk with Jason at Paaragon and he can give you good advice.

 

Why to you want to switch from NA to turbo brake calipers?
The NA brake calipers provide more than needed braking capacity.
My 1983 944 NA race car with OEM brake calipers provides 0.6 g braking with race tires, and applying threshold braking pressure which could add another 15 to 25 % more g deacceleration.

Save the money and spend it on other upgrades such as NA tune from Lindsey Racing that adds up to 15% more HP for about $700. Call Mike at Lindsey Racing

 

What about water? Are they up to the task if the seal is compromised?