dbxm ffi

[empera]

is it reversed?

 

[X-man]

Sean I'm sure it will probably be fine. If you hook your boost gauge up to the manifold though (perhaprs you already do) you will see that there definantly is nearly constant pressure in there for as long as you hold the throttle open, that's the idea behind having such a large volume in the intake, so that it can easily fill the open cylinder without much pressure drop. In any case you still haven't eliminted a fatigue failure, over many cycles the aluminum will be more and more likely to crack. If you used thick enough material and did a good job welding then it will work, I just wanted to give some constructive input from experience on how the design could be improved if needed, or for others following along.

You are absolutely correct about the constant pressure which is why I stated that you are never building and storing pressure for long periods of time. I should have stated high pressure though and I do run my boost gauge on my manifold. I ran a p trim with a .68 and .81 a/r on a T4 flanged turbine so I was only under constant high psi from 4600 or 4800 to 6700 rpm and positive psi from 3500 rpm to redline. The manifolds are built out of the same basic thickness material as the runners are. I use 5057 rod to weld them to the cast piece and I think the aluminum is 4043 or 5057 also. Most of the time I ran a street boost level of 19 psi and have made about 10 dyno runs ( 1 @ 19 psi and 9 @ 29psi) plus about 5 runs down the track and so far so good. This is one reason I don't build and sell manifolds like Ron or Seth does. I like to test everything I build and I punish my car as far as it is either on the dyno or the track. I don't have the time to build manifolds for sale and Ron does a beautiful job on the ones he does, so the community definitely has an outlet for top quality intakes. It's always interesting when you build stuff for a car to try to figure all the forces that will work on a specific part. I have built commercial trucks for the last fifteen years and welded many frames together and dump truck beds on chassis so I know exactly where you are coming from on concerns of stress and fatigue. I am always looking for way to improve on designs so I am open to suggestions, advice, or critique good or bad and I appreciate you voicing your concerns because I sure don't want Dave having any issues. I build caps and put 60 psi of shop air in the manifolds and leave them for 5 to 10 minutes, but this of course does not test stress under operating temps.

Empera the stock alternator tensioner is used it is moved to the stud at the bottom that used to hold an a/c bracket.
Sean






You can see the stock tensioner in some of the pics.

 

[dbsupra90]

yeah what sean said

but really, it makes things interesting when you design and build one off pieces.
i believe the design and flow will be good. altho this is not my daily driver, it will for sure be put thru some punishment.
perhaps it might need some tweaking or it may be tougher than woodpecker lips. it took edison 2,000 tries to make the lightbulb. he didnt fail, he learned 1,999 ways how not to make one.
i appreciated all you guy's input.

 

[supra90turbo]

supra90- no it hasnt been flow tested. the girl i know that can get her mouth around something that big is out of town at the moment. altho, it is a similar design to sean's manifold and has worked very well.

LMAO! Wave a $5 bill around, she'll be there pretty quick i bet...

If you were to make more to sell, guys, how much would you charge?

-kurt

 

[dbsupra90]

LMAO! Wave a $5 bill around, she'll be there pretty quick i bet...

If you were to make more to sell, guys, how much would you charge?

-kurt

i dont build at all. i merely came up w/ the design for mine.
seriously doubt sean will build any to sell. he likes to abuse them before they are sent out and just doesn't have the time or interest in doing so. he built mine as a favor since we are good friends.

 

[NJsupraA70]

:yumyum:

Awesome work Dave.

 

[empera]

so wait, u wont be using CSI, EGR, ISC?

 

[dbsupra90]

so wait, u wont be using CSI, EGR, ISC?

correct.

there will be ~4 vac ports on the manifold, which will be on the bottom for a clean/stealth look. thats all that is gonna be on there.

thanks steve!

 

[empera]

wat other mods do u have?
im gonna hafta get rid of my CSI, EGR, and ISC also...my design is very similar to yours.

 

[dbsupra90]

wat other mods do u have?
im gonna hafta get rid of my CSI, EGR, and ISC also...my design is very similar to yours.

egr has been gone. csi i didnt bother with b/c i live in a warm state, not driven in the winter.
isc is gone b/c im running speed density via maftpro.

any could have been incorporated into the manifold, i just chose not to.

 

[dbsupra90]

updates!

flange came in and was welded on, tbody fitted, plate welded on bottom for vac ports, and ming the merciless alt bracket finished. thanks again to sean for all his hard work on it.

my son was proud of the new seat and wanted me to post a pic of that too while i was at it

 

[kwnate]

Manifold looks great! Is that a future mk3 owner in the seat?

 

[X-man]

The manifold passed repeated pressure tests tonite to 50 psi. Now off for polishing.

 

[dbsupra90]

sounds awesome sean!
so i guess i'll set my peak boost to 50psi at let 'er eat. im sure i could go more, but i spose that will be enough.

nate- he is for sure a future mk3 owner. he wants a mk4 too just to have them both

 

[dbsupra90]

update!

just got back from sean's. its really coming together now. we made some pretty good progress over the weekend. and of course, i have pics
here is one for now.
btw, i see my other pics are coming up as red x's now. i moved around some folders so they arent pointing to the right spot anymore. i'll fix that later.

 

[supra90turbo]

Oh that looks amazing Dave!

 

[MK3Brent]

Ha cha cha!
Time for some 3" IC pipes!