Those Interested in Turbocharging your L-Jetronic 928 read here...
02-23-2004, 02:03 PM
#1
Three Wheelin'
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Those Interested in Turbocharging your L-Jetronic 928 read here...
I have decided to start development of another turbocharged 928 project this winter/ spring. At present, I have a doner engine coming from Texas out of a 1982 928, i.e. M28.15, my personal favorite 
and the one I know the best! It was a casualty of a Chevy engine swap and only has 75,000 on the clock. This will be the "jig and fixture" for the setup, because I hate being on a cold concrete floor in the dead of winter.
Anyway, this unit is going to get fitted with a VERY high flow Garrett Hybrid turbo that is not only durable, but extremely cost effective. This will be a single turbocharged 928 and the turbocharger itself will be able to support 600 or so HP. I am not going to make HP claims on this engine (I've wasted enough time on here arguing over the last 8 months), but I will go in and say it will be at least as powerful (lb. for lb.) as the Bastard, or should I now call it Bastard I? Just for starters, the wheel is about 8% more efficient than what is in my car now.
So, here is the deal. I am going to build this setup, then locate a doner car for installation of the setup. Once that is done, I plan to bring the car to Kansas this summer and offer it for sale, turn key. That is if I can pull it all off in that time frame. Timing is tight to say the least, but it is possible. It will have the full deal, manifolds, intercooler, Garrett turbo, Tial Wastegate, fuel curve management, high flow exhaust... you all know the drill. We have not yet decided on a boost level, but the prototype will run at least 8-10 lbs. Trust me, I will not be afraid to turn the screw down on this one as there will be zero personal attachment. This will be a thoroughly engineered system, not a pile of parts.
For those serious about purchasing the components in kit form to bolt onto a properly prepared 928 let me know. Cost will be similar to the Vortech kits floating around out there. I know some of you have inquired about making your own setup, and others have asked for assistance along the way. If you are looking to run something on top of the stock 928 engine, I will make a guess and say 6 lbs on a 83-84 and 8-9 lbs on an 80-82 should be easily possible. For those who want to spend the time and cash on a lower end upgrade, 14-16 lbs won't be out of the question.
Cheers!
and the one I know the best! It was a casualty of a Chevy engine swap and only has 75,000 on the clock. This will be the "jig and fixture" for the setup, because I hate being on a cold concrete floor in the dead of winter.Anyway, this unit is going to get fitted with a VERY high flow Garrett Hybrid turbo that is not only durable, but extremely cost effective. This will be a single turbocharged 928 and the turbocharger itself will be able to support 600 or so HP. I am not going to make HP claims on this engine (I've wasted enough time on here arguing over the last 8 months), but I will go in and say it will be at least as powerful (lb. for lb.) as the Bastard, or should I now call it Bastard I? Just for starters, the wheel is about 8% more efficient than what is in my car now.
So, here is the deal. I am going to build this setup, then locate a doner car for installation of the setup. Once that is done, I plan to bring the car to Kansas this summer and offer it for sale, turn key. That is if I can pull it all off in that time frame. Timing is tight to say the least, but it is possible. It will have the full deal, manifolds, intercooler, Garrett turbo, Tial Wastegate, fuel curve management, high flow exhaust... you all know the drill. We have not yet decided on a boost level, but the prototype will run at least 8-10 lbs. Trust me, I will not be afraid to turn the screw down on this one as there will be zero personal attachment. This will be a thoroughly engineered system, not a pile of parts.
For those serious about purchasing the components in kit form to bolt onto a properly prepared 928 let me know. Cost will be similar to the Vortech kits floating around out there. I know some of you have inquired about making your own setup, and others have asked for assistance along the way. If you are looking to run something on top of the stock 928 engine, I will make a guess and say 6 lbs on a 83-84 and 8-9 lbs on an 80-82 should be easily possible. For those who want to spend the time and cash on a lower end upgrade, 14-16 lbs won't be out of the question.
Cheers!
02-23-2004, 02:10 PM
#3
Administrator - "Tyson"
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Good luck John. Hope to see you (and Bastard II) in Kansas!
One question, why the lower boost on the 83-84? Due to higher compression?
One question, why the lower boost on the 83-84? Due to higher compression?
02-23-2004, 05:19 PM
#7
Administrator - "Tyson"
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Wow, heinrich and heinrich are both interested!
Sorry, slow day today.
Sorry, slow day today.
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02-23-2004, 06:08 PM
#9
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John, good luck on the project. Let me know if there is anything I can help with. My current single turbo setup has @ 30K miles and still running strong. I can post pictures of my setup if they would be of any help in/durring your fabrication journeys.
SilverSFR
SilverSFR
02-23-2004, 06:58 PM
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Three Wheelin'
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Now now, I can't give away all the secrets. There is still a lot of conceptual work to be done. The goal will be to keep the stock aircleaner system so the top side will look essentially stock. Air conditioning will not be disturbed. Still tossing around the intercooler concepts, though my gut tells my air to air is the best way to go for the setup.
I am playing with some manifold concepts and location of components. We expect this car to come on boost strong and hard at about 2600 rpm and pull like a freight train to redline.
Engineering and detailing of components to send to the laser cutter will probably start this weekend. I still need to get my hands on a welder to make the manifolds, though I may just send them to a old friend who is fluent in TIG after I tack them up.
RE on the boost levels...yes it is about the CR. I feel confident these engines can handle 6-9 lbs if properly set up. The car will run very responsively on just 5 lbs of boost and that will easily get you to 928 S4 levels of power and performance with more in the torque department. With 8-9 lbs you are looking at a 350 crankshaft HP car with no head or cam work whatsoever.
The goal isn't to post a super-man dyno number, but to create a smooth streetable 928 with some very desirable performance that is also reliable. If you want to build a crazy HP 928 then you should really be looking to prepare the bottom end to take the pounding. I believe this induction system will support quite a bit of power when it is all said and done.
The nice part is I think I can retain the look of the top side of the engine, one of the nicest things about looking at a 928.
I am playing with some manifold concepts and location of components. We expect this car to come on boost strong and hard at about 2600 rpm and pull like a freight train to redline.
Engineering and detailing of components to send to the laser cutter will probably start this weekend. I still need to get my hands on a welder to make the manifolds, though I may just send them to a old friend who is fluent in TIG after I tack them up.
RE on the boost levels...yes it is about the CR. I feel confident these engines can handle 6-9 lbs if properly set up. The car will run very responsively on just 5 lbs of boost and that will easily get you to 928 S4 levels of power and performance with more in the torque department. With 8-9 lbs you are looking at a 350 crankshaft HP car with no head or cam work whatsoever.
The goal isn't to post a super-man dyno number, but to create a smooth streetable 928 with some very desirable performance that is also reliable. If you want to build a crazy HP 928 then you should really be looking to prepare the bottom end to take the pounding. I believe this induction system will support quite a bit of power when it is all said and done.
The nice part is I think I can retain the look of the top side of the engine, one of the nicest things about looking at a 928.
02-23-2004, 09:06 PM
#12
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BCdavis, Every extra cent i can get past my wife has gone into fixing or replaceing parts and more parts. I now have have everything working perfectly. Call me chicken, but I have not put my 928 on the Dyno. math tells me that @ 7 lbs of boost I should getting and extra 80 to 100 HP's.
With so few turbo, 62K, 5-speed, 928's around, I sure would hate to screw this one up.
SilverSFR
With so few turbo, 62K, 5-speed, 928's around, I sure would hate to screw this one up.
SilverSFR
02-23-2004, 09:31 PM
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As long as it's working, and you're having fun with it, then it is successful.
People just like to get an idea of what kind of improvements certain modifications will create.
Since there are so few turbo 928s out there, it is nice to get the numbers.
Maybe in a few years, you will get on the car hard enough to see that it can take
a few high rpm runs without self-destructing, and you will be willing to run in
on the dyno.
But until then, enjoy!
People just like to get an idea of what kind of improvements certain modifications will create.
Since there are so few turbo 928s out there, it is nice to get the numbers.
Maybe in a few years, you will get on the car hard enough to see that it can take
a few high rpm runs without self-destructing, and you will be willing to run in
on the dyno.
But until then, enjoy!
