I know somone selling these turbos. The compressor A/R is .60 and the turbine A/R is .84. Would this be 2 much? I get paid today and would like to pick these up. And what would be the pros and cons of these turbos? They are T04B15 turbos. The compressor trim is S and the turbine trim is O. Part numbers are 409250-5002. Thanks.

Brad...

 

No, they would not be too big but here are some problems:

you might have trouble feeding a tangential style exhaust housing like that......you should use an on-center for ease of fitment in a f-body

the s-trim compressor wheel is the lowest horsepower wheel, it makes good horsepower but you cant push the psi very high otherwise it goes out of its range quickly and the air gets too hot

the 0-trim exhaust wheel is the middle grade wheel, it will spool quicker than the favorable p-trim, but wont make as much power.

here is a compressor map for the s-trim:


As you can see, you can make approximately 370hp a piece with these turbos, but that is the EXTREME. Figure with the 0-trim wheel and some small boost.....somewhere around 320 would be reasonable. So for two of them you could make an honest 600hp at least....if not a little more with great spool time and not a whole lot of boost.

If that is all you are really looking for then i say go for it. You can always change the wheels in the future too ya know.......if you outgrow these, just order up some V-trim wheels and make some more power

 

What would be the ideal turbo to use for a TT application. I want to do this right the first time and am willing to spend a bit more to do it. Thanks for the reply. That exhaust port does look a bit tricky to work with now that you mention it. I liked them cause they're new and new is always better. Oh well. The search continues. What would be my main problem hooking exhaust up to these turbos? I can see that they are split, does that create problems? I can fabricate a plate to fit over that real easy if that's all I had to do.

Brad...

 

Use the turbo calculator in the turbo post sitcky. It's pretty accurate and gives a good starting point.

 

i would consult a turbo company and explain to them what you want to do

i think you would be best with a V-trim compressor wheel and a p-trim exhaust wheel. You should probably never run out of horsepower with those. With a good cam and heads you can make unbelieveable power.

www.grapeaperacing.com

he made over 700hp with 12psi and no intercooler with his 385" motor

The easiest way to convert over and save a little money would be to sell those exhaust housings on ebay probably and pick up some "on-center" housings probably at the same place, ebay. They usually aren't expensive....$40 a piece or so

To upgrade the turbos just call a few turbo places on the net and tell them what you want to do and see what they charge

 

Ok, I checked out the GrapeApe site. Love those headers. Looks fairly easy to make too. It looks like those turbos he has are the split exhaust type like the ones above. Now my question(s) are:
In this pic there looks like a pipe coming from the header going to the waste gate. Am I seeing this right? Also, does the exhaust exit right out the back of that turbo facing the firewall?
I found some turbos on E-Bay that might be like the ones you were suggesting. http://cgi.ebay.com/ebaymotors/ws/eB...tem=1848448198
$460 a piece. Is that a good price? Seems to be. I'm gonna go buy a book on turbo charging today so I don't bother everyone with all these questions. As you can tell, I'm totally new to turbos. Never had one in my hands to look at. Are those wastegates he has expensive? Thanks.
After looking some more, on that split exhaust flange, does the exhaust go in one side and out the other that close to each other?

Brad...

 

So when looking at the turbo charts, the x-axis is the amount of HP they make.. is that correct?

 

The turbos that grape ape has not like yours, he has the on-center type exhaust housings. You have tangential housings. THe turbo you just listed on ebay is a much larger turbo. it has a 60mm wheel versus a 52mm wheel of the s-trim wheel. Also, even though in the picture it has on center exhaust housing i believe this is the same seller that i had emailed before and the exhaust is actually tangential.

You should just call up some turbo shops and ask how much to upgrade, you'd be surprised that it isn't that expensive. The only expensive part is upgrading the exhaust wheel, which you dont have to do

 

Is this an on center exhaust housing.? I'm getting seriously confused on these turbos. Tell me if I'm correct? Here is a pic.



Does the exhaust come out the side there where the fins are? if it does, it doesn't look like there is anyway to hook it up to the side. Here is the link to the top 2 turbos in the first post I made. There is more info there. I have to work all weekend so I'll call around Monday about housings. Can you show me a pic of an on center housing so I'll know what it looks like? Thanks.
I think I found an on center pic. That exhaust flange in that pic with the 2 holes has exhaust going in one hole and out the other. Correct? I think I got it figured out now. A bit slow but it's starting to come together now. Thanks.


Brad...

 

nope, that is a tangential. Notice how when the gases would enter that housing they kinda make a loop around to help spool the exhaust wheel....

here is a picture of the different style exhaust housings, hope this helps you out:

 

Don't forget the 3-bolt housing that can be made to work with an integral wastegate

MY TE-64-1


Steve

 

Thanks for the pics. Those are just what I was looking for. I'm gonna call TurboTech on Monday and see how much it would be to convert those housings. I like the one with the integral wastegate. Bet that's spendy though for a new one.

Brad...

 

No need. go here: T3/T4 exhaust housings

 

After looking at those prices,I'd give PTE a call - they list 3 bolt housings(.63 and .85 a/r),4 bolt on-center housings(.69 and .85 a/r),and 4 bolt tangential housings(.58 .69 .81 and .96 a/r) all for $150 each

Steve

 

What size housing/part number would I need for the 2 turbos in the top picture. Thanks.

Brad...

 

In my opinion, no. Turbo chart gives the "specs" of that particular turbo. They are used in compressor selection to get the preferred rev range of the engine to the most efficient area of the compressor.
Horsepower gains depend greatly on the engine the turbo is bolted to.

In this chart the x-axis is air flow, in pounds of air per minute.

the y-axis is pressure ratio, no boost=1.0, 7.35psi of boost=1.5, 14.7psi of boost=2.0 and so on..

the "arcs" with 5 and 6 digit figures are the turbine rpm.

the percentages are compressor efficiency. the lower the percentage, the hotter the boosted air.

sorry for my bad english

 

http://innovativeturbo.com/Turbo%20Tech/turbo_Maps.htm

That should explain how you can estimate horsepower from a compressor map

 

So my theory stands true...

As a rule of thumb, we calculate 10HP / 1 lbs of air @ 100% Volumetric Efficiency, on gasoline powered applications.