Garrett G30-770 V Band Turbo On A GN, Details Inside

GNVYUS 1

Well-Known Member
Joined
Dec 15, 2002
Well it's been in the works since 2021 and it's done. I had maxed out the TA49 with my new combo at 520hp and only 19psi so I wanted to make a big change, not just the turbo but the mounting and control of it too.

This isn't for those looking for easy or cheap, it's even more $$ than I thought to do all this and I gave it a big #. If you think $6k, more if a shop does the labor. I'm a GN lifer here so it's fun for me but damn it's a lot of $$ to move into the 2020s gated turbo community.

Turbo = Garrett G30-770 = 58/55 in PTE size
V Band .83 exhaust housing
Poston header modified for wastegate
Turbosmart 50mm wastegate with custom dump tube
Controlled by ECU-GN boost solenoid
GN1 3.5"DP modified using Garrett DP adapter
Custom turbo oil return to stock block location
Water feed fittings off intake and returned to water pump
Custom length oil feedline off oil filter adapter
Coatings by LOKO here in IL

Work done at Blackdog Speed here in Lincolnshire IL by techs Gordon and Jeff.
I think of ways to smoke Gs and they make it happen.
Steve D will tune it up when he's back so he'll have more details soon on what is actually happening vs other turbos we run our those of us rocking the TA49.

The biggest challenge was the turbo oil return. I was going to run the T-40 Turbosmart Oil Pressure Regulator but the oil return for that alone was a mess so I ditched that before spending tons of custom hours on it. Then we realized the turbo oil return in general is too tight to get a wrench on for the fittings so....

We used the Garrett G series Aluminum oil turbo flange, welded a tube onto that and a -12an onto the end and cleared the turbo and v band flange. Then run a 90 degree -12an braided back to the block.

To think the header mod for the wastegate and pulling all the headers for coating was easier.

I'll come back after it's retuned and dynod at the same 19psi and 18 degrees like the TA49 to show what 1990s vs 2020s turbo tech has evolved too.
 

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Cant wait to see what the majic dyno says😉
For that kind of money I hope you really see some kind of gain.
Spending several thousands of dollars and still using a 58mm wheel is puzzling to me.
Jumping up to a 64/67mm wheel for far less money and far less mods would be a no brainer.
 
You're right, the money part is not gonna balance out, this custom stuff is just for those of us who like seeing our ideas come to life on our cars. I could've saved thousands and gone 6266 Gen2 that's for sure. Boring hahaha

The G30-770 is rated in the actual power the turbo can make so its almost like saying a 6266 Gen2 at 800hp. But I'll report back to see how our platform responds with these but it's enough to probably create a 7th cylinder hole on the side of a stock block. 😀

Magic dyno is so I'm not doing 120mph down a side road with the tuner. LOL
But I'm curious how Ta49 @ 19psi to 19psi compares so I'm starting there. Then of course this will allow me to go higher in boost and power so I'll probably need around 25psi to hit 650hp yet spool the same as a TA49 and be a real hand full on the street.

PTC 9.5" with the 17 blade, should be loose and tight enough. I'll run slippage calculation after dyno runs.
 
Wow, that's a very cool and expensive experiment you have going on there.
Waiting to see the results, that's for sure!

Is that a Water to Air intercooler you have there?
I'm a little concerned about the 80# injectors and 485LPH fuel pump having enough for the E85 with this new setup.

I'll bet that car is a BLAST to drive, GOOD LUCK!!
ENJOY!!!

- Jerry
 
I forgot to update my signature, 120s and ECU-GN will handle the flexfuel.

Custom PTE liquid intercooler in stock location with Northern Radiator for minimal pressure loss and killer spool. Had to ditch the alky intercooler, took out my last engines headgaskets due to pump failure (my fault, I revived the car in 2019 and replaced $15k of shit and forgot the $200 pump).
 
I forgot to update my signature, 120s and ECU-GN will handle the flexfuel.

Custom PTE liquid intercooler in stock location with Northern Radiator for minimal pressure loss and killer spool. Had to ditch the alky intercooler, took out my last engines headgaskets due to pump failure (my fault, I revived the car in 2019 and replaced $15k of shit and forgot the $200 pump).
Liquid intercooler has a pump too right?
 
I remember this thread, it must of got lost in the one of 1000 crashes this site has had,
we were debating if a 58 mm turbo can move 75lb/min of air... i would guess not but i would love to see the results,
i also think 19 vs 19 psi you would only see around 15-20 hp over the ta49
 
Liquid is using the Bosch Cobra 002 water pump and I run a fan constantly on the radiator so my water Temps are 90-115 depending on what's going on. It's nice and cold, not a tank with no flow, no radiator or fan like most drag cars do. Smaller radiator fits perfectly in the FMIC location too.

I'll report back with details in probably 2 weeks after the tune and dyno.
 
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Liquid is using the Bosch Cobra 002 water pump and I run a fan constantly on the radiator so my water Temps are 90-115 depending on what's going on. It's nice and cold, not a tank with no flow, no radiator or fan like most drag cars do. Smaller radiator fits perfectly in the FMIC location too.

I'll report back with details in probably 2 weeks after the tune and dyno.
That is a very cool setup you have developed there!
You can't be accused of following the crowd!!!

ENJOY!!!
- Jerry
 
I remember this thread, it must of got lost in the one of 1000 crashes this site has had,
we were debating if a 58 mm turbo can move 75lb/min of air... i would guess not but i would love to see the results,
i also think 19 vs 19 psi you would only see around 15-20 hp over the ta49
Right I remember as well.
 
Oh there's 2 of us now, we're growing in size and debt together. LOL
Damn a G35-1050 is some serious steam and it's a 68/62 in PTE sizing, stock power and spool.

Small update.....
Cars currently seeing 10psi on the 14psi Turbosmart wastegate spring. I'll have to swap in an additional spring since 14psi is their biggest. The boost solenoid is only getting 1psi per 10% duty cycle with this spring. Spool up is great and power at 15psi is pretty impressive. But this will not be fast, going slow tuning and the shop has the wastegate wrench. Hahaha
 
Oh there's 2 of us now, we're growing in size and debt together. LOL
Damn a G35-1050 is some serious steam and it's a 68/62 in PTE sizing, stock power and spool.

Small update.....
Cars currently seeing 10psi on the 14psi Turbosmart wastegate spring. I'll have to swap in an additional spring since 14psi is their biggest. The boost solenoid is only getting 1psi per 10% duty cycle with this spring. Spool up is great and power at 15psi is pretty impressive. But this will not be fast, going slow tuning and the shop has the wastegate wrench. Hahaha
Similar set up on pump and alky made 707hp to the tire at 25-26psi. Mine will be E85 and a bit more compression!
 
I meant "sick power"

There's a video of a 7675 at 34psi vs G35-1050 (68/62) at 32psi and the G35 is 50hp down but the spool up is way way better. It's a new day as those 2 turbos are making the same power so these new Gs insane.
 
I meant "sick power"

There's a video of a 7675 at 34psi vs G35-1050 (68/62) at 32psi and the G35 is 50hp down but the spool up is way way better. It's a new day as those 2 turbos are making the same power so these new Gs insane.
What kind of power is the 7675 vs the 6862 making?
There is no way a 62mm ex wheel can compete with a 75mm ex wheel you still need size not just aero.
I have an old 7675 gts turbo that's done 1000rwhp on a buick v6.
Will a 6862 do that -50hp?
Or am I reading your comparison wrong.
 
I just looked at their website.
68mm compressor is at the end at 100lbsmin.looks like it wants to live in that 80/90+lbmin range for efficiency.
Not a bad wheel but other turbo companies do have 100+lbmin 68mm turbos.
Looking forward to see what their 58mm will do on a buick in this thread.
 

Here's the video, go to 1:25 + 1:50.
1028hp PTE 7675
972hp G35-1050 (68/62)

Not sure you need to listen to them but they comment on how they no longer need nitrous so the cars back to back on the street would be a blow out, the G35-1050 would pull instantly on it if you could hold down the torque.

Look at the 3rd rpm/mph area on the bottom of the dyno graph, the G35-1050 has a huge mountain by then vs the 7675 which has very little by then, could be hundreds of lbs torque difference with a similar top end.

I'll try to get back in here soon, luckily I'm not looking to max out the wheels but I can tell you at 15psi it's hilariously fun with at least 10psi more to come at the end. I'm worried 650hp won't feel as fun after all this and I'll chase the power numbers vs the feeling. LOL
 
The 76 has a 1.12 ex housing
The 68 has the 1.21 ex housing.
They dont give any backpressure data and those motors are different but it does show a spoolup difference for sure on that platform.
Spooling a 76 on our buick stuff with a purpose built combo is very fast seeing boost come in on a 76 below 3500rpm.
Back pressure kills the fun though with the platform and turbine wheel.
The 58 should be fun
 
Got a few hours yesterday to dial things in Saturday.....

Turbosmart Genv 50mm wastegate
It came with the light blue 10psi spring (not dark blue 14psi)
Added smaller yellow 5psi spring
15psi on the gate spring max, 14.5 was pretty normal. That's my 0% duty for pump gas just to be safe.

50% duty on the Bob Bailey boost solenoid netted 21psi, holds really steady in log.
40% duty was 18.5psi so this scaling should be good for 27psi and more than I'll need to reach 650hp.
34% duty should get me around 19psi like the TA49 for the dyno back to back.

It spools like a TA49 but hits way way harder, the 49 only netted 19psi max, this was 21psi easy and plenty left in the tank.
Ta49 = 58/56 (.63 exhaust)
G30-770 = 58/55 (.83 exhaust)

The ball bearing, bigger exhaust housing and newest wheel design IMO make this the sickest street turbo. It's feels almost as snappy as my 600hp, 461ci GTO and if you're cruising and hammer it, forget it, it's a damn NA car.

I did a hammer on the highway and it scared the shit out of me how fast it hit 21psi and felt faster than I've ever been in a GN. I can't imagine what you guys and these 1000hp turbos feel, my God.

MAT was 110 degrees at 21psi and matched similarly to my IC water temp so that was interesting to see on the street. Not super cold but with maybe 1psi of back pressure the turbo will NOT push the comp map like inefficient intercoolers.

I'll find out actual turbo/IC pressure loss once we calibrate the new AEM sensor off the turbo. The Low Dollar sensors weren't cutting it.

I still have a M3 pre-turbo alky nozzle to turn on at the very end of tuning to max out the turbo efficiency.

Pictures below are ..
Poston header with custom wastegate log arm. Turbosmart 50mm internal flange resting on the lip of the v band flange for a tight seal. It's like a smaller internal flange inside the bigger outside v band flange, that things not leaking.

Then 2nd pic is the wastegate on and to see the path from header, pretty straight flow for great control.
 

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