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3" Down Pipe with a 46mm Wastegate
Product ID: 3.0DPW/46mmGate

Details 

This is a GN1Performance "3 INCH 46mm EXTERNAL WASTEGATE DOWN PIPE " for a 1986 or 1987 Buick Grand National, T Type, Turbo T, or GNX 3.8 liter turbo V6. This 3" Inch External Wastegate Down Pipe is constructed out of 304 stainless steel and comes with a V Band 46mm custom wastegate. All tig welds and is built to clear headers. Please keep in mind that when ordering any external wastegate down pipe a boost controller is need to allow it to function properly and avoid any damage. 

  • Note- This pipe REQUIRES an aftermarket Boost Controller 
  • This item will not work on a lowered vehicle due to contact with the upper control arm.
Price: $485.00

3" Down Pipe with a 46mm Wastegate and Boost controller Combo
Product ID: 3.0DPW/46mmGateCombo

Details 

This is a GN1Performance "3 INCH 46mm EXTERNAL WASTEGATE DOWN PIPE and BOOST CONTROLLER COMBO " for a 1986 or 1987 Buick Grand National, T Type, Turbo T, or GNX 3.8 liter turbo V6. This 3" Inch External Wastegate Down Pipe is constructed out of 304 stainless steel and comes with a 46mm custom wastegate. All tig welds and is built to clear headers. The boost controller comes complete with all the hardware needed to install it..

  • This item will not work on a lowered vehicle due to contact with the upper control arm.
Price: $570.00

3" Down Pipe with a Flat Flange no Wastegate
Product ID: 3.0DPW/FLATFLANGE

Details 

This is a GN1Performance "3 INCH FLAT FLANGE DOWN PIPE WITH " for a 1986 or 1987 Buick Grand National, T Type, Turbo T, or GNX 3.8 liter turbo V6. This 3" Inch Down Pipe with a Flat Flange and no wastegate provision is constructed out of 304 stainless steel. All tig welds and is built to clear headers. Please keep in mind that when ordering any external wastegate down pipe a boost controller is need to allow it to function properly and avoid any damage.
  • Note- This pipe REQUIRES an aftermarket Boost Controller 
  • This item will not work on a lowered vehicle due to contact with the upper control arm.
Would You Like to Add a Boost Controller? Yes (+$99.00)
No
Price: $384.00

3" DownPipe with Internal Wastegate
Product ID: 3.0DPW/InternalWastegate

Details 

This is a GN1Performance "3 INCH INTERNAL WASTEGATE DOWN PIPE " for a 1986 or 1987 Buick Grand National, T Type, Turbo T, or GNX 3.8 liter turbo V6. This 3" Inch Internal Wastegate Downpipe is designed to work with your factory turbo and factory wastegate actuator! This Product is constructed out of 304 stainless steel and is all tig welded, built to clear most headers (Our SE Headers).

Installation is simple, remove your original 2.5" Downpipe and remove the cast iron elbow on the exhaust side of the turbo. Leave the actuator on the turbo and bolt the new pipe on!

A new test pipe or cutout will be necessary to adapt the new Downpipe to your exhaust.

 Made in the USA! 

Would you like to add a Cutout or Test Pipe? Yes a 3" Test Pipe (+$79.00)
Yes a 3" Cutout (+$89.00)
No, not at this time
Price: $489.00

3.5" Down pipe with Flat Flange
Product ID: 3.5DPW/FLATFLANGE

Details 

This is a GN1Performance "3.5 INCH INCH FLAT FLANGE DOWN PIPE" for a 1986 or 1987 Buick Grand National, T Type, Turbo T, or GNX 3.8 liter turbo V6. This is our all new 3.5" Inch Flate Flange Downpipe constructed out of 304 stainless steel. All tig welds and is built to clear headers. 

  • Note- This pipe REQUIRES an aftermarket Boost Controller 
  • This item will not work on a lowered vehicle due to contact with the upper control arm.
Would You Like to Add a Boost Controller? Yes (+$99.00)
No
Price: $474.00

3.5" Down pipe with V-Band flange
Product ID: 3.5DPW/VBAND

Details 

This is a GN1Performance "3.5 INCH V-BAND DOWN PIPE" for a 1986 or 1987 Buick Grand National, T Type, Turbo T, or GNX 3.8 liter turbo V6. This is our all new 3.5" Inch V-Band Flange Downpipe constructed out of 304 stainless steel. All tig welds and is built to clear headers.  

  • Note- This pipe REQUIRES an aftermarket Boost Controller 
  • This item will not work on a lowered vehicle due to contact with the upper control arm.
Would You Like to Add a Boost Controller? Yes (+$99.00)
No
Price: $474.00

3.5" Down Pipe with a V-Band 46mm External Wastegate
Product ID: 3.5DPW/VBANDEXTGATE

Details 

This is a GN1Performance "3.5 INCH EXTERNAL WASTEGATE DOWN PIPE WITH A V-Band 46mm WASTEGATE" for a 1986 or 1987 Buick Grand National, T Type, Turbo T, or GNX 3.8 liter turbo V6.This is our all new 3.5" Inch External wastegate Downpipe constructed out of 304 stainless steel. It comes complete with a brand new V-Band 46mm wastegate, bolts, and gaskets. All tig welds and is built to clear headers. Please keep in mind that when ordering any external wastegate down pipe a boost controller is need to allow it to function properly and avoid any damage.

  • Note- This pipe REQUIRES an aftermarket Boost Controller 
  • This item will not work on a lowered vehicle due to contact with the upper control arm.
Would You Like to Add a Boost Controller? Yes (+$99.00)
No
Price: $684.00

Billet 46mm VBand Wastegate
Product ID: 46mmWastegate

Details 

This is a custom "BILLET 46mm WASTEGATE " for a 1986 or 1987 Buick Grand National, T Type, Turbo T, or GNX 3.8 liter turbo V6. This comes with all of the hardware shown in the pictures. Include a stainless steel flange to work on any application.
Price: $169.00

Billet Blow Off Valve
Product ID: BlowOffValve

Details 

This is a "Billet Aluminum Blow Off Valve". This comes with all of the hardware shown in the pictures. Includes a aluminum flange to weld on your existing tubing and a stiffer spring to work on any application.

*Intercooler pipe not included in this kit 

Price: $189.00

Boost Controller
Product ID: BoostController

Details 

This is a Boost Controller which is good for up to 50psi. It comes complete with all the hardware, fittings, and mounting brackets necessary..
Price: $99.00

Exhaust port picture
Product ID: Exhaustporting

Details 

This is a picture to show how much your exhaust port should be ported when going with an aftermarket external down pipe.
Price: $0.00
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