5.0L track motor build is finally done!
05-27-2008, 04:50 AM
#77
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Glad you guys enjoyed it. I've had a grin on my face all weekend. 
The next step is to dyno this thing. We'll be playing with the cam timing and Sharktuning it.
Re: these cam lobes in Jim's GTS - I believe this is going to be a killer combo. It's what Porsche should have put in a GTS in the first place. This Elgin grind on GT cam cores will have 8º more overlap than mine. Plus the duration will be longer than the 255º of a stock GT. I'm very curious to see what a GTS can do when it's not being strangled by the stock cams.
Re: my exhaust - It's a set of Devek Level 2 headers (1-5/8" primaries), to a long Y-pipe, to a 3.5" single pipe w/ two Borla XR-1's in series.
The next step is to dyno this thing. We'll be playing with the cam timing and Sharktuning it. Re: these cam lobes in Jim's GTS - I believe this is going to be a killer combo. It's what Porsche should have put in a GTS in the first place. This Elgin grind on GT cam cores will have 8º more overlap than mine. Plus the duration will be longer than the 255º of a stock GT. I'm very curious to see what a GTS can do when it's not being strangled by the stock cams.
Re: my exhaust - It's a set of Devek Level 2 headers (1-5/8" primaries), to a long Y-pipe, to a 3.5" single pipe w/ two Borla XR-1's in series.
05-27-2008, 02:27 PM
#79
Drifting
i think you can hear the engine coming on cam in third gear in the tunnel - maybe a bit of wheelspin?? either way it sounds more agressive than a GT. im predicting more BHP than a GT with similar mods.
05-27-2008, 03:02 PM
#80
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05-27-2008, 03:30 PM
#81
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It will be very interesting to see what the dyno shows. right now, the only differences between dennis' car and mine (as well as rons) are the subtle cam design changes. (.5 more lift and more duration)
Im running under 300rwhp as of my last dyno last year, but im still suspect on the dyno strap down drag. ONE way to eliminate this, is to do the coast down test on the dynojet 248e. if you can, try and do that as well. ive only done it once, when my euro 2 valver was running 290rwhp. it turned out to be 20hp at 150mph and 10hp at near 80mph loss. if that number could go up by really cranking the car down on the dyno rack, that would explain my sudden loss of HP vs the previous dynos over 5 years. (ie near 320rwhp)
when are you going to the dyno??
mk
Im running under 300rwhp as of my last dyno last year, but im still suspect on the dyno strap down drag. ONE way to eliminate this, is to do the coast down test on the dynojet 248e. if you can, try and do that as well. ive only done it once, when my euro 2 valver was running 290rwhp. it turned out to be 20hp at 150mph and 10hp at near 80mph loss. if that number could go up by really cranking the car down on the dyno rack, that would explain my sudden loss of HP vs the previous dynos over 5 years. (ie near 320rwhp)
when are you going to the dyno??
mk
05-27-2008, 08:24 PM
#82
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It's a set of Devek Level 2 headers (1-5/8" primaries), to a long Y-pipe, to a 3.5" single pipe w/ two Borla XR-1's in series.
05-28-2008, 05:34 AM
#83
It's a set of Devek Level 2 headers (1-5/8" primaries), to a long Y-pipe, to a 3.5" single pipe w/ two Borla XR-1's in series.
If you can get a choice of dyno go for the Dyno Dynamics run in shootout mode, (it will give you a very reliable benchmark as the ramp rate is controlled by the computer, not the operater) we just had a dyno day for a Porsche club. A GT3 997 model did 268 kw which I must admit shocked me. I can't explain such a big number, a GTS auto did 178 and change and i did 219.8 kw, an early GT3 also did a similar number of 220 kw and change. The GT3 was running lean also, so it would produce a different number if it ran properly, my car which is also 5.0 but 2 valve had at its last run done 232 kw but I bumped up the timing 2 degrees and it may not have liked it.
Greg
05-28-2008, 10:29 AM
#84
Drifting
05-28-2008, 12:48 PM
#85
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I think the devek level 2 headers came in 2 sizes.
mk
mk
I believe Devek Level 11s are 1 3/4" primaries, the level ones are the 1 5/8" and are the MSDS headers.
If you can get a choice of dyno go for the Dyno Dynamics run in shootout mode, (it will give you a very reliable benchmark as the ramp rate is controlled by the computer, not the operater) we just had a dyno day for a Porsche club. A GT3 997 model did 268 kw which I must admit shocked me. I can't explain such a big number, a GTS auto did 178 and change and i did 219.8 kw, an early GT3 also did a similar number of 220 kw and change. The GT3 was running lean also, so it would produce a different number if it ran properly, my car which is also 5.0 but 2 valve had at its last run done 232 kw but I bumped up the timing 2 degrees and it may not have liked it.
Greg
If you can get a choice of dyno go for the Dyno Dynamics run in shootout mode, (it will give you a very reliable benchmark as the ramp rate is controlled by the computer, not the operater) we just had a dyno day for a Porsche club. A GT3 997 model did 268 kw which I must admit shocked me. I can't explain such a big number, a GTS auto did 178 and change and i did 219.8 kw, an early GT3 also did a similar number of 220 kw and change. The GT3 was running lean also, so it would produce a different number if it ran properly, my car which is also 5.0 but 2 valve had at its last run done 232 kw but I bumped up the timing 2 degrees and it may not have liked it.
Greg
01-12-2009, 01:36 AM
#86
Nordschleife Master
Hey guys,
Just had a couple questions on specifics of this engine relating to parts, specifically these
New main bearings w/ >180º grooved center main
Q: I assume these are the OE Porsche bearings as they seem to be the only ones available last i checked. I am curious about the grooved center main. I know some stroker guys are doing this but i also noticed that the engine Rob E is taking apart has grooves in it as well. I didn't pull the crank on my GT engine so I cant comment on what's in there. Is this something you had modified, and if so can you comment on specifics? Supplier, cost, etc?
New rod bearings
Which bearings did you use? I used Glyco, did you use the same or the OE bearings?
New piston rings
Again, what manufacturer. Mine were Goetz 928 rings with the one piece lower oil ring. Did you go with the same, or with an OE Porsche ring, or did you use a 951 ring? If 951, was it OE or OEM? Were the rings cast grey steel or chromed, was the oil ring 1 piece or 3 piece design?
Also, I dont recall reading, but did the car previously (or did you later add) an adjustable fuel pressure regulator?
Thank guys!
Just had a couple questions on specifics of this engine relating to parts, specifically these
New main bearings w/ >180º grooved center main
Q: I assume these are the OE Porsche bearings as they seem to be the only ones available last i checked. I am curious about the grooved center main. I know some stroker guys are doing this but i also noticed that the engine Rob E is taking apart has grooves in it as well. I didn't pull the crank on my GT engine so I cant comment on what's in there. Is this something you had modified, and if so can you comment on specifics? Supplier, cost, etc?
New rod bearings
Which bearings did you use? I used Glyco, did you use the same or the OE bearings?
New piston rings
Again, what manufacturer. Mine were Goetz 928 rings with the one piece lower oil ring. Did you go with the same, or with an OE Porsche ring, or did you use a 951 ring? If 951, was it OE or OEM? Were the rings cast grey steel or chromed, was the oil ring 1 piece or 3 piece design?
Also, I dont recall reading, but did the car previously (or did you later add) an adjustable fuel pressure regulator?
Thank guys!
After 10 months of work, it's finally done! We installed it this weekend and it runs!
First off, I have to say thanks to Jim Morton & Bill Ball for their generosity, hard work and patience throughout this project. It would have been impossible to do this without them. When I say impossible, I mean impossible in EVERY aspect. Here's an abridged list of the things I lacked to build this motor: any sort of practical knowledge, experience, industry contacts, tools, tools to make tools, a place to work, tow vehicle, trailer . . . you name it, I didn't have it. These guys provided all of the above and more. Basically, the Mortons - Jim, Melissa & Joe, took me in as a fourth member of the family.
All the work took place at Jim's workshop on Wednesday nights (pizza!) and weekends over the last 10 months. Engine parts were sent out to various places in California for work. Bill ferried my crank & cams several hundred miles between machine shops to magnaflux my crank and nitride my cams, just to save a few days of shipping time. Melissa baked cookies to bribe the guys doing the head work at the machine shop. Jim called in favors w/ various vendors to help move the project along. We've spent countless man-hours cleaning, measuring, modifying, assembling, timing and installing. This was an all-out assault.
This motor is as much Jim & Bill's as mine (if not more so). A lot of blood & sweat went into this project (literally) so it's a well deserved reward to see and hear this motor run. It's only going to get sweeter as we tune this thing in, dyno it, and finally track it.
As for the technical details, we tore down the old 88 S4 engine and a 26k mile 91 GT shortblock. We cleaned everything meticulously and then built up this:
91 GT 5.0L pistons & rods
91 GT block & girdle with oiling mods
91 GT crankshaft drilled by Taylor Machine
Rebalanced entire assembly
New main bearings w/ >180º grooved center main
New rod bearings
New piston rings
Ishihara-Johnson crank scraper kit & windage tray
Mike Simard's oil pickup & pan spacers
88 S4 heads shaved 0.020" for increased compression
New gaskets & seals throughout
New valve seats
New lightweight VW INA lifters, tensioner pads & IWIS chains
Elgin Cams 65-6 lobes ground on S3 cams (modified to fit S4 heads)
Ford Motorsport 24lb injectors
Hi Torque lightweight starter
Powdercoated intake and cam covers
Some pics of the journey:
And after all that, it starts & runs w/ no problems. Check out Bill's videos of the first start:
http://www.vimeo.com/976620
and the first drive.
http://www.vimeo.com/976589
If you want to see the entire gallery of pictures of this build, go to
http://gallery.lasttenth.com/main.php?g2_itemId=55
First off, I have to say thanks to Jim Morton & Bill Ball for their generosity, hard work and patience throughout this project. It would have been impossible to do this without them. When I say impossible, I mean impossible in EVERY aspect. Here's an abridged list of the things I lacked to build this motor: any sort of practical knowledge, experience, industry contacts, tools, tools to make tools, a place to work, tow vehicle, trailer . . . you name it, I didn't have it. These guys provided all of the above and more. Basically, the Mortons - Jim, Melissa & Joe, took me in as a fourth member of the family.
All the work took place at Jim's workshop on Wednesday nights (pizza!) and weekends over the last 10 months. Engine parts were sent out to various places in California for work. Bill ferried my crank & cams several hundred miles between machine shops to magnaflux my crank and nitride my cams, just to save a few days of shipping time. Melissa baked cookies to bribe the guys doing the head work at the machine shop. Jim called in favors w/ various vendors to help move the project along. We've spent countless man-hours cleaning, measuring, modifying, assembling, timing and installing. This was an all-out assault.
This motor is as much Jim & Bill's as mine (if not more so). A lot of blood & sweat went into this project (literally) so it's a well deserved reward to see and hear this motor run. It's only going to get sweeter as we tune this thing in, dyno it, and finally track it.
As for the technical details, we tore down the old 88 S4 engine and a 26k mile 91 GT shortblock. We cleaned everything meticulously and then built up this:
91 GT 5.0L pistons & rods
91 GT block & girdle with oiling mods
91 GT crankshaft drilled by Taylor Machine
Rebalanced entire assembly
New main bearings w/ >180º grooved center main
New rod bearings
New piston rings
Ishihara-Johnson crank scraper kit & windage tray
Mike Simard's oil pickup & pan spacers
88 S4 heads shaved 0.020" for increased compression
New gaskets & seals throughout
New valve seats
New lightweight VW INA lifters, tensioner pads & IWIS chains
Elgin Cams 65-6 lobes ground on S3 cams (modified to fit S4 heads)
Ford Motorsport 24lb injectors
Hi Torque lightweight starter
Powdercoated intake and cam covers
Some pics of the journey:
And after all that, it starts & runs w/ no problems. Check out Bill's videos of the first start:
http://www.vimeo.com/976620
and the first drive.
http://www.vimeo.com/976589
If you want to see the entire gallery of pictures of this build, go to
http://gallery.lasttenth.com/main.php?g2_itemId=55
01-13-2009, 03:01 AM
#88
Under the Lift
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Hopefully Dennis will see this and answer, but I believe all the parts you asked about were OE bought from 928 Intl. Yes, the center main was grooved/milled by a local machine shop similar to what Mike Simard shows here.
https://rennlist.com/forums/4427996-post18.html
https://rennlist.com/forums/4427996-post18.html
01-13-2009, 03:15 AM
#89
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Hi Ryan -
It's been about a year since the bottom end went together so I might be a little hazy on what we did. I hope Jim or Bill will correct me if I'm wrong . . .
We had to groove the center main to supply the crank center main journal. Taylor Engine cross-drilled the center main and linked it to the 2-6 & 3-7 rod journals. IIRC the stock center main bearing shells are not grooved and have only the two oil supply holes on the lower half. I bought the stock OE bearing shells. The top shell was then grooved completely and the lower shell was grooved from the oiling holes to the ends. The top half was grooved by a local machine shop (Tri Valley) and Jim grooved the bottom half.
Yes, Glyco bearings were used. Their thicknesses were measured before deciding the clearances.
I bought the stock Goetz 928S4 rings. IIRC the lower rings were one-piece.
When the headers were installed on the car by the previous owner 8+ years ago, an adjustable fuel pressure regulator was installed at the same time. We kept the same setup but used 24lb injectors.
Hope this helps.
It's been about a year since the bottom end went together so I might be a little hazy on what we did. I hope Jim or Bill will correct me if I'm wrong . . .
New main bearings w/ >180º grooved center main
Q: I assume these are the OE Porsche bearings as they seem to be the only ones available last i checked. I am curious about the grooved center main. I know some stroker guys are doing this but i also noticed that the engine Rob E is taking apart has grooves in it as well. I didn't pull the crank on my GT engine so I cant comment on what's in there. Is this something you had modified, and if so can you comment on specifics? Supplier, cost, etc?
Q: I assume these are the OE Porsche bearings as they seem to be the only ones available last i checked. I am curious about the grooved center main. I know some stroker guys are doing this but i also noticed that the engine Rob E is taking apart has grooves in it as well. I didn't pull the crank on my GT engine so I cant comment on what's in there. Is this something you had modified, and if so can you comment on specifics? Supplier, cost, etc?
New rod bearings
Which bearings did you use? I used Glyco, did you use the same or the OE bearings?
Which bearings did you use? I used Glyco, did you use the same or the OE bearings?
New piston rings
Again, what manufacturer. Mine were Goetz 928 rings with the one piece lower oil ring. Did you go with the same, or with an OE Porsche ring, or did you use a 951 ring? If 951, was it OE or OEM? Were the rings cast grey steel or chromed, was the oil ring 1 piece or 3 piece design?
Again, what manufacturer. Mine were Goetz 928 rings with the one piece lower oil ring. Did you go with the same, or with an OE Porsche ring, or did you use a 951 ring? If 951, was it OE or OEM? Were the rings cast grey steel or chromed, was the oil ring 1 piece or 3 piece design?
Also, I dont recall reading, but did the car previously (or did you later add) an adjustable fuel pressure regulator?
Thank guys!
Thank guys!
Hope this helps.
