H.O. conversion without headers

[87vicFIVEO]

H.O. conversion without headers....

What do you think??

I recently installed dual exhaust on my vic. (magnaflows and an H pipe)

I hope to put a crate motor in this car some day but for the mean time would I see a significant increase in power if I installed just.....

Intake, Heads, PCM and Injectors

And left my stock exhaust manifolds in place????

Would this be a waste?

[88MercWagon]

H.O. conversion without headers....

What do you think??

I recently installed dual exhaust on my vic. (magnaflows and an H pipe)

I hope to put a crate motor in this car some day but for the mean time would I see a significant increase in power if I installed just.....

Intake, Heads, PCM and Injectors

And left my stock exhaust manifolds in place????

Would this be a waste?

YEs It would be a waste. The stock manifolds are a restriction on even a stock Lo-Po, on an HO, it would be completely pointless. USe at least stock Mustang headers, if not aftermarket pieces.

[Blaze86Vic]

You would notice a nice increase in power with the HO conversion, though not all of it. However when you do install a full free flowing exhaust with some nice headers your are going to see a larger gain that most people do going from mustang headers to aftermarket.

[gadget73]

It'll work. The front part of the exhaust isn't as horribly restrictive as people think it is. Its the part behind the cats, and especially behind the mufflers where its a restriction. You could have your stock exhaust slightly modified to use headers with it though. All it would really take is a larger flare on the end of the pipe. The "ball" on the headers is larger than the ball on the manifold. If the pipe's flare is modified accordingly, then the stock exhaust works fine with a set of headers. The headers are somewhat better than the stock manifolds but its not gobs of power better. If you already have new exhaust and just don't want to spend a bunch of money right now on a whole new system, by all means use the stock stuff.

[87vicFIVEO]

It'll work. The front part of the exhaust isn't as horribly restrictive as people think it is. Its the part behind the cats, and especially behind the mufflers where its a restriction. You could have your stock exhaust slightly modified to use headers with it though. All it would really take is a larger flare on the end of the pipe. The "ball" on the headers is larger than the ball on the manifold. If the pipe's flare is modified accordingly, then the stock exhaust works fine with a set of headers. The headers are somewhat better than the stock manifolds but its not gobs of power better. If you already have new exhaust and just don't want to spend a bunch of money right now on a whole new system, by all means use the stock stuff.

That's just it, I know I can get some e7's and an upper intake pretty cheap. I was thinking I could run it that way for a year and then do headers and a full 2.5 in. exhaust when I get the $$

Can I get long tube headers that will work with my car?

I would like to eliminate the cats all together.

[89LincolnTWNcar]

I converted over to mustang headers and a mustang H-pipe with cats on it pretty easily. Then I took it to a shop for a rear section to the mufflers and a drivers side tailpipe. Mufflers were $50 a piece and the exhaust work I got done at Meineke cost about $165. Paid $100 for the newly re-catted H-pipe. So expect around $350. I have a 2.5" H-pipe, 2.25 midpipes and muffler inlets/outlets, and then 2" dual tail pipes. I really need to up it to 2.5 all the way back.

[Tiggie]

And don't forget one of the most important parts of the HO conversion - the cam.

No long tubes. Mid-lengths are possible, but not really worth the work for an stock HO conversion. It will be happy with 1 5/8in shortys.

[87vicFIVEO]

And don't forget one of the most important parts of the HO conversion - the cam.

No long tubes. Mid-lengths are possible, but not really worth the work for an stock HO conversion. It will be happy with 1 5/8in shortys.

yeah....I didn't list all of the parts, but thanks. So shorty headers...how to I eliminate the cats??? Will the shorty headers bolt to an H pipe with no cats, will I have to have a muffler shop make the pipes??

[Tiggie]

yeah....I didn't list all of the parts, but thanks. So shorty headers...how to I eliminate the cats??? Will the shorty headers bolt to an H pipe with no cats, will I have to have a muffler shop make the pipes??

The Fox-Body Mustang shorties bolt to a Fox-Body H-Pipe. If you are looking to go catless, an "Off-Road" H-Pipe for an '85-'93 5.0L Mustang is what you are looking for to be a direct bolt up. Then you could take that to the muffler shop to hook up the rest of your already new exhaust.

I scored a set of factory HO headers and off-road H-Pipe for $75 last year from a place that specialized in working on late model 'Stangs.

[1987LTDmasta]

it will work, but exhaust is gonna sound like shit.

ask my friend PJ and his '68 Mustang.. GT-40 heads, explorer upper and lower, 75mm TB, MAF and cast-iron manifolds from a 78 granada. how pathetic is that? car sounds like a damn harley choking. but it does run.

[87vicFIVEO]

The Fox-Body Mustang shorties bolt to a Fox-Body H-Pipe. If you are looking to go catless, an "Off-Road" H-Pipe for an '85-'93 5.0L Mustang is what you are looking for to be a direct bolt up. Then you could take that to the muffler shop to hook up the rest of your already new exhaust.

I scored a set of factory HO headers and off-road H-Pipe for $75 last year from a place that specialized in working on late model 'Stangs.

Thanks ben, probably what I will do. But if it's gunna sound like shit maybe I should consider high flow cats. The only reason I wanted no cats was I thought it would be louder in a good way.

[interceptor1985]

no Cats are fun on Vicky we took out a pair and blew out the other ones..lol we have no muffs on her neither so she sounds like a Big bad ford truck/race car....Ever watched the movie CAR'S? She sounds like the "Hudson" I don't think you want to run the stock manifolds with the HO my buddy has a 302 in his 68 mustang with 89 crown Vic manni's and it sounds horrid with the roller cam "HO" he's just saving up for some long tube header's.

[mrltd]

Blah blah...our old lincoln had a mild 302 and all stock exhaust. Still would go over 140... And it'd do it quietly.

A stock HO with cast manifolds isn't that bad at all. Could always port the manifolds...If you were really bored.

[1987cp]

Thanks ben, probably what I will do. But if it's gunna sound like shit maybe I should consider high flow cats. The only reason I wanted no cats was I thought it would be louder in a good way.

hehe... X-pipe, anyone? I've really got to find a way to get a sound clip of the exhaust on the Colony Park so y'all can hear how quiet it is.

I haven't checked for exact measurements, but I think eliminating the cats with the stock exhaust and Mustang headers may be as easy as getting a pair of 45-degree mandrel bends from JCWhitney and a pair of Walker female ball flanges from your local NAPA (can't remember the thread where I posted the part numbers), and cutting pieces of straight piping to fill in between. Pick any diameter you want as long as you're willing to adapt down to 2", then when you're ready to lose the stock exhaust you can have a nice X-pipe welded up and go from there.

Honestly, I'm running off-the-shelf Mustang crossovers just like most everybody else. Check around for the factory headers; mine were around $20 on eBay.

[Mr. Land Yacht]

yea, dont forget the Cam
there is a set of headers that can be made to fit a Panther with some work, but with just an HO conversion, it wouldnt be worth it...as long as you get stock 'stang shorties or some 1 5/8" primary shorties, you're all good!