993 3.8 RSR Engine Build
#1
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993 3.8 RSR Engine Build
This project started because my track car was burning more oil than normal. Fred Gear at Porsche Birmingham does my track set up and anything needed with my car. We thought it was valve guides and decided to add some power while we were in there. I spoke with a couple of companies here in the US and also contacted Colin at Ninemeister in UK. I decided to go with his 9m 993+2 kit that consisted of billet aluminum heads, cams, light weight flywheel and some other things. As my builder got into the engine he found a lot of wear on the cylinders and rings, so I figured while we were in there we may as well do a 3.8 build. I wanted to maximize my horsepower and torque but still wanted a reliable engine. After many discussions with Colin at Ninemeister we decided to build a race engine.
#2
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After several recommendations for rennlisters, I sent the case off to Ollie's Machine Shop in Arizona to have 3.8 bore, machine cut O-rings, boat tailed the mains, shuffle pins, moon cut the cylinders and machined the case for the new GT3 oil pump. Several race shops told me that the slip fit cylinders would be fine but Ninemeister and a couple other race shops said the race engine would not last as long unless I did the machine fit which cost more money and time. I decided to go with the Mahle 109mm cylinders and the Mahle 102mm RSR pistons
Before and after Ollie's moon cut the cylinders
Correct Mahle 3.8 993 RSR piston. Originally the incorrect pistons with higher compression were sent to me. While discussing my upcoming tune and the project, Jeff Gamroth at Rothsport saved me on this one. He asked to see a photo and told me the pistons I had were the wrong pistons so my supplier replaced them.
Before and after Ollie's moon cut the cylinders
Correct Mahle 3.8 993 RSR piston. Originally the incorrect pistons with higher compression were sent to me. While discussing my upcoming tune and the project, Jeff Gamroth at Rothsport saved me on this one. He asked to see a photo and told me the pistons I had were the wrong pistons so my supplier replaced them.
Last edited by Tripp993; 07-14-2018 at 02:43 PM.
#3
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Ninemeister provided these Rods to fit GT3 crank, DLC coated race rockers, shafts and elephants foot adjusters and race cams.
Ninemeister Racing Lightweight Rods to fit GT3 crank
Ninemeister new DLC coated race rockers, rocker shafts and elephant foot adjusters
New Race Cams
Case was machined to fit new GT3 Oil Pump
New GT3 crank and 9m Rods
Old 993 Oil Pump vs. New GT3 Oil Pump
Ninemeister Racing Lightweight Rods to fit GT3 crank
Ninemeister new DLC coated race rockers, rocker shafts and elephant foot adjusters
New Race Cams
Case was machined to fit new GT3 Oil Pump
New GT3 crank and 9m Rods
Old 993 Oil Pump vs. New GT3 Oil Pump
#4
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Old worn 993 cylinders and rings
New Mahle cylinders and rings. Much tighter fit!
Cylinders and pistons being installed
New Mahle 109mm cylinders and 993 102mm RSR pistons.
Last edited by Tripp993; 07-14-2018 at 02:44 PM.
#5
Thanks for sharing. I’ll be watching as this goes along
#6
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what is the build cost of this as you plan it? my guess $35k... lemme know if i am close
and what is the expected increase in hp and tq? debating a similar undertaking on a 964 motor
and what is the expected increase in hp and tq? debating a similar undertaking on a 964 motor
#7
Fantastic build. Are you sure the pistons are 103mm, and not 102mm? Mahle 3.8 are 102mm (making, IIRC, 3.746L displacement) the last I did one of these builds some years ago. But maybe they added a mm and are finally making a true 3.8 p/c? What compression are you running? And how are you handling engine management, are you flashing the ECU or going Motec? Congrats, will be a great motor. I've driven these. Lots of fun.
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#8
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I'm in the automotive business and get discounts on some of these parts and labor but still almost double your guess. You can definitely do a build for less and certainly for more too but a lessor build may not be this extreme. I wanted the best parts and wanted to make sure it was going to hold up on the track and last a long time. I also have a Motec system and Rothsport intake I'm adding to this. I will post dyno results within the next 3 weeks after the tune.
#9
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Thread Starter
Fantastic build. Are you sure the pistons are 103mm, and not 102mm? Mahle 3.8 are 102mm (making, IIRC, 3.746L displacement) the last I did one of these builds some years ago. But maybe they added a mm and are finally making a true 3.8 p/c? What compression are you running? And how are you handling engine management, are you flashing the ECU or going Motec? Congrats, will be a great motor. I've driven these. Lots of fun.
#11
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We were going for at least 0.02mm cam deviation between the two but were able to get them set at 0.0mm deviation between the 2.
Rothsport Racing custom equal length headers
Rennline upper and lower valve covers finish this engine off nicely.
#14
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Join Date: Sep 2008
Location: Flyoverland - Central, Ohio
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Subscribed. Got love a good 993 air-cooled engine project thread.
Glad to see others DEing and pushing the limits on the 993 platform. Colin @ 9M is a great resource for the 993 community.
Did you do a Dyno run before the project to get a before/after compare?
Glad to see others DEing and pushing the limits on the 993 platform. Colin @ 9M is a great resource for the 993 community.
Did you do a Dyno run before the project to get a before/after compare?