I have bone stock low miles 2004 c4s. Runs great, and I’m about to do something either awesome or stupid. But wanted to share my experience start to finish.

im going to have the performance package( headers, sport cats, xpipe, mufflers, intake, tune)
plus the IPD plenum with the larger throttle body.

lots of umm, opinions out there regarding this stuff, but I am a car nut and I am crazy as we all are and can’t just drive it without farting around with it. Anywho. When you order from the factory it takes about 5 weeks for them to make the system. I live close enough to the factory that I am going to have them install as well. This could either be a good thing or a dumb thing. But hey. Life is an adventure.

Some thoughts leading up to this. Bore scoring. I by all indirect signs have a healthy engine. Haven’t done a bore scope. does the hive think this may exacerbate the potential issue? Should I install the low temp thermostat? It’s a summer, good weather kind of driver only. Try to avoid too many local quick stop and go trips if u can.

couple of weeks til the build is complete and I can have it installed. Thought some conversation on here leading up to it would build suspense or talk me out of it altogether.
If I take the plunge then I can also provide some real world impressions from the perspective of a car dude who is not a mechanic/engineer/know it all.

 

Hey man, good luck with it. Fabspeed offered before and after dynos. Please take them up on it and let us know your improvement. You only live once, might as well do it with a complete exhaust package including software and intake improvements.

 

Subscribed!

Really interested in your results!

 

This is an incredible opportunity for fabspeed selling all of us the package by showing the before and after dyno! Joe Fab should take advantage of this soft pitch.

 

Do it do it do it

 

That is steep. Id pass and put the 8k after tax towards a rebuild with bigger bore.

 

Cool project. Agreed with others, if documented well, this could help solidify arguments before & after. Please get the bores scoped before any work. You should have this as a starting point. I don't think anything you are going to do would make scoring any more likely, but it might change your decision on when to add all the goodies. My current belief is that the best performance after changing how the engine breathes is the tune. You won't realize optimal performance unless the computer understands the change in air flow and can use it. We talk about the computer adapting to our driving or the current engine conditions, but I don't know how far that adapting goes when you change the inputs and outputs by so much. It really needs an individual tune. Good luck! it will be fun watching! Post early and often!

 

Definitely skip the plenum, it does NOTHING

 

What we should do is take bets on how much improvement actually is realized for $8,000. My bet is 2 hp for every $1,000 or 16hp total.

 

A rebuild with a bigger bore sounds even steeper. A “ you may as well “ argument. Every project has its limits and its goals. Don’t want a new engine. Just breathe a little more life into the one I have. Bolt on bolt off. Maintain the integrity of factory build. It’s only done 29,000 miles. I’d tear down and rebuild only after it’s been ridden hard put away wet.

 

Even if you did this you'd still want to at least change the exhaust to something else. My car has a 3.4 to 3.6 with bone stock exhaust and the sound is pretty sad to say the least. Probably the quietest/worst sounding exhaust of any car I have ever owned and I think M96s have the potential to sound amazing. I will never understand why Porsche opted for the mufflers they did. I haven't decided what route I want to go yet though, so it's stock exhaust for me for now.

To the op, I say go for it and document the results if you can. I will also throw out that Soul has been getting a lot of love lately and might be worth a look if you haven't checked them out yet.

Edit: I see you are in South Jersey, definitely see if you can't take Fabspeed up on their offer to Dyno test the before/after. I can't remember the name of the thread that that discussion was in, but it was started by ZBomb.

 

2 recent dyno tests on ‘99 3.4s prove that the IPD plenum does work.
It increases the hp and torque throughout the rev range.
But I haven’t seen any good ( same day/conditions/dyno) tests on the 3.6.

 

Tests using the 3.6 don't show any improvement using oem headers. I will eventually test the fvd m&m headers by adding then to my 200 cell cats and sport exhaust which fvd claims can extract some performance from the ipd/tb. But not until next year.

But it will be very interesting to see the aggregate improvement in power the OP gets with the fabspeed kit since it includes everything. Doubt they will be willing to do a dyno part by part. But you never know.

 

If it’s just the sound that bothers you do the Fister or Gundo hack and save $7500.00… If you really need to dump the cash go for it - just don’t expect some kind of magical performance boost… ain’t gonna happen

 

I'm curious to see what you make, I'd suggest having Fabspeed do the dyno comparison they've been talking about for some time. Justin has a very similar set up btw.