DOHC turbo placement and compressor maps

r3v3rs3 · Post by **r3v3rs3** » Tue Sep 26, 2006 3:45 pm

So I was thinking about turbocharging, though I'm in no position whatsoever to attempt it (read cheap)...

http://www.cardomain.com/ride/167457/5

Stumbled on this guy's car while browsing, and aside from the tiny turbo, crappy welds, etc, etc, I lke the idea of putting the turbo at the end of the stock manifold. How much can those manifolds be hogged out over stock, anyways?

What I'd like to see is that turbo location, a big air-air intercooler placed behind a taillight panel cut out in the center, and throttle body mounted directly on the plenum. Would it work? I have no idea.

The other thing I've been doing is plotting compressor maps for the 3.4 DOHC, which Howard made extremely easy (and fun!) with his turbo spreadsheet.

http://www.putfile.com/gok4rt/images/26451

So my questions: first of all, am I doing it right? Second, it looks like the GT80 would be the most efficient match for the DOHC, but would this mean it's gonna be super laggy (besides being expensive as all get out)? IIRC, someone recommended the T4/60-1, but it looks like it would be relatively inefficient across the whole powerband, though still on the map at least.

Kohburn · Post by **Kohburn** » Tue Sep 26, 2006 4:00 pm

while those maps show the redline they do not show the whole picture (meaning the whole powerband)

these are some i put together for choosing my turbo

i based the engine VE on dynos of other 3.4dohc turbos and used that for plotting the rpm range

i also did them by hand

IMO those two are the best fit for the 3.4dohc and MY power goals -

a T04E-60 will work well for around 300hp and quick spooling

Kohburn · Post by **Kohburn** » Tue Sep 26, 2006 4:03 pm

here are two of my custom intakes

http://img.photobucket.com/albums/v435/ ... m_0959.jpg

http://img.photobucket.com/albums/v435/ ... m_0748.jpg

and here is my intercooler

Shaun41178(2) · Post by **Shaun41178(2)** » Tue Sep 26, 2006 6:03 pm

I would try to move that fan closer to the inlet of the intercooler. most of the cooling takes place within the first several inches, not in the middle

r3v3rs3 · Post by **r3v3rs3** » Tue Sep 26, 2006 7:21 pm

Kohburn wrote:while those maps show the redline they do not show the whole picture (meaning the whole powerband)

these are some i put together for choosing my turbo

i based the engine VE on dynos of other 3.4dohc turbos and used that for plotting the rpm range

Ah, I see... But it's still not the whole picture, because you're not making 13 psi across the entire rev range. You'd need to base it on the data from another DOHC turbo's MAP or something, I don't know.

BTW, what are the dimensions of that intercooler? I need to read through your build thread again...

Kohburn · Post by **Kohburn** » Tue Sep 26, 2006 10:14 pm

if you look at the lines drawn on the other two pics then you can see where the lower boost levels sit on the graph

Post by **eHoward** » Wed Sep 27, 2006 9:28 pm

how do you figure?

Shaun41178(2) wrote:I would try to move that fan closer to the inlet of the intercooler. most of the cooling takes place within the first several inches, not in the middle

Shaun41178(2) · Post by **Shaun41178(2)** » Wed Sep 27, 2006 10:18 pm

Intercooler is a big heat sink. The greatest temperature variation at the intercooler is right where the hot air from the charge piping hits the intercooler the intecooler is cooled from ambient air flowing over it. If that temp is 100 and outlet temps are 300 then right at the beginning of the intercooler, the temps drop the quickest because of the greater temperature variation between the two. As the air starts to cool as it travels through the intercooler, the temp difference from the charge air and the ambient is less, so it cools slower but still cools.

I also read it somewhere too. Itnernet. Maybe H-T. It makes sense to me as to why it is that way as well.

Chris-Nelson · Post by **Chris-Nelson** » Wed Sep 27, 2006 10:31 pm

um, maybe 2 fans??

Kohburn · Post by **Kohburn** » Thu Sep 28, 2006 7:34 am

the fan is at the 1/4 and 3/4 positions since the intercooler is a down and back setup - its a non issue - if it needs to be cooler then i'll add a pressure trigger to activate a CO2 sprayer

no room for more fans, the single fan is jammed between the trans mount, the front engine mount and the firewall

Kohburn · Post by **Kohburn** » Thu Sep 28, 2006 3:55 pm

just found this - it is exactly what everyone needs, especially on OE

http://www.turboneticsinc.com/downloads ... Matrix.pdf

Series8217 · Post by **Series8217** » Thu Sep 28, 2006 5:21 pm

awesome!

r3v3rs3 · Post by **r3v3rs3** » Fri Sep 29, 2006 2:03 am

Woot! Why didn't anyone think of that before?

Kohburn · Post by **Kohburn** » Fri Sep 29, 2006 8:36 am

i wonder if garrett has one - because this one is just turbonetics turbos and does not have GT turbos in there - they do however have ceramic ball bearings as an option.

i did however find a supplier of the exact turbo setup i was looking for.

a 62-1 t3/t4 setup - its a direct bolt in replacement for my t04e, but flows a ton more air much more efficiently - so i'll be getting the 62-1 with a .63 stage 5 exhaust - think its the big shaft 360* bearing version for 800$

3000,4000,5000,6000,7000 rpm at 6,10,14 psi

XzotikGT · Post by **XzotikGT** » Sun Oct 01, 2006 9:19 pm

Well, since I it is my car in that cardomain picture I feel a need to speak now. First of all the Turbo is Far from small. It is a T04b H-3 trim. It has an .82 AR exhaust side and a .70 cold side housing. So, from this turbo is plenty enough for my setup. It spools pretty quick, and will reach full boost by 3000 rpms, which was set to 10-12psi. Really I dont see how you can look at a turbo and tell if it was small.

Now, the pictures I posted on the Cardomain site, I admit are pretty bad. That was my first time ever touching a welder, and I did not care if it looked good at that point I just didnt want the thing to fall apart. I have since redone the whole system, and now it is 100% beter. I have had a lot of help lto get the car to the point that it is at now.

The car suffered a lot from tunning, and when I blew a head gasket. I found that the motor was damaged from the previous owner. So, Took the heads got them O ringed, and had a major port done. I had them open up the ports as large as possible, knife the runner, some bowl work.
To top that off I had a custom intake manifold done up. Now I am working on a new tailight section that will alow me to place an intercooler in the back, and vent out the back.

The turbo location is the best I could think of, and after letting several turbo experts view my setup, they thought it was perfectly fine. to put the turbo on the crossover area on the 96+ motor, you would need at the very least exhaust manifolds made. The stock mani's are designed to flow a certain direction. Also there really isnt much space to place a turbo reasonably back there anyhow.

SO yeah the pictures were from the day I finished putting it together inititially. It wasnt a finished product. I was just proud that I actually made something, and it worked.

So good luck to you, with your project.

Kohburn · Post by **Kohburn** » Sun Oct 01, 2006 9:44 pm

yeah i looked at the super-H3 turbo - but decided to step it up a notch for better efficiency. if the headgasket goes before 400hp then i'll probably get custom gas filled o-ring cometic head gaskets.

r3v3rs3 · Post by **r3v3rs3** » Mon Oct 02, 2006 6:31 pm

I apologize. At the time I was plotting maps (incorrectly, as it turns out) that all said a high-flowing 3.4 L needed something like a GT80, which is pretty much overkill. As for the rest of your project, I'm glad to hear you got some better plumbing on there, and as I said originally, I like your placement and intercooler ideas.

Good luck to you, too. :thumbup:

Kohburn · Post by **Kohburn** » Mon Oct 02, 2006 6:43 pm

gt80? are you on crack? did you steal eb's car and leave it in the middle of the street?

Shaun41178(2) · Post by **Shaun41178(2)** » Mon Oct 02, 2006 9:11 pm

:rotflmao:

r3v3rs3 · Post by **r3v3rs3** » Wed Oct 04, 2006 12:13 am

You can't judge me! Who are you to judge me?