turbo manifold project

landtank · 04-21-07, 04:43 PM

now that the old cast manifold has moved on I'm prepared to share my work on a turbo manifold that I've designed.

As others I have borrowed heavily from Dusty's work with weld ells. The design basically posituions the turbo under the manifold and just aft of center. This position allows for a slip joint in the center and should provide ample room up top for plumbing duct work.

Attached here are the drawing files of the tubing configuration and the flange.

landtank · 04-21-07, 04:46 PM

I've cut a corrugated sample of the flange that I'll fit to the engine to make sure everything lines up prior to actually having a iron one laser cut out.

You'll notice that the exhaust gasket fit quite well and there is a provision for the EGR passage

landtank · 04-21-07, 04:46 PM

more

vkfzj80 · 04-21-07, 06:02 PM

Good work Rick, It looks like you're well underway to build the manifold,

Have you picked other components to complete the build?

landtank · 04-21-07, 08:13 PM

I'm still sorting some of that out. I'm getting together with Cattledog tomorrow to further investigate fuel delivery with the stock ECM.

I've got a few irons in the fire right now that need a little more attention before I pull the trigger on having the manifold built and a turbo bought.

But it's getting close.

Dusty · 04-22-07, 09:02 AM

I think the slip joint issue should be considered. I don't think you will need a slip joint and what a pain that will be. just cut the manifold flange between each exhaust port and make the exhaust manifold flange bolt holes a little larger toward the outermost ports (1,2,5,6). these are the suggestions made by Corky Bell in his book with regards to I6 engines. if that slip joint leaks only a very little bit you will smell smoke in the cab and wont be happy. just yesterday a changed out a blown wastegate gasket that was lightly smoking. But at leaste you can change out wastegate gaskets fairly easily

I only cut the flange between 3 and 4 but I did make larger bolt holes towards the ends. My manifold has more room for thermal expansion because it has a pair of secodary runners.

When I built mine I didn't want the turbo any lower than possible to minimize contact with water f I ever cross any.....but then I mounted my air filter lower than the turbo...so go ahead

and I would leave the flange a half inch thick and dont cut it down to fit the exhaust gasket-leave it beefy as possible to make cracks less likely. after you weld it up it will be a bit warped and will need to be machined flat which may loose up to 1/8 and inch in thickness (mine did) in some places.

landtank · 04-22-07, 05:58 PM

Dusty, what do you think about chopping it into thirds. That way I can move the T3 flange center stage and have some meat to hang the turbo from. That would make 1+2, 3+4 and 5+6 as pairs.

I'm a little concerned about cutting them up into 6 pieces with that turbo flange bridging two of them.

landtank · 07-08-07, 11:15 AM

I've been PM'd about updates and finally have something to add to this thread.

About the only thing left from the original design is the drawings themselves.

Using 90* elbows to sweep into the main runner was cost prohibitive and the slip joint fell into the same category as well as getting predictable results was questionable.

So I basically borrowed all the good ideas that I liked from other designs and am using them for my manifold.

Attached is the over view of the manifold as it sits now. The elbows and "Ts" have been cut down to fit properly and chamfered for welding. As some will notice this is how another manifold was built recently.

landtank · 07-08-07, 11:18 AM

The next series show how expansion will be handled. The manifold will eventually be cut up into three sections. The center section bolt holes are round while the outer sections are elongated. Hopefully I've done my math correctly when calculating the expansion differences at operating temps

landtank · 07-08-07, 11:20 AM

The next two pictures shows the chamfered joints prior to welding and the inner runner that will need to be welded and then ground smooth.

MSGGrunt · 07-08-07, 11:21 AM

Looks nice Rick. Did you go with stainless? I'm looking forward to seeing the flange fabricated.

landtank · 07-08-07, 11:25 AM

The next step is to mount the manifold to the head and position the T4 flange and Tial waste gate flange.

Both of these flanges will be sleeved into the main runner. My hope is to hang the turbo underneath the manifold like the AVO and Safari does at a level that will allow the down pipe to pass under the AC line and still go over the frame in the same way that the stock exhaust does.

The turbo that I've purchased is the GT35R with a 3" V-Band flange so it should have enough room to do what I want in there.

landtank · 07-08-07, 11:28 AM

Quote:

Originally Posted by MSGGrunt

Looks nice Rick. Did you go with stainless? I'm looking forward to seeing the flange fabricated.

Everything is 304.

Dusty · 07-08-07, 03:26 PM

precision. fine work
you probably already know the following:

be sure not to make any of your 3 cuts in the flange till all welding is complete as the flange will expand if you do.

have the flange surfaced after the cuts are made as it will be holding some tension after welding is completed and will flex a bit after you cut the flange. if you surfaced before the cuts are made the flange will not be flat

landtank · 07-08-07, 04:10 PM

Quote:

Originally Posted by Dusty

precision. fine work
you probably already know the following:

be sure not to make any of your 3 cuts in the flange till all welding is complete as the flange will expand if you do.

have the flange surfaced after the cuts are made as it will be holding some tension after welding is completed and will flex a bit after you cut the flange. if you surfaced before the cuts are made the flange will not be flat

We talked about this. While I drew up the plans it's two other professionals doing the work. The manifold as it currently sits will be clamped to a 1" piece of steel during welding. Once the entire piece is welded it will be heated to 1500* to stress relieve it and then the two cuts in the exhaust flange will be made. The EGR passage will then be milled and then all three flanges, exhaust, turbo and waste gate will be resurfaced.

I feel fortunate to have these guys working with me on this project.

ls2gto · 07-08-07, 04:27 PM

Looks great, and really professional. Gaps look perfect for welding. Much easier than trying to fit the 90* elbows. A little loss in potential performance isn't a big deal on a vehicle like we have.

Might be worth it to stress relieve the manifold after welding and before milling the flange. It might warp after a few heat cycles due to some internal stresses. Maybe not, but might be worth it if you hate exhaust leaks as much as I do.

I don't know, maybe I've just had some crappy headers in the past...

Any plans to sell these manifolds?

landtank · 07-08-07, 04:54 PM

Quote:

Originally Posted by ls2gto

Looks great, and really professional. Gaps look perfect for welding. Much easier than trying to fit the 90* elbows. A little loss in potential performance isn't a big deal on a vehicle like we have.

Might be worth it to stress relieve the manifold after welding and before milling the flange. It might warp after a few heat cycles due to some internal stresses. Maybe not, but might be worth it if you hate exhaust leaks as much as I do.

I don't know, maybe I've just had some crappy headers in the past...

Any plans to sell these manifolds?

Again, this isn't me doing the work, these guys know exactly what they are doing. All the joints look just like the one I posted. The reason for the sleeves is that they needed to be able to cut into the runner and weld it properly. They didn't want to just layer a bunch of passes over itself to fill in the void.

Attached are some pictures of the parts for the T4 flange. These are just rough parts and they need to be machined for final fit. The end result will be that the rectangle tube will be welded together and then slide into the flange itself.

So the tubing gets cut for the flange port. The sleeve is assembled and machined to fit the hole and welded in. Then the T4 flange is slid over the sleeve and welded into place. The same will be done for the wastegate however the sleeve is just a simple turning on a lathe.

I'll be happy to have more made up if people want them but honestly this isn't going to be a cheap part. But I'm hoping it's a good one.

clownmidget · 07-08-07, 05:07 PM

Rick, that looks beautiful. Don't know if you've made your final decision on where the turbo will sit, but my recommendation is to consider the rest of the "stuff" you want under the hood. For me, I wanted to know that regardless of future mods, the second battery tray, the windshield washer bottle and the grotesquely large cyclonic air filter assembly would fit. And as Dusty has mentioned, the turbo will get so hot it'll glow red after a good run. I know he's counting on his hood liner

but keeping it below the manifold is my vote.

landtank · 07-08-07, 05:33 PM

That stuff has been on my mind for quite some time. Needless to say this build is going in a very different direction from previous ones.

I really have no need for a second battery so that space will be occupied, but my York OBA system should still fit with the stock filter canister in place.

If I get the factory manifolds off and mount this unit for placement I'll shoot some more pics and post them up.

clownmidget · 07-08-07, 07:18 PM

Rick, another thread reminded me to remind you of the factory bracket that supports the y-pipe - the one that has two bolts into the tranny housing. That is a great mounting point for your own bracket to tie in your down pipe housing and really takes a lot of stress off the manifold studs. Another reason to keep it low

Dusty · 07-08-07, 10:17 PM

like Mike said the bracket used by the ypipe is perfect for for support. I'm using mine

sounds like this stainless manifold is built to go the distance. this is one area where I worry about my cast job as I have read that a life expectancy of 5 years is average for a mild steel weld el manifold. mine has multiple welded joints and this can only add to the stress. this stainless job looks immortal. Im sure you will have much more money into this manifold than the ebay one you could have kept. But I have yet to see Rick cut any corners and this build is one more testament

You could have taken a cheaper road than a gt35. Huge power potential. I believe this is the same turbo Christo has spoken of in the past with reference to the AVO kit.

landtank · 07-09-07, 11:29 AM

Using the tranny brace for support has been one of my targets for a while.

Safari and AVO use turbos with internal waste gates. While this simplifies the down pipe and integration into the exhaust system it does get real crowded because of the added width of the turbo housing.

This is the major reason I went with an external waste gate. Another reason was that other cheaper turbos could be used on this manifold.

GreatLakesWaterjet · 07-09-07, 11:56 AM

Rick, lookin' good!

landtank · 07-09-07, 04:12 PM

thanks for all the kind words.

I had an early day today so off came the stock manifolds and on went the turbo one. I've got everything marked out and if I can I'll be dropping it off for completion tomorrow.

Surprisingly my options for turbo placement was extremely limited especially having it down under. In that position there was only 1 spot, so I went with that as my choice.

landtank · 07-10-07, 07:55 AM

I just got back from my machinist and he has everything now to complete the build. He's thinking sometime early next week for the finished product. Sorry I didn't get any pictures but I will next week.

concretejungle · 07-10-07, 08:28 AM

Rick, this is looking good. Very good work from your crew! I am watching all these turbo builds with keen interest hoping that some day i will be able to afford to follow in the footsteps.

Bruneti · 07-10-07, 10:20 AM

Rick, looking very good. Can't wait to see pics next week.

Did your GT35r come with a restrictor for the oil feed? If not, you will need one to prevent smoking. This is a common problem for people using this particular turbo. I think the larger GT series turbos shipped with a restrictor, but the 35r did not. This may have changed now due to some of the early problems people had with it.

http://www.turbobygarrett.com/turbob.../faqs.html#t16

landtank · 07-10-07, 10:48 AM

Quote:

Originally Posted by Bruneti

Rick, looking very good. Can't wait to see pics next week.

Did your GT35r come with a restrictor for the oil feed? If not, you will need one to prevent smoking. This is a common problem for people using this particular turbo. I think the larger GT series turbos shipped with a restrictor, but the 35r did not. This may have changed now due to some of the early problems people had with it.

http://www.turbobygarrett.com/turbob.../faqs.html#t16

Thanks for the tip, if I knew what a restrictor looked like I might be able to answer the question to whether or not it came with one. I'll have to check into it.

Bruneti · 07-10-07, 02:06 PM

http://www.atpturbo.com/Merchant2/me...egory_Code=BCS

Oil inlet fitting for GT28/30/35R with built-in restrictor

Oil inlet fitting for GT Ball Bearing Turbos for GT28R/GT28RS/GT30R/GT35R with built-in oil restrictor (of .035" hole size). Custom machined part. Output is -4 AN male flare. use with any of our -4 feed line assemblies.

Dusty · 07-10-07, 05:03 PM

the restrictor point is a good one. I have used 2 diff restrictors on mine. when my turbo first started smoking I was hoping the problem was too much oil so I went with a smaller restriction but the bearings were coked and the shaft was loose. after I put in the new bearings I went back to the bigger hole and its not smoking. I dont know what to think on this one. But I do know that most turbos need only a fraction of the oil pressure available to operate properly.