Got some new stuff today, and some more batteries for my digital camera, so I thought I would post some pics of my new toys, and some old ones, I took some pics of a GM 6.5 diesel turbo for the people that were speculating on its use in a Rx-7..

Here is my prototype manifold, I carved one out mild steel just to see if I could do it or not, it places the turbo in the same spot as the HKS cast, gonna plant it on the car this weekend to see if that placement is the best or not..


Here is my new T04E for my car..

The Flanges for my final manifold design, laser cut from 3/8 304 stainless, and 304 stainless 2" tube and elbows, I have the cad file for these flanges, if anyone wants some I can get more made..


Here is a comparison of my new Garrett and the old warner ishi off of a 6.5 gm diesel, the exhuast housing is really small, yet the compressor side is pretty decent.


The backside of the warner turbo, the wastegate is pretty large, about 1.25 inches in diameter, the wastegate spring seems to be close to 7 psi.


The exhaust flange on the outlet of the gm diesel turbo is really quite odd, but it could be made, but once again the exhaust side seems to small for a 13b, its a tad smaller than the stock TII turbo exhaust housing....Max

 

hmmm internal wastegate, interesting. First time I saw a real picture of one.

 

hint hint .... talk to some Cummins diesel guys for that exhaust flange ....

 

Interesting looking exhaust manifold you have there. Looks like the front port of the engine goes to the rear of the turbine housing, never seen that before. They don't look to be equal lengths, do you know if that matters?? I've herd that for best results make your tubes 13" long before entering the turbo (think it was riceracing). Anyone?

 

What's the thickness of that pipe and how did you bend it? I'm trying to figure out how thick it needs to be to carry hot exhaust and support the turbo. I have a friend that wants to build a turbo manifold for his car and I told him that I would help just to see if I could do it. Oh, and where it the wastegate flange?
Don.

 

ARE YOU GOING TO BE SELLING THOSE MANIFOLDS YOUR MAKING??? IF SO WHAT ARE YOU THINKING PRICE WISE.....[IMG]underground-motorsports.streetracing.org/images/dust.jpg[/IMG]

 

Gearhead has kinda hit the right nail on the head, what is the wall thickness of that 304SS tube? you need thick walled **** if you use 304 grade, if using 321 grade SS you can get away with 1.5mm (14 guage?) but if running 304 you need around 3mm wall thickness, if running mild steel you need either 3.2mm or thicker steam pipe or 5mm wall thickness.

with a mild steel flange on the motor side, anything thinner than 16mm will warp from the heat. flanges and exhuast tubing on a rotary turbo definitly isn't as easy as normal boinger stuff is.

definitly not equal length either, with divided housing turbo's you get best response and best HP with equal length runners, it allows quicker spool up and overall better flow outta the motor

 

Nice work max!

 

If there was enough interest I would do some more manifolds, I am not really setup for mass production, this was a one off for my own car, but I would do more if people really wanted them.. If I were to sell these things they would be about 350 Canadian (about 215.00 US).. But I would have to sell at least a dozen or two to make it worth my while..
The wastegate piping was not added, I am waiting for my wastegates to arrive, I am using 2 35mm tial wastegates with 9 pound springs. The final wastegate piping will be determined when I get the turbo in the car and see where the wastegates can sit..
The mild steel manifold piping is about a 1/4 inch thick, its sched 80 industrial pipe fittings that we use for ammonia piping at my work.
The stainless is almost 4mm thick, its industrial grade that I got from the scrap pile of an ice cream plant, they had a pile of scrap that they did not need so I found a good home for it..
The mild steel flanges are all 1/2" the chances of it warping,are slim to none provided it was clamped when welded, I build alot of stuff out of 1/2 plate and have zero warparge even under high pressure and high temperature...
The stainless 3/8 is probably even overkill, you coulde get away with 5/16 probably, stainless takes massive pressure and temp changes very well...
I would agree that equaol length runner is better, and when I get the manifold in the car I am going to see if it is doable, but I think it may have more of an effect on a 4 banger than a rotary due to the gaps in the exhaust pulses of a 4 cycle 4 cylinder, If you look at the HKS manifolds they have no provisions for exhaust pulse timing or divisions in the flow, there manifold design is not perfect, but it obviously works..
Astro, I hope everyone is on the road this summer, especially me, I think its gonna be lots of fun with so many high HP cars this next year..Max

 

HWO, thanks for the info. I'm working on a prototype in mild, S/S later.

Max, how much for the divided turbine inlet flange? IIRC, there are dimensions on Turbonetics site, but I'm not sure of their veracity.

Where (or are) you guys bringing the w'gate back into the system. Venting to atmosphere is not an option for me. I'm trying to get the gate 12'-18' downstream, and the return back into the pipe a bit further. Any thoughts?

Also, on the Greddy "divided" manifold for the 3g cars (I'm working on a TII), the tubes actually collect during the last 3-6'. Has anyone else noticed this? I can't imagine why they did this, but its hard to believe they did not have a good reason. Any speculation?

Last, I could be wrong, but I'm not sure equal length runners are possible on the 3g cars - just not much room in there. It'll be close on the TII.
How much un-equalness can be tolerated before there are power losses, or is it significant enough to be concerned about? .25'? I'm not an exhaust expert, so fire away...

Thanks again for the good info,
Steve C.
- learning as I go...

 

What is the model of the IHI turbo? I haven't found on in the junkyards yet and some friends of mine are curious. It should be listed on the compressor housing. I'm looking to put a turbo on a 12A, leaning more towards a T3 (want lots of midrange - high RPM not as important) mainly because I don't have as much knowledge of the IHI units.

So my 1/2" mild steel plate won't be thick enough for an engine flange? Guess I'll have to go to 3/4" or 1" if I can find any.

 

The numbers that I could get off the warner-ihi is as follows:
GM-4
125455
10154652

Thats all I could find on it, if you contact warner-ihi, they may be able to give you some insight on it and maybe a compressor map for it, the relatively small exhaust leads me to think that it is capable of some fairly big boost at low rpm, the compressor side is way huge as compared to the turbine side..

1/2 Plate is easily heavy enough for your flange, the warping really comes into play when its being welded together, not really once its clamped on a running motor. When I weld flanges, I bolt the new flange to the flange face of a cast stock manifold, and it keeps it flat, when you put weld seam down on one side, as the weld cools it tries to pull the outer lip of the flange up, bolting it to a cast flange stops this, one step you can do on thinner materials like 5/16 and 3/8 is pre-heat the flange also, when I built my header for my n/a, I used 3/8 plate, pre-heated to about 900* f, this conforms the flange to the face of the stock manifold, puts the bolt holes in the right place, and then allows you to weld it with a lower amperage setting so you get good weld penetration on the flange without burning through the thinner tubes at the same time...Max

 

High Revs are not important to you?!?! Thats like saying the rotary is not important to you

 

Let's just say I have an enlightened appreciation for a broad torque curve! It does no good to make big power at 8k when you need to come off the corners at 3k, and you blow your engine over 8500! Believe me the only reason I'd even consider a turbo is for the midrange grunt... if all i cared about was high end I'd say screw all that turbo expense and just build up a screamer N/A!

 

That Gm turbo is gonna spool pretty early, probably like a stock TII or earlier, the compressor side being as big as is though, will probably not drop off as low as the TII stocker. The wastegate size is great compared to series 4 and bigger than series 5 TII wastegate, its probably gonna be like a hybrid garrett/hitachi the way it runs, but could be interesting, I thought about sticking it on my N/A, but I am gonna put my TII turbo on it after the TII gets the T04e on it...Max

 

That turbo will come on at 4000 RPM boost to maximum of 1.6bar then drop off to .7 at 8000 rpm, on a ported motor

it spools very fast because it is a 60 trim, too small for a rotary.

you only need one wastegate with that setup one 40mm works fine.

Its very decent for the street, but severely lacks in the top end, not because of backpressure but because it can't push enough air.

 

Which turbo are you referring to magnus, the GM IhI or my to4e?
The T04e is absolutely huge compared to the stock Hitachi, I can't see it dropping boost like my stocker, If I can hold 12 psi to 8000, I will be a happy camper, that should be good for well over 300 rwhp, I have been told that it will be good for 450 if I am brave enough to turn the boost up, but time will tell I guess... The reason for the 2 35-mm wastegates is so the manifold is truly divided with no mixing whatso ever, I went bigger on the a/r (1.15) hot side than what was originally recommended to me (.84-.96) so I want to be absolutely sure I reap all the rewards of having a divided turbine housing...Max

 

I was refering to the GM one with the 4" anti-surge housing. Ours was a 1.3 housing

you will make over 300 hp, but you won't make 450. We have that as our sort of mule turbo, when we don't have a turbo to test with we use that one. It went 11.9 at 10psi, on slicks, then went 11.4 with some better gearing.

You don't need to run two wastgates, you can get the same effect by running two seperate pipes to one gate. But 2 gates certainly looks good

heres pics of what I mean

http://www.magnusmotorsports.com/g-s...s/DSCF0017.JPG

http://www.magnusmotorsports.com/g-s...s/DSCF0018.JPG

 

Thanks for the pics Magnus, I knew what you were getting at, I have been reading alot of material on manifold design, all suggest that there are gains to be had by keeping the runners absolutely seperate, I have no personal reference for this, but if I merged the runners, I think I would always be wondering if seperate ones spooled better..
Thats pic is not far off my final manifold design, excpet my wastegate runners are seperate, and my my runners are a radius transition instead of a saddle style joint, but pretty close...Thanks agian for the info..Max

 

Max,

those runner are completeley seperate into the twin scroll turbine, when the wastegate is closed, you don't have and kind of mixing whatsoever, when it is open you also have no mixing because of the long merge collector on the wastegate pipe.

also to get maximum effiency out of the wastegate, it would have been better for me to put the pipes for the wastegate facing the direction of the gasses, but space wouldn't let me do this, if I had done it that way I would have had more accurate boost control.

I noticed when you move to a larger turbo, or a better match for you application, The manifold wasn't able to control boost like it did befor. Because of the new turbo we're using exhaust gas velocity went up and it starts to bypass the gate, we'd get slight boost creep. By making it easier for the gasses to escape, it'll always work better, gotta make some changes.

Larger turbo's normally need smaller wastegates, but when you get good exhaust velocity with a different header design, you either need a more efficient wastegate exit, or a larger diameter pipe and gate. This can also be said for shorty manifolds vs long tube headers.

Marco