Bringing the 944 turbo into the 21st century

[chris white]

Anybody else old enough to remember when Cometic came out with the gasket with separate high end 'F1' style rings that were vented to the cylinder to increase the ring pressure as the combustion chamber pressure went up? That was 15+ years ago....very similar to the SCE idea. did not work so well on our cars and they were stupid expensive.
If anybody tries to sell you on a headgasket by telling you a key feature is that you don't have to machine the head / block then just walk away.....fast!

[Cyberpunky]

Headgasket failure is 80% caused by tuning issues. If your tuning is off nothing will help you keep it all together. good building and truing practice has worked for decades. There also has been a steady advance in the quality of all good parts. Some folks seem to be better at selling their 'miracle' parts as completely revolutionary stuff....
the engine I just finished up is using an off the shelf GT35 turbo (not even a gen2!) and i'm making 450/450 to the wheels at a track usable boost and over 400ft lbs before 3500 rpm - its designed to run for years. its using a cometic gasket on Darton sleeves....both been available for 20 years. If you know how to build them they work.

no doubt but sadly many vendors are still selling old laggy turbo's at top dollar when massive improvements have been made in that area. No ones talking miracle products here but if a better HG is available for our engines why wouldn't we use it? My cars been going great since new, so clearly porsche "knew how to build them" back then too. That is not the point of this post, and it is certainly isn't directed at people like you making solid engines but generally speaking there hasn't been any modern tech thrown at these cars, by any vendors, for years. Sure wizards like you can do magic with these engines, but you are not selling products as a vendor for all and are only able to help your customers to take advantage of your skills and service

[chris white]

I should say that I may be jaded from being around 944s for so long. Too many times I have seen new vendors come up with ‘the next big thing’. In reality we are in the era of small incremental improvements. To be a real believer in the benefit of a new product I would have to used it for a couple of hard track seasons.
I also have a bad reaction to over hype. I have never used an ultraspool, I have no doubt that it’s better than 1980’s technology. I have a hard time believing that it miles ahead of a correctly sized garret gtx with Tial hot side.
Similar thoughts on head gaskets - properly built and tuned engines don’t have head gasket issues….because it’s the prep, building and tuning that matter. Marketing a new type of head gasket as a cure worries me. How many are out there with 10k miles of use with lots of track days? My experience with working with Darton on the MID sleeves taught me that there is always a learning curve and you can’t replace skilled machining and assembly. I have not had any issues with the MIDs but many that installed their own have.

So….when ever I hear about ‘new technology for 944s’ I am a little skeptical in the beginning - especially if it claims to make huge improvements over other available parts.

[Darwin]

I may be a little biased, but my Darton sleeved MLS sealed engine has been great up to about 20psi. I am looking at changing the turbo, but beyond that I’ve had zero issues. Chris did build it, though, so I capitalized on his experience with the components selected. I, too, have heard about the issues with sleeves and the cometic gaskets by others. I would assume experience/procedures played into failures more than component design/quality.

[chris white]

I may be a little biased, but my Darton sleeved MLS sealed engine has been great up to about 20psi. I am looking at changing the turbo, but beyond that I’ve had zero issues. Chris did build it, though, so I capitalized on his experience with the components selected. I, too, have heard about the issues with sleeves and the cometic gaskets by others. I would assume experience/procedures played into failures more than component design/quality.

Geez Darwin, your engine is over 10 years old….it’s just getting broken in!!

[Darwin]

I may be a little biased, but my Darton sleeved MLS sealed engine has been great up to about 20psi. I am looking at changing the turbo, but beyond that I’ve had zero issues. Chris did build it, though, so I capitalized on his experience with the components selected. I, too, have heard about the issues with sleeves and the cometic gaskets by others. I would assume experience/procedures played into failures more than component design/quality.

Geez Darwin, your engine is over 10 years old….it’s just getting broken in!!

You can attest to those 20psi runs!

[Cyberpunky]

I should say that I may be jaded from being around 944s for so long. Too many times I have seen new vendors come up with ‘the next big thing’. In reality we are in the era of small incremental improvements. To be a real believer in the benefit of a new product I would have to used it for a couple of hard track seasons.
I also have a bad reaction to over hype. I have never used an ultraspool, I have no doubt that it’s better than 1980’s technology. I have a hard time believing that it miles ahead of a correctly sized garret gtx with Tial hot side.
Similar thoughts on head gaskets - properly built and tuned engines don’t have head gasket issues….because it’s the prep, building and tuning that matter. Marketing a new type of head gasket as a cure worries me. How many are out there with 10k miles of use with lots of track days? My experience with working with Darton on the MID sleeves taught me that there is always a learning curve and you can’t replace skilled machining and assembly. I have not had any issues with the MIDs but many that installed their own have.

So….when ever I hear about ‘new technology for 944s’ I am a little skeptical in the beginning - especially if it claims to make huge improvements over other available parts.

Well these new generation turbo's specifically designed for our cars have been getting impressive results by spooling quicker and lower and being able to produce large horsepower. A lot of attention to detail has gone into them. Basically built for customers needs and virtually blueprinted in execution. It's not that others couldn't have done similar, just that no one had bothered and if you know the vendors out there, you also know the only options for most(till now) are 90s era and laggy, as you would expect.

The HG are not new but are for our engines. The technology has trickled down from high performance uses like drag racing and time attack etc. I am not sure who got the ball rolling whether it was Gustaf or Joshua from Valley cylinder heads but one of the guys on premier group followed through and got a large batch made. Hopefully they will go into normal production now but I grabbed a spare just in case its needed some time down the track

[Tom]

My Vitesse turbo makes 15psi at 3k rpm and over 500/500 at the wheels on my 3 liter -- so not really a turbo I'd consider laggy, unless you compare it to a modern turbo car like my 992TTS that has virtually no detectable boost onset. And that was my 'old' VR stage 5. The newer one I have now seems even peppier. And I have a newer one still waiting for the next motor. Based on results, it feels like Johns' been keeping up with the technology.... I have not personally tried the voodoo stuff so can't really comment, since I tend to gravitate toward the tried and true and am a professional cynic when it comes to marketing claims. I'm sure modifying the mount opens up a ton of possibilities though. Options are good (especially for cars this old) and if you and others are swearing by those turbos after installing and using them, then amen!

I'm still mulling which HG to use.... How much real-world experience in a 951 is there with the vulcan? Would love to hear from track guys that have beat on it hard. I tried to get feedback from Gustav, but didn't hear much.....?

And, more importantly, it's nice to see you back Bruce. Hopefully, talking cars and debating turbo merits can offer a tiny bit of happy distraction and comfort as we navigate life.

[Thom]

A turbo is only just about flowing a certain amount of air under different boost levels at some rotating speeds. It doesn't matter where the turbo comes from, but it for sure always feels good to be seduced by supposedly new products as playing lego with cars is a big part of the fun with these cars.

[chris white]

I still remember a vendor (now long gone) that used to tell people his impellers were custom made in Australia and worked better because they were from the Southern Hemisphere!
I didn’t know the the coriolis effect worked on Turbos!
There are some maching ‘blueprinting’ things that can be done to make a particular turbo be as effective as possible - Charlie at evergreen, Tim at Tim’s turbos and John at Vitesse (I am sure there are others). There are tons of options for basic configurations that you can get from oem manufacturers and billet impellers from other (I liked a lot of Tial parts and now they have spun off Xona rotor)…..so there are tons of choices for your 944. If anybody is trying to sell you that there is a new miracle solution they may have a good product….but it not a miracle and I’ll bet I can match it or out perform it with a carefully chosen ‘off the shelf’ turbo