Swapping out a 200 cid L6 for a 302 V8.

What parts are required to make the swap. I would like answers with reliable sources. I am finding mixed information on this topic.

The engine mounting brackets are different, what years are compatible. I don't want your typical kit from NPD, I want to know what original brackets will interchange.

I have heard some opinions that the springs need to be changed because the V-8 weighs more, while others say the L6 weight more than the V-8.

I will also be doing a disc brake conversion on this same vehicle and would like to know what parts interchange from other vehicles. I don't want to buy and expensive kit, I'd rather get what I need from the junk yard.

  • The weight of the 302 is about 140lbs heavier than the 200 6-cyl. I don't know which mounts will interchange. Also, what transmission will be used? Is it different than what's in it now? Aug 25, 2015 at 19:28
  • @Paulster2 will be putting an AOD not electronic in. Engine is out of 86 Mustang. You have documentation on the engine weight? Two friends arguing about it. Also are the springs different from a 68 with L6 vs 302? Aug 25, 2015 at 19:32
  • I would assume the 6-cyl springs would be less sprung than the v8 springs, but that is an assumptions of a higher weight in the v8. You are putting the entire drivetrain out of the 86 then? At least I thought it was an AOD back then. Aug 25, 2015 at 20:49
  • Oh, and I have nothing authoritative on the weight ... Aug 25, 2015 at 20:57
  • 1
    @Paulster2 Nope, Transmission is out of something else entirely. Not even sure what yet. Whatever my junk yard guy finds me. Aug 25, 2015 at 21:10

1 Answer 1


I have the following information from a good source (done many swaps himself):

  • He believes the '68 Mustang came stock with the 302, so the front suspension should be just fine.
  • When he did swaps before on the earlier Mustangs, they would drop the v8 in and never think twice about changing the front end stuff.
  • You can get heavier duty suspension/steering parts out of vehicles of the same year, such as the Fairlane ... parts will bolt right up.
  • He thought the '68 should have come with the 9" rear, it'll just be non-posi ... if yours has a 5-lug rear, I would bet you can count on it being a 9" (IMHO)
  • The motor mounts for the v8 on the '68 are one piece. Both sides should be interchangeable. You can pick them up for about $20-ish apiece from the parts store. You have to take the I6 "cradle" out, then the v8 ones will fit down in place of them. These should have a standard bolt pattern for your '86 302 engine.
  • The AOD transmission is about 5" longer than the C3/4 or 3-spd manual. You'll need to either fabricate a new mount for it, or you can buy one online. The drive line will need to either be shortened or different one purchased or acquired
  • He says he the 302 would be less than 60lbs difference between it and the 200 I6

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .