Bendtsen's Speed Gems evolved from a full service transmission shop into a provider of specialty kits that allow the custom car builder to use a variety of engine and transmission combinations. We engineer and manufacture an array of adapter kits that support pairing engines to modern transmissions so you can use an engine with personality, in addition to getting better power distribution and gas mileage with an overdrive gear. We plan to lead a revolution in the trend of supporting the builder’s ability to select the optimum drivetrain.


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I just wanted to drop you a line and tell you that my tranny swap (C6 to Y-Block) is working great in my '59 Edsel. I drove it on a 1,000 mile trip last week and it's a dream to drive now. We'll be running a tech article about the swap soon. "

Alan, Managing editor/Advertising Manager - Ol' Skool Rodz Magzine

The kit as supplied by Bendtsen's included an aluminum adapter plate, a new high-torque starter, a new flex-plate and a crankshaft extension. The parts are all high quality and as we were to learn later in the operation, they fit together perfectly."

Alan Mayes, Car Kulture DeLuxe

Just wanted to say how amazing your product is! I installed the trans adapter for my 1949 Buick Super 50 convertible with a 248 straight 8 and was extremely happy with the time, engineering, and finesse that was put into creating your transmission adapter. I would HIGHLY recommend this product to anyone interested in a hassle free trans upgrade. Thanks so much for your ingenuity"

Frank Spatacco

It was exactly what we were looking for, and the cool part is that this Y-block adapter will mount an AOD, C4 or C6  to your Y-Block. Of course, the proper flexplate must be used for each of these transmissions, but it is a very versatile adapter plate. We opted for the AOD to Y-block arrangement, and for our $700 we received one very nice machined adapter plate, a new high-torque starter, a craftshaft adapter and a new flexplate. Also included in the kit were all the mounting bolts. The kit isn’t cheap, but it is complete, it works, and all the parts are well machined."

Street Rod Builder

I ordered one of your kits about a year ago and wanted to take a minute to thank you. The kit was way more than I could have hoped for. Everything was top notch. What made me think about you was on a car forum. There were some other guys on there talking about your kits. I wanted to let them know how awesome it is. I know personally after installing the adapter plate (maybe 5 minutes) the transmission was probably the easiest install I ever had. As a matter of fact I took it back out because I thought I was doing something wrong, because it was just too easy. Thanks again."

Justin Moore

I just received my parts that I ordered and wanted to tell you how VERY pleased with the quality I am. Everything fits perfectly. It’s nice to see that some people still take the time to produce quality items. We will be doing more business together, thanks!"

John Treharne

I will say, beyond the fact that I prefer your steel adapter and the use of an OEM flywheel, your customer service is terrific! Thanks for providing me with the info I need to make solid decisions and word of mouth promotion. Thanks again for your time."

Jim Denison

I bought one of your '57-63 nailhead kits to put a turbo 350 behind. Just to let you know, I pulled it all together today. Put it in there and ran it and your kit fits like a glove. You don't find that too often. I built quite a few street rods and some of the units you have to be modify. It worked great, thank you!"

John, Tomah WI

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