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xrtdac
08-01-2004, 01:17 AM
Ok so with the stock head and stock intake manifold and 3" intake I was holding steady boost at 15psi and 30psi. Now I have added about a foot and a half of 3" to the downpipie where the cat back starts (blew out old felx so added some 3" in its place). Next I ported the exhaust manifold a little further to aid in the flow from the new head and intake manifold. In the porting process found a ab that was in the exhaust manifold by where the gate went on so I got that off figuring it was slowing exhaust flow to the turbo. Things were ok prior to putting on the new head and intake manifold. With the new head I was pulling a peak powerband from 5500 to 8000 in comparison to the stock on having a 5k-6k powerband (see dyno below). The dyno below doesn;t show the chart out ot 8K.
http://www.xratedcc.com/gallery/albums/Random/ty3.sized.jpg

Now with the new head we ran into some creeping issues when we were taking it out to 8K. goes to 17PSI then crept to 20. also ran the boost control from the wastegate alone at a 1bar spring and it got to 15psi and crept to 20 again. Now we swapped in the Victor X intake manifold and we ended up getting a flatter torque curve and a pwoerband looking like a freekin GSR meaning a simple hillclimb the whole way up. Still boost creeping. 1 bar to 20psi.

Keep in mind also now with the new head and intake manifold the fuel conditions are rich and falling below 10.0 at some points. BUT we are getting sky high EGT's.

So I have had several theories kicking around right now about why it is doing this.
1.) boost leak somewhere and it is big so I can' hear it easily due to no high pitch in it.
2.) New head and intake manifold flow way more than the drag manifold and old .48 exhaust housing can handle thus creating back pressure pre-turbo in the manifold. (PS I know the wastegate is opening. its not related to boost control cause we rana manual boost controller and it did the creep and then ran the control directly from the gate and it still crept.)
3.) blow by in the motor is causing some screwed up things to happen, who knows what.
4.) injector is misfiring and causing a timing pull fromteh ecu. NO CEL's though.

ANYONE ELSE HAVE THeOrIES OR CAN VALIDATE SOME OF MY THOUGHTS???????

THE SET-up:

http://www.xratedcc.com/gallery/albums/tylermemberpics/PICT0784.jpg

http://www.xratedcc.com/gallery/albums/tylermemberpics/PICT0786.jpg

ENGINE:
B18B1 (417.2HP, 409ft-lbs SAE to the wheels [stock head and stock intake manifold used for these numbers]. 11.6 @ 129mph 1/4ET)

Wiseco Pistons 83mm 8.5:1 compression
Eagle H Beam rods
Golden Eagle sleeves
ARP bolts and head studs
Crane turbo Cams
Webcams dual valve springs
titanium retainers
stainless seats
SI .5MM oversized valves (swirl polished)
Mild porting
Victor X intake manifold
Cometic Head Gasket
Hondata Intake Manifold gasket
Polished crank
Balanced motor
Random Tech *ONE OFF* 3" stainless cat-back
5 bolt 2.5" to 3" downpipe.
ACT 2600 6 puck clutch
Tenzo-R Valve Cover Breather
B&M fuel pressure gauge (filter mounted)
AEM fuel pressure regulator
AEM high flow fuel Rail
AEM under-drive pulley (PS)
Taylor 409 10.4MM spiro-pro race ignition wires
Turbonetics 60-1 Turbo (S cover .70, .48 T3 exhaust)
3 Bar Map Sensor
RC 660CC Injectors
Hondata S100 w/boost
DRAG turbo manifold (ported & matched)
Tial Wastegate
HKS SSQ BOV
Elite manual boost controller
Walbro high flow fuel pump
Streamline Radiator Fan
PTE AS1098 FMIC
Skunk2 cam gears
K&N Intake Air filter (4" intake pipe)
Weopon-R throttle Rotor

xrtdac
08-01-2004, 02:43 AM
PS: Forgot to ADD. We also changed the first charge pipe on the hot side from a 2" to a 2.25" pipe. the old set up had a 2.25" outlet on the s cover to a 2" pipe back to a 2.25" pipe to the 2.5" intercooler.

Pushit2.0
08-02-2004, 10:13 AM
Its been said befor, its possible the .48A/R could cause to much back pressure with all the new flow, so the turbo creeps. A .63A/R exaust side should fix the problem and get you more whp. Its not even another $150.

~John

xrtdac
08-02-2004, 10:27 PM
found out some other interesting info. could the obscene rich condition be causing fuel to get by and detonate more into the manifold thus creating more pressure and pushing teh creep along? that was one theory.

also the drag manifold evidently has amjor creeping issue when a lot of heavy mods are done behind it.

Pushit2.0
08-03-2004, 09:04 AM
I have noticed with my car a really rich setting will cause less boost, But I still say you could try a .63A/R anyways. If thats not the problem then a differnt manifold would be in order.

~John

JET
08-03-2004, 09:35 AM
Well, it seems to be pretty common with manifold mounted wastegates. Barton and Mo both have boost creep problems and they also have manifold mounted wastegates. It seems to be a pattern.

Shane@DBPerformance
08-03-2004, 09:39 AM
Mo's, Brians and Tylers are all single runner mounted also. Even though I never had a problem with it setup that way with multiple turbos, Mara's didn't have a creep problem and Mo didn't have a problem until this latest 3561 turbo, which is the exact same one Brian has. Going off the collecter would be better than just off a single runner.

SlowWhite
08-03-2004, 09:44 AM
Well see how bad my boost creep is now that I've routed my dump tube back into my exhaust.


I really hope all I hear now is turbo spool :woowoo:

Pushit2.0
08-03-2004, 04:02 PM
I have the same one runner mounted waistgate, no creep for me. And brian, it sounded like an exaust leek the one time I road in your car, but I hope that fixes it for you.

~John

JET
08-03-2004, 04:45 PM
And you don't have as big of a turbo as these other guys. Maybe not enough air can flow out of the wastegate since the bigger turbo's will be pushing more air through than the smaller turbo's. Having air go out of mainly one cylinder might not be enough to hold the boost.