Hello Everyone,

I'm starting a build thread to post some updates, and pictures, of my build. I started about 5 weeks ago in my garage, with my buddy (LQQK on these forums), and now I have my first dyno results (below).

I got most of my parts from Sam @ bydesignauto. He's a great guy to work with, and highly recommended.

Setup -----

- Gt2871r Turbochargers
- Walbro 450l/h Fuel Pump modified into the OEM basket
- 80lb Injectors
- Protomotive Tune
- GT2RS/997.2 Intercoolers
- Aquamist Methanol Injection, running 100% Methanol
- Custom 3" exhaust w/ 100CEL cats (cats are only rated for 300hp, 150 on each side. I used to have two cats on each side for 600hp, but I removed the first set...)


The fueling system is based off of the DIY tim wrote on dropping a walbro pump into the OEM fuel basket, however the gt2 had some surprises. The gt2's basket was completely different than the turbo's setup. The sump that the pump sat in wasn't even the same idea. The pump system also had no jets. This explains how the gt2 gets more stock fueling than the turbo. We fitted the pump using the walbro's fuel sock (you can see it in the basket in the photos below). I can post more photos of the fuel system upon request.

My firsy dyno video is below the pictures. The car made (Uncorrected) 577rwhp, and 605 rwtq @ 1.3bar. I think my exhaust is restricting the top end. I hope to just break 700 at the crank when all my tuning/modding is done. I'm going to gut my cats and see if I can get that restriction away.

Here are some pics:

 

Sexy build pics, just saying

 

Haha. Thanks. I do photography as a hobby

 

Looks like a good build
If you want very small advise , i used to built porsche turbo kits with simple mods !!
If i have your car , i will do these :
Remove the Stock intake airbox and put a intake filters directly into the turbos for much better spool and better IATs ..


Remove the Diveter valves and block the pipe attached to them from the ypipe , and weld fitting in the middle of Ypipe and install tial BOV !!

All if that , can be installed if your tune is mafless so you do not face any problems !!!

Btw .. I knew running filters on the turbos directly is not the best idea , but if u can clean the filters everytime you change the oil , it will be great (also if u live in good weather not rain)


Just my opnion

 

Thanks!

It rains a ton here, so the filter-on-turbo option isn't so viable. I'd like to run it like that, but its tough. I will probably do the intake piping eventually... I'm considering trying some straight pipes, because my exhaust has gotten considerably more quiet with the new turbos. I think its due to the fact that the hot side wheel is a smaller diameter, so the sound gets choked down.

I like the Ypipe idea though.. I think my blow-off valves (even venting to atmosphere) arn't letting the pressure out quickly enough. I still get some compressor surge (Which honestly I like the sound of).

 

Your in the Bellevue area. Ive used CarbCons dyno before as well. They are good guys. Build looks good. Good luck getting the results your looking for.

 

Yessir I am. Thanks!

 

unlike the plentiful 996 tt the gt2 is a car that i believe will appreciate in value as it gets older. these cars are simply amazing. be thoughtful of you mods and think about the reality of returning the car to stock form down the road. too many mods , detract from the beauty of a rare gt2. just my .02 but i do love what you have done!

 

that is impressive man... gl w it.

 

E85 now FTW

 

+1 not doing anything that can't be reversed. Thanks!

 

I'd like to hear someones opinion on my dyno sheets/numbers. Do you think my setup is choking in the top end?

I'm considering doing straight pipes or completely gutting my cats to try and irk my horsepower a little higher. I really want to be able to dyno 700hp at the crank.

 

since theres no industry standard as to crank hp in relation to rwhp i would concentrate more on what the car does at your track of choice rather than a speculative #. crank # range from 10% to 30% depending on the person and what they want to prove. use the dyne as a tool to tune your car for your style of driving and let your time trials , 1/4 slips, course times etc do the talking for you. just my .02

i may be mistaken but isn't your selection of turbos known more for super fast spool great power down low and known to run out of steam up top? not sure theres a turbo out there that gives both fast spool down low and high hp up top

 

The gt28 is a vert fast spooling turbo, yes. I'm happy with the performance, but my end goal was to break 700 crank!

Flat out from 2krpm in 5th I get max boost at 2700rpm. Thats quick.

I totally agree that rhe 60-130, track times, and how the car drives are the most important. However the numbers are loads of fun!!

Thanks

 

to me fun is simply having the ability to sit in a true gt2 porsche and mash the peddle!! better than any dyno on the planet. the look of the car is worth 100 hp any day!

i haven't had the privilege of seeing a gt2 in person yet. from your pics i can see so many subtle differences that turn that car into something special.

intake piping. i was cautious about filters on the turbos myself. best way but a single piece of road debris could cause all manor of debris into the turbo if the filter is knocked off. i was thinking of using the pattern from the turbo oem inlet back towards the trans and slightly upward. a couple braces to support the hard piping and add a filter. helps avoid debris and gets the filter out of the water stream when raining. allows easy access to clean .

tim941nyc also suggested using the small open area BEHIND the i/c and the body. its tight but you could fab a piping and a small filter in there and keep the i/c unaffected by blocking them with a filter. some oval nascar style piping may fit better into that area