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Looking to upgrade my '94 968 for the track - PICS

 
Old 01-24-2019, 05:34 PM
  #16  
Kiltacular Jim
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Originally Posted by 951and944S View Post
I have the best email contact on my work PC that I can get to you Wed after holidays.

If you want, I could send them an email with your contact tagged and get them to reply directly to you explaining all the features of the set you are interested in learning more about.

T
I'd very much like to look into their road kit as well, if you could PM me with details -- I sent you mine.
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Old 01-24-2019, 08:42 PM
  #17  
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I run 18-285/30-r and 18-245/35-f on Hoosiers on enkeiĺs. Tarrett sway bar on the front. Full cage with fire suppression. Balance shaft out. Magnaflow exhaust. Racing cams. j&E pistons, Woosner rods, decked block, Cloud and I have gone back and forth on staggered vs. square. Might be a personal preference.
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Old 01-24-2019, 09:55 PM
  #18  
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Rap - I have a question. I've heard of people removing the balance shafts. Can you explain the advantage? And what's a decked block? Please excuse my ignorance!
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Old 01-24-2019, 10:42 PM
  #19  
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A block is cut down to get a good gasket seal. Balance shaft comes out because it can break and Weight reduction. No question is ignorant.
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Old 01-25-2019, 02:48 AM
  #20  
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I didn't know you were running a balance shaft delete set-up. Have you noticed a higher level of vibrations? Are you also running a single mass flywheel? What about a harmonic balancer up front? I'd worry about the longevity of the torque tube and its bearings if you were to increase the vibration levels too much, but Pete definitely knows what he's doing.

I think either a staggered or square set-up can be made to work just fine - you just have to balance the front/rear spring rates, sway bar stiffness, and shock settings to compensate. I just like being able to rotate my tires to get more life out of them, as tires are the biggest consumable cost of this hobby. You have a lot of nice mods on your car.
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Old 01-25-2019, 03:43 AM
  #21  
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A decked block also promotes a higher compression ratio...

-Yogii
AKA 968 Virgin
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Old 01-25-2019, 08:31 AM
  #22  
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Bingo. Cloud the balance shaft came out after I cracked the balance shaft housing at the Glen. Max felt it was appropriate. Yes to the flywheel and no vibrations. Last year was a mass of problems including a tranny implosion at my last event at Summit. I rotate my tires, side to side of course after about 6 runs. You and I have had many tire setup discussions so I won’t bore the membership here!
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Old 01-25-2019, 10:34 AM
  #23  
951and944S
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Originally Posted by Isaacsracing View Post
Rap - I have a question. I've heard of people removing the balance shafts. Can you explain the advantage? And what's a decked block? Please excuse my ignorance!
Decking the block used to true the top surface of the block, but moreso, to set a custom desired position of the piston at TDC vs. the height of the block.

Our blocks are pretty consistent between one and the next, but while configuring compression, piston ccs, head gasket/valve clearance, etc, it's a good idea to measure your block from the crank centerline, easy on the 4cyl because the measurement is taken from the block flat surface where the lower crankcase (girdle) bolts to and to the top surface where the head gasket is placed.

Once you know this dimension precisely, you take your known measurements of - rod length center to center + 1/2 of crankshaft stroke, + height of piston from pin center = XX
Take xx and subtract it from the deck height explained above.
You can have your machinist take that exact amount off if you want your piston to be flush with deck, or even more if you want your piston to be proud of block deck.

There is another advantage to removing the balance shafts, and that is, reducing the duty requirement of the oil pump output, since you are now plugging what probably equates to at least a 3/8" hole (2 x 3/16") oil delivery to the balance shafts that further taxes the oil system.
It's my belief (and I am doing this on my own engines) that you can even lessen the dimension on the #3 main bearing feed hole since it no longer has to feed the shafts, and is only lubed as a thrust bearing for the crank since this main journal is the only 1/5 that does not feed a rod.

T
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Old 01-25-2019, 04:11 PM
  #24  
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So do you feel that removing the balance shafts on a 3.0 liter is safe? I worry about the return of the harmonics they're designed to reduce putting additional strain on our drivelines, particularly the torque tube and bearings. As has been discussed in another thread, repairs, particularly on a split TT like mine, are far from trivial!

By the way, I have Pauter "lightweight" forged rods and Wossner pistons, so I have lighter rotating mass than a stock 3.0 liter.
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