lt1badbird

iTrader: (-1)

everything would be built using mandrel bends. not bent in house. thats the norm.

cost would very greatly depending on how nice you want to go aka materials and such. 321 stainless, 304, etc. do you want a nice precision intercooler core with in house made sheetmetal end tanks. single turbo or twins. exhuast layout and material. wastegate/s bov etc etc etc.

to give you an idea we just did a turbo kit on a buick grand national. headers, crossover, flanges, all vbands, EGT's in each runner etc. all in 321 stainless. it was ~1800 for the material alone on the kit. no exhaust, intercooler piping etc. but thats the best of the best material

BlazinT/A

iTrader: (10)

try contacting slowhawk, he is in new england and has built a good amount of turbo cars. He is a great guy to deal with.

fuzzyjk

iTrader: (4)

Assuming small single turbo with truck manifolds middle grade materials is 4k-5K unrealistic?

robbyredneck

iTrader: (1)

i think i would come to your house and do it
and certainly no offense to bad bird.
i have a gtm build manual but i can't remember if it comes with manifolds.
you just buy the u or j bends put the turbo where you want it, get your sharpie out ,fire up the chop saw ,set your mig to kill and get to work. i think you maybe overthinking the difficulty. keep each side as symetrical as you can and use some common sense with basic turbo concepts. i know you want something sweet that you might not see another in your area but if you do build a gtm then you must have some interest in the hands on part of auto building.

jfg455

iTrader: (5)

If you are talking about just the turbo and piping you should be able to do that in 304 SS in a header configuration. A single, quality turbo for this size motor will be anywhere from $800-$1400. A set of 304 headers custom made runs around $1800-$2000. Add in your "down pipe(s)", wastegate flanges, etc and you are right around $4500. Intercooler and piping would be another add but that would depend on how and where you would be able to mount it. If you are building the car as nice as it looks like you are then it is worth doing it right the first time. Just my $.02

fuzzyjk

iTrader: (4)

It does not come with manifolds they are salavged from the donor C5.

As for sizing, I was thinking smaller than 76, I am only looking for 7-9psi. Will a 58 not get me there?

As for an intercooler, it will need to be small.

98TA6.0

iTrader: (42)

that 58 will CHOKE your motor. you could put a nice size hotside and use the 58 but why waste the time and money. have you looked into the TC78? i had the .96 AR turbine on mine and while it choked it up top it worked great in the more driveable RPM range and made big power. you can just turn down the boost if you are only looking for 7ish psi.i think you can also get a 1.15 AR housing which would be better for your car.

robbyredneck

iTrader: (1)

twin 58s would look real nice through the deck and if you kept your manifolds it would reduce your clutter.

jfg455

iTrader: (5)

twin 58's would be asthetically pleasing but is more work IE; double the piping, wastegates etc. If you wanted to run a single then a T4 flanged T70 or T72 .81 - .96 A/R would be perfect. you can run about 8psi on pump gas safely which should net you the 500+ RWHP you are looking for. Turbonetics and Master Power both make nice units (Master power is cheaper, turbonetics has a polished comp housing and is a little better quality). you could keep your manifolds and just run some 304 SS piping to the turbo (2.5" up to the T4 flange, 3" - 3.5" out of the turbo). It would keep it all very simple, look good if the layout is done well, and keep costs down at the same time. Manifolds would retain more heat, be less prone to cracking, and still flow well enough to make up to 700hp (people have done it with 6.0l on here).

As for intercooler(s) you can get creative in its placement as long as you have a good supply of cold air to it. Or you could run a water to air unit that would be more consistant but has more parts to fit into what is a tight area already.

robbyredneck

iTrader: (1)

this^^^

CarsandWomen

iTrader: (19)

do keep in mind the air to water IC also needs a small water resavoir, plastic hoses, and electric pump, and a heat exchanger though. as for turbo, after reading other threads in which several of the experts chimed in, should be between 70 and 78mm to be optimal. be it that its a GTM i would say spend the money and do it right the first time, TC76. physically small, great spool, capable of 750ish hp, great quality, and visually appealing. the TC78 would be great too but based on your power goals just unneeded.

Marcello7x

iTrader: (10)

Honestly after seeing a few pictures of gtm's engine bay it really seems easy. The headers would be the only real challenge. You built it yourself up to now, why not keep going?

rabbit320

iTrader: (11)

what is that red car with the mid engine???

I_Need_Land

iTrader: (12)

factory five racing GTM. pretty bad *** toy you build.

fuzzyjk

iTrader: (4)

Here are a few photos of the engine bay. Also a custom GTM twin turbo built by RPM Hot Rods.............asking price is $119,900 Ouch! I should be closer to 50K done!

fuzzyjk

iTrader: (4)

Could I use the manifolds and bypass the whole header requirment?

I am thinking a single T70 tucked way back under the hatch (where the latch is in the below photo) with custom sheet metal covering the turbo. Sort of like this GTM used the covers to hide the piping. Note this GTM is also running meth on top of twin intercoolers.

BTW this photo will enlarge if clicked on, for some reason the others will not.

smokinz

iTrader: (2)

It would be better for retaining heat and structural integrity to use manifolds. But on the other hand the headers would flow more and wouldn't be that far from the turbo, so they shouldn't loose too much heat!

My opinion would be keep the manifolds and possibly look at porting them out to flow more. I fabed up a rear mount turbo on my camaro over the summer and it was rather easy in my opinion. As far as cost goes, it all depends on material choices as was already noted by other people. My whole build for a rear mount came in right around $2,500 for everything (including beer), But I did get a good package deal on my turbo, wastegate, and bov. So I think your $4-5,000 would get the job done if you do the work and look for package deals on the major components( turbo, bov, etc..) and still have money left over!

fuzzyjk

iTrader: (4)

Turbo...... MP76 .96 $500.00
BOV........HKS $150.00
Wastegate......OBX 41mm or PCP 60mm (either) $200.00
intercooler......Ebay water to air kit $249.00
Manual boost controler........Hallman pro $75.00 or AEM Tru-boost $244.00
Mild steal piping w/6 flanges........... $350.00
Intercooler pipe kit ($100 each x2).......Ebay $200.00
Stock manifolds. $0
Modified stock exhaust $0
Fuel pump................. Walbro 255 $198.75
60Lbs injectors........... Siemens Deka Mototron $340.00
Spark plugs.............$25.00 (which ones should I use)?

Total cost $2350-$2650.............What am I missing?

98TA6.0

iTrader: (42)

edited for ya bro.

Snyper

iTrader: (27)

PM me. Im from CT.