Okay....<br>I have posted this on some other sites too...just getting some all-around info. <br><br>A few weeks ago I purchased another turbo. I am about maxed on upgrades otherwise and the custom diesel shop I use in Atlanta has already made some new decals for me...currently on the sides over the 2500 plates are 500 HP decals...and the new ones read &quot;600HP Twin Turbo&quot; ;D <br><br>All I would be looking at spending is about $500 on the tubing to fabricate the system. I already got the head O-ringed and had them check some other stuff to make sure I was in good working order...now all I need is a reason not to do it!!!<br><br>100 more rear-wheel horsepower is an intoxicating thought!! <br><br>I'll keep ya'll updated as to what happens...probably a couple weeks though 8)

 

What kinda &quot;big&quot; turbo is it? If all it's going to cost you is $500, and you have all the tools, then go for it. I would HIGHLY suggest talking to Jim Fulmer of the TDR before you do it. Also check out his thread HERE for great tips. <br><br>Andrew<br><br>P.S. If you need his e-mail address, let me know.

 

What &quot;small&quot; and &quot;big&quot; turbos would yall recommend? I have decided to go for twins on mine later on down the road but don't know how what turbos to use. An HX35 16CM2 non-wastegate pushing a Piers HX40 (don't know housing size or whether to get with/without wastegate)?

 

A HX-40 is waaay too small to be a secondary. You need to look more in the HX55, HX60, HT3B, or T-88 range. HT3Bs are quite cheap and seem to be the secondary of choice lately. Housings vary on the secondary from 22 to 32 cm2 and primarys from 9 to 18cm2. If you're using a HX35 as the primary then you definitely want to wastegate it.

 

[quote author=banshee link=board=7;threadid=7313;start=0#70110 date=1037826561]<br>A HX-40 is waaay too small to be a secondary. You need to look more in the HX55, HX60, HT3B, or T-88 range. HT3Bs are quite cheap and seem to be the secondary of choice lately. Housings vary on the secondary from 22 to 32 cm2 and primarys from 9 to 18cm2. If you're using a HX35 as the primary then you definitely want to wastegate it.<br>[/quote]<br><br>The cost of that T-88 might make you change your mind about using it. It is half the cost of some twin systems I have seen. That Ht3b is the perfect for cost reasons. But that T-88 is PERFECT in effency reasons.<br><br>Looking at HVAC's truck can be a REAL learning experence even though I have seen Gene's(sled Puller), Jim Fulmer's, Mark Kenndrick's, Eric McBride's, and Jeff Prince systems before, not to menetion others. ;D ;D ;D<br><br>BB,<br>How tuck another $4,000 away for the twins of you decide to buy a set. :'(<br><br>Andrew

 

The T-88 is too small for his 12 valve as a primary charger.<br>With his high timing ( 40 degrees)I will only guess he revs it up a bit higher than most. The T-88 is out of air past 3000 even for nominal manifold pressure.<br><br>Don~<br><br>yep I said primary, the secondary charger is the one closest to the engine or the one that receives the air charge second.<br>The secondary charger also receives the exhaust first. It is the second stage in the compression equation. I see everyone referring to the small turbo as the primary, it just aint so.<br><br>

 

Just to help settle ya'll down a bit... ;D <br><br>My Primary will be my current Piers HX-40, and my secondary will be an HX-55.<br><br>Hope this helps ya'll...<br><br>And yes I can rev it wayyyy out....I can be cruising down the interstate, floor it, and still feel seat-sucking acceleration up through the end of my tach's range.

 

Actually Don, most people I have talked to say that they want the little turbo to do MOST of the work, therefore leading to the reason it's called the primary.

have you played with a turbonetics t-88 or a g-ready t-88? 2 different animals.

As for the 40* of timming, missed that...

Andrew

 

Andrew,<br><br>The small turbo next to the engine or bolted to the exhaust manifold is the one that receives the compressed air from the larger turbo second. It then takes that compressed air and compresses it again. This is how compounding the pressure ratio works to give the higher manifold pressure or boost everyone thinks they need. Yes the litte or secondary charger gets the exhaust gas first and actually feeds the engine the compressed air charge from its compressor side, but it is still the second stage in a staged or compound turbo system. <br><br>When the turbos are matched together to get the proper pressure ratio they are figured backwards. The primary charger ( the big one) is worked up first by its map and then the second stage is worked into the equation with its map. It all goes by ambient conditions you live in like: high or low altitude, rpm range you operate the engine at and its volumetric efficiency, desired manifold pressure, and the type of charge air cooling you will be using. Just to scratch the surface. <br><br>For the rpm range he will be operating at with 40 degrees of timing the T-88 in any trim is too small.<br><br>The little turbo is and always will be the second stage in a compound system.<br><br>Don~<br><br>

 

Don~

thanks for writing all that, but I allready know how twins work, I ahve done my homework.

However, Nowel calls the little one the primary, and the says his systems use the primary to do most of the work, reason being that it (the smaller primary) does more work by spooling all the time, and the second one doesn't do anything untill about 15-20 psi of boost(depening on the matching). Jeff Prince also is a thinker of this school. He wants his small turbo to do most of the work, and only use that big turbo when it's really needed. Least that's how they told me.

Your &quot;preaching to the chior&quot; trying to tell me about twins. :-*
Andrew

 

Don M or others: V8s and some V6s have twin turbos in parallel (one on each bank). If you fabricated two exhaust manifolds (three cylinders each) for the 5.9 Cummins and installed two HX35 turbos with the compressed air combined to the intercooler, what would the performance be compared to a single big turbo or two turbos (large and smaller) in series? What are the advantages and disadvantages of each configuration: large single; twin parallel; and twin series? I am thinking of minimizing egts while towing and acceptable turbo lag.


I also found this:

http://216.235.147.117/forums/showth...el+twin+turbos

 

[quote author=BoldtsWagon link=board=7;threadid=7313;start=0#70630 date=1037902548]<br>Don M or others: V8s and some V6s have twin turbos in parallel (one on each bank). If you fabricated two exhaust manifolds (three cylinders each) for the 5.9 Cummins and installed two HX35 turbos with the compressed air combined to the intercooler, what would the performance be compared to a single big turbo or two turbos (large and smaller) in series? What are the advantages and disadvantages of each configuration: large single; twin parallel; and twin series? I am thinking of minimizing egts while towing and acceptable turbo lag.<br><br><br>I also found this:<br><br>http://216.235.147.117/forums/showth...el+twin+turbos<br>[/quote]<br><br>One reason is that the cost would be much higher then a compound setup because of the exhaust manifold would have to be custom fabed. This does not mean it couldn't be done. Also, Kurt (the B-1 maker) said it very well to sum it up....<br><br><br><br><br>have fun,<br>Andrew

 

Fellas,<br> I have read a few posts regarding twin turbo's but I am having a hard time picturing how it is actually set up. Do any of you have a picture to show ? <br><br> Thanks,<br><br>PISTOL

 

Don,<br><br>Makes sense on the naming of primary &amp; secondary. Like Andrew, I've seen it called both ways, but it made more sense to me that that closer to the engine would be primary. I was thinking along the same lines but on the exhaust side. A matter of semantics, but thanks.<br><br>On the sizing, I was answering BigBlue about what size to use... just giving him a ballpark to start looking at. I hear the T-88s run close to 2k... pretty spendy. It makes you realize why everyone is using the $500 HT3B as the primary of choice

 

John,<br><br> Primary choice.....hehe<br><br>Don~