DI Street Twin turbo compound project

[Big Bore]

did you enlarge the hole and cross drill the volute to wastegate both sides of the up pipe collector? If memory serves right the flapper disc is a good bit larger than the stock hole and could be enlarged some.

What size would you crossdrill? Same size as the wastegate hole?

 

[psduser1]

What HP range were you shooting for?
Nice looking job, do you have any pulls/runs/seat time yet. I'm really curious about your impressions with the tighter housing on the 38.

 

[PowerstrokeJunkie]

Me, personally I would drill as large of a hole as I could and smooth down the edge with a die grinder

 

[Hotrodtractor]

One question though- since you are relying solely on the small flapper valve for the wastegate, did you enlarge the hole and cross drill the volute to wastegate both sides of the up pipe collector? If memory serves right the flapper disc is a good bit larger than the stock hole and could be enlarged some.

I've seen that done before with excellent results on a hard fueling stock charger truck. It works quite well and maintains a good balance between the back pressure in both volutes. I have tested it myself, but was rather surprised when I was told what the pressure differential between the volutes was before the modification. I don't have the data, but it was very significant.

 

[PowerstrokeJunkie]

Well, it only makes sense. The left and right sides are completely isolated until the turbine wheel, and I don't see why more people don't do this to stock turboed/38r trucks

 

[Big Bore]

Well, it only makes sense. The left and right sides are completely isolated until the turbine wheel, and I don't see why more people don't do this to stock turboed/38r trucks

Seems to me that there would be a significant heat differential between the two sides if you were fueling hard enough to need the WG.

OTOH, why does a stock truck even need a WG?

 

[Hotrodtractor]

Well, it only makes sense. The left and right sides are completely isolated until the turbine wheel, and I don't see why more people don't do this to stock turboed/38r trucks

More people don't do it because its not talked about on the internet. If someone wrote a DIY - then it would be the cool thing to do and everyone would shrug it off like its common knowledge at that point.

 

[Cat_rebel]

More people don't do it because its not talked about on the internet. If someone wrote a DIY - then it would be the cool thing to do and everyone would shrug it off like its common knowledge at that point.

Most of the Cummins guys I talked to crossed drilled their stock HX35 to use on a Ht3B compound kit & have done it that way for years.

 

[JAP]

I cross drilled mine as well as removed the divider and ported the wastegate hole a while back. I haven't reinstalled the turbo yet though.

 

[Marty]

Nice Dave.

 

[Powerstroke Racer]

Nice Dave.

Thanks.

 

[Powerstroke Racer]

I asked the owner of the truck to give his input on here as he drives the truck everyday.

 

[Sinister 7.3]

First off just wanna thank David for the killer street setup on my truck. This is my first built diesel and got bit by the bug really quick. As far as the truck goes with the compound setup it's definantly a HUGE step up from a single turbo, running this set up is amazing it reminds me of running my 496 bb with a 242-248 cam the power comes on so smooth and comes so quick off the line and is always on tap anytime I wanna dig my foot into the pedal the power just seems endless. Since the newness is wearing off and I got back to everyday normal driving the streetability is amazing there is almost 0 lag in normal conditions,rolling out of a stop light both turbos instantly light and I don't feel any stutter anymore. Rolling down the street and hitting it hard there isn't any wait for the turbo to boost anymore it picks up as soon as the pedal is touched and rolls hard (like a cammed out big block). The truck is definantly alot of fun gets a little sketchy sometimes when I'm rolling at 35 and dig into the pedal and the rear end whips around on me faster than I can think about it but the faces are priceless when I line up with cameros, mustangs and all the other diesels running around town and just blow em down. Looking forward to finishing the build up this next year

 

[BlueWaffle]

vids.....do it.

 

[Sinister 7.3]

The truck definantly makes alot of people think twice when I pull up on their left side and they catch a look at my fenderwell

 

[Dmstrucks02]

We need some videos!

 

[golfer]

First off just wanna thank David for the killer street setup on my truck. This is my first built diesel and got bit by the bug really quick. As far as the truck goes with the compound setup it's definantly a HUGE step up from a single turbo, running this set up is amazing it reminds me of running my 496 bb with a 242-248 cam the power comes on so smooth and comes so quick off the line and is always on tap anytime I wanna dig my foot into the pedal the power just seems endless. Since the newness is wearing off and I got back to everyday normal driving the streetability is amazing there is almost 0 lag in normal conditions,rolling out of a stop light both turbos instantly light and I don't feel any stutter anymore. Rolling down the street and hitting it hard there isn't any wait for the turbo to boost anymore it picks up as soon as the pedal is touched and rolls hard (like a cammed out big block). The truck is definantly alot of fun gets a little sketchy sometimes when I'm rolling at 35 and dig into the pedal and the rear end whips around on me faster than I can think about it but the faces are priceless when I line up with cameros, mustangs and all the other diesels running around town and just blow em down. Looking forward to finishing the build up this next year

:thumbup:

 

[Sinister 7.3]

I'll see if I can get some videos shot and posted this weekend

 

[Tim @ P.I.S.]

Looks good Dave.

Very curious to see testing reults to see if a WG is needed. If no extra gates are needed that seems to be a somewhat simple compound setup.

Was adding the 45R the only thing changed??

 

[Cat_rebel]

What are you running for boost cruising?