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GM TPI & LT1 RESTORATION & THROTTLE BODY BORING SERVICE


NO REFUNDS  90 Day Warranty from date of delivery


Please understand build times are 3 weeks

​SHIPPING

If you wish for your products to be insured for greater than the standard $100 that's included in most shipping services, let us know.   There will be an additional charge.

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  1. Services are for the TPI and LT1 throttle bodies.

  2. The services listed below are performed on your throttle body core.

  3. Shipping is an additional cost ~$18.00 USPS Medium flat rate box to U.S, only. International is at an extra cost.

  4. Please see warranty for information regarding the coverage and overhauling of your throttle body core.

 

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SERVICE #1

TPI BORING SERVICE
        Expanded boring service of your TPI throttle body only.   Please send your TPS with your unit.

 

        We recommend using the modified IAC valve housing on ALL units that have been bored to 52mm.   Meaning, removing the water ports and most of the water ports passages.  When the units are bored they open up in to a few of the screw bosses that the IAC valve housing uses.  We have to seal and modify those.  yes, there are still some threads left, but at times not enough to secure the M4 screws safely.  
       

This is the most comprehensive performance boring service ever offered for the TPI community.  The following is a detailed description of what we do to make your TPI throttle body outperform any other stock modified unit that has been on the market.  We use a Bridgeport milling machine and Criterion boring head with carbide inserts to perform the boring process.
 

Restoration and Throttle Body Boring Service Description:
1.    When your unit arrives we fully inspect it prior to disassembly.  We bag and tag your parts.
2.    Units are completely disassembled and ultrasonically cleaned.
3.    All parts are glass-bead blasted. Threads are cleaned/chased and repaired if necessary.  All openings are cleaned with an appropriate size round stainless brush including vacuum ports.
4.    Throttle shaft is thinned on the bottom as well as opened up on the blade seat surface to accommodate the larger blades.
5.    Shafts are drilled and tapped for a stainless button head Torx-Plus screws
6.    Next step is a multi-step boring process to open up each bore to the exact dimensions specified in your order.  This multi-step boring allows us to provide you with the most accurate bore dimensions and the smoothest bores possible.
7.    Each TB is installed in a custom fixture to resurface the bottom.  We use a 2.5" Kennametal indexable face-mill for this process.  

8.    We now debur and/or chamfer all areas that have been resurfaced or bored.
9.    Next we perform a multi-step reaming process on the throttle shaft bores.  This allows us to achieve an accurate reaming of the shaft bores to fit the double-sealed needle bearings.    
10.  Installation of the sealed bearings is next with a high quality 2-part epoxy.  A 24 hour dry time is required before further handling of the unit is done.
11.   Shaft and spring are now painted/coated with an MRO high-solids chemical resistant paint.

 

Assembly:

1.  Installation of shaft and spring is next.  Custom CNC machined 6061-T6 blades are installed and stainless Torx Plus screws are secured with a permanent LocTite.  These blades have been anodized bright red and laser-etched.  The blades are much thinner than stock.   Stock are .075' thick and ours are .053".

2.  Blade angle and gap is set in each bore to insure the closet possible fit and an approximate idle of 700-725rpm

3.  Installation of your TPS is now performed and voltage is set to to factory specs.

4.  We now install your top plate cover or ours with a new Nitrile Buna-n gasket and stainless socket cap screws

5.  Next, is the installation of your IAC/Water housing with a new .063" Nitrile Buna-n gasket and stainless socket cap screws

6.  Unit is now complete and ready for bench testing and final inspection.

7.  This service comes with our famous 54mm .125" Nitrile Buna-n rubber base flange gasket.

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Price is $300.00 plus shipping of $18.00    

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​​​​SERVICE #2

Same as Service #1, but no boring and no custom cut blades.

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Price is $200.00 plus shipping of $18.00

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SERVICE #3

TBI Bushing Services

     Double Sealed Needle Bearings  $125.00

1.  Remove throttle blades

2.  Remove shaft

3.  Ream throttle shaft bores to accept new bearings.  This is a multi-step process

4.  Install bearings using a 2-part epoxy

5.  Install stainless rod to hold bearings in place as they dry and set.  This is a 24 hour curing process

6.  Install shaft and blades using factory screws 

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© 2016 SPR Performance. Jacksonille, IL 62650

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