I finally got the house back together after 3 years from a tornado and now just ordered stainless exhaust. I wanted stock manifolds and couldn't find anything on the inter web that breathes good enough 2 1/2 I'm guessing so I ordered tri y headers and flow master stainless exhaust.
I say make it the way you want it and ENJOY!!! Sound like some good upgrades. JTS
Thanks I've always liked the sound of flow masters on 5.0 efi
So should be good here too.
Good to hear your back on your feet with getting your house back together. I am sure it could have been a lot worst.
I like the sound of the Flow Master mufflers too! I don't think you will have any regrets going with tri-y's.
Let us know how it sounds when you get it installed. There should be a noticeable gain in HP with the system you are installing.
Good luck!
If that is truly a 1969 Mach 1 it would have at minimum a 351W. To the best of my knowledge there are no Tri-Y headers made to fit a 351W. I am fairly certain the 289-302 Tri-Y headers will not fit a 351W due to the taller deck height. Plus I don't think they would flow well enough for a 351W. Probably kill some upper mid to top end power.
Just my preference, I wouldn't use them on a 302 or 289 either. Tri-Y's are designed to increase low end power. A 289 and 302 has a short stroke so are really not a low end power building motor. For small motors like that with a short stroke, I would build them for mid to upper RPM power. For low end power, start with a larger CID motor with a longer stroke.
If you are concerned about header clearances, look at something like a mid length header from JBA. Some call those JBA headers short and some mid length. However, they are longer than the typical short header that are a bolt on replacement for exhaust manifolds.
I agree, Flowmaster mufflers have a nice sound. Do some research before selecting, many will have a lot of interior resonance noise and get annoying after a while. That's the only reason I went with Borla mufflers. Well, that plus I didn't want my Mach 1 to sound like every Camaro running around my area.
Keep us posted on your progress!
(08-02-2017, 07:16 AM)1969_Mach1 Wrote: [ -> ]If that is truly a 1969 Mach 1 it would have at minimum a 351W. To the best of my knowledge there are no Tri-Y headers made to fit a 351W. I am fairly certain the 289-302 Tri-Y headers will not fit a 351W due to the taller deck height. Plus I don't think they would flow well enough for a 351W. Probably kill some upper mid to top end power.
Just my preference, I wouldn't use them on a 302 or 289 either. Tri-Y's are designed to increase low end power. A 289 and 302 has a short stroke so are really not a low end power building motor. For small motors like that with a short stroke, I would build them for mid to upper RPM power. For low end power, start with a larger CID motor with a longer stroke.
If you are concerned about header clearances, look at something like a mid length header from JBA. Some call those JBA headers short and some mid length. However, they are longer than the typical short header that are a bolt on replacement for exhaust manifolds.
I agree, Flowmaster mufflers have a nice sound. Do some research before selecting, many will have a lot of interior resonance noise and get annoying after a while. That's the only reason I went with Borla mufflers. Well, that plus I didn't want my Mach 1 to sound like every Camaro running around my area.
Good point on correct engine size and valid suggestions on choosing the right header for your application. Personally, I like the tri-y's for the 289's and have no complaints on performance. Plus from a fitment perspective there was has never been a real issue.
I agree, a Tri-Y on a 289 or 302 definitely fits better. More so, if you want to use factory power steering. I just remember reading articles on how they are designed to increase low end power. I'm sure they will help some upper RPM power over a stock exhaust manifold as well. But not as much upper RPM power as full length 4 tube headers.
It sounds like I might have a good opportunity to experiment with the full length 4 tube headers on my Fairlane. I am pretty certain the tri-y's my friend gave me to try out will not work. However, if they do it will save me a few hundred bucks.
I think the Fairlane should have 4 tube full length headers. Don't even consider the Tri-Y's. Something like the Hedman Elite series are a pretty good off the shelf header.