Twin Turbo Progress or lack of

just wanted to know how big, but was not thinking....Rich

Turbos are Precision 48MM 60Trim. Exh is 57MM with .48 AR housing. Upgraded to ball bearing. As you can see they are not sized to make the kind of power of Corey or Casey. I wanted fast spooling, hopefully with my nonlocking TQ converter, to make in the mid 500 rwhp range. They original had .36 AR housings which I believe was choking off top HP numbers. The original setup in the rear was probably one of the dumbest things I ever did on this car. Hopefully I did it all right this time

Ken
 
good luck

you already know that it looks great, now if you can get it to run half as good as it looks it will be a MONSTER keep up the good work and we will see you at this coming shoot out where you will be kicking some bad a.. See you then....Rich
 
you already know that it looks great, now if you can get it to run half as good as it looks it will be a MONSTER keep up the good work and we will see you at this coming shoot out where you will be kicking some bad a.. See you then....Rich

One way or another I will be at the next shootout. Been to long for me since Ive been there

Ken
 
I don't think I will be in Corey's or your HP range. I would like to shoot for a 10 second time slip. Only time will tell if I put together a working combination to achieve that. Would love to go head to head with Neiberts white SC:D

Ken

Ken,

If you add a full manual trans brake VB, you shouldn't have any problem beating me.

David

PS: 20 lb spring may be a bit much...suggest something closer to 14 psi for pump gas street use, then use a boost controller to go up from there for race gas boost levels.
 
Turbos are Precision 48MM 60Trim. Exh is 57MM with .48 AR housing. Upgraded to ball bearing. As you can see they are not sized to make the kind of power of Corey or Casey. I wanted fast spooling, hopefully with my nonlocking TQ converter, to make in the mid 500 rwhp range. They original had .36 AR housings which I believe was choking off top HP numbers. The original setup in the rear was probably one of the dumbest things I ever did on this car. Hopefully I did it all right this time

Ken

I think the turbos are actually a good size for what you're doing, didn't know they offered those in a ball bearing, that's even better. It should spool well and support your 500rwhp goal.
 
Ken,

If you add a full manual trans brake VB, you shouldn't have any problem beating me.

David

PS: 20 lb spring may be a bit much...suggest something closer to 14 psi for pump gas street use, then use a boost controller to go up from there for race gas boost levels.

I already have the full manual Lentech valve body, man they are pricey. I have yet to use it. I have a wiring diagram for the steering wheel. I am going to try and use the cruse control button for the trans brake. I have a two step system but haven't installed it. Will wait to see how it runs without it. I ran the 20lbs springs on it with the rear mount, I run 100 unlead octane. It is always just a toy and don't plan any long cruses with it, so the added cost of the 100 octane is not to bad. Some day might rethink that.

Ken
 
I already have the full manual Lentech valve body, man they are pricey. I have yet to use it. I have a wiring diagram for the steering wheel. I am going to try and use the cruse control button for the trans brake. I have a two step system but haven't installed it. Will wait to see how it runs without it. I ran the 20lbs springs on it with the rear mount, I run 100 unlead octane. It is always just a toy and don't plan any long cruses with it, so the added cost of the 100 octane is not to bad. Some day might rethink that.

Ken

Since you made a drastic change to the setup, it would be wise to run a lower spring first and make sure you're hitting your desired boost with no creep.
 
Since you made a drastic change to the setup, it would be wise to run a lower spring first and make sure you're hitting your desired boost with no creep.

Explain the creep? I planned to run it on the dyno to run it under controlled conditions and get a before and after comparrision

ken
 
Boost creep occurs when the wastegate cannot dump off enough exhaust to slow the turbine down. This can be caused by too small of gate, poorly located gate, restrictive dump tube, or restrictive down pipe if you run your wg to it. What you'll see on your boost curve is your wg open at your spring but then slowly continue to rise with rpm. My gate is in a bad location, I could put a 4psi spring in and I'll make 18psi creeping to 20 psi by the end of the pull. The wastegate simply can't bypass enough exhaust. It's more noticeable at low desired boost levels when the wg is working really hard.
 
Turbos are Precision 48MM 60Trim. Exh is 57MM with .48 AR housing. Upgraded to ball bearing. As you can see they are not sized to make the kind of power of Corey or Casey. I wanted fast spooling, hopefully with my nonlocking TQ converter, to make in the mid 500 rwhp range. They original had .36 AR housings which I believe was choking off top HP numbers. The original setup in the rear was probably one of the dumbest things I ever did on this car. Hopefully I did it all right this time

Ken

Hey Ken, is your engine 3.8l or 4.2l? I honestly don't think it's going to make a bit of difference in spool up if you switched to 63 ar. Those turbos are going to light off FAST! Might have to throw another one in the mix:D

I run a tial yellow and a 5 psi spring on mine. Grimm speed boost controller but I hate it!
 
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Boost creep occurs when the wastegate cannot dump off enough exhaust to slow the turbine down. This can be caused by too small of gate, poorly located gate, restrictive dump tube, or restrictive down pipe if you run your wg to it. What you'll see on your boost curve is your wg open at your spring but then slowly continue to rise with rpm. My gate is in a bad location, I could put a 4psi spring in and I'll make 18psi creeping to 20 psi by the end of the pull. The wastegate simply can't bypass enough exhaust. It's more noticeable at low desired boost levels when the wg is working really hard.

In the rear location the car never made more than 19PSI. Then I had the waste gates plumbed back into the rear exhaust on the previous setup. It was speculated that backpressure from the mufflers might have been causing the wast gates to opening up bleeding off boost. The new setup has waste gates exhausted to atmosphere so no back pressure there. The exhaust has no restriction after the turbos so spooling should be outrageously fast. Waste gate location is ideal according to ever book on turbo charging I have ever seen. The nice thing about running on the dyno is the ability to monitor it carefully so any spiking of PSI would end the pull. Is that, in your opinion a decent way to go? My waste gates are not the easiest thing to get at since two of everything makes for not a lot of room to work on things. A bad side of twin turbos
 
Hey Ken, is your engine 3.8l or 4.2l? I honestly don't think it's going to make a bit of difference in spool up if you switched to 63 ar. Those turbos are going to light off FAST! Might have to throw another one in the mix:D

I run a tial yellow and a 5 psi spring on mine. Grimm speed boost controller but I hate it!

3.8. If I had to add another it would have to go in the trunk

Ken
 
Hey Ken, is your engine 3.8l or 4.2l? I honestly don't think it's going to make a bit of difference in spool up if you switched to 63 ar. Those turbos are going to light off FAST! Might have to throw another one in the mix:D

I run a tial yellow and a 5 psi spring on mine. Grimm speed boost controller but I hate it!

3.8. If I had to add another it would have to go in the trunk

Ken
 
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I already have the full manual Lentech valve body, man they are pricey. I have yet to use it. I have a wiring diagram for the steering wheel. I am going to try and use the cruse control button for the trans brake. I have a two step system but haven't installed it. Will wait to see how it runs without it. I ran the 20lbs springs on it with the rear mount, I run 100 unlead octane. It is always just a toy and don't plan any long cruses with it, so the added cost of the 100 octane is not to bad. Some day might rethink that.

Ken

Ken,

You will need the 2 step to keep rpm and boost levels down to a manageable level when launching. Having the launch rpm adjustable will also be necessary for adapting to changing weather and track conditions. Suggest wiring it into the trans brake button so the only time it's used is when on the trans brake. I had my trans brake activation button on a cord that was wired to a relay mounted inside the glove compartment. I would hold it with right hand while holding shifter, and drop the cord after releasing the button. No matter how you do it, it's going to take some time getting used to releasing the button when you have the gas pedal on the floor.

David
 
Ken,

You will need the 2 step to keep rpm and boost levels down to a manageable level when launching. Having the launch rpm adjustable will also be necessary for adapting to changing weather and track conditions. Suggest wiring it into the trans brake button so the only time it's used is when on the trans brake. I had my trans brake activation button on a cord that was wired to a relay mounted inside the glove compartment. I would hold it with right hand while holding shifter, and drop the cord after releasing the button. No matter how you do it, it's going to take some time getting used to releasing the button when you have the gas pedal on the floor.

David

I bought a cord setup just like yours. I even wired it up. Havent used it yet. One of our smarter members here suggested using the cruse control button keeping both hands on the wheel. I was starting to wire the two step in but got side tracked trying to just get it up and running. Guess there time in the spring to do that as well. what do you set yours in relation to stall speed of your converter. I have a 3000 stall converter
 
You could keep the old springs in, just make sure you start at low timing and good fuel, and be ready to pull your foot out very fast incase
 
Awesome Ken! I've wondered several times what you were up to the past couple of years - missed seeing you at the Shootout.
 
Awesome Ken! I've wondered several times what you were up to the past couple of years - missed seeing you at the Shootout.

Last year my wife had two operations she was recovering from. This year there was so much going on in the family and traveling that we just couldn't afford another trip. Next year my planning will be better and I will be there where ever they decide to hold it

Ken
 
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