964 factory cup chip

i recently purchased a chip for my 90 C4 that is suposed to be a factory "cup car" chip. The number printed on it is "1964355189". Does anyone know if this is truley a factory cup chip. Also what performance gains should I expect? I already have a cold air intake and primary pipe bypass that I'm very happy with and plan a throttle bodie upgrade. Thanks as always for your help, CB!

Sorry I cant answer your question, but I thought I might ask you one if it's ok. I just traded my 88 carrera for a 90 C2 and wondered if you could give me some feedback on the mods you have done on your C4. How does it sound with the primary bypass? So far I only know of the Dansk one at about $350, it seems a bit steep. Can I get a mild steel one cheaper? Does the car feel much quicker with the bypass and cold air intake, thanks .

The bypass pipe adds a very nice sound and added a bit of pep too. The cold air intake made the car a bit louder as well but not to the point of being unusual or obnoxious. Both theese items were great advances on the car the two combined you can actualy feel as far as gains go. I dont have figures but it was worth the dough. I used a stainless bypass pipe on my car and the quality was top notch. Good luck CB!

I have a secondary bypass pipe that I have for sale.

It really doesn't matter which one you bypass as long as you do one of them and drill holes in your airbox.

Tom Sharpes
team5150@aol.com

Cheers CB,
Tom, i have heard that the secondary bypass does not sound as good as just the primary, is this true?. Also,email me how much you want for the secondary bypass as I may consider buying it (davmanku@ev1.net)
Thanks.

The primary bypass does sound the best of the two. Also note this is what Porsche did on the Cup cars from the factory. Also it is balanced with regards to weight reduction for what its worth. Regard CB!