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| | | | Joined: Dec 2004 Posts: 128 Shop Shark | | Shop Shark Joined: Dec 2004 Posts: 128 | A few people have asked about an adapter to allow existing transmissions that have the SBC bolt pattern to be used with the 4200. So I measured up both the SBC and 4200 bellhousings: [IMG]http://img25.imageshack.us/img25/600/p2150558iw4.jpg[/IMG]SBC on the left, 4200 on the right from a 4L60E to get this adapter plate: [IMG]http://img58.imageshack.us/img58/714/4200tosbcmountplatezw4.jpg[/IMG]this view is looking where the trans will attached. The conventional SBC starter location is on the bottom pass. side and to use a SBC type transmission e.g.(TH350/400) the bellhousing will need a notch/mod tig'ed on to clear the 4200 starter. Also some sort of spacer will be required to take up the 3/8 spacer plate back spacing for the converter/clutch. | | | | | Joined: Aug 2007 Posts: 1,859 Grumpy old guy playing with trucks, cars, and boats | | Grumpy old guy playing with trucks, cars, and boats Joined: Aug 2007 Posts: 1,859 | doesnt kennedy engineering have one already? The ATLAS engines use a modified corporate FWD pattern (or 60 degree motor pattern with one bolt missing). The pattern is similar to the northstar as well with the starter bulge in the wrong location.
Either way, you will need to dial indicate the trans to engine when using an adapter.
If the intention is to swap to manual transmission, then the 5-cyl ATLAS has a FH already. If you are keeping an automatic, the 4L60e FH's are swappable with the 4L60's. Since the pattern is nearly the same as the Northstar/60 degree V6's, couldnt a 700R4 from an early S-10 accomplish the same thing since you have to modify for the new starter location?
Just a few questions.
The problems we face today can not be addressed at the same level of intelligence we were at when we created them - Albert Einstein Or with the same level of $ - Me
| | | | | Joined: Jun 2007 Posts: 17 New Guy | | New Guy Joined: Jun 2007 Posts: 17 | IMO It would make more sense to use the 4200 and the 4200 bell housing on a built 4L60/65/70-E instead of the Turbo 350/400. The 4200 is fuel injected so running the wiring for the transmission is really no etra work. Plus it gives you an overdrive and a really steep first gear. | | | | | Joined: Dec 2004 Posts: 128 Shop Shark | | Shop Shark Joined: Dec 2004 Posts: 128 | The dowel pins are in the same location on the Atlas as on the SBC. Some folks asked since they want to keep their existing transmission.
I agree that the 4L60/70E is a bolt in and that is what is in my truck right now. But there is a limit how much torque even a built 4L70E can take. I wanted to be prepared if I need to put a 4L80E in.
| | | | | Joined: Aug 2007 Posts: 1,859 Grumpy old guy playing with trucks, cars, and boats | | Grumpy old guy playing with trucks, cars, and boats Joined: Aug 2007 Posts: 1,859 | pull the trans appart, throw away the spacer, put in 6 extra discs and clutches, then get a hardened planetary set. You will then break shafts prior to a clutch or the planetary going.
A friend of mine has been doing that for years on 4L60e's in Camaros with superchargers. After that the power train usually takes out the ring and pinion.
The problems we face today can not be addressed at the same level of intelligence we were at when we created them - Albert Einstein Or with the same level of $ - Me
| | | | | Joined: Dec 2004 Posts: 128 Shop Shark | | Shop Shark Joined: Dec 2004 Posts: 128 | My 4L60E has been heavily upgraded to make it a HD 4L70E. Time will tell if its going to put up with the torque input from the built 4200.
Engine status .. I'm waiting for 2 parts to show up, crank trigger wheel, and my intake runners. Otherwise the motor is assembled and ready to fire. | | |
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