I'm putting a 383 into my 67. I have the numbers matching 327, but have pulled it out and stored it. I'm using my original frame brackets and some new red polyurethane motor mounts from summit.

http://www.summitracing.com/parts/PTP-7-504/

The mounts line up, and I've test installed the motor before and was able to put the through bolts through the mount/bracket. The trouble is, a few things make me think the motor is sitting too far back toward the firewall.

1. My HEI in-cap-coil distributor no longer fit between the distributor bore and firewall (it was tight with the 327, but a total no-go with the 383).

2. My throttle linkage binds against the driver's side head

3. The transmission shift tower sits so far to the back of the tunnel opening that it binds on the shifter boot (by about 1/2 inch) and the tranny won't fully sit up into the tunnel.

4. Driver's side header binds on the power steering box. If it were 1/2 inch further forward it would clear.

All that makes me wonder if I've put the frame brackets in on the wrong sides or if the motor mounts are offset somehow from what I had on the 327. The frame brackets have a small lip at the base plate to where they only seemed to logically fit onto the subframe one way. I'm posting some pics to help illustrate:

 

Just guessing but from the pictures it looks like you could switch the driv/pass side frame mounts and turn them upside down and you would have the correct spacing? Again, I am just guessing. Do they have 2 bolts on the bottom as well as the top?

 

Nope, they are a tripod bracket, two bolts on the outside, 1 on the inside. The issue with swapping sides is the little lip that is now hanging off to the left of the frame crossmember in the photos I posted. I tried them (without trying to bolt them down) the other way around but it looked like that lip would prevent the base of the bracket from sitting flush against the frame crossmember. Because of that, I mounted them the other way.

 

I checked with my tranny maker (Kiesler/Tremec TKO 600) and got a rear-of-trans to diff measurement and checked this against my car. The tranny measures out just where it should. Hmm. I guess the motor is in the right place front-to-back.

I guess I'll have to cut a bit of the metal out of the tunnel opening to fit the shift tower in. Kiesler says that some 67s have the tunnel opening a bit further forward. Not sure but the evidence is with them on mine at least.

As for the headers, I guess I could either try to sell them (even with the scratches I put on them putting them in) and try to find another set that will fit (even though Summit said these would fit). Or, I could try one of the following:

1. See if a local speed shop can modify the driver's side header to give more clearance to the number 1, 3, and 5 pipes so they clear the power steering box.

2. Make a custom set of frame brackets that will shift the motor 1/2 inch to the passenger side. Not sure if that type of offset will adversely effect the operation of the driveshaft/diff?

Suggestions?

 

The motor mount attaching point on the block should be in the same position as was on the 327. The one thing that's probably changing your fitment is the urethane mounts replacing the old and possibly compressed rubber mounts. On the top of the frame brackets, are there any dimples, or is it smooth?

 

The brackets are smooth on top. They are the tall/thin variety. Do you think I'd be messing things up if I tried to shift the motor 1/2 inch to the passenger side? I know big block frame brackets are sized differently to do just that, but I'm not sure what else has to change to compensate for the shift (e.g. z-bar changes, crossmember changes).

I'm also considering trying to modify the headers a bit. Not sure if a custom exhaust shop can do that or if it would just trash the header anyway.

 

Given the fact that the tranny-to-diff measurement is right on, I decided not to try and move the motor using special mounts.

I talked with a race/exhaust shop, and they said it isn't possible to modify the headers 'correctly' without spending a ton of $$. They said most guys just ding the headers enough to make them fit. I wasn't willing to ding mine in the 1/2 inch it would take. I've got a set of Doug's Headers d368s on order. They look nearly the same as the Hedman's 66003s I have, but I'm only hoping for a 1/2 inch difference in the 1/3/5 pipes and that is hard to tell from a picture and they don't give offset measurements.

FYI, Summit said they'd take back the Hedmans even though I put some scratches on them getting them in. Wow, we'll see if the refund check actually comes through. :-)

 

Update. The Dougs Headers D368s fit great! They have plenty of clearance at the power steering box. They are quite a bit heavier than the Hedmans and have a flat flange so the entire flange surface is used for sealing.

The welds arent as good as on the Hedmans though. If I ever get time I will pull them off, have them rewelded all the way around the tube, and grind the openings to match my AFR heads. Sometime way down the road I expect.