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G-Force Adapter and Flex Plate for Chevy, $600.00 plus shipping.

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I have a (New) G-Force Flex Plate and Adapter for sale. I purchased this for my build and then decided to go a different direction with these particular parts. Note, I did not include any bolts or nuts as these are the way they are sold.
Tire Automotive tire Wheel Motor vehicle Tread
Tire Wheel Automotive tire Motor vehicle Tread

I ended up using a Destroked setup. Here is the back story.

The adapters are simple. The machining from Destroked is "dead on balls accurate." The machining on the Summit version or the G-Force requires checking. When I was looking for an adapter I saw this G-Force adapter on eBay. The woman selling it stated the adapter belonged to her uncle who had passed. She was selling it a part of an estate sale (she stated he was doing a conversion). She was asking $750.00 if memory serves correctly. I bid $600.00 and she took my offer but did add shipping to my bill.

I received the G-Force adapter and mounted it to my 4BT after purchasing the mounting bolts. I went to put my starter on and noticed the bolt holes were not perfectly aligned to the 6.4 starter I purchased (Pennsylvania Performance starter). 1984 Chevy Silverado - 4BT Swap | Page 17 | Cummins 4BT & Diesel Conversions Forums ( I purchased both the mounting and starter bolts from Summit Racing. I wrote a lengthy commentary with pictures of the additional work I needed to accomplish to make those starter bolts work. I ended up drilling a small amount from the lower bolt hole on the adapter to widen it by approximately 1/8 inch.

I ran the engine and the starter was perfect. The starter alignment was good as well and turned the engine over with no binding or any other problem.

I kept reading Johnp77's build and the ongoing issues he had with breaking torque converters. 85 Chevy 4x4 4bt 4l80E | Cummins 4BT & Diesel Conversions Forums ( He called the adapter company who stated they have not ever had any other issues. I personally found this hard to believe as the machining on the CNC doesn't change. Johnp77 went through several torque converters (3 I believe) before he found the problem of the adapter plate not centering the transmission. He was 0.037 off which required the use of offset dowel pins to align the transmission to the adapter. Once that was complete, he has been running great ever since.

I am not saying my adapter is off. I might be dead-on accurate. But since it is not the GOLD Standard (Destroked) it should be checked. I ran into some extra money with the stimulus and was able to afford the Destroked adapter.

The G-Force adapter is good in my opinion. I just didn't have it in me to look at any potential offset. Again, it may be accurate.
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