ShakeNBake

I didn't do it, my shop did, and they said the cables were breaking loose of the factory clips, and falling onto headers. After the first time it happened, they went back through and made sure everything was secure, but recommended a heat-shield solution long term.

myBailey07

I was stuck behind a GTR at TWS last time that had no cats. Black smoke and crap billowing out the back of the car. I could barely breathe and that was on the track! Awfully disgusting! I don't understand how anyone can drive a car like that on the street. Dedicated race car different story but on the street it is plain stupid, disgusting and inconsiderate.

If I drive down the road continously throwing trash out my window people would think of me as an inconsiderate *****, yet, driving while throwing crap in the air that I have to breath is "cool" for some or other reason - it's not.

Rant over.

Vintage72

+1

COBB Tuning

Very interesting that anyone with a GT4 saw only 1-2 whp gains with our Stage 1 tuning, I'd be very curious to see the graphs from that car and what fuel was being used. I personally sat in a member's car when he generously allowed us to use it for Stage 2 map development here in Austin and the gains were immediate and repeatable (DynoJet). As for the current Stage 1 dyno graphs on our website, those are from our COBB SoCal location and the Mustang dyno there. However, once this:




And this:





Finish up their break-in mileage, we'll have some stock vs Stage 1 dyno graphs available from our Austin dyno as well. In the meantime, feel free to let your dealer know we'd love to hear from him and discuss what, if anything, may be causing his less than expected results.

Thanks!

~Jared

jmartpr

Hi Jared:


I'll try to get you the graphs and more info. He is one of your dealers down here in Puerto Rico with the shop owner car. Gasoline is 93 octane pump gas. Dyno is a Mustang. I will probably end up doing the AP but just want to see the gains with just exhaust mods now before I later add the IPD plenum and the TB. Could you provide here a bit more info on Stage II?

jmartpr

Diesel GTR? Seriously...if it was black smoke it was probably running too rich, which means unburned gas out the tailpipe. Some people still believe this is a good sign on force induction vehicles. In reality he was making a lot less power and wasting gas.....besides the long term engine problems he will have

Jimmy-D

Jared,

I have my GT4 arriving in 3 weeks. Probably be ready for the tune mid-June. Do you know when you all will have Stage 2 finalized and commercialized?

Dr. G

I just did the Cobb Stage 1 tune on my Spyder and can definitely feel a difference. It's more noticeable when going from the tune back to stock. It doesn't feel like only 1-2 hp of gains.

Now the big question is whether the Spyder is truly 370hp vs the 385hp of the GT4 in stock form. If so, I would expect to feel more of a difference than a Stage 1 GT4 being that the end points are the same. I still question whether there really is a difference in stock power production between the two cars, though.

I was thinking about the GT450 package from Fabspeed but I really like the way the stock exhaust sounds. Is anyone considering headers, plenum, throttle body and tune while retaining the stock exhaust?

Dr. G

The great thing about Cobb is the ability to do a protune dialed in to maximize gains with your particular mods. I would think you would get better results over an off the shelf stage 2 tune. From what I understand it can be done just by analyzing the data stored in the ECU log after your mods are done. I'm sure Jared will correct me if I'm wrong on that.

Bardman

Remember the 1-2HP is peak gains. There can be more significant gains elsewhere in the curve which you would definitely feel even if the peak gains are only 1-2HP.

Jimmy-D

I have bought LT Sport Headers w/cats and that will be my first mod. If I am happy with the exhaust note and volume will go throttle body/plenum/tune. There has been too many people either reporting drone with after market exhaust or recommending not the best upgrade but at least they are being open about it

Bardman

Would be good to identify a list of headers available for the GT4 and relative merits of each.

I am aware of:
- Fabspeed
- FVD
- Cargraphic
- Dundon (WIP they have not released a product yet)

Anyone installed any of the above and has feedback?

Are there any other options?

Dr. G

What brand did you end up choosing for the headers? I'll be running cats as well.

Jimmy-D

You know - I think they all will be good. If you have seen the stock one live or in pictures- boy they could of done a better job.

Dundon has done a bang up job on the GT3 but it looks like they are quite busy and could take some time. Many have installed Fabspeed and have been very happy and have commented right away the sound and mid-range punch was quite noticeable.

Hearing great things with Cargraphic. I was very close to pulling the trigger on them

I went FVD because nobody else had an I figured what the heck(not kidding). But, I have previously bought exhausts from them for my 997.2 Turbo years ago and have always been quite happy and always delivered more than advertised. So, there was a comfort level there and FVD, is no slouch, in the Porsche motor sport world.

d00d

Cargraphic long tube headers without catalysts because of the slip fit collector that takes stress out of the system, and because German manufacture.
Dundon will have a similar design and I expect they will prototype until they exceed the others, although the price may be higher.
I've read that under race conditions a catalyst lasts ~10K miles, so keep that in mind if you track heavily.