A tail of twin cars

[tommy583]

So as you may have seen on this forum that I bought a new car. I started a thread a while back about swapping some of the parts from the old car to the new. Well the swap has been complete for a while and I finally got around to putting the old car back together. Note to self update old thread with pics. Anyways I took the old girl for a test run to make sure everything works.

I always felt that the old car was quicker than the newer one. Same year, same color and after the swaps I have driven each with the same parts. The main difference is the new car has 80k as opposed to 160k. The old car does have the smaller under-drive pulley and the 996 throttle body.

So during the test drive I opened up the old girl a few times. It still feels faster. It doesn't sound as fast because I swapped my modified muffler for the stock one from the new car. Could the larger throttle body and under-drive pulley make that much of a difference? The new car is better and tighter than the old car in every way, but the old one sure seems quicker. The only thing I like better about the old car besides it feels faster is the factory aero kit. I'll miss that about it when I sell it.

[tommy583]

So no-one else has installed the bigger throttle body and under-drive pulley in a 2.5 Boxster? I'm pretty sure someone else did the same mods a few years back. I must be the only one left that still reads or posts on this forum. Well it does seem pretty slow on here lately, so this could be the case.

[Stl-986]

Originally Posted by tommy583

I must be the only one left that still reads or posts on this forum.

Or your the only one that does these kinds of mods on a 2.5

[Starter986]

Originally Posted by Stl-986

Or your the only one that does these kinds of mods on a 2.5

That.

I've read enough posts on this forum and, without considering trying to boost my 2.5, know (from other's experience) that the 2.5 isn't ripe enough. Want ripe... you go the 3+ liter route.

Stl...

[tommy583]

Originally Posted by Stl-986

Or your the only one that does these kinds of mods on a 2.5

I'm not the only one. Maybe the only one in the last few years. I'm not clever enough to come up with this stuff on my own, especially the throttle body.

I'm sure if you have been on this forum long enough you have noticed a big drop off in active participants. In the last few years it seems like the same ten or so members are the only ones that comment on any post. Of the few newer members I have talked to or met in person they commented that this forum isn't very active. It didn't use to be this way. I for one have noticed sometimes there is no new comments on the first post for a day or two. Back in the day there was more new threads started a day then I even bothered to read. Of course by now every question that could possibly be asked already has been multiple times. It must be people are just using the search function like some of the members tell the new people to do instead of just answering the question.

Rant over.

[tommy583]

Originally Posted by Starter986

That.

I've read enough posts on this forum and, without considering trying to boost my 2.5, know (from other's experience) that the 2.5 isn't ripe enough. Want ripe... you go the 3+ liter route.

Stl...

Yes I somewhat agree, but since I did both of these mods around 8 years ago I am the others experience. That being said out of the two 2.5 1998 cars I own, the one with the mods feels quicker. Total cost for both mods is around $200. So if it is nothing more than butt dyno for the money spent I could have done much worse.

[Stl-986]

Sorry, been pulling too many all nighters lately chasing a comet.

In all honesty though, the 2.5 is really not one you see many people do anything to cause there just isn't much you can get out of it. Same can be said for most Porsche engines. If way smarter engineers couldn't get better response with millions to help them out I dont think any of us will get anything more out of it by mixing & matching parts.

I am always skeptical of any of these changes cause 99/100 will say it makes improvements but never have any actual data to back it up. By data I mean something like a dyno run before & after as an example. Without any actual concrete data to back it up it's just placebo feeling/thinking something is better responding/quicker/etc.

[tommy583]

Originally Posted by Stl-986

Sorry, been pulling too many all nighters lately chasing a comet.

In all honesty though, the 2.5 is really not one you see many people do anything to cause there just isn't much you can get out of it. Same can be said for most Porsche engines. If way smarter engineers couldn't get better response with millions to help them out I dont think any of us will get anything more out of it by mixing & matching parts.

I am always skeptical of any of these changes cause 99/100 will say it makes improvements but never have any actual data to back it up. By data I mean something like a dyno run before & after as an example. Without any actual concrete data to back it up it's just placebo feeling/thinking something is better responding/quicker/etc.

Yes I agree with you on the data. That's why i'm clear to state that what i'm talking about is Butt Dyno. I wouldn't waste my time and money on a proper dyno of these two cars. It would cost me much more than the mods did them-self.

The main reason I asked is I remember some of the guys that race spec Boxsters said on here or Rennslist that an easy way to cheat is to put on the 996 throttle body because they look the same from the outside, but will give you more top end and maybe better throttle response than the stock one. The smaller drive pulley will give you the feeling of 5 to 10 HP by freeing up the engine, this is pretty widely accepted. The problem with the smaller pulley is needing to have to shave down the TDC boss on the block.


Either mod would be easy and cheap enough to do to the new car, but the throttle body is more reversible. If I could get 75% of the feeling from just the throttle body then great. But if most of the feeling comes from the pulley then I would just leave it stock.

The only way to really see if there is a difference would be to run both cars on the dyno. Then mod the new car and run that as well. I'm way to lazy and cheap to do that for an engine that we all know will give little to no improvement.

On a more positive note I did purchase a new (used) Quickjack this weekend. I'm pretty happy about that. I borrowed one earlier this summer to do new pads, rotors and paint my calipers. Doing the same job on the old car using jack stands, I can without question say that the Quickjack is the way to go for working on these cars.

[tommy583]

It's actually nice to have a little back and forth on here. My wife doesn't really care to hear about it lol.

[BRAN]

Hey Tommy, just go for it and don't expect anything, you will be surprised, but not blown away.
Here are my performance mods and I love them ALL:

Better throttle response:
- Sprint Booster

Better air intake:
- De-snorkeled
- larger FL side vents
- BMC Performance air filter

Better air flow:
- IPD plenum
- 74mm throttle Body
- IPD boot

Better exhaust flow:
- FL PSE incl. switchable valves

Faster shifting:
Porsche Short shifter

[tommy583]

Originally Posted by BRAN

Hey Tommy, just go for it and don't expect anything, you will be surprised, but not blown away.
Here are my performance mods and I love them ALL:

Better throttle response:
- Sprint Booster

Better air intake:
- De-snorkeled
- larger FL side vents
- BMC Performance air filter

Better air flow:
- IPD plenum
- 74mm throttle Body
- IPD boot

Better exhaust flow:
- FL PSE incl. switchable valves

Faster shifting:
Porsche Short shifter

Old car

Air intake:

De-snorkeled
74 mm throttle body

Exhaust:

Stock

Shifting:

997 shifter.

New car

Air intake:

De-snorkeled

Exhaust:

Boxster S muffler modified.

Shifting:

Bens short shifter.

[78F350]

Neil B from London did a nice series on mods and maintenance on the forum while he had his 986S; Some of the better DIY and informative videos I've seen for the 986. His was an S model, so not quite the same, but same basics.
Here's one of his threads: How much power can you squeeze out of a 986 Boxster S?

Here's his 986 Videos: https://www.youtube.com/playlist?list=PLNKrPMJBU7Wju1zDzxagvESn0QN2JDdkF

As far as:

"... I must be the only one left that still reads or posts on this forum. ..."

I'm guessing that the thread title, 'A Tail of Twin Cars' didn't bring many clicks from people looking to discuss performance mods.