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================ ================ Transmissions Clutches & Flywheels ================ ================ ================ ================ ================ 996-996 TT & Boxster Components ================ Useful Technical and Reference Information Click on the PERFORMANCE UPGRADES you want to learn about.
© 1998-2007 Rennsport Systems Updated 4/15/07 |
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Street Performance and Racing Engines as well as Machine Shop Services- We can rebuild your engine or supply complete
engines for street or track use. All customer's powerplants are built to each
person's needs and budgetary requirements. Engines can be dyno'ed and these
are shipped with a computer printout of horsepower and torque. Special engine
sizes are one of our specialties. We carry
Brad-Penn 20w-50 Racing oil!! Transmission Rebuilding & Close-ratio Gearsets-Light Flywheels- One of our specialties is transmissions. Rennsport Systems will overhaul and re-gear any 901-915-930-G50 gearbox for much better street performance as well as racing applications. This makes any Porsche much for fun to drive and the performance increase is similar to a 50 HP power increase. Transmissions that are severely stressed by high-horsepower engines will require a pressure lubrication system for maxinum longevity. We also offer aluminum flywheels that are half the weight of the OEM flywheel for street and race cars; Lowering the reciprocating weight helps the car shift faster and eases the loads on the syncronizers. There is also a race-only extremely lightweight racing clutch assembly for 901-equipped Porsches. Suspension Components and Integrated Systems- Suspension upgrades are a cost effective method of improving your Porsche's handling. This will reduce the body roll and fore-aft pitching motions created by acceleration and braking. Enhancing car control is the main objective in any suspension improvement program. Suspensions should be modified as a system of integrated parts, not just a package of bolt-ons. This ensures that everything will work together. Spring rates must be matched to shock valving and swaybar sizes must compliment the spring rates. To this end, Rennsport Systems can design a suspension upgrade package to suit your car's usage whether its a daily driver, weekend hobby car or dedicated track racer. Brake Upgrades- One of the most important improvements to any Porsche is improved braking performance. This can be accomplished by installing better Brake Pads, Racing Brake Fluid, Cooling Kits, Larger Calipers & Rotors and even Stainless Steel Brake lines. We offer various upgrades for all models from simple caliper replacements to complete racing brake systems for high-horsepower vehicles. Brakes MUST be designed and installed with compatible components so that the car's braking balance isn't disturbed. Front-to-rear brake bias can be adjusted by sizing the proper calipers and master cylinders as well as manual brake bias control. The biggest and best brakes will not work properly without adequate rotor cooling so we offer several brake cooling options. Professional references supplied gladly. ================================= A word about rebuilt-overhauled engines: "Rebuilt"
- Reconditioned"…………What do they mean? These words have
different meanings for each individual, and nobody seems to know exactly what
their expectations should be. The word "rebuilt" is often bandied
about when an engine is to be rebuilt. I would like to offer some advice and
the benefit of some professional experience in this field. "Rebuilt"
can be used to describe a whole range of conditions that range from
"like-new" to "simply cleaner." One must carefully decide
what constitutes truly "rebuilt." There are some
parts should never be rebuilt and others that can be reconditioned to extend
their lifespan. For example, pistons can’t be rebuilt any more than
sparkplugs can be. If a piston is worn enough for the piston-to-cylinder wall
clearance to be at or near tolerance or the ring-land grooves are found to be
too wide for new rings, its best to replace the pistons with new parts. Brake calipers,
alternators, starters and the like can have some internal parts replaced to
make them function again without spending the money for an entire new unit.
For those folks who are on a strict budget (and who isn’t?), this may be an
acceptable short-term solution until a more permanent repair can be made.
Certain fuel-injection parts can be changed without incurring large labor
costs, and their performance can be monitored easily in case the
rebuilt/reconditioned part doesn’t last very long. Other items are penny-wise
and pound-foolish to rebuild if they are labor-intensive to change/repair or
have dire consequences if they fail at an inconvenient time or place. A good example
might be installing a used or rebuilt fuel pump. The folly of using a rebuilt
fuel pump becomes obvious when you are stranded 200 miles from a replacement.
The same can be said of using a rebuilt clutch that fails when you are far
away from a shop that can install a new one. Some items simply shouldn’t be
rebuilt when you are using your car at or near its limit on the track or
street. Wheel bearings, brake parts, and some suspension parts fall into this
category. The single most
expensive part of any Porsche is its engine. Everyone has his or her own
expectation of how long a "rebuilt" engine should last before
needing to be disassembled once again, and a "rebuilt" engine can
last anywhere from 5,000 to 200,000 miles depending upon what new parts were
used in the rebuild and who performed it. For a street
engine, we feel that a proper rebuild should last as long or even longer than
the original OEM powerplant. To this end, certain parts cannot be reused if
the owner expects the rebuilt engine to perform as new and be as durable as
the original Factory engine. Considering the normal labor charged by dealers,
independent shops or high-performance specialists, this is a reasonable
expectation. Our shop charges 32-45 hours of time to disassemble, clean,
rebuild, and reassemble an entire engine. (The variation exists between
naturally aspirated and turbocharged engines.) This figure doesn’t vary much,
since it takes the same amount of time to measure, install and set up
everything regardless of whether it’s a ‘70s 2.2 or a late-‘80s 3.6. If a "rebuild"
can cost as little as $4,000 or as much as $12,000 with the labor to do this
job properly, then the difference lies in the cost of the parts that were
used during this job—in the case of Porsches generally a function of whether
the parts were new or reconditioned, OEM or cheap substitutes. Repairing an
otherwise fine engine is a different thing altogether. For instance, many 3.2
and 3.6 litre engines simply need new valve guides to reach their potential
lifespan and to that end, a top overhaul may be all that is necessary. It
would be irresponsible for the shop not to also inspect and replace any worn
valves and check the valve springs for proper seat pressures. Nikasil
cylinders last a very long time, and in some cases, a simple ring replacement
will ensure that the engine has good compression until major overhaul time if
the pistons are still serviceable. It’s important to
realize that when it’s time to rebuild the engine "as new", using
"recycled" or worn parts is not economical or prudent if you wish
to achieve the maximum engine life and restore the original performance to
the car. There are no shortcuts, whatsoever. An honest-to-God
rebuilt engine should have new internals to perform as such and last as long.
Here are just a few of the parts that we would replace with new—not
"reconditioned"--ones: Pistons, rings
& cylinders Valves (as
needed) Valve springs Valve guides
& seals Cam chains and
ramps Chain sprockets
and idlers Intermediate
gears (as needed) Chain tensioners All engine
bearings New rod bolts and
pin bushings This doesn’t
include machine work and other operations to ensure that the engine is in
as-new condition or any modifications made to increase performance. So when you
select a shop to rebuild the engine in your Porsche, here are some things to
think about: 1) Labor is a
small part of the total cost of a proper rebuild. If the overall cost looks
too good to be true, then something is wrong. New OEM Porsche parts are not
cheap. You get what you pay for. Never overlook the experience required for a
quality rebuild of ANY 911 engine. 2) Ask the shop
whether they use new or reconditioned parts. What parts ARE new? What machine
work do they do? You must have full confidence in the shop that performs the work
for you, and whether or not the owners are nice guys is immaterial. They must
be competent and honest. 3) Get references
from previous customers. Porsche ownership is an extended family, and there
are some great resources out there through the PCA, so use them. The National
Tech Committee is just one of them at your disposal. Talk to people who KNOW
engines, not just another person who may not know any more than you do about
this subject. This takes legwork and diligence. Remember, its your money that’s
at stake! 4) Nobody likes
to be without their "baby" for any longer than necessary, but be
wary of anyone who promises short turnaround times. It simply _takes_time_to
do this entire job properly and these engines are not as simple to do as an
American V-8. Porsche ownership comes at a premium, and you expect
appropriate levels of engineering and execution. Don’t be in a hurry. If you
need cardiac-bypass surgery, should time the most important criterion
or having the job done correctly?
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