Turbo dump pipe size?

[Hombrey]

Guys I've got a T28 on my TD 42. Thinking about going to a 3 inch exhaust but interested if others running 3 inch exhausts have also changed up to a 3 inch dump pipe off the T28 turbo or have you just hooked the 3 inch up to a 2.5 dump?

[crazyclark31]

would assume t28 is bout same size as a tdo5 which i'm running. I just run a 3in from turbo straight through to tip. No muffler either and is surprisingly quiet.

[Hombrey]

So is the dump coming out the back of yours 3inch? Mines 2.5 at present so to change I think I actually need to change the exhaust flange on the turbo up to a 3 inch flange if necessary. Easier to just upsize the pipe after the exhaust flange on the turbo but don;t see the point if its still going to be restrictive.

[Hombrey]

Also hows your power? I'm chasing some better performance? Have the turbo and just had the injectors done up but the truck just does not seem to be performing like I've heard others talk about. Added a 1/2 turn to the fuel screw and driving to keep EGT's under 550 or 600 sometimes but its still no rocket. I'm wondering if the 2.5 dump pipe and exhaust is strangling it. I'm running up to about 13lb of boost and truck has done about 300ks. I run outta power at about 3400 revs. Pushing past 100k is a kinda sluggish process and am on 33's.

[Big Will]

Have you got an intercooler?

[Hombrey]

Not fitted yet but is in the shed waiting for a weekend. Going air to air with a scoop. I'm thinking I'll do the exhaust then if its still not great I'll look at the injector pump. Thats still stock at present and I doubt its had a spanner on it except when I did a top seal.

[crazyclark31]

have 3in straight off the turbo.when it did mine i just made the flange a direct copy of the trubo housing then welded the pipe to it.
Mine is running 10psi full turn of the screw. Goes like a rocket considering. On 33s my 100km/h time is 12 1/2 secs.
Holds its boost right upto and past red line.

Would deffinatly be going 3in all way through.preferably with mandreal bends. Deisels love no back pressure.

What size T28 you running? most go for the .64hot side.

[Big Will]

Honestly front mount is the key.
get that EGT down then fuel the hell out of it!!!

[crazyclark31]

Honestly front mount is the key.
get that EGT down then fuel the hell out of it!!!

yep to that!!

[Hombrey]

Turbo glide kit. says a/r 60 on the inlet side. Cast 90 degree flange off the back so I'm thinking inside diameter is probably smaller than 2.5.

Not sure my trucks ever seen the redline mate. Boosts pretty well. Runs about 3lb cruising at 100k in fifth and boosts straight up to about 13lb if I floor it but just does not seem to accelerate that well hence thinking its restricted. Sometimes though if idling at the lights for a bit then floor it, it will pull up to 3500 no prob but after that its back to sluggish. Fuel filter has been replaced to.

12.5 secs is quick. Be surprised if mine got there inside 20. Thats a big difference. And my egts climb quick too. Re intercooler. Na im in the mud a bit so a front will clog fast mate.

[crazyclark31]

yeh would say the dump is a cause. What kinda air filter you using as they can be restrictive aswell

Mine use to do 21 sec to 100 before i turb'd it.

[Hombrey]

Came in the kit as the kit replaced the filter box etc and put it up in the front corner behind the left head light. Is a paper element cylinder type one. Have pulled that out though and tried the truck and it makes little difference.