[TechFrontier]

Hey everyone, I know that a lot of us have always wanted to throw a turbo on a vqd40 and run boosted. Although I may not be the most talkative member I'm planning on sourcing all the parts to put together a front mount turbo kit, I'm not going to do it like most systems would usually do with mani's that are facing the front of the vehicle. I'm planning on running the exhaust from where the b pipes exit to the rest of the exhaust and run a forward facing y pipe and then hard pipe 2.5" all the way to the engine bay. From there I'm planning on running a pretty normal front mount turbo. I've done some supporting mods already like remove all the plastic shrouding and electric rad fans.

The next thing on my list of parts is a 255lph Walbro fuel pump. which I just ordered this afternoon. More updates to come!

Sent from my iPhone using Tapatalk

 

[phatB]

cool, looking fwd to the build.

is 255 lph enough? i thought that was like the standard 4 banger wrx upgraded pump. i have no idea what the stock pump flows.

 

[TechFrontier]

In order to boost 5-7 pounds for a fronty a 255 will work, I looked up a replacement for a stock fuel pump and it flows 28 gallons per hour at 51 psi, a gss342 255 LPH flows 50 gph at 80 psi. Should be plenty to get 5-7 pounds of boost easily without leaning out.


Sent from my iPhone using Tapatalk

 

[whistler]

Stock vq40 psi is 55psi.
You are going to need a regulator.
You will more than likely need a return line.

 

[TechFrontier]

You are going to need a regulator.



Rising rate FPR correct?

 

[whistler]

Not sure what you mean. You need a regulator because you are bypassing the stock system. It is the only way to adjust your psi.
Also I am pretty sure you will need to Fab a return line. The stock system uses pulse width modulation to control fuel delivery. All done by the computer . Does not work with after market systems.

 

[TechFrontier]

Not sure what you mean. You need a regulator because you are bypassing the stock system. It is the only way to adjust your psi.

Also I am pretty sure you will need to Fab a return line. The stock system uses pulse width modulation to control fuel delivery. All done by the computer . Does not work with after market systems.

In order to keep proper fuel pressure under boost it'll need a rising rate fuel pressure reg. And I have all the tools and equipment needed to make fuel lines so I've got that down.

Because I'll be bypassing the stock fuel pump, I'll need to wire this pump to a 12v switched source?


Sent from my iPhone using Tapatalk

 

[whistler]

My pump is wired into the stock wiring. I used Weatherpack connectors since locating stock a stock connectors are hard to find. You can see the connector in the photo.
Fuel pump turns on with key.
Are you going to use your stock tank or a fuel cell?

 

[TechFrontier]

My pump is wired into the stock wiring. I used Weatherpack connectors since locating stock a stock connectors are hard to find. You can see the connector in the photo.

Fuel pump turns on with key.

Are you going to use your stock tank or a fuel cell?

At first I'll be going with my stock tank, eventually I'd like to upgrade to a 30 gallon fuel cell so I can put more mileage per tank. My truck is pretty much a daily driven mall crawler so I don't really have any concerns with off-roading wear and tear so it's not a big concern with using my stock tank for now.


Sent from my iPhone using Tapatalk

And FPR ordered, just need to buy the SS fuel line and -6AN fittings.

Sent from my iPhone using Tapatalk

 

[whistler]

Does that regulator increase fuel pressure as fuel demand increases?
Not sure how you are going to rig your stock tank. Outlet should not be that big of a problem. You are going to have to rig something for your return.
Also ,do you have smog checks in your state? Won’t pass here in California.

 

[whistler]

Friends built turbo systems years ago. One on a 327 . One on a 240z. A 1975 International diesel six banger. One on a Suzuki motorcycle.
Action Fours built a turbo system for Honda Fours for drag racing. Problem was turbo lag. Fixed it by having a bottle of nitrogen with a small jet that was aimed at the impellers. Hit a button that gave instant boost,
The Honda Hawk land speed bike ran two turboed motors. We ended up with the cases.
Friend helped design it.
Not exactly sure what you mean by b pipe. Your not concerned with lag?
Spending too much time here again.
Need to deal with the race season coming up.

 

[TechFrontier]

Does that regulator increase fuel pressure as fuel demand increases?
Not sure how you are going to rig your stock tank. Outlet should not be that big of a problem. You are going to have to rig something for your return.
Also ,do you have smog checks in your state? Won’t pass here in California.

Yes that FPR is a 1:1 boost/vacuum rise ratio. And I think for the return I'm going to try to get some SS or aluminum pipe the same diameter of the filler tube, drill and weld a fitting to use as a return line, that way I don't have to butcher my tank up, I can get a length of rubberized fuel line to make the connections to and from the piece I'll fabricate. I have a rough sketch of what I'd like to do. I'm going to do some more research of this to see if there may be a different/better option

I live in Louisiana and there's no smog here, but I'm also planning on keeping the cats (at least the primaries) to keep my truck running within the range of having to pass a smog test in case I move to a different state at any point. I'd also like to see how reliably and safely I can run 5 or so pounds of boost with mostly stock exhaust from the manifolds to secondary cats. I'm not looking for crazy power, maybe 270 at the wheels and if I can reliably do that then maybe I'll bump it and see how it reacts.


Sent from my iPhone using Tapatalk

 

[TechFrontier]

Not exactly sure what you mean by b pipe. Your not concerned with lag?

The b pipes are the two pipes that hold the downstream O2's and the secondary cats. And honestly no I'm not worried about lag. I'm not looking to make an monster HP boost machine, just looking to test the motor to see if it can handle boost. Eventually I may come back to it and do a motor build and rerouting of exhaust piping. But for now it will need to stay somewhat uncrazy for daily driving.



Sent from my iPhone using Tapatalk

 

[BlackWidow!]

What is the cost of this do you think? I would be interested in doing it as well. It would be great if you kept the stores and websites that you buy all this from.

 

[whistler]

Going to the filler pipe for your return line seems like a good idea.
I used hard line for most of my return line but it is low pressure. From the stock tank to the new pump will take some thought.
Plus, you more than likely need a vent of some sort. Stock is a closed Systems.
I turbo charged my 92 Ford diesel . The piping was similar to what you described , it was joined after the exhaust manifolds. Only difference was the turbo was rear mounted. A very short distance to the turbo.
Plus with a diesel there is no lag due to absence of needed vacuum for the fuel system.
It was a kit made by Banks.
Thought of turbocharging my Frontier but is not legal in the organization I race in.
Still I like someone attempting this .

 

[whistler]

Here are some photos of my fuel lines.
Hardline,6AN and 8AN braided line.
All connections are AN fittings.

 

[TechFrontier]

What is the cost of this do you think? I would be interested in doing it as well. It would be great if you kept the stores and websites that you buy all this from.

so far looking at all of the supporting mods that are needed ive spent about 40 bucks on some rad fans, 15 bucks on some 10 gauge wire, i think another 10-12 bucks on electrical fittings. I already had some switches that i could use for my light bar and my rad fans so those dont count. Fuel pump and reg was ~$170, fuel lines plus fittings will be another $150 give or take. The the kit will probably total out at 2000-3000 depending on how much exhaust piping is needed and the variance of cost of R&D. Im guessing total ill be into it about 3500 plus about 500-600 for a tune. Im not planning on doing all this at one time, itll probably take me over a year to find out exactly what kind of turbo and what the best fitment for everything. Plus i dont have $4000 laying around either. Now there is an option to not buy injectors and that would save about $700, but the downside is that the stock injectors with a high pressure fuel pump and rising rate reg would mean that boosting would have to be lower than 4 pounds. any higher and itll start to lean out and youll have issues with tuning for daily driving and variable boost for when you want to go from basically no boost at idle to full boost when you stick your foot into it.

ive never attempted this on an efi motors but i know the trials of boosting when it comes to carbed motors. ive also got a few friends that have custom built scion tc turbo kits and those guys are putting 400+ to the wheels in a 2.5 turbo. i also have a pretty good knowledge of cars from when i was in auto tech in highschool and worked in a shop for a few years. its a great truck but geez, sometimes they can sure be complicated.

 

[TechFrontier]

Going to the filler pipe for your return line seems like a good idea.
I used hard line for most of my return line but it is low pressure. From the stock tank to the new pump will take some thought.
Plus, you more than likely need a vent of some sort. Stock is a closed Systems.

As long as i run the fuel pressure appropriately i shouldnt need a vent, the tank already has a vent that goes to the evap canister and then the evap goes into the throttle body. Also, in order to run a return line into the tank would be much easier and i may end up running a solid filler tube instead of just a small section

 

[shift_RUSH]

I had thought much of the magic of turbocharging came from the highly expanded/HOT exhaust gases coming out of the manifold(s). Wouldn't these gases condense/cool by a fair margin via all that piping you've outlined prior to the turbo?

I'm intrigued...and will stay tuned!

 

[TechFrontier]

I had thought much of the magic of turbocharging came from the highly expanded/HOT exhaust gases coming out of the manifold(s). Wouldn't these gases condense/cool by a fair margin via all that piping you've outlined prior to the turbo?



I'm intrigued...and will stay tuned!

The exhaust is still hot by the time it reaches the tailpipe of our trucks, maybe just not as hot. Turbo charging may be more efficient that way, but it mainly works off of the exhaust pressure and velocity to spin the turbine impeller. As you add more feet of exhaust there is likely going to be traditional turbo lag but there's a lot of people that do rear mount turbo kits on all kinds of cars and they work pretty well. My reasoning for reversing the flow back to the engine bay is to keep the turbo and charge piping in the engine bay, even if that means having a bit of lag. The only way to combat that is to buy a smaller turbo that spools faster.

Sent from my iPhone using Tapatalk