Vintage72

Bardman - thank you for sharing. This re-ignites my excitement for the CG race headers . . . that will eventually show up on my door step. I too am only going with headers and a tune - zero other mods as I wanted simple bolt on and off in a few hours from stock to mod to stock as needed. It seems the numbers are significant for this mod!

supercup

Thanks for sharing - I am local to them as well and have CSH coming and may go this route also.

Jimmy-D

What do you think the addition of TB and plenum would add to the CG Sport headers and Tune??. Would it do anything?? Would it add to the top end??. It appears the CG headers and tune did a lot but how much more would the TB and plenum add and where?? That would be a great dyno with that addition and plot it on the graph you posted.

This Thursday I have my Sport headers and valveless exhaust going on. I am going to hold off on the Tune and TB/Plenum for a couple weeks. Deciding if should just do tune and return TB/Plenum or just go big and add them both in 3 weeks.

Any comments/advice welcomed and not trying to high jack thread but maybe some have the same predicament

Bardman

Its difficult to know the benefit before its been done and dyno'd. Again due to the limited dyno charts available I have not seen one which just isolates the TB and plenum. Its worth noting that the results of TB and plenum on a stock car may be different than the results on a car that has headers, and of course tunes all vary as well depending on the parameters that have been changed.

It would be great if you could request the shop doing the work to dyno after each mod to see the effect they each have. Ideally dyno results of your car in the following states:
- Stock
- Sports headers only
- Sports headers and tune
- Sports headers, tune and valveless exhaust
- All the above plus TB/plenum

Obviously its more time consuming to do this (exhaust will get hot on the dyno so you have to wait for it to cool down before swapping it out, etc), but it would be really good information to gather, both for your personal information as well as the community.

BGB Motorsports

Good news folks...6 sets of Sport Manifolds left Germany yesterday. When I get in I will update the thread with the names of the recipients. Thank you again for your patience.

Alan C.

That would leave Jimmy paying for a lot of dyno pulls to satisfy the groups curiosity.

jmartpr

John from BGB posted a dyno chart recently of a stock GT4, a GT4 with CG sport headers + Cup exhaust system and a GT4 with the IPD plenum + TB + COBB ProTune only (no exhaust mods). It was done on a Mustang dyno so numbers are not great but you can see the difference each of the mods make.

Jimmy-D

There is no doubt headers and tune is a great mod. The exhaust I did for more volume and it also drops an additional 25lbs. The TB/Plenum is on the shelf for now but will see down the road.

KingSize.Hamster

Noob question. Isn't 219kW only some 295hp? I thought the conversion between kW to hp is a factor of 1.3-something. Wouldn't this make the dyno runs very low? I thought GT4 dyno figures are much higher at the wheels. Thanks

supercup

I look forward to finishing up suspension upgrades and Cargraphic sport headers and enjoying the car just like that. When John gets the X51 package bulletproof, that seems to me like the best next step.

Patients is important in the early life of modding a car!

usctrojanGT3

Which tune are you going to go with for your race headers?

switchface

Bardman - any chance you can do a side by side pull with a stock GT4 to see what this power gain looks like in action?

I know you said it was louder, but how would you say the tone has changed? I could go for a little more anger, but I don't want to alter the tone, I love it the way it is.

Bardman

His own also as well and they are not that expensive if you are already in the shop. I was very keen to understand what each of the mods were doing to my car which is why I got the three dyno runs. It would be very valuable information for others as well. Of course his call on what he wants to do.

I find that chart hard to read. There are so many overlapping lines, and its not even clear what the three lines mean (the plenum one is clear but the other two not). Its better than nothing, but would prefer a clearer view.

I never really focus that much on the absolute figures from a dyno run, as they vary so much from dyno to dyno. Whats more important are the deltas between runs, showing the difference a mod made when measured on the same dyno.

Bardman

Where I live there are no other GT4s. Occasionally I get back to the 'mainland' with my car, but there are very limited places where you could do this properly without having law enforcement getting involved. Its a possibility but I wont be able to do this any time soon.

With regards to the tone, its slightly more "braaapy" than stock. Not sure how helpful that is, but its difficult to put into words. Ideally I would get some drive bys happening (stock and then mine), but for the reasons mentioned above this will be difficult for me to do.

KingSize.Hamster

I generally agree with that theory. However, 295whp vs 380 at the crank is a huge deficit. Too big to ignore. Almost looks like the dyno is from a GTS.