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64 cutlass convertible I bought about 4 months ago. First items up are exhaust, power disc brakes conversion and power steering conversion (exhaust here I will post brakes and steering later in the appropriate threads)
455 with 3 speed swapped by the previous owner. The passenger side exhaust has a "Y off" that goes nowhere and has been bent and folded over to try and eliminate it producing an exhaust leak. My long term goal for her in a cruiser but, obviously ha ha, still want some nice muscle car punch when the time is right! Below are some manifolds/headers I'm considering. Seeing that the Bigblock 400-455 was never in a 64 it is a bit of a guessing game on what will fit. I trying to avoid expensive "Just buy it and see if it will fit" mistakes!...
I am looking for advise on best (easy) fitment along with any suggestions from years of experienced Olds Guys like... can the motor mounts be shimmed up a hair or moved forward (moves into driveshaft issues) for better clearances? Is that worth it or dumb??? Etc... . Mild Cam and intake is also in the future but for now its exhaust and brakes.
Choice 1 - ARH A body OBBA-64178300HR Oldsmobile A-body Big Block 1964-1977 Headers (these are my first choice if they fit but $1500 has me making other considerations) Are they worth the $$$?
Choice 2 - Not as fun but probably the sensible choice at $421.99 : Part Number: OPG-C240268 RESTOPARTS Supplied C240268 - RESTOPARTS Manufactured Exhaust Manifolds
Choice 3 - Thornton 400/455 Big Block Oldsmobile Headers at $600 they seem to be the winner but fitment in my 64 may be the issue
Please also suggest any others that may be a good option from any of your own past endeavors.
Thanks
Rob
I can only wonder how much difference in performance you see between long tube headers. I purchased a set of stainless steel headers for my 455 on Ebay for about $150. The quality was really good, heavy gauge, nice welds, nice bends, fit like a glove. What can they possibly do for another $1350? Has anyone ever done testing? I know shimming the motor up a 1/4" works okay with no issues. What will fit a 64 is a good question, probably someone can tell you.
Steve
I have a set of ARH headers waiting to go in my F-85. They look gorgeous.
Ive heard the fitment is perfect...but have not installed them yet.
All my other '65's have stock exhaust.
-peter
Big block Olds in a '64 Cutlass is about the same as big block Olds in a '65 Cutlass 442. I think the only difference may be the radiator. There are other members on here that have done this swap and may pitch in.
I can only wonder how much difference in performance you see between long tube headers. I purchased a set of stainless steel headers for my 455 on Ebay for about $150. The quality was really good, heavy gauge, nice welds, nice bends, fit like a glove. What can they possibly do for another $1350? Has anyone ever done testing? I know shimming the motor up a 1/4" works okay with no issues. What will fit a 64 is a good question, probably someone can tell you.
Steve
I'd be very curious what material those headers are actually made from. Most people think 'stainless steel' is one particular material grade. In reality, there are many different grades of steels which fall under the common 'stainless' umbrella. Those ARH headers are made from 304. This is an austenitic grade and will only corrode under extremely adverse conditions. These cars will never see those conditions. The more common (and less expensive) automotive exhaust 'stainless' is 409. This is a ferritic grade and is less corrosion resistant than 304 but still pretty good. Most OE exhaust systems these days utilize 409.
At $150, you wouldn't be able to buy the raw 304 material for these headers. I have to think these are made from a material that may fall somewhere far below a ferritic grade and can still, technically, be referred to as 'stainless'. Depending on how much you drive the car, these could be satisfactory for you. I'd definitely keep an eye out for corrosion and stress cracks, particularly at welded joints.
I have a set of ARH headers waiting to go in my F-85. They look gorgeous.
Ive heard the fitment is perfect...but have not installed them yet.
All my other '65's have stock exhaust.
-peter
Those are pretty and definitely my first choice! Just need to tear the Band-Aid off and do it. I'm just looking for some more justification that the quality is worth the money! I'm sure they are I just need to be told they are a few more times lol
I can only wonder how much difference in performance you see between long tube headers. I purchased a set of stainless steel headers for my 455 on Ebay for about $150. The quality was really good, heavy gauge, nice welds, nice bends, fit like a glove. What can they possibly do for another $1350? Has anyone ever done testing? I know shimming the motor up a 1/4" works okay with no issues. What will fit a 64 is a good question, probably someone can tell you.
Steve
150 bucks is almost worth it even if they only last a year it will give me a good education on the geometry if gotta squeeze them in there and I won't feel so bad I have to do a little bending and pushing on them
I can only wonder how much difference in performance you see between long tube headers. I purchased a set of stainless steel headers for my 455 on Ebay for about $150. The quality was really good, heavy gauge, nice welds, nice bends, fit like a glove. What can they possibly do for another $1350? Has anyone ever done testing? I know shimming the motor up a 1/4" works okay with no issues. What will fit a 64 is a good question, probably someone can tell you.
Steve
do you have a part number or a seller I can look up on eBay and do a little research?
I believe the quality IS there...but the owner himself has a '64 and supposedly made the jigs off of his own car.
I believe the fitment is also what you're paying for.
Oldsmobiles and headers are always painful stories. Most have to be dented and dinged up a bit to not interfere with the steering shaft, the control arm or both.
I have a set of ARH headers waiting to go in my F-85. They look gorgeous.
Ive heard the fitment is perfect...but have not installed them yet.
All my other '65's have stock exhaust.
-peter
Why don't you bring them over and we can test fit them and let me borrow them until you're ready!! Haha!!
The Ebay headers claim to be 304 ss. This is the item number https://www.ebay.com/itm/382447780124. All I can say is they fit without having to dent them or make any other changes. I was a sheet metal worker and worked with metal and in my opinion they looked really good. Heavy duty flange, nice welds, good gasket. On the PS side one tube blocks the bolt hole and you must put a stud in. I raised the motor and slid them in from below.
The Ebay headers claim to be 304 ss. This is the item number https://www.ebay.com/itm/382447780124. All I can say is they fit without having to dent them or make any other changes. I was a sheet metal worker and worked with metal and in my opinion they looked really good. Heavy duty flange, nice welds, good gasket. On the PS side one tube blocks the bolt hole and you must put a stud in. I raised the motor and slid them in from below.
Steve
thanks for the link I greatly appreciate it I'll probably give them a shot it is definitely way better than what's in there now I'll post pictures of it later it'll make y'all giggle
The Ebay headers claim to be 304 ss. This is the item number https://www.ebay.com/itm/382447780124. All I can say is they fit without having to dent them or make any other changes. I was a sheet metal worker and worked with metal and in my opinion they looked really good. Heavy duty flange, nice welds, good gasket. On the PS side one tube blocks the bolt hole and you must put a stud in. I raised the motor and slid them in from below.
Steve
I ordered the cheap eBay set I will take pics and post progress and see how they unfold
So these arrived today ! I just pulled them out of the box and gave them a quick once-over. They look good so far! we are headed out camping this weekend hopefully we'll have them installed next week I will let you know how that goes
Last edited by Rob64cutlass; February 18th, 2022 at 08:53 PM.
I think it was the bolt between cyls 6 and 8 that I needed to put a short stud. Some people put all studs in as it may make it easier to get it in place. I was difficult to get the nut on but I got it. I stuffed a rag in under the spot so I didn't keep dropping the nut. I had a little open end wrench that came with Ikea stuff or somewhere else and filed it to the correct size so it could hold the nut in and be bent to an angle. I think in the end a angled set of needle nose pliers worked. On the DS between 5 and 7 I took a drill bit and elongated the hole so I could get the bolt in. The bolts that came with mine were nice but the wrong size. I changed the motor mounts while I was at it.
Good luck,
Steve
I think it was the bolt between cyls 6 and 8 that I needed to put a short stud. Some people put all studs in as it may make it easier to get it in place. I was difficult to get the nut on but I got it. I stuffed a rag in under the spot so I didn't keep dropping the nut. I had a little open end wrench that came with Ikea stuff or somewhere else and filed it to the correct size so it could hold the nut in and be bent to an angle. I think in the end a angled set of needle nose pliers worked. On the DS between 5 and 7 I took a drill bit and elongated the hole so I could get the bolt in. The bolts that came with mine were nice but the wrong size. I changed the motor mounts while I was at it.
Good luck,
Steve
Awesome! Thanks for the heads up on the troble issues it will definatly help me avoid some headaches!
February 15th, 2022, 05:33 AM
