GSX_TC's Galant VR4 Build Thread #550/2000 (Samara)

[GSTwithPSI]

Quoting GSX_TC:
Yeah on that Dyno at TX2k it didn't have enough load and wasn't letting the car creep to 16 pounds like it did on the street and D3's Dyno. It only peaked at 10 pounds on that Dyno. I was pissed. And I can't turn the boost up because I'm already out of pump. So I'll be most likely upgrading wastgates and routing the wg dump tube back in the down pipe to help solve the creep issue, then go ahead and do the dual 255's and 2150's.



If boost creep was the issue, routing the dump pipe back into the exhaust would only add more restriction to the system, thereby worsening the condition. And, typically, boost creep causes a higher than desired boost level, not lower. Swapping in a larger wastegate may help, but honestly, I don't think boost creep is your issue. You're damn near running no exhaust at all, so boost creep doesn't really even seem viable. Adding a full exhaust system after the turbo would be the only modification to the exhaust system that would actually help.

I would take a close look at whatever you are using for boost control. Have you considered using your ECMlink setup to control boost? Whatever you do, I agree with Mark. Modifying your dump tube and wastegate seems kinda pointless. You have to be realistic, and know there will be issues with a new tune and setup. Give it some time, and you'll get the kinks worked out.

 

[4thStroke]

You won't have creep issues if you ran the turbo at a practical boost pressure. Adding a larger gate now when you plan on going with a larger fuel systems will be nothing but a waste of money.

 

[turbowop]

Quoting GSTwithPSI:
Whatever you do, I agree with Mark.



/ubbthreads/images/graemlins/h5.gif

 

[diambo4life]

Is the boost signal been run directly to the gate or do you have an MBC inline at its lowest setting to achieve minimum boost? Where are you sourcing the boost signal? Pre or post fmic?

 

[GSX_TC]

Boost is off the waste gate and the boost controller is set to zero at the moment. Hopefully getting dual pumps and 2150's and more boost will cure all this up.

 

[curtis]

OK hate to sound like a broken record but the dual pump idea is BS. Perfect world at 14.3 volts the pumps flow the exact same numbers but this isn't always the case. Probably 2 out of a 10000 will flow the exact same numbers and pressures. Your always going to have one backflowing against the other one. Just as soon as a check valve in one fails your screwed. In my opinion the twin pumps is like putting a bandaid on a sucking chest womb and then putting another bandaid over the first. Buy one real pump and be done with it. A1000 or a SX and call it good.

If you don't want to sump a tank for an external pump run a big in tank wfo to a surge tank then a big pump from that to supply the engine.

 

[GSX_TC]

If the tuner and the engine builder suggest dual in tank 255's than i dont see why not. Cory Bowers was was suggesting i use a hobbs switch on the pump setup so that way the second one doesnt come on until a certain boost level. i do need to adress the boost creep issue though still because, when i dyno'd at TX2K most i got was 10 pounds due to the light load, but then on the street it creeps to 16 pounds. so im prob gonna change out that wastgate the same time i re-do the fuel system too. this turbo is not even in its range yet, so thats why its not behaving the way i want it to yet on such low boost. raced a buddy of mine from LA the other night and he pulled on me, granted he was on 28 pounds of boost and what he calls "an unfinished tune" and still maganged to pull past me. seems like i can barealy hang with him with im making that 16 psi but when i change gears to make it again it takes forever to come back.

I really dont wanna have to put a surge tank at this point, or at least not yet though because i still need to pay a few things off first and start saving up for our trip to the shootout this year. so if this dual pump idea works out and i hit the power level i want and i enjoy the car on the street as well then it'll stay that way for a while. but for now, i need to start saving up because the shootout is in 151 more days. =)

 

[turbowop]

Dude. You DO NOT need a different wastegate! Just set up your fuel system and run higher boost like the turbo wants. The creep issue will fix itself.

Or don't listen to us and feel free to waste more money. It's not like your priorities have made much sense to us the past year or so anyway. /ubbthreads/images/graemlins/uhh.gif

 

[Gizmovr4]

The reason I don't run dual pump setups - if one fails car will still run correctly till you get on boost !! Once you go WOT and one of the pump fails you will likely loose the engine by running it lean. Many of the cars running dual pumps did so because there were no single pumps available to deliver enough fuel for the application. This is no longer the case - there are plenty of single pumps available now for most hp applications. Simplify the system and eliminate points of failure use a single pump!

As for the boost creep- once you run 25+ pounds of boost the car will power thru it and you will not feel it. Boost creep will happen regardless of the waste gate used at that low boost pressure....

Update the fuel system - with whatever system you choose - either a single or dual pump system will produce enough volume. I explained why I would go single but either will work! Then have it retuned. The wastegate can always be replaced later-unless you believe the gate not to be holding - which could explain the lazy boost hp curve !

 

[mitsuturbo]

Quoting turbowop:
Dude. You DO NOT need a different wastegate! Just set up your fuel system and run higher boost like the turbo wants. The creep issue will fix itself.

Or don't listen to us and feel free to waste more money. It's not like your priorities have made much sense to us the past year or so anyway. /ubbthreads/images/graemlins/uhh.gif



Mark, to be fair i do believe he's running a sub $100 EBAY wastegate with that shiny new $1900 turbocharger. I would suggest he replace it as well. /ubbthreads/images/graemlins/dunno.gif A quality part, such as a Tial MV series, or even a Turbosmart would probably be a good way to go.

"I need Dual pumps and 2150's" ? Seems like an excuse. Plenty of guys have made WELL over 400awhp on a 255 and 950-1150cc injectors. I'm pretty sure there are also now 400lph drop in pumps available. I have a 340lph myself, and i'm sure it will have no problem supporting over 400whp.

 

[turbowop]

Replacing a sub-par part with one of higher quality is a good idea, I agree. My point is just that the wastegate isn't the issue.

 

[GSX_TC]

Do y'all think a Walboro 450 will be adequate for over 600+ though? Because that's what I'm stuck on, either dual 255's or a single 450. And saying I need 2150's and a bigger pump is not an excuse, if the tuner says it's out of pump then it's out of pump. And the injectors weren't all the way maxed out, they were at 81% IDC. So yeah, it's time for more fuel, not an excuse. Lol

 

[GSX_TC]

Well I agree with you mark, I hope turning up the boost later on will solve the creep issue as it will actually be controlled by a MBC as opposed to just off the gate like how it is now. But yes the WG I'm using is an EMusa one so I would like to replace that with a Tial. Then the car won't have anymore cheap parts on it that question performance.

 

[LIV4PSI]

It still has an Ebay manifold too doesn't it?

On a related note, I have a spare Walbro 255 pump I could sell you for cheap.

 

[mitsuturbo]

Here's the thing, GSX_TC... your car looks pretty good. You've got a lot of money into it. I don't think i'm alone in thinking that we all want to see it put down some nice respectable numbers, whether it be timeslips, dyno charts, or whatever. Please don't go thinking i'm trying to "bash" on your ride. However, you may want to consider having someone else take a look at your tuning, and your fuel setup... get a 2nd opinion. There's no harm in that. Right?

A new wastegate should be a priority, of course. Who knows if that thing you have is operating reliably at this point, and a good boost controller is pretty much mandatory. These two things together will make a HUGE difference. Also, have you considered tuning for some pump gas as well? 30% less fuel is required, so your IDC would drop considerably. I'm sure you could safely tune 400whp on 92 with what you have.

You've really kind of put yourself out there with all the pride you've taken in this car. You've posted more photos than most of the users have here, combined. You've put together a car that LOOKS the part. I just hope it comes together and actually performs as well as it looks. Good luck with it.

Edit: i just had a thought... any tuner that would take the time to tune "around" boost that creeps from 10 to 16psi isn't really going about things properly and if you've paid them, i honestly think you've wasted your hard earned money. It would have been better spent getting whatever you need to achieve a flatline boost response once the turbo spools so that you can get a more adequate and reliable tune going on. They should have told you to, or helped you to fix the boost issues before trying to tune it for any sort of power.

 

[GSX_TC]

Quoting LIV4PSI:
It still has an Ebay manifold too doesn't it?

On a related note, I have a spare Walbro 255 pump I could sell you for cheap.



Not sure, but I don't think it's eBay. It's just some ram horn.

 

[LIV4PSI]

It's looks like an OBX which is China knockoff territory. Also, I should have the antenna bracket you asked about. I will text you later

 

[Jesus_Negros]

Ramhorn by who?
I would take mitsuturbo advice on getting a second opinion on the tune.

We all have been here looking at your progress since the day you got your car. You may think some are bashing or being harsh but mostly just straight up honesty. We all want to see you meet your goals for this car. It's a beautiful car and you're actually making progress on the car unlike 80% of the GVR's out there. Plus, in this thread thats almost 30 pages long have you seen anyone try to give you advice that's not to the benefit of Samara?

 

[theevozero]

Its not out of pump. A single Walbro will take you to 500hp on e85. You have something else going on.

Also, your boost issue kinda explains your weak torque curve. It makes max torque when max boost hits, then starts making power once it starts creeping.

 

[Gizmovr4]

Mike, as for the walbro 450 - that's the pump in my gray car - that car has 1650cc injectors . It made 556awhp at 30psi of boost fp3052 on pump E85. On that setup the car was not out of injector or pump and very streetable. We decided it was enough power for the street and didn't want to push any further. Will the walbro 450 be enough for your setup? Depends on how far you want to push it !! Keep in mind anything over 550awhp+++ and you need to seriously think of all the other components in your build and if they are up to the task. (Transmission, transfer case, rear, axles, ect.)

I like reading your posts and seeing the progression ! The car has come a long way !!