SC 330 compound boost build Twinscrew/T72 turbo

Thanks guys, i successfully bled the system last night but won't test it until today. Hopefully it will solve the problem and get the fan working....I'll post once tested.

The bleeding worked out well. Seems to have solved the problem. 1 issue left

The bleeding worked out well. Seems to have solved the problem. 1 issue left I'm posting here and going to post in the tuning section since this is a specific problem.my car is eating spark plugs, a set a week. I'm slightly rich during normal driving, afr about 14.0 give or take .25 through the rpm's. The issue is the bouncing afr of 17.

My idle bounces between 700 and 950 rpm's. Afr 17 and bouncing higher and lower. My injectors are at 2% operating during idle. I would like to increase my idle to an even 1k rpm's. I believe this would help and give me control.

On the 330 TB there was a screw u could turn to adjust slightly. On the 540 tb there is no screw. How do I adjust the air at idle

Wait, do I have backwards? Higher numbers need more fuel to bring it down....?

Yes you have it backwards.
The easiest way to remember is in the name: air to fuel. In your case 17 air:1 fuel. That's way too lean.

I tried, I failed!!!!! One misfire is all I needed (even though it's because of the plugs) its too risky after the time and energy oh, and money


I need to find a professional with FIC experience in My area.

I am gonna get the exhaust done for the turbo. I need to be able to swap the turbo and muffler back and forth. Not hard..the performance muffler shop is walking distance from me, so that's a plus. I'll drop it off on Monday. I wanted to mount the oil cooler, but I can wait. I anticipate having the compound boost set up in the next 2 weeks.

I'll post pics tomorrow....

ok, getting close to the finish line....i had an exhaust leak at the header that was causing the idle issues (it appears) because it has a steady idle now.

I have sketched 2 different set ups for the rear turbo. attached. One pic feeds straight into the turbo but i would have to craft a exhaust pipe with ah crazy bend since the exhaust side would be facing the center of the body. The other would keep the exhaust side facing the back, but the exhaust tube would be at a 90 degree angle, im thinking this will slow volocity. So im still deciding...

I am going to order 2 resonators, the car is WAY TOO LOUD even at 2k rpms. I am desperate to tone down and quite the car. I researched that the larger the diameter of the resonator, the quieter it will be, so i have my eye on a 4 or 6 inch diameter resonator.hopefully with the turbo also muffling the exhaust it can be tolerable because with these 4.10 gears i stay in high RPM's.

last items to purchase:
oil pump and oil lines
k&n filter RX 4130-1 (slim filter direct bolt to turbo)
Exhaust tips

(euro oil filter housing which isnt needed, but nice to have)

Then its off to the DYNO

I looked back through this thread, it has come along way since my engine in pieces on my garage floor, and time wasted waiting for other people to do what i was able to do with some elbow grease, sweat, and the internet!!!!

Since your filter is going to be under the car in the rear, Id pick up one of those KN water bags that go around it, mainly to keep it from getting to dirty, easy to take bag off and clean it then entire filter, clean all the oil off and reoil

Once you put the turbo on, the car will be much much quieter as it's a muffler on its own.

Originally Posted by Tchleung

Once you put the turbo on, the car will be much much quieter as it's a muffler on its own.

Its not going to quiet it down as much as you might think when its a rear mount. but it will some, just not as much as a front mount.

but then this is going off 2 identical gto's one with a single upfront and one with a single rear, but same exhuast size etc no cats no mufflers. same boost, same turbo etc etc

I agree that the turbo wont do much, i dont think it will quite it more than the muffler. Im thinking that mounting it so the exhaust port is facing sideways and then customizing a "S" pipe t exit the current location would produce the most baffle, but then the concern is limiting the turbo with the s pipe...

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My recommendations is to join the manifolds/headers into a 3-4 inch pipe bring it straight back bending to where the muffler will be removed. Then off the turbo using a 2-2 1/2" max pipe all the way either to your intercooler or charge pipe.

Yea, that's what I'm doing. U can see my crude drawing above. I wanted the exhaust to flow straight into the turbo, but i think the curved exhaust pipe would have limited the turbo. So, im gonna do dual into a single with a 90 degree turn into the turbo. It turns single about 9 inches before the turbo. I'm just trying to work out the exhaust tips. I need the flage that attaches to the exhaust side of the turbo to weld the exhaust pipe to. Working that now.

I have an idea for the charge pipe so I won't have to reduce the size of the intake tube. I don't want to limit my bottom end performance. The idea is to feed the 2.5 in charge pipe into the 3.5 inch intake pipe via a "y" weld. Ill put a boost actuated cut out on the intake side to close once the turbo begans to boost.

This should be interesting....

Originally Posted by diablorojo

Ill put a boost actuated cut out on the intake side to close once the turbo begans to boost.

This should be interesting....

You won't see "boost" from the turbo until after that valve is closed.

The only accurate way to do this is to measure turbine speed, and base the valve closing on that. I'll warn you though....measuring turbine speed is a very expensive proposition....I'm going through this now.

My recommendation is to forget about that valve and run all of your air through the turbo.

Originally Posted by PEI330Ci

You won't see "boost" from the turbo until after that valve is closed.

The only accurate way to do this is to measure turbine speed, and base the valve closing on that. I'll warn you though....measuring turbine speed is a very expensive proposition....I'm going through this now.

My recommendation is to forget about that valve and run all of your air through the turbo.

The point is to not see the turbo boost until after its closed....point being the turbo boost will close it. Pretty simple concept. The valve needs to be closed, otherwise, the boost would escape through the air filter if it remained open.

I don't want to breath through the turbo because the 2.5 in charge pipe would be feeding the 3.5 in MAF, that's too much restriction and air loss for me.

Originally Posted by diablorojo

The point is to not see the turbo boost until after its closed....point being the turbo boost will close it. Pretty simple concept. The valve needs to be closed, otherwise, the boost would escape through the air filter if it remained open.

I don't want to breath through the turbo because the 2.5 in charge pipe would be feeding the 3.5 in MAF, that's too much restriction and air loss for me.

So once the valve closes then you are bypassing the MAF? So you'll have two intake pipes, one on supercharger and one on turbo?
This is going to be a tuning nightmare and I don't think the AEM FIC will do the job. In my opinion a better way would be to run them both together as the mustang guys run their setup but I have very little knowledge on this whole concept. I'm really curious to see the out come.

Here is another quick sketch. Maybe this will help. The ecu should have no additional trouble because its still a simple maf calculation. Now, based on this sketch, where are u saying the issue would be...

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wouldn't it work better if you feed all air through the turbo into the twinscrew? so it will be filter->turbo->MAF->TS

That's how its set up...

Originally Posted by diablorojo

Here is another quick sketch. Maybe this will help. The ecu should have no additional trouble because its still a simple maf calculation. Now, based on this sketch, where are u saying the issue would be...

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Scaling the MAF for one or the other will probably cause issues.