66 HIPO manifold question

[mainemustang]

I bought a hipo exhaust manifold for my 66 vert gt. I was thinking of getting a custom exhaust system at the time of purchase, but now I'm considering magnaflow. Does anyone know how the magnaflow can hook up to the hipo manifold, since they are mostly used with headers or std. exhaust manifold? Also, is there any performance difference between the H pipe and Magnaflows' X pipe? Are there any prefab downpipes/head pipes made to connect to a hipo manifold, or will I have to have them custom made/bent? Since I already bought the hipo exhaust, I don't have the header option anymore....unless I win the lottery. Thanks for any info.

 

[1497]

I don't think you will get a Magnaflow X pipe to fit under the convertible. H pipes are readily available from Mustang parts suppliers to fit the hipo manifolds in 2 and 2.25". Based on my experience with oversize pipe exhaust kits (2.25) and convertible under body clearances, have a custom system made at a shop.

 

[68stang289]

If you google "x pipe vs h pipe" you'll get a ton of results. A lot of people seem to say that the X-pipe will give you better numbers and more power, but don't have the dyno numbers to back that claim up. Personally, I think the X-pipe doesn't sound as good as the H-pipe, but it's completely personal preference. I'm sure there's a ton of videos on youtube as well that are probably running a similar setup as yours. Also keep in mind that the x-pipes are not as readily available as the h-pipes so it may be a little more difficult and expensive to find exactly what you want in an x.

 

[guruatbol]

My 65 had magnaflows and hipos and I didn't like the way it sounded. I went with Try-Ys, (headers from Doug) and went back to new magnaflows and got feel it in the seat better performance.

I can't remember if we went with the H or X pipe, but my muffler shop actually had time tickets on his mopar to prove one over the other.

I just went into the super cold garage since Ed is on the lift right now. It has an H pipe. IIRC we did this instead of the X because he had found on his Mopar that it actually ran faster times with the H than the X. He had the slips to prove it too.

So, do I know for sure? no. But the 67 has an X pipe and Ed is pretty close to the same specs and is faster than the 67. Is that why? Who knows?

I decided that the hipos on Ed we OK, but just not for me. He breathes a whole lot better now without them!

Mel

 

[mainemustang]

Thanks for the advice folks. I'm going to try to have my cake and eat it too. I was able to get a magnaflow 2.5" kit for $420, so I'm going to keep my Hipo manifold and try having an exhaust shop fab a connector pipe between the two. As to the clearance/space issue on verts, I know the magnaflow can fit because I had one installed on my other 66 vert. That one has tri-y headers, but there was still room underneath to fit the 2.5" pipe and X-pipe. Was pleased with the sound of that system, but that engine is a 302gt40 crate by ford racing, so I know it will probably sound a little better and louder than the stock 289. Some mild engine mods in the future may improve it. If I run into problems with this plan, I'll post, so nobody else will get a dufus award. Looking back, I probably should have gone with headers, but was a little too stuck on this idea of keeping it all stock. Especially since I had already put in aftermarket suspension components, aluminum radiator, pertronix distributor, etc. Don't know what I was thinking.......actually, probably wasn't thinking at all.

 

[pjbbx]

hi all

after some (much) debating about HiPos, short or long headers, I removed the long headers on the 66 i bought from Pete (AzPete) a couple of months ago. I had Hipo manifold fitted instead and I must say now that the debate seems like a long time ago...
The irritating rattling noise from the leak has gone and ground clearance is better. Now, it is only better. You have to take into account the room needed for the H-pipe so i was able to gain ground clearance but not a foot. It is better.
In the process I also got rid of the cherry bomb mufflers to revert to the super turbo Dynomax fitted ''originally''. The sound is good and definitely much more street acceptable. In fact i really like that sound when turning on the engine. I just find it too noisy after a long ride...
As for the big question of horse power, i don't know is the answer. I did not drive the long headers for long enough to notice a significant difference when moving to hipo manifold. The car still has a lots of oomph and certainly has enough to get me around the roads of Kentucky at speed. Ok, let's tell you the truth: i did not see the difference...

so that does not answer your question, just my 2 cents added to this endless debate. Let us know about your present dealings with the question...
p.

 

[AzPete]

Good to hear. I still think there is not enough difference on the street....the track would be different trying to get every horsepower out of it.