Finally got my 350 out for the 455 in my 72 cutlass but now trying to put my headers on I find there rubbing on the front cross member where the engine bolts to. any ideas?

 

Maybe change from 350 motor and frame mounts to 455's. If you do, you will need to change both the motor and frame mounts. I did, and have no clearance issues with my headers other than having to ding one next to the starter.

 

Are they headers for a big block? What brand? I have a 455 with 350 mounts in my F-85 with 2" hooker super comps an fit without even having to scratch the headers. JKaz

 

No, no, no. Once again, either set of mounts, when correctly used as a matched set of frame and motor mounts, will place both BBO or SBO crank centerline in EXACTLY the same place relative to the crossmember and frame. It is not physically possible to mount the engine "too low", as the oil pan would be resting on the crossmember.

 

Im using the small block mounts with the 455 and the headers came with the engine when I got it. I still have the 350 headers should they fit better? It sucks I cleaned up the headers that came with my engine and used the header paint on them so it kinda sucks if I cant use them, im not sure on the brand either.

 

I know the 350 headers will bolt up to the 455 heads, don't know that the ports will match never tried it. I did pick up a running 455 one time and it had 350 exhaust manifolds on it. As for fitting the 455 is has a taller deck then the 350 and that would put the exhauts ports a little farther out on each side. What did the 455 come out of? That will hopefully tell you what the headers you have are for.
JKaz

 

My guess is the headers are for a different application than you have. The 350 headers would require as much, if not more, modification as the ones you have on the 455.
Pick up a set for a 455 in a 68-72 and roll with it. Otherwise it's manfolds for you.

As far as 350 manifolds on a 455 I think they used the same ones in single exhause applications as the inlets are the same size.

I actaully had 350 manifolds from a 1975 cutlass on my 455 in a 1980 cutlass into the stock 260 downpipe and cat with a new parts store crossover for a 455 in a 76 delta.
All sitting on the stock 260 engine mounts.

 

The 350 headers will physically bolt to the BBO, but once again, the difference in deck height will likely lead to problems. Common interference points are the steering shaft and the collectors hitting the bottom of the firewall, since the taller deck will move them up relative to being bolted to an SBO.

 

so what are a decent set of headers on a budget?

 

If you buy another set of headers they will probably just interfere someplace elese. I've never heard anyone installing headers without having to "modify" them slightly with a ball peen hammer.

 

Does that mean that there is just a lot of slop in the header manufacturers build process? Why is it that one guy can say they've never had to adjust a thing on a set of headers, and the next guy can use the same part number on the same year/model car and has to beat them up to get them to install.

Not that I can give specific examples of this, but it seems like if kaz442 has put a set of 2" Hookers on his car without a scratch, I'll bet another forum member with the same model as kaz442 has attempted to put the same header on a '70 F-85r and has had to "make some adjustments".

Just sayin'....

 

This is one of the mysteries of header manufacture. You get what you pay for. Spend the money for Kook's and they will fit fine every time. Cheap Chinesium headers won't.

 

Is Chinesium a word? Even a web search on that word is pretty limited!

 

I think it pretty much says it all...

 

I believe Kooks stopped making headers for Olds awhile back and sold the blueprints to Dick Miller who is now making them.

 

i believe Smitty of M&J can help..
i'm on the list for the next set of SBO header!


Smitty
M&J PROFORMANCE
330-875-8096 / 330-495-4582


i believe he is on this forum. i'll PM you his email address.

 

My understanding is that Kooks still makes them but Miller is the exclusive sales agent.

 

I must have gotten lucky then when I put headers on my 70 cutlass that I swapped a 455 into. They fit like a glove, I didn't have to relocate the distribution block to the top of the frame and the starter dropped straight down with no clearance issues. And to top it off I think I only payed $119.00 for them. Granted that was in 1993, but still that was cheap even for then. I think they were Flowtechs if my memory serves me correctly, but don't quote me on that.

 

That is cool! I considered buying headers for my 71 98 a few months ago and decided against it since there were so many posts on our forum about "misaligned" headers. I might buy headers in the future, but if I do I am going to buy the high quality ones so I don't have to worry about them not fitting. If they end up needing "modification" I will just send them back.