Help me select the correct upgrades for my engine...

[Kroggers]

Not sure if this should have been posted here or in the Racing forum, but figured I would try here first as the car is a Boxster

At the start of this year I put together (with some help) a dedicated 2001 Boxster S Racing car.



You can see the history and build here.

The season is coming to an end soon here in Finland and I am planning my projects to improve on the car for next season, and want to focus on the engine. One thing that was disappointing was the results of the dyno test that was done for the club at the start of the season this year - which showed my car as low on hp, as you can see here.



I see that many recommend the Softronic flash, and will do this but would like to do as much else as possible before this. And was hoping you all could assist me in selecting the correct upgrades for my engine. I already have a race exhaust, but that is the only upgrade done so far to the engine.

So, if you were building a dedicated racing car what engine upgrades would you suggest?

[mikefocke]

What restrictions does the class of racing you run place on what you can do to the engine? What restrictions does your budget place?

I can point you to a ~450 HP normally aspirated Boxster engine but it isn't stock displacement, it isn't cheap and it isn't on your side of the pond. I only mention it to show you the possibilities at the extreme.

So I think knowing your restrictions might help us suggest an approach.

[Kroggers]

Yes, I have seen the engine for sale - but like you say it is in the wrong location.

At the end of the day I want to be sensible and start with the more simple things and work up. I do not want to go mad and would like to keep the costs realistic. As for power and engine size, there are no restrictions. The only restriction is that the engine must be manufactured (originally) by Porsche.

I know I could replace the engine with a 996 one, but that is outside of my cost. So I am looking for the next quick wins to get a bit more power

[Cajundaddy]

Not many cheap or easy power upgrades for a 2001 Box S. I am also worried about your dyno numbers. Something looks very odd. Might want to get another baseline run before making changes.

If it were my car I'd focus on reliability first, torque second and HP third. You can't win if you don't finish and in road racing torque is king. Hp numbers are for the pub after the event.

1. Underdrive pulley, IMS retrofit, fresh water pump, low temp T-stat, fresh timing chain guides, improved airflow through the radiators, X-51 oil pan, would be 1st on my list. Keep the motor cool and well lubricated.

2. A quality set of headers that emphasize torque.

3. A custom dyno reflash by a Porsche tuning expert where a wide torque curve is optimized.

None of this stuff sounds very sexy or glamorous, but it's just the sort of thing you see going on at Penske or Ganassi in their sports car racing programs.

[Kroggers]

That is all good stuff Cajundaddy, and the type of response I was looking for. I agree 100% that torque must come before hp, and that is more true over here in Finland where most of the tracks have very short straights and lots of bends - torque is king on the tracks over here

Like I said, the car already has a custom racing exhaust installed. Not sure there is much more I can do here, as the regulations state we still have to run with cat's and the max volume is 100dB

I also forgot to mention that the engine was upgraded with the deep oil sump.

The IMS is on my list to do along with a lighter clutch if I can understand what is the best one to get and fit.

What is the Underdrive pulley? Where do I get this from and what do they improve?

Is there any improvement to be gained with better air filter set-up and throttle body?

There is not anyone over here that I know who would be good at a custom dyno tune and flash for me, so I will probably get the SoftTronic flash, but my understanding is that the flash is based on the upgrades you have done - so better to do the upgrades first and then get the flash - or have I misunderstood this one?

[mikefocke]

Consider -

for a tight track, an acusump

visit LN Engineering Nickies The Original and Genuine CNC Billet Aluminum NSC-Plated Cylinders and their cylinders, IMS bearing, thermostat, underdrive etc and for the reasoning behind their use. www.flat6engineering.com is a useful source for reliability insights and what he does to improve the original parts.

visit www.pedrosgarage.com and look at the technotorque and engine mounts. Pedro is a racer too and he can give you advice on the flash...which is really the last thing you do as it needs to match the rest of the things you have done. Some of the best flashes take dozens of attempts with a dyno after each one before you get the right combination of driveability and power!

visit the racing boards and consider a throttle body.

itisn'tfastenough - mikefocke2

[Kroggers]

Thank you for the info Mike.

When you say, consider a throttle body - could you please be a a bit more specific?

[Cajundaddy]

Ok, if you must keep your stock headers and cats, I would leave the intake and throttle body alone also. The stock air box and filter are fine, no gain there. A lightweight flywheel is something to consider but if you do, be sure to have your rotating assembly balanced. Most are pretty far out of balance and can contribute to broken crankshafts and grenading motors.

The underdrive pulley is available from many Boxster racing outlets: RSS, GSR Autosport, Mantis etc. It is a must-have to preserve your PS pump and you get a little gain in TQ to the wheels. With stock intake and headers I don't see much gain from a re-flash. It might add a little throttle response but no improvement in lap times. I would rather have light weight wheels and fresh tires.

[ronster]

Originally Posted by mikefocke

Consider -

for a tight track, an acusump

visit LN Engineering Nickies The Original and Genuine CNC Billet Aluminum NSC-Plated Cylinders and their cylinders, IMS bearing, thermostat, underdrive etc and for the reasoning behind their use. www.flat6engineering.com is a useful source for reliability insights and what he does to improve the original parts.

visit www.pedrosgarage.com and look at the technotorque and engine mounts. Pedro is a racer too and he can give you advice on the flash...which is really the last thing you do as it needs to match the rest of the things you have done. Some of the best flashes take dozens of attempts with a dyno after each one before you get the right combination of driveability and power!

visit the racing boards and consider a throttle body.

itisn'tfastenough - mikefocke2

If you're after torque first ditto on the technotorque, the motor mount and I'd add an EVOM cold air intake.

[Kroggers]

Originally Posted by Cajundaddy

Ok, if you must keep your stock headers and cats, I would leave the intake and throttle body alone also. The stock air box and filter are fine, no gain there. A lightweight flywheel is something to consider but if you do, be sure to have your rotating assembly balanced. Most are pretty far out of balance and can contribute to broken crankshafts and grenading motors.

The underdrive pulley is available from many Boxster racing outlets: RSS, GSR Autosport, Mantis etc. It is a must-have to preserve your PS pump and you get a little gain in TQ to the wheels. With stock intake and headers I don't see much gain from a re-flash. It might add a little throttle response but no improvement in lap times. I would rather have light weight wheels and fresh tires.

I am sorry, I must have given the wrong impressions on the exhaust - my bad

The car has had a custom built racing exhaust from the cats back. but for now the headers and cats are factory.

I do not have to keep the factory headers and cats, but the regulations state that I must run with Porsche or FIA approved cats on the car - the environmental police like to make sure we are good and look after mother nature