LB7 Y-BRIDGE MODIFIED

[1FastBrick]

I saw a post were YellowChevy modified one. Not sure if he is still active or messing with that sort of stuff. Other wise you are on your own or left to purchase something off the shelf.

LB7 Y-bridge

Fabricated a y-bridge for guy a few weeks ago and thought I'd put it up here for those that don't get on social media. I'm not a master aluminum welder, I can actually count the number of times I've tigged aluminum on 1 hand, haha. I'm very happy with how it tuned out and would like to thank...

www.duramaxdiesels.com

 

[Fastshovelhead]

I remember reviewing that Thread, that's some Serious Plumbing

 

[Bdsankey]

What are you looking to gain? IMO you aren't going to see any major "seat of the pants" gains as the LB7 bridge is already pretty decent unlike the later years.

 

[Fastshovelhead]

What are you looking to gain? IMO you aren't going to see any major "seat of the pants" gains as the LB7 bridge is already pretty decent unlike the later years.

Wasn't looking for any HP gains, just looking for a full 3" transition from the 3" intercooler cold side. (eye candy)
There's not much left for me to do besides dropping the Allison & doing a full Build. I primarily tow with this unit & Keep it in the low setting to prevent a limp mode situation.

 

[Bdsankey]

I don't know anyone who modifies them. I know WCFab sells their 3" version that costs a pretty penny.

 

[Fastshovelhead]

I don't know anyone who modifies them. I know WCFab sells their 3" version that costs a pretty penny.

I know WCFab use to build them by using the lower half of the OEM core.
I've tried reaching out to them by Phone in the past, but have never been able to make contact.
My though was to sent them one of my Y-Bridges & have them build it up the way they use to, prior to their latest CNC design that requires the installer to cut part of the fuel system hardline & install Rubber line & T in its place.
Yes, there're Pretty Proud of it !

 

[Bdsankey]

I know WCFab use to build them by using the lower half of the OEM core.
I've tried reaching out to them by Phone in the past, but have never been able to make contact.
My though was to sent them one of my Y-Bridges & have them build it up the way they use to, prior to their latest CNC design that requires the installer to cut part of the fuel system hardline & install Rubber line & T in its place.
Yes, there're Pretty Proud of it !

Good luck on the bolded statement (and I can't blame them). Sadly it'll take a tech far too long to modify your OEM bridge (I'd imagine if they did it they would charge by the hour) where that fabricator could be making them more money doing full orders/helping the backlog than a $200-$400 modified OEM y-bridge. I am not trying to sound like a negative nancy, just want to explain their potential side of the coin as I've been given this answer before on other jobs with them.


If that's something you wanted inquire on them doing I would suggest sending an email, it seems to be the best method to get ahold of them in my personal experience.

 

[1FastBrick]

Based on this image, It would appear you would have to modify the return line on just about any off the shelf 3in. Y-bridge any way.
There is a guy selling just the flanges on Ebay if you want to build your own Y-bridge from scratch.

 

[Fastshovelhead]

Based on this image, It would appear you would have to modify the return line on just about any off the shelf 3in. Y-bridge any way.
There is a guy selling just the flanges on Ebay if you want to build your own Y-bridge from scratch.

I have a Couple of Bridges to spare

 

[1FastBrick]

If that will work for what you want, Why not just buy it then?

 

[Fastshovelhead]

If that will work for what you want, Why not just buy it then?

That photo was the old Style & I haven't found one yet.
I've only found the Newest CNC Model available.

 

[Bdsankey]

That photo was the old Style & I haven't found one yet.
I've only found the Newest CNC Model available.

Here's the picture right from their website.

 

[Fastshovelhead]

This is the new style that requires the cutting of the hardlines, It's not what I've been looking for.
It looks Really Nice But that's not it.

The Photo below is what I've been looking for.

Am I the only one that can see the difference here in the new & old design? lol

 

[Bdsankey]

This is the new style that requires the cutting of the hardlines, It's not what I've been looking for.View attachment 114243
It looks Really Nice But that's not it.

The Photo below is what I've been looking for.

Am I the only one that can see the difference here in the new & old design? lol

View attachment 114244

We can see the difference, but this is one of those things where you're going to have to either make one yourself or modify some parts. You'd be cutting a return line and removing (or better yet relocating) the FPRV.

 

[JoshH]

I think I would rather have the new style.

 

[Vmyrhaug]

i made my own from steel. and made flow direction change smooth. i thing on high boost, the stock one pushes more are too left side cylinders.

 

[wydopenLb7]

How much of a difference do you see between an aftermarket and federal lb7 bridge by itself? Mine needs to be changed. Going to do manifolds and Up pipes at the same time.

 

[Bdsankey]

How much of a difference do you see between an aftermarket and federal lb7 bridge by itself? Mine needs to be changed. Going to do manifolds and Up pipes at the same time.

Hardly any benefit to a different bridge or manifolds/up-pipes, especially on a stock turbo. IMO manifolds/up-pipes are unnecessary until the 800whp area, meaning that the gain is not worth the money in my opinion until then.


The best "bang for the buck" on manifolds/up-pipes is an LML driver side manifold and 2' up-pipes. You get most of the benefits of the $800+ aftermarket setups for less than half the cost.

 

[1FastBrick]

@Fastshovelhead This kit just popped up for sale and I think it has the Y-bridge you want...

https://www.duramaxdiesels.com/forum/threads/wcfab-s475-over-stock-kit-lb7.89427/

 

[wydopenLb7]

Hardly any benefit to a different bridge or manifolds/up-pipes, especially on a stock turbo. IMO manifolds/up-pipes are unnecessary until the 800whp area, meaning that the gain is not worth the money in my opinion until then.


The best "bang for the buck" on manifolds/up-pipes is an LML driver side manifold and 2' up-pipes. You get most of the benefits of the $800+ aftermarket setups for less than half the cost.

I'm assuming a downpipe is worth doing? The stock one looks pretty restrictive..