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| | | | Joined: Aug 2017 Posts: 68 Shop Shark | | Shop Shark Joined: Aug 2017 Posts: 68 | Hello, I need a quick answer for some serious help. I am going to swap in a few weeks a 366 BBC into my 66 gmc 4000. IT has a 305v6 right now and a sm420. I need to know if I can swap the flywheel and the trans without issues onto my 366. If not what would I need to make this happen?
| | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | The 305 flywheel might have a different bolt pattern. Which bellhousing are you going to use? The 305 might not bolt to the 366, also 420 retainer diameter might be too small for 366 bell housing. Many 366's have Clark 5 speeds, I have one.
Be best to determine all these issues first.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Aug 2017 Posts: 68 Shop Shark | | Shop Shark Joined: Aug 2017 Posts: 68 | I know bell housing if diff now with research im buying a billet retainer ring soacer to use a sm465 bellhousing. Do you know about the flywheel thing? I can just buy a new flywheel thats no issue. | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | What happened to the 366 trans? It is often good to use the trans that goes with the new, larger engine, as wèll as the flywheel, clutch to match up, starter, bellhousing, park brake if attached to trans, starter.
Ed
Last edited by EdPruss; 10/17/2017 5:28 PM.
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Apr 2015 Posts: 113 Shop Shark | | Shop Shark Joined: Apr 2015 Posts: 113 | my 366 is bolted to a sm420. you know where I am so you can come look if that would help.
1959 Chevy 8500 - Spartan 80
366 BBC
| | | | | Joined: Aug 2017 Posts: 68 Shop Shark | | Shop Shark Joined: Aug 2017 Posts: 68 | Sweet man thanks. Ill be in touch!! | | | | | Joined: Nov 1995 Posts: 5,727 24601 | | 24601 Joined: Nov 1995 Posts: 5,727 | Is something wrong with the 305? Just checking -- maybe we can save you a lot of trouble here...
~ John A kid raised on Hotwheels, Matchbox and Tonka cannot be reasonably expected to own only one vehicle as an adult. 1949 Chevrolet 3804In the Legacy Gallery | In the Gallery Forum1973 IH 1310 Dump1963 Kaiser M38A12001 International/AmTran RE3000 "Skoolie"2014 Ford E-350 4x4 (Quigley) | | | | | Joined: Aug 2017 Posts: 68 Shop Shark | | Shop Shark Joined: Aug 2017 Posts: 68 | Rod bearing is shot and its knocking amd i dont really want the v6 | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | That V-6 came in larger versions with the same block, not to discount your interest in the 366.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
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