Campeck

the exhaust side?
I saw a guy who had a k&n filter on his car that took away aaaallll the spce that the filter took up.
couldnt tou do that for space and horspower and not risk the turbo(maybe) heating up to much and all the pipes that go to the turbo melting

'88-924S

Don't forget the bastard children out there in 924S'. I'd LOVE to t-charge my '88 924S, get the Carrera GT body kit and freshen up the interior with new carpet/seats. This kit would work for those of us who want to build their 'dream car' from relative scratch too.
Sounds great to me as long as it was ch$$p enough. Maybe $2500 - $4000??
Anyway, as long as it's reliable, like bulletproof as the rest of the engine than I believe you'd sell quite a few of these kits.
Keep us posted on this please.

Crippler

Well for exhuast I am running a 2.5 inch system, with no cat and a straight through muffler. However this doesn't seem to be cutting it and I will be putting a 3inch system on.

For fuel I am using a MF2 mirco fueler. With two injectors in the intake rather than just the one that Callaway used. I have more than enough fuel with this set up, actually too much. I need to do more tuning and get it get cut back some. However in the mean time I rather have it rich to be on the safe side of things

88BlueTSiQuest

A high compression engine running lower boost numbers should actually be more of a potent combination than a low compression engine running at higher boost.

The high compression would give you more lowend torque, and should start spooling the turbo faster. Low compression would require the turbo to spool before it builds any real torque numbers.


Great reading, found here.

kennycoulter

how much are the powerhaus pistons? if youd go that route i think theyre 8:1 ratio instead of 7:1 for stock? not too sure. you know if you go that route

John..

I disagree on the compression ratio quote. The main reason people can run more boost today on top of higher compression is the advancements in compressor and intercooler design (i.e. more efficient), as well as the myriad of electronics available to retard timing and do fuel mapping. If you can keep the heat out of the combustion chamber, you are in tall cotton. That article was clearly written around a supercharger, not a turbo, and it was probably a centrifugal supercharger that makes high boost at the very end of the RPM scale only. The turbo has no issue with dialing in the boost as you like it, assuming it is sized correctly.

You don't See Porsches running around with factory motors boosting over about 9.5:1 or so on the compression. People have done low boost on 10:1 compression, but there is more potential of detonation. Yes, you can boost a 10:1 motor, but don't expect it to last and get ready to start replacing head gaskets and attempting to beef up that joint to sustain some detonation, or lower the boost. I'd prefer to do it like the factory does and start with an 8:1 or 8.5:1 motor that can withstand 14 or more lbs.

It also has a lot to do with basic designs of the combustion chambers on the car. Personally, I would not feel comfortable throwing a lot of boost on top of a 10:1 motor and why run just 4 or so lbs, it is not cost effective at that point. To make it worth while, I would say the 944 would need at least 9-10 lbs and that would be a nice safe level for a reliable conversion. Perhaps the 9+:1 motors could be boosted and still have longevity, but I will reserve comment on that until some numbers are around to prove it.

There is no problem with putting the turbo on the exhaust side of the engine. That is where they reside on almost every turbocharged car out there today. My 93 S4 had 175,000 on the clock with the stock turbo resiging just inches off the manifold.....then I upgraded it to get more power. The 911 TTs turbos ride down there near the exhaust side as well.

There are 100 ways to skin this cat, some probably better than others...

Sgopher

I would be interested. Depending on price and when it becomes available. I live in Columbus, so I would definitly be able to come down to Cinci and see it in action. Sounds like a fun project.

ljd-924SE

by the time something like this would be fully developed, i'll probably be in positions to purchase the kit and this sounds ideal for me. i do have to keep my A/C though (florida resident) and i'd prefer to keep much of the low end and just keep the boost low. i think between $3-4000 would cover a quality kit. i'd hate to go any cheaper and end up sacrificing quality and durability.

88BlueTSiQuest

I really don't see any reason a supercharger shouldn't fall under the same rules as a turbocharger. Aside from the fact the turbocharger can reach full boost at a much lower rpm range than a supercharger, as the supercharger is belt driven and it's boost level is set by the pulley size to engine rpm ratio. They do still achieve the exact same goal, raise the effective compression of the motor, thus increasing horsepower.

The way I see it, if all things were equal in a perfect world. An engine with 9:1 compression vs. the exact same engine with it's only difference being a higher 10:1 compression, would have the same overall outcome on the top end with boost. The higher compression engine wouldn't see the same boost levels as the lower one, but the overall effective compression ratio would be the same with both motors at full boost. So, in my eyes, the higher compression engine should of been able to spool the turbo a few hundred rpms quicker than the lower compression engine, and would of also had a few more lb.ft. of torque available to it at the start.

They may end up dyno'ing at the same overall horsepower, but the torque curves would be entirely different, in favour of the higher compression motor. And that higher compression motor would also lay down some nicer performance numbers due to the added low end torque. IMO.

The key to it, would be in being able to control your own fastination with the boost control ****. Either way you slice it, too much boost can equal melted pistons.

pete944

John, I saw your 928 at the VW/Porsche show last summer and I was very impressed. It's a nice piece of work.

X 944 X

under 3k would have me interested... id have to have a minimum 50hp gain to make it worth my money. I guess we would be shipping the 944's down to you huh? If you can put me in the LOW 200 range, id be in for the conversion. I couldnt see spending more than 3k in an upgrade like that, because for 2k more or so, id have ANOTHER 944s or maybe a turbo for 1k more or so...

kennycoulter

yeah ill ride down with that gopher guy. my svo and many of the svo owners i talk to are running around 18 psi of boost. i know its an iron block, but the rest of the equation is similar. forged pistons, redline around 7000 to 7500, overhead cam, 2 valves per cylinder, roughly the same compression ratio. so..........why cant these cars handle as much boost? is it the "aluminum" block? all of these people usually get around the same miles out of their engines. and yes new turbos usually only go for 900 for a garret. so i dont see how it couldnt be done for 3000or so. for the 5.0 there are kits used for the stock bottom end thatll get you 525 at the wheels for 5,000. and thats 2 turbos and an entire kit. boost around 12 psi. just giving my ideas. im kinda poor. so im trying to bring down the price.

Gerry

I would like to turbo my 16-valver 944S. What do you guys know about doing one of these conversions?

kennycoulter

more updates please....................

John..

Thanks Pete, I was still in development at that point with the MAF and new intercooler, but she is all ironed out now and will put down about 370 to the rear wheels and over 380 ft-lbs to the rear wheels. The MAF converter was custom made for my application and the intercooler is of my design to fit Callaway's intake piping.

It is this kind of vision I can see working for the 944, but guys here is the catch....there are several iterations of the Motronic over the years. I have done some preliminary investigation into what it would take to do a conversion. Ultimately, the most cost effective way to do this correctly will be to intercept the trigger off of the flywheel and then an MAF input and then alter/ delay these signals to send them back to a stock ECU to get the fuel and ignition correct.

I am still not totally comfortable with throwing the boost on top of the 9+:1 engine, especially with the cast internals, but it may be possible with the lower boost levels. It is all about longevity. There are guidelines for safe operation of such an animal, and significant boost on 9 or 10:1 compression is typically outside what is considered "safe".

I have been told some of the early motronics used the old L-Jetronic 8 volt system, and I think the 944 is a candidate here in the early years. All the newer cars use a 5 volt system, making conversions easier for sure.

It sounds like $3,000 is what you guys would need to be able to buy if for for your car. Not sure if that is possible or not, but I can tell you the turbo can be purchased for far less than it costs to buy a centrifugal blower, so in this regard, it should be able to be done for about the same as a centrifugal blower conversion, with perhaps some added cost in the design of a manifold.

My 1983 is under cover right now, but I may take a look at it to see what kind of limitations there will be in terms of packaging. I know it can be done, since there are 30 or more of these types running around out there today.

How many of you would be interested in doing a full rebuild to pull this off and at that time get a stronger piston as part of the package?