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Avant Nate
01-16-2011, 09:09 PM
I just wanted to know how dangerous it would be to run a larger turbo, say a 2871r at lower boost until rods could be done, if ever. Besides a slower onset of boost, is there any other drawbacks?

Turbo Nerd
01-16-2011, 09:43 PM
I'm running 2871 on a giac ecux K04 tune, my turbo isn't even working hard I'm sure its not efficient but I don't step on it everywhere. I bought the car like this and he's had this setup for about a year.

Turbo Nerd
01-16-2011, 09:50 PM
Also there's a lot of people running a 2871 ranging psi from 15-24 on stock motor so you will be alright. When I bought the car the original owner asked if he could keep the boost gauge and I said sure but it was pushing 10 psi before I bought it with a small boost leak. I fixed the boost leak and I upped the turbo efficiency from 80% to 100% via lemmiwinks. I ordered my Podi boost gauge and it should be here in a couple days so not sure how much boost I'm running. Also my car has supertech valve springs and retainers so I should be able to go to 8K RPM w/o any issues, but my tune isn't allowing me to go past 7K which sucks. I need a bigger intercooler (have a ebay one right now) and many people said that it's too small for this turbo, so I will be purchasing a treadstone (link below) and a get custom tune from VAST pretty soon here.

http://www.treadstoneperformance.com/product.phtml?p=29&cat_key=63&prodname=TR8+Intercooler

Avant Nate
01-16-2011, 10:17 PM
I'll be running it on a Ctapp 630cc tune, was going to use precision intercooler, control boost with manual. Original plan was GT28rs on t3 psi mani, externally wastegated. I'm piecing stuff together right now

dowsett6
01-17-2011, 01:18 PM
I was running my t3/t40E setup on 12lbs and it was fine. It was the 630cc tune as well.

Dan[FN]6262
01-17-2011, 01:31 PM
I ran my 2871R on a completely stock engine, and I had it so that it would spike to 25-26psi and hold 22psi at redline. Never had a problem with it. It was on a Revo tune, since I'm a B6.

.Mad Hatter.
01-17-2011, 02:44 PM
You should be fine; although AEB and on a 415cc tune I am running 19psi on a completely stock motor. 12psi and you would be golden I think.

ZimbutheMonkey
01-17-2011, 03:32 PM
If you're an AEB at least make sure that you have a wideband Air/Fuel gauge. Innovate sells a complete setup for $230 and it's worth every penny to know that I'm not running lean.

One thing to note though, I find that on my GTRS elim setup, running low boost actually results in leaner running conditions than higher boost. Whether or not that's a result of the manifold referenced fuel pressure not picking up on account of the lower boost or the MAF scaling not giving the ECU the go ahead to open the injectors more I'm not sure. However it'd be a good idea to keep tabs on things if you're not running the boost that your programming is intended for.

ZimbutheMonkey
01-17-2011, 03:38 PM
I was running my t3/t40E setup on 12lbs and it was fine. It was the 630cc tune as well.

Any idea of how much power it was making at that boost level? I've got a 60-1 I'll be putting in and I'm curious as to what low boost running is like.

dowsett6
01-17-2011, 05:05 PM
Any idea of how much power it was making at that boost level? I've got a 60-1 I'll be putting in and I'm curious as to what low boost running is like.

Not a clue. But it keeps up with my friends S4 that is revo tuned, with piggies and an exhaust dump before the mufflers. We are basically next to each other whenever we do pulls, it just depends on who jumps the gun on the peddle.

ricekikr
01-17-2011, 05:14 PM
I was running my t3/t40E setup on 12lbs and it was fine. It was the 630cc tune as well.

I also have t3/t4 50trim, running 22psi for a couple of months, so far no probs. 630cc + self-tune. My friend runs an evo turbo (forgot which) 25psi daily, no problems with rods either. Both AEB.

adam.wilber
01-17-2011, 06:00 PM
I've got an AWM and I'm wondering the same thing. If I can push more boost with a bigger turbo without dropping the cash on pistons/rods then it'll be done for this summer lol.

Dan[FN]6262
01-17-2011, 06:12 PM
pics of the 60-1

ZimbutheMonkey
01-17-2011, 09:06 PM
Right here http://www.audizine.com/forum/showthread.php/406175-Do-I-smell-a-60-1-build-(pics)

SR-71
01-18-2011, 08:48 AM
I've got an AWM and I'm wondering the same thing. If I can push more boost with a bigger turbo without dropping the cash on pistons/rods then it'll be done for this summer lol.

Make sure you get at least a 630cc tune. I'm running a 50trim @ 20psi with 630 tune from Jeff Atwood and stock rods are holding up just fine.

dcampana
01-18-2011, 09:21 AM
I am on a 2871 elim, with 440cc and 25 psi, no issues for about 15k. AWM

grillhands
01-18-2011, 05:39 PM
I was running my t3/t40E setup on 12lbs and it was fine. It was the 630cc tune as well.

12lbs keeping up with a chipped s4? What's the trim on that t3/t04e? It has to be a 57 or a 60.

I run 22lbs all day and i'm not sure if i can keep up with an s4.

.Mad Hatter.
01-18-2011, 05:48 PM
A chipped S4 is worth 300 at the crank isn't it? Most healthy elim. setups should be able to hang with one, if not beat it.

grillhands
01-18-2011, 05:55 PM
A chipped S4 is worth 300 at the crank isn't it? Most healthy elim. setups should be able to hang with one, if not beat it.

Yeah, but not at 12lbs. When i had my gt2x running 25lbs, i raced my friend mazadspeed 3 that had a k04, front mount, full exhaust and a cobb access port. From a roll or a dig, i had him by maybe a half a car. When i put my t3/t04e in and ran it at 15lbs because i didn't have a wideband, he absolutely destroyed me in every which way. That's why i'm a little curious to know what trim he is running.

The t3/t04e is massive compared to the gt2x so after i received my whoopin, i decided to bump the boost to around 20lbs and watch the a/f.

SR-71
01-18-2011, 05:57 PM
Not a clue. But it keeps up with my friends S4 that is revo tuned, with piggies and an exhaust dump before the mufflers. We are basically next to each other whenever we do pulls, it just depends on who jumps the gun on the peddle.


You got a 60trim at around 12 lbs and it keeps up with an S4? I find that really hard to believe but hey, anything can happen.

grillhands
01-18-2011, 06:03 PM
You got a 60trim at around 12 lbs and it keeps up with an S4? I find that really hard to believe but hey, anything can happen.

S4 has a shit load of torque that takes them off the line really stupid fast.

discontained
01-18-2011, 06:58 PM
Im running a T04e / atp mani. everything else is running on stock ecu/ injectors (was selling the car and friend wanted 630cc injec) etc. Im only running 8-12lbs. I did mess with the fueling and AEM Wideband stuff.

I still do have the unitronics 630cc tune / seperate ecu when I do get my injectors. Nothing else tho car runs fine no problems or anything besides a occasional backfire/fireball upon using the tipmode on shifts.

grillhands
01-18-2011, 07:08 PM
Im running a T04e / atp mani. everything else is running on stock ecu/ injectors (was selling the car and friend wanted 630cc injec) etc. Im only running 8-12lbs. I did mess with the fueling and AEM Wideband stuff.

I still do have the unitronics 630cc tune / seperate ecu when I do get my injectors. Nothing else tho car runs fine no problems or anything besides a occasional backfire/fireball upon using the tipmode on shifts.

You are running a straight to4e? That must take forever to spool and i didnt know that atp made a t4 manifold.

I've just noticed that you are on stock ecu. You really need to pay close attention to your wideband to make sure you keep it under 12a/f

discontained
01-18-2011, 08:04 PM
Everythings fine. I watch it and dont really stomp it up to the redline. It full spools about 3800rpm on a good day usually its around 4k. I dont plan on beating on it while its in its current state lol. Last thing I want to do is lean out and explode.

Its a ATP T3 mani btw.

ZimbutheMonkey
01-18-2011, 08:13 PM
A chipped S4 is worth 300 at the crank isn't it? Most healthy elim. setups should be able to hang with one, if not beat it.

Back when I had my Mazdaspeed K04 hybrid on a tip transmission I raced a buddy of mine who had a chipped S4 on a roll from about 80 km/hr and we were dead even. That was putting out about the MAF readings that my GTRS elim put out at 15 PSI. Ever since I did the 5 speed swap and the elim I figure I could probably take a stage 2 S4. One thing to note is that I'm FWD though so I'm lighter and put a little more power to the ground than an AWD. So take that for whatever it's worth.

grillhands
01-18-2011, 08:45 PM
The mazdaspeeds 3s are pretty quick cars. However, my buddy has 20*k miles or so and already had to replace the trans for about 5gs!

dowsett6
01-18-2011, 09:28 PM
12lbs keeping up with a chipped s4? What's the trim on that t3/t04e? It has to be a 57 or a 60.

I run 22lbs all day and i'm not sure if i can keep up with an s4.

Its a 57trim with a 0.63AR. and yes 12lbs and I'm next to the S4, not from a dig, but we have done lots from 30km/h and up.



You got a 60trim at around 12 lbs and it keeps up with an S4? I find that really hard to believe but hey, anything can happen.

Yep, full straight flow 3" exhaust, no cat, huge fmic, 90mm Maf, 630cc @3bar, pcv deleted, emissions deleted, bov, intake mani spacer, efk, on maestro. I think that's the main stuff.



S4 has a shit load of torque that takes them off the line really stupid fast.

And they sound amazing dumped before the mufflers.

dowsett6
01-18-2011, 09:35 PM
A chipped S4 is worth 300 at the crank isn't it? Most healthy elim. setups should be able to hang with one, if not beat it.

That is what I thought too. And doing HP calculators from drag speeds they estimate my crank hp is ~300 - 350

ZimbutheMonkey
01-18-2011, 09:43 PM
So dowsett, are you estimating 300 CHP at 12 PSI or is it higher now? By the sounds of it, your setup is going to be very similar to mine once I install the 60-1. If that's the case at 12 PSI, I'm looking forward to what this thing will put out at 18-21 PSI. Also, do you have any acceleration footage of your car? If not, post some up. There is very little of T3/T4 setups on the longitudinal platforms.

20vpower
01-18-2011, 10:09 PM
I have a t3t4e 50 trim .63. I run 630 ctapp with lightning maf. Just put my full 3" exhaust on and run only 12psi (wg spring) haven't really gone past 15psi yet. I'm still on stock block. There was a guy on here running same setup but uni 440 tune and made ~250whp on 12 psi And 352 whp on 24psi I think this was 93 oct

ZimbutheMonkey
01-18-2011, 10:19 PM
Yeah, that sounds about right. As I've said before, these T3/T4's seem to be really underrated turbos. For the cost vis a vis a GT3071 or 76 you get a lot of bang for the buck. Better still if you can find a used one.

20vpower
01-18-2011, 11:20 PM
That was my main reason for going t series. Got mine for 610 shipped brand new.

grillhands
01-19-2011, 07:50 AM
There must be a big difference between the 46trim and the 50trim because mine doesn't feel like 300awhp. If i had to guess i would think it would be around the 260-280awhp. I know the 46trimt3/t04e pushes 41lb/min and i'm pretty sure the 50 trim is 46-47lb/min. 034motorsports sells a t3/t04e 45trim and that is good for 350hp and i'm guessing that's at the crank. When i put my rods in i'm going to sell my turbo to my buddy and look for a 57trim or a gt30r. I will probably get the 57 because there cheaper and rebuildable.

viceprp
01-19-2011, 08:52 AM
My current setup is listed below and was dead set on getting a k04 when I first bought the car. Then came the elim. kit and I was thrilled with the power on a stock block. Then after talking to Q @ RAI, I then thought I would put new rods in a push the car a bit further bc I constantly read "I want more power" from us B5 guys. The idea jumped to do a 50 trim and push ~330whp for a daily. In conclusion, the motor is built and planning on slapping a gt3076 with meth and hopefully have a ~380whp DD.

20vpower
01-19-2011, 12:38 PM
To OP, why do you want to run external WG? Just makes it so another piece in your exhaust to crack. Internal makes routing exhaust down pipe much easier. If you're dead set on it, I have wg adapter and dump tube for the ATP mani that I'm not using anymore.

Dan[FN]6262
01-19-2011, 12:56 PM
my turbo's a journal bearing turbo, and I love it.