Stock 951 tranny abilities
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Stock 951 tranny abilities
My car is almost done. The first thing I had done was the transmission. Completely rebuilt... new shims, bearings, etc. I also replaced the ring and pinioin with a Porsche Racing 8:31 and went to a Quaife LSD. The engine was just completed and turned into a 3.0 liter. I expect after some breaking in and final upgrades I will reach close to 500 horse at the tires. All along I have been told that the transmission will handle the power "no problem". However, I learned yesterday that the stock transmission may not handle this power. How worried should I be and are there other things I can do other than just being gentle in my shifting to help keep my transmission intact?
Thanks in advance.
Thanks in advance.
#4
Originally Posted by Blackus Amongus
My car is almost done. The first thing I had done was the transmission. Completely rebuilt... new shims, bearings, etc. I also replaced the ring and pinioin with a Porsche Racing 8:31 and went to a Quaife LSD. The engine was just completed and turned into a 3.0 liter. I expect after some breaking in and final upgrades I will reach close to 500 horse at the tires. All along I have been told that the transmission will handle the power "no problem". However, I learned yesterday that the stock transmission may not handle this power. How worried should I be and are there other things I can do other than just being gentle in my shifting to help keep my transmission intact?
Thanks in advance.
Thanks in advance.
#5
Originally Posted by jakery
Mike, What does "power" shift really mean, or does it just vaguely mean quick shifting?
Also refered to as "no-lift-shift" You never let off the power, even when clutching in.
#6
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The 8:31 is the standard S2 3.875 R/P, its not a special "racing" set out of the Motorsports parts bin. But that said, it is pretty strong and is has been known to handle high horsepower applications.
Impact/shock loading is what will cause damage. So as Mike said, avoid power shifting and hard launches, or you can expect to launch the trans... Otherwise, it should hold up.
Impact/shock loading is what will cause damage. So as Mike said, avoid power shifting and hard launches, or you can expect to launch the trans... Otherwise, it should hold up.
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Originally Posted by MPD47
I consider power shifting, WOT shifting, it's incredibly bad for transmissions.
Also refered to as "no-lift-shift" You never let off the power, even when clutching in.
Also refered to as "no-lift-shift" You never let off the power, even when clutching in.
#9
Or you could just not flat foot it. The only reason you need that extra ooomph is if you're drag racing. Let's be honest, if you're drag racing, you know you're buying a new trans.
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Originally Posted by Blackus Amongus
My car is almost done. The first thing I had done was the transmission. Completely rebuilt... new shims, bearings, etc. I also replaced the ring and pinioin with a Porsche Racing 8:31 and went to a Quaife LSD. The engine was just completed and turned into a 3.0 liter. I expect after some breaking in and final upgrades I will reach close to 500 horse at the tires. All along I have been told that the transmission will handle the power "no problem". However, I learned yesterday that the stock transmission may not handle this power. How worried should I be and are there other things I can do other than just being gentle in my shifting to help keep my transmission intact?
Onto the tranny topic. If you don't mind me asking, who is this source that told you the stock tranny may not hold 500 RWHP? I'm just curious, that's all. As some people have said, one of the best way to preserve any tranny, let alone a 3.0L 951, is the manner in which you drive it. Your driving style will dictate a lot on how long it lasts. As Mike showed you, if you are dumping the clutch, doing hard lanuches, you "will" have problems in due time. Then again this should be expected with any big RWHP car.
Personally, I know of 3 people who have "big" (easily 450+) RWHP 951s that run them mostly on the street, and track too. I have yet to hear of any of them having any tranny issues that I'm aware of. And having owned one myself, I didn't have any myself. Then again, I'm not hard on my car at all, and always take care of my equipment. Anyway I honestly I don't think you'll have an issue if you don't "abuse" the car in any manner. So, tell us more about your project car, and post some pics so we have some nice eye-candy to look at! Good luck with it too. If you need any help, we have a lot of people here that would be more than willing to assist you with your beast!
#11
In the drag bike world they do an interesting thing to "powershift" trans
by briefly cutting spark (ignition) in conjunction with air shift, they are able to shift under load without clutching. Totally different but interesting aproach. Would be interesting to do a similar spark cut to accomodate powershifting in automotive realm
by briefly cutting spark (ignition) in conjunction with air shift, they are able to shift under load without clutching. Totally different but interesting aproach. Would be interesting to do a similar spark cut to accomodate powershifting in automotive realm
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Here is a quick summary. Although not complete. Also, a couple of pictures. I will show more when I get the car back. It is in great cosmetic condition, but I want to repaint it anyways and add some body stuff. Here goes…
BBS 8.5 X 18” RS-GT’s front with Michelin Pilot Sport PS2’s, BBS 10 X 18” RS-GT’s rear with Michelin Pilot Sport PS2’s, Bilstein Cup series coil-overs all around(coils by Hyperco), Lindsey adjustable camber plates, all new bearings and bushings, new tie rods and boots, Big Blacks up front with Pagid oranges, rebuilt and painted rear calipers with Pagid oranges, 928 biasing valve, SS break lines, new master and slave cylinders, replaced control arms and caster blocks with Racers Edge, Weltmeister anti-sway bars front and rear, KLA strut brace, completely rebuilt transmission with all new shims and bearings, new 8:31 ring and pinion, new Quaife LSD, Kokeln short shift, new throw out bearing and fork, custom 104mm bore Darton steel sleeves with O-rings in block, new ARP head studs, custom 88mm, knife-edged, cross-drilled, balanced, nitrided, and micro polished crank, custom 104mm 8:1 compression JE Racing forged pistons (rings & pins included), Pauter connecting rods, new main, rod, and balance shaft bearings, port, polish, and O-ring cylinder head and perform complete competition valve job, wide fire ring head gasket, new ARP washers & nuts, cylinder head and torque, rebuild oil pump and install, new water pump, new cam and balance shaft adjuster pulleys and idler rollers, new cam and balance shaft belts, all new seals and gaskets, port match intake manifold to head intake ports, custom ceramic coated racing 321 stainless equal length racing headers with V-band clamps, custom racing ceramic coated 321 stainless cross-over pipe to turbine, Turbonetics T04E/super 60, stage 5 ceramic ball bearing turbine (good to 500 HP), TiAL 46mm adjustable wastegate, TiAL blow-off valve, fab and install 2.5” polished aluminum boost tubes, silicone (fiberglass reinforced) boost hoses and vacuum hose throughout, custom racing Intercooler (good to 600HP), high polish oil pan, high polish cam tower, high polish intake manifold, 968 oil pickup tube, 968 oil pan baffle, full race cam, race valve springs, titanium retainers, new hydraulic lifters, all new yellow chromium plated hardware, race clutch – KEP aluminum pressure plate, full 3” stainless turbine back exhaust(dual tip), 88 pound RC engineering injectors (blueprinted), adjustable fuel pressure regulator, braded fuel lines, rail mounted fuel pressure gauge, new oil filter, new plug wires, W3DPO spark plugs, under-drive pulley kit, new stock radiator, new starter, Lindsey Power Perfect management system(to be upgraded), Autothority 30C MAF(will be upgraded to Lindsey 36C), Weltmeister chips(came with car and will be upgraded) and lots and lots of interior and electrical stuff.
More to come.
BBS 8.5 X 18” RS-GT’s front with Michelin Pilot Sport PS2’s, BBS 10 X 18” RS-GT’s rear with Michelin Pilot Sport PS2’s, Bilstein Cup series coil-overs all around(coils by Hyperco), Lindsey adjustable camber plates, all new bearings and bushings, new tie rods and boots, Big Blacks up front with Pagid oranges, rebuilt and painted rear calipers with Pagid oranges, 928 biasing valve, SS break lines, new master and slave cylinders, replaced control arms and caster blocks with Racers Edge, Weltmeister anti-sway bars front and rear, KLA strut brace, completely rebuilt transmission with all new shims and bearings, new 8:31 ring and pinion, new Quaife LSD, Kokeln short shift, new throw out bearing and fork, custom 104mm bore Darton steel sleeves with O-rings in block, new ARP head studs, custom 88mm, knife-edged, cross-drilled, balanced, nitrided, and micro polished crank, custom 104mm 8:1 compression JE Racing forged pistons (rings & pins included), Pauter connecting rods, new main, rod, and balance shaft bearings, port, polish, and O-ring cylinder head and perform complete competition valve job, wide fire ring head gasket, new ARP washers & nuts, cylinder head and torque, rebuild oil pump and install, new water pump, new cam and balance shaft adjuster pulleys and idler rollers, new cam and balance shaft belts, all new seals and gaskets, port match intake manifold to head intake ports, custom ceramic coated racing 321 stainless equal length racing headers with V-band clamps, custom racing ceramic coated 321 stainless cross-over pipe to turbine, Turbonetics T04E/super 60, stage 5 ceramic ball bearing turbine (good to 500 HP), TiAL 46mm adjustable wastegate, TiAL blow-off valve, fab and install 2.5” polished aluminum boost tubes, silicone (fiberglass reinforced) boost hoses and vacuum hose throughout, custom racing Intercooler (good to 600HP), high polish oil pan, high polish cam tower, high polish intake manifold, 968 oil pickup tube, 968 oil pan baffle, full race cam, race valve springs, titanium retainers, new hydraulic lifters, all new yellow chromium plated hardware, race clutch – KEP aluminum pressure plate, full 3” stainless turbine back exhaust(dual tip), 88 pound RC engineering injectors (blueprinted), adjustable fuel pressure regulator, braded fuel lines, rail mounted fuel pressure gauge, new oil filter, new plug wires, W3DPO spark plugs, under-drive pulley kit, new stock radiator, new starter, Lindsey Power Perfect management system(to be upgraded), Autothority 30C MAF(will be upgraded to Lindsey 36C), Weltmeister chips(came with car and will be upgraded) and lots and lots of interior and electrical stuff.
More to come.
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Oh and thanks for the welcome. I did not know you guys even existed until recent. I will be tracking this car 3 to 5 times a year and every weekend on the street.
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Originally Posted by 2bridges
In the drag bike world they do an interesting thing to "powershift" trans
by briefly cutting spark (ignition) in conjunction with air shift, they are able to shift under load without clutching. Totally different but interesting aproach. Would be interesting to do a similar spark cut to accomodate powershifting in automotive realm
by briefly cutting spark (ignition) in conjunction with air shift, they are able to shift under load without clutching. Totally different but interesting aproach. Would be interesting to do a similar spark cut to accomodate powershifting in automotive realm
I just set mine up last night. It is sweet!
Rogue