goatbrain5.9

I believe it took about 4 weeks but I was kinda laxy dazy on ordering them, I just talked with Donovan and he kinda ordered them whenever he got a chance. So I'm not 100% sure on time

Mike Holmen

Jamie, been wondering about using your stock turbo. I think that the 07's use an electronic wastegate controller. If your going to stay with the stock secondary, I would look into seeing if we modify the housing so we can use the standard boost actuvator and do some work on the turbine housing.

Half the trick to getting twins to kill egt's is to get the primary to lite up. Most twins set-ups, use stock wastegates or turbos that don't flow enough exhaust and will cause the drive pressure to increase (to become restricted)

I seen way to many S300's with cracked turbine housing, chipped turbine wheels. They have casting issues and will not take the egt's that long.

Probably the best wastegate on the market right now is the turbonectic new gen gate. Will flow tons of exhaust.

If it was me and you wanted to run the stock turbo, I would buy the speedsteel exhaust manifold, with a external gate piping. Run a 40-50mm sized external gate. Would be a sweet set-up and wouldn't break the bank accout either.

dodgediesel

I want to go with 2 new turbo's Mike. That way everything will last in a high boost situation. What a pickle. Do I just buy a S300/400 kit or get you to fab me up some? I'm just worried about clearances and such with a fabbed up kit and high drive pressures.

dvst8r

Why would you be concerned about clearances on a kit custom fab'd and fit to your truck? I would think it should be the other way around, more concerned about a box kit, where they have never seen your truck. Sure they have seen many like it, but never your truck.

High drive pressure, is just a matter of flow, lots of options to get around it, some better then others.

StealthDiesel

Well Jaimie, I researched for years before making a decision...

You can read my thoughts here & plus a link to compare the BD R700's to the ATS 3k/5k twins. https://www.dieseltruckresource.com/...ight=ats+twins

http://www.cumminsforum.com/forum/3r...ou-decide.html


There is no such thing as a perfect set of twin turbos, you will have to decide what's best for you.

If you are towing & especially towing with an auto trans, the decision is much more difficult.
The folks who are not towing can get away with murder in terms of lag, surge, drivability, short term EGT's, smoke, etc, etc..
IMO, towing changes everything.

I considered keeping the stock HE351CW turbo but, IMO, any twins kit that doesn't modify the stock turbo's wastegate won't be able to keep the drive pressure down.
Very few twins kits that keep the stock turbo do any mods to it.

I'm biased of course but the ATS twins kit does talk about why & how they modify the stock turbo in their twins kit:

http://www.atsdiesel.com/ats2/produc...und_Turbo_Kits

The install doc is really detailed. 16mb http://www.atsdiesel.com/additionali...dge%20v1.2.pdf

I decided that keeping the stock turbo wasn't worth the compromises for me. If you buy or build a kit that keeps the stock turbo it's difficult to change that up if you decide to later.
Removing the stock turbo allows you to go back to stock quickly & easily in case you decide to sell the truck or write it off, etc..
Plus you will be able to sell the stock turbo for approx $400 if you decide.

If you build up a twins kit on your own, don't forget to add up all the parts. Ex manifold, downpipe, air filter, lower turbo brace, powder/ceramic coating, silicone boots & clamps, etc..
It does add up if you count all the small stuff.


Brad's DDP kit is really nice & as you can see from his dyno numbers, delivered the goods on the dyno.
My kit drives super nice but I haven't leaned on it yet & it hasn't delivered on the dyno yet.. Hopefully this spring.. .

This is all just my opinion.. There are tons of options. Read a ton & ask lots of questions before opening your wallet up!

dvst8r

I hope that didn't come off sounding like a greasy sales pitch.

At the end of the day, I have a full time job sitting at a desk, and the only difference to me if you go with (Source, II, BD, ect...) is that I might have to drink a few less beers in the garage next week.

The reason that I started doing this, was I saw that no one was taking advantage of external gates, and missing out on the big performance gains that come with them. That and I could do a better setup, for the same sort of money.

Mike and I will never be big volume, as we mostly just help people out here and there, and have to work around our own jobs. We just both happen to really like turbos, and even when no one was getting twins from us, we were still out there building sets to try on our own trucks.

dodgediesel

Great write up Joe, thanks buddy
dvst8r, I just need my truck everyday for work. I guess I could drive the Acadia for a bit...

Tate

Is your 3k turbo wastegated?

dvst8r

7 days a week?

dodgediesel

Not on weekends. But pretty hard to pull everything off for 2 days to fit, etc.... What do you and Mike think?

One more thing, I feel like an idiot but what is your name dvst8r??

dvst8r

It's Brett, and we can do fit up one weekend, and install another if that is what is needed to work.

dodgediesel

If that's as easy as it is Brett, what turbo's do you and Mike think will work? Bill @ Source thinks a 62/65/13 over a S475 would be perfect....

Again, I feel like a putz as I should know everyones name by now...

JJPage

I still have to tow in the summer my 32' trailer. If I put on twins and can't tow, my wife will burn my truck and let me try to put it out with the one beer I'm drinking because I can't afford more beer because I bought twins........

I believe you are forgetting your objective!

dvst8r

No worries.

I would do a GT35R with an external gate over an S478.

The 478 has a lighter compressor wheel then the 475 and moves more air. With the 92mm turbine wheel it is also more responsive then the 475 with the standard 96mm wheel, that source typically sells.

The dual ball bearing GT35R, lights and spools faster then anything I have ever run on a truck before. With an external gate we can still get the turbine side out of the way so as not to cause drive pressure issues.

ATS mentions in their installation, when using a stock turbo, about boring out the stock turbo's waste gate opening to 1" ~25mm to reduce back pressure. While this is a good start, all of the exhaust gas still needs to pass through the tiny T3 flange at the mouth of the exhaust side of the secondary HP turbo first. This is the true bottle neck, and why I push so hard for external gate setups. With the external gate we now use either a 44mm or 50mm gate before the T3 flange of the HP secondary turbo. With the 50mm gate you now have the same surface area again as that T3 flange, thus allowing for twice the flow before the bottle neck could occur. The reason I say could is the flow between that T3 flange and the gate are easily equal to the flow of the T6 flange they are feeding at the LP primary.

This has been proven to 1200whp + on the dyno, and 140mph trap speeds. With turbo spreads as large as 62/65/13 over a S595 95mm compressor. It is not often spoken of as the guys that run these setups, have lots of dollars invested in being on top, and are obviously not sold in box sets.

Mike Holmen

Probably can be done. I'm not a smarty guys, but can you adjust at what pressure you can open the wastegate at? Rob and I talked about this some today. Might help you out to dial in the twins if you keep the stocker. Might have to install an old style diapham actuvator to get it to open right.

Was also told that the 07 turbo uses a different turbine inlet flange than a T-3. The S362/S478 would be a great set-up, but like Brett said, external gates really make a big difference, and its worth the extra effort.

I want to buy one of those speed steel manifolds and run a GTX3582R and a GT4718 on my 2010 truck at some point. I would like to run one of those fancy turbonetic new gen gates, just too see for myself. I bet that that twins set-up on a 6.7L would spool-up the GT35 pretty quickly. Might run the AMS gate controller just to try out.

Typically people run to big of a secondary, really all the secondary function is to get everything started, at that point the primary does the work.