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89XR7TD
09-25-2013, 11:39 PM
Is this common after removing them from the head? I've seen some old post stating they have had to ream out a hole or two of the manifold to be able to bolt back up to the head and i'm thinking this is my current problem with the passenger side...

XR7 Dave
09-26-2013, 08:56 AM
Is this common after removing them from the head? I've seen some old post stating they have had to ream out a hole or two of the manifold to be able to bolt back up to the head and i'm thinking this is my current problem with the passenger side...

Yes, that is not uncommon.

archerman0531
09-26-2013, 01:50 PM
It's about that way with any car. They even have a special jig type tool for my Chevy truck with a 350sb because they warped so bad.

WhiteThunder
09-27-2013, 04:53 PM
I had that happen on my '90 SC. The shop were we built the engine had a tool to put between the manifold runners. It moved them so they lined up with the bolt holes correctly. It had a hex shaped barrel with two threaded pieces on each end that could be turned with a wrench. The ends were half circles that went up against the manifold runners.

Eddie
'90 5-speed SC modified
'90 auto SC stock

Mike8675309
09-27-2013, 05:23 PM
I had to heat one up and use a pry bar to get it to fit back on the block on my 90 when I changed the head gaskets with the motor in the car. It's irritating to say the least.

89XR7TD
09-27-2013, 10:24 PM
Definitely sucks, and couldn't happen at a worse time...

Jacob_Royer
09-28-2013, 06:48 AM
Tom I had one side that was really hard to get on so I just drilled all the holes out to the next size bigger so it woukdbt be such a ~~~~ to install them in the car! You can do it with a hand drill but be careful cast likes to grab I recommend using the clutch setting on you're drill because of this !

nmcbchief
09-28-2013, 10:00 PM
I have a spare driver side manifold and a passenger side from an early model.

mywhite89
09-29-2013, 10:27 AM
I had broken bolts in the head that I believe may have been due to this problem. I just drilled the holes larger also and. As Jacob warns, i tried to break my wrists a couple times in the process.

Chris

Jacob_Royer
09-29-2013, 11:07 AM
Just get out you're drill bits and find the one that's a match for
you're holes and go up 1 or 2 sizes it makes life so much easier
also grind more lead on you're manifold bolts makes it a lot easier to
get them started!!

Jacob_Royer
09-29-2013, 11:09 AM
If you use s drill press put the manifold against the post so when it catches it won't kick you're azz

89XR7TD
09-29-2013, 05:10 PM
I'll be replacing the pass side with a late model ported one....I may leave the driver side alone since as I was trying to loosen the nut on the bolt with the oil dipstick tube it was just bending and turning all at once and about to break.

Will that mess things up? Having a better flowing side than the other?

MadMikeyL
09-29-2013, 07:55 PM
It wont mess anything up, but I have a few dipstick tubes if you want one.

89XR7TD
09-30-2013, 06:51 PM
Thanks Mike!!!

See ya after the Shootout man!

capri347
10-02-2013, 06:12 PM
does anyone know if this would fit on the 90 s/c?

http://www.latemodelrestoration.com/item/PAC-703221/2001-04-38L-Mustang-V6-Pace-Setter-Long-Tube-Headers

Ken Seegers
10-03-2013, 08:27 AM
does anyone know if this would fit on the 90 s/c?

http://www.latemodelrestoration.com/item/PAC-703221/2001-04-38L-Mustang-V6-Pace-Setter-Long-Tube-Headers

Not directly...They need to be modified.

Ken

Scott Long
10-03-2013, 09:59 AM
does anyone know if this would fit on the 90 s/c?

http://www.latemodelrestoration.com/item/PAC-703221/2001-04-38L-Mustang-V6-Pace-Setter-Long-Tube-Headers

Might need some re-working around the steering shaft but for that price it might be worth it to buy them and mark them up and then have the adjustment cuts and re-welds done. Still WAY less than a set of KOOKS.

capri347
10-03-2013, 05:01 PM
sorry for jacking a thread but i was think on doing the long tubes you can't beat it for the price IMO

89XR7TD
10-04-2013, 08:27 AM
That does sound like a good plan.....No jacking its cool!!!

Scott Long
10-04-2013, 10:34 AM
i've got a set of mac shorty headers to put on my car, but i'm thinking i might just get these long tubes and make them fit.

Mike8675309
10-04-2013, 01:27 PM
i've got a set of mac shorty headers to put on my car, but i'm thinking i might just get these long tubes and make them fit.

Why? There is no material advantage to long tube headers on these cars until you start making some big horsepower. And in the end the quality of the headers are probably not all that good anyways.

Scott Long
10-04-2013, 01:53 PM
so for a 350-360 rwhp car there would be no benefit switching?

Mike8675309
10-04-2013, 02:29 PM
so for a 350-360 rwhp car there would be no benefit switching?

The main benefit of getting off the stock manifolds is the lack of good cylinder to cylinder balance across all ports. This lack of balance is only made worse and you make more power (i.e. move more air volume). But stock manifolds with ported outlets (open up the down tube outlet to even out the flow) worked perfectly fine to get me near 450rwhp and that was fuel/electricity limited to 5300rpm (had some kinks to work out that I never got back to).

XR7 Dave has a thread where he flow bench tested stock exhaust manifolds as well as shorty and long tube headers. Assuming the long tube headers are designed well and provide good cylinder balance (and that's a big assumption) their improvement will only be seen on the top rpm end of any car and most of our motors stop making power at 5500rpm (my motor was built for 6300rpm).

Could I have made more power easier with better flowing exhaust? perhaps, but I don't know if it would have been a significant amount. My next step was to build some custom 34" primary tube headers but that was to get more even cylinder performance, not to gain any particular performance benefit.

My thoughts on all this are specific to positive displacement motors. NA motors have different needs than ours do.

You already have shorty headers, and assuming the flow is not worse than the stock manifolds then I don't believe you would see enough benefit to justify the cost. Unless you are chasing 1/2 of a tenth at the track and have nothing else you could buy for your car to make it faster, then I would suggest avoiding long tube headers.

capri347
10-04-2013, 05:46 PM
good point but i have plans for my car.. so these long tubes seem more budget friendly even though i may have to make themwork....im thinking long term with these and i am wanting around 350-450hp and hopefully greater torque when i am done with everything i wanna do seems like a long shot but hey i can dream huh?:rolleyes: :D

dthompson
10-04-2013, 06:15 PM
It seems like I remember reading that the long tube headers make tuning more difficult compared to a mid length header. Someone correct me if I have misrepresented the issue.

820
10-04-2013, 08:53 PM
Read daves thread before you go and jack up your car. its all there in black and white. port and polish your stock manifolds, then wrap them in heat wrap if you want. Like mike says a forced induction engine has different need than an na engine.....