[pnswann1]

I have a 69 GTO Conv with original 400 and muncie M-21 4-speed. I purchased a set of RA111 manifolds to swap out the original cast iron. I'm having problems with the left side. I could not get the manifold to line up unless I disconnected the Z-BAR linkage. Now after getting it all back together the car drives like the clutch is slipping. The Z-bar linkage is contacting the manifold where the Z-bar connects to the linkage coming off the block. Has anyone experienced this problem? Is there a difference between automatic and manual manifolds? I've tried adjusting the linkage to the fork but nothing works. The car ran fine before the swap. Any suggestions?

[68gtoMN]

Is it possible that your engine mount has failed allowing the engine to sit lower in the cradle? If so, it might have been bad prior to the swap. Just a thought.

[Sirrotica]

Is it possible you have the 64-67 manifolds? They are different and exit in a different place. RM1(early style 64-67), exit more towards the rear and RM2(later style 68-72), exit more towards the front, in this link: http://www.ramairrestoration.com/cat...?cPath=31_2_21

They look similar, but as I found out many years ago when trying to use the 70 manifolds on a 67 chassis they hit the rear of the engine crossmember. My car was an automatic so I didn't have to deal with a cross shaft, although I was going opposite what your attempting I had crossmember interference, where your having cross shaft interference, I hope this helps straighten your problem out.

[pnswann1]

I'll check the engine mounts as suggested. They have less that 500 miles on them but I have been doing burnouts. As for manifolds from 64-67 I purchased these new from Ram Air Restorations and I would hope they sent the correct pair.

[gto4evr]

Originally Posted by Sirrotica

Is it possible you have the 64-67 manifolds? They are different and exit in a different place. RM1(early style 64-67), exit more towards the rear and RM2(later style 68-72), exit more towards the front, in this link: http://www.ramairrestoration.com/cat...?cPath=31_2_21

They look similar, but as I found out many years ago when trying to use the 70 manifolds on a 67 chassis they hit the rear of the engine crossmember. My car was an automatic so I didn't have to deal with a cross shaft, although I was going opposite what your attempting I had crossmember interference, where your having cross shaft interference, I hope this helps straighten your problem out.

I don't believe that to be the case. I've got 67 RA manifolds on my 69 vert 4spd with stock 69 pipes and don't have any fitment issues at all with the pipes or the 4 spd llinkage.

[Sirrotica]

There are 2 different part numbers so they are not the same, and they do exit in different places. Since I don't have both manifolds to compare I'm estimating the difference to be 3/4 to 1 inch difference between the early and late, easily compensated by adjusting the depth the pipe slides into the muffler. It's not 3-4 inch difference. Read R.A.R.E.s website and it tells what chassis they fit.

Copy and pasted from R.A.R.E.s website:

RM1
Fits 64-67 GM a-body with d-port heads. also fits 73-79 GM a-body with d-port heads. 69-85 g-body, 71-79 b-body. Ideal for 2.5" or 3" exhaust system. Ports are CNC'd and interior of castings are detailed...ready to run.

RM2
Fits 68-72 GM a-body with d-port heads. Also fits 70 1/2 - 81 f-body. ***For those using cylinder without end bolt holes (i.e. #7K3, 7M5, etc) we have a fix that doesn't require brackets or addl machining on heads. there is a 40.00 shop fee for this mod to the factory headers. Request in "order comments" when you checkout)

Will connect to 2.25" or 2.5" exhaust system. Ports are CNC'd and interior of castings are detailed...ready to run.

Don't believe me or the R.A.R.E. website, take the late ones and try to put them on a 67 or earlier chassis, the flange will be right into the crossmember. I've done it before and had to notch the crossmember to fit. You can believe what you want, but GM wouldn't have designed another manifold if they would all fit either chassis and R.A.R.E. wouldn't make 2 castings if one size fits all. I was trying to help the OP with the information I know to be true, I didn't say it for sure was his problem. I have never done the reverse mounting early manifolds in a late chassis and I said as much in my first post. I only suggested that early manifolds do have the exit further back than the later ones and that perhaps could be his problem with the crossshaft interference.

[gto4evr]

Originally Posted by Sirrotica

Don't believe me or the R.A.R.E. website, take the late ones and try to put them on a 67 or earlier chassis, the flange will be right into the crossmember. I've done it before and had to notch the crossmember to fit. You can believe what you want, but GM wouldn't have designed another manifold if they would all fit either chassis and R.A.R.E. wouldn't make 2 castings if one size fits all. I was trying to help the OP with the information I know to be true, I didn't say it for sure was his problem. I have never done the reverse mounting early manifolds in a late chassis and I said as much in my first post. I only suggested that early manifolds do have the exit further back than the later ones and that perhaps could be his problem with the crossshaft interference.

Relax there guy, it wasn't a personal attack! Let me adjust my previous statement to: I don't believe that to be the case IN THIS INSTANCE.. I have no problem believing you had a fitment issue going from late to an early chassis, All I said was that I did not have the same problem going from early to late. The one size fits all scenario wouldn't apply because the flanges on the 67 used two 3 bolt set ups and the later ones were a 3 and a 2 as well as the passenger side having a heat riser flap in it on the 67's. There's a side by side picture of the 67 and 69 RA manifolds in the zazzarine book and I don't see any obvious shift in the exhaust exit but I can believe your estimate. That comparison just says the runners were formed a bit differently.

Back to the original issue, I'll go with a weak motor mount as my guess. I've been battling a fan rubbing on the shroud problem that I chased on info that the engine cradle has sagged over time. For the hell of it I changed out the motor mounts even though the old ones looked fine and the motor came up almost a 1/4" so I'd start there.

Later,
Dennis

[pnswann1]

Update: I talked to tech support folks at Ram Air Resto and they suggested I remove about 1/8 metal from the manifold. I went a little further. I removed the swivel bracket and ground metal off both the bracket and the two pins. I ground the pin heads down to almost flat as they are pan head type pins. I also removed approx 1/8 inch of manifold material. Now I have approximately 1/8 inch of clearance. Even after doing this I had to replace my clutch pedal as the lever that attaches the z-bar rod to the pedal broke at the spot welds. Maybe the level bent enough to brake when the swivel was hitting the manifold. Who knows. The good news is everything is back to normal. Thanks to everyone who replied to the post.

[JLHarper]

PNSWANN1,

A friend had the same problem. He worked through it so if you need anyone to talk with PM me and I will hook you up.

Jeff

[rolling money pits]

lemme see if i get this straight....

you have a car that could have come with RA exhaust manifolds from the factory - a 69 GTO.

you buy repop RA manifolds that should fit your car with "no issues".

yet you have to grind off this and that to make those manifolds fit your chassis??

[pnswann1]

yes-69 GTO
yes-repop manifolds
yes--had to grind off metal
yes-- cost too much time and agrivation, not to mention that you have to cut your head pipes and they no longer fit. No swap is ever as easy as it sounds.

The tech at RAM AIR Rest told me the manifolds are not exact originals. Automatic cars don't have this problem.

[JLHarper]

Originally Posted by pnswann1

yes-69 GTO
yes-repop manifolds
yes--had to grind off metal
yes-- cost too much time and agrivation, not to mention that you have to cut your head pipes and they no longer fit. No swap is ever as easy as it sounds.

The tech at RAM AIR Rest told me the manifolds are not exact originals. Automatic cars don't have this problem.

I know one person that did with an automatic, but I think it was one of the early runs. Shift select lever/driver side.

[dieseldan]

Originally Posted by JLHarper

I know one person that did with an automatic, but I think it was one of the early runs. Shift select lever/driver side.

I would say you either have the wrong year/part number manifold or you have the z bar installed incorrectly. the 3 bolt exit flange type are 67 the 2 bold exit flange are 68 and up. There is a diference in the part number and fit. Also there is some poor quality repops out there too. I have not had your problem and have installed these on 67 to 70 400s stick and auto cars. I cant ever remember installing RAIII manifolds while the engine was in the car. if you could attach a pic most on the fourm could id what the problem is. Good luck

[pnswann1]

I was sold three bolt exit flange manifolds for my 69. It's a moot point now. The grinding worked and the car is back together. You can install the manifolds with the engine in the car by removing the mount bolt and raising the engine. Just do one side at a time.

[dieseldan]

glad you got it all together. sometimes the tough ones are the most rewarding.

[JLHarper]

Originally Posted by dieseldan

I would say you either have the wrong year/part number manifold or you have the z bar installed incorrectly. the 3 bolt exit flange type are 67 the 2 bold exit flange are 68 and up. There is a diference in the part number and fit. Also there is some poor quality repops out there too. I have not had your problem and have installed these on 67 to 70 400s stick and auto cars. I cant ever remember installing RAIII manifolds while the engine was in the car. if you could attach a pic most on the fourm could id what the problem is. Good luck

Its not my car and the owner is liftime Pontiac racer restorer who knows these cars blindfolded..... so its not anything other than ...early version had problem...what he was told.

Jeff