Thumper Posted February 17, 2006 Share Posted February 17, 2006 Without going with an external wastegate that is. 73turbo240z and I are having problems with boost creep. We are running the holset hy35w with an internal wastegate, megasquirt ecu, and a profec-b electronic boost controller. The turbo was designed for a 5.9l diesel running 18psi stock. We want it to run 12-18psi on a 2.8l. We have enlarged the internal wastegate hole twice its normal size and shortened the flap arm so that the flap opens further from the same amount of movement by the actuator. Any other tips either mechanical or tuning that might help us controll the boost creep? We would rather not have to upgrade to external wastegate. Any other thoughts? Thanks Quote Link to comment Share on other sites More sharing options...
AnTmanS130T Posted February 17, 2006 Share Posted February 17, 2006 You could always get rid of the profec b boost controller and run a bleeder valve. I run the profec and I have creep on my setup similar to yours. Quote Link to comment Share on other sites More sharing options...
Thumper Posted February 17, 2006 Author Share Posted February 17, 2006 Even if I bypass the ebc and hook up the lines directly to my turbo it still boost creeps. So I don't think its my ebc thanks though. Quote Link to comment Share on other sites More sharing options...
yo2001 Posted February 17, 2006 Share Posted February 17, 2006 I doubt there is anything more you can do other than what you have done. You can restrict the flow of DP which will help but you'll lose power. Or you can always run more boost. Quote Link to comment Share on other sites More sharing options...
myplasticegg Posted February 17, 2006 Share Posted February 17, 2006 keep all of your vac lines going to your turbo short. is it spiking before it creeps? Quote Link to comment Share on other sites More sharing options...
ngrimm Posted February 17, 2006 Share Posted February 17, 2006 I'm surprised you're have that problem. On my 2.3 Ford all that's been done to the Hy-35 is enlarging the hole and mine holds steady. One of our local 2.3 guys runs an HX-35 and his holds steady too. I have heard tho of some of the Turboford.org guys cutting a hole in the flange to allow the flapper arm to move even more. Could thre be a hole in the hose to the wastegate or even the actuator diaphragm? BTW if you should decide to go with an external gate, the same guy makes some internal wastgate blockoff flanges that are very nice. http://cgi.ebay.com/ebaymotors/Holset-HX-35W-HY-35W-turbo-waste-gate-blockoff-flange_W0QQcmdZViewItemQQcategoryZ33634QQitemZ8038941622QQrdZ1QQsspagenameZWDVW Quote Link to comment Share on other sites More sharing options...
oinojo Posted February 17, 2006 Share Posted February 17, 2006 take a look at this... http://atpturbo.com/root/releases/release103105.htm i used it on my honda and it held boost really well for high boost apps. Quote Link to comment Share on other sites More sharing options...
Silent Posted February 17, 2006 Share Posted February 17, 2006 three options vent the wastgate smaller downpipe convert it to external gate Quote Link to comment Share on other sites More sharing options...
Thumper Posted February 17, 2006 Author Share Posted February 17, 2006 I have put compressed air into the lines and every thing moves as it should. The lines are less than 6 inches total. 4" going from manifold to boost solenoid, then 2" going from solenoid to the actuator. Both hoses are brand new do not leak. It does not spike before it starts to creep. Ngrimm, What do you mean that they cut a hole in the flange? Thanks Quote Link to comment Share on other sites More sharing options...
dj paul Posted February 18, 2006 Share Posted February 18, 2006 to me the best choice looks like that blockoff flange. and also, how well does that thing flow? ive been looking for flow rates and pricing and i cannot find it. Quote Link to comment Share on other sites More sharing options...
Thumper Posted February 18, 2006 Author Share Posted February 18, 2006 I haven't seen a flow-chart in awhile but I know that on a 5.9l diesel they can put out 28psi-32psi. On my car it spools 12psi by 3000rpms. So its no slouch either. Remember i'm looking to keep the car internal gated so I don't want to block it off and go external. Quote Link to comment Share on other sites More sharing options...
proxlamus© Posted February 18, 2006 Share Posted February 18, 2006 Thumps.. here's a Holset turbo FAQ from Dodge.. http://dodgeram.org/tech/dsl/FAQ/turbo_faq.htm boost creep is so hard to fix.. with an internal gate.. other than porting the hole, maybe upgrading the wastegate puck.. i dunno CREEP is when the turbo produces soo much air, even with the wastegate fully open, it still creates backpressure and spools the turbo more than you wish. # Normal boost rise when set to 13 psi = shoots up to 14, then 13, 13, 13... # Spiking = shoots up to 16, then 15, 14, 13, 13, 13... # Boost creep = shoots up to 14, then 13, 13, 14, 15, 16, 17... # Spiking and boost creep = shoots up to 16, then 15, 14, 13, 14, 15, 16,17... FROM DSM.org The general solution to this problem is to portthe oxygen sensor housing, turbine housing and/or wastegate to allow themto dump more air. Otherwise minor malfunctions of the wastegate mayalso exhibit themselves as boost creep Quote Link to comment Share on other sites More sharing options...
Cody 82 ZXT Posted February 18, 2006 Share Posted February 18, 2006 take a look at this... http://atpturbo.com/root/releases/release103105.htm i used it on my honda and it held boost really well for high boost apps. Wow I really like that. Quote Link to comment Share on other sites More sharing options...
ngrimm Posted February 19, 2006 Share Posted February 19, 2006 Here is a reply from the one of the first Turboford guys that I know of to run a Holset on a 2.3. " Port the heck out of the wastegate hole and short side radius just like you would porting a head. Now it will pretty much hold any bost level I set it at and only creep 1 or so pounds of boost towards the upper rpm range." Also he cut into the flange where the flappper hits to allow it open farther. If you cut thru you can weld a cap of some sort over it. Hope that makes sense. Norm Quote Link to comment Share on other sites More sharing options...
thehelix112 Posted February 20, 2006 Share Posted February 20, 2006 Your problem is I think caused by petrol burning a lot hotter than diesel. Thus 2.8L @ 1000F is a lot more pressure than 5.9L @ whateverF. What dump-pipe are you running? You need to make one that has the wastegate dump seperate to the main turbine outlet. You can then dump it to atmosphere if you want, or plumb it back into the exhaust a little while later. Dave Quote Link to comment Share on other sites More sharing options...
Guest 73Turbo240z Posted February 20, 2006 Share Posted February 20, 2006 Alright i'm gonna jump in on this one... listing all phases of mods we've done, and the reactions they have had. All history listed is based of my personal engine/turbo setup. Phase 1: All parts installed initially, ceramic coated manifold, ceramic coated exhaust housing, 4.5" to 3.75" holset transition, to 3.75" to 3" custom fabricated transition. 83' zxt Actuator handling the boost, with a threaded end welded on for adjustment, vacuum line run from actuator to intake manifold, 4.5" approx length. Exhaust dumping @ 3" diameter under the the car near driver seat. Mild porting had been done the wastegate port prior to ceramic coating. In phase 1 we had rediculous boost creep, the longer i stayed in it, the higher the boost went. Plain and simple, it was creeping so fast that i was having to short shift to keep it off the 20psi boost cut defense we'd setup in MSnS-E. We determined more porting was needed when we unhooked the puck and left it wide open yet i was still able to build boost. Phase 2: Same as above, except we pull the exhaust housing, report the hole as big as we can go, we install a full 3" straight pipe exhaust to the tail... In phase 2 we suceeded in taming it more, what once was a wild ride of insane creep now is tamed, and manageable, i can go up to 90% throttle engagement without causing it to creep in third and fourth, pedal it in any more and it will climb. Phase 3: Here is where were getting experimental, we've halfed the length of the actuator side swingarm on Thumpers turbo, and it has an equally insane porting job as well, however he still creeps. I've loosened my actuator rod 1 turn, to where it feels like i have a micro amount of play in it, which i'm not thrilled about since that will cost me spool time if that puck is sitting open a pinch. I've yet to drive it since i'm still waiting for my new wheels to arrive. So we'll see if that solves it. Quote Link to comment Share on other sites More sharing options...
EZ-E Posted February 20, 2006 Share Posted February 20, 2006 I think I know your problem, I had the same, now that you have mentioned all that you have done. I used the same ZXT acuator, when I purchased my T3/TO4E, just because it was easier. Well I adapted the MUCH larger actuator that I had gotten with the Garret unit that I had bought almost stopped all of the creep that I had. You may want to get yourself a new actuator. With a Hallman BC, I just get a tiny bit of spike at times, maybe 2# Quote Link to comment Share on other sites More sharing options...
Guest 73Turbo240z Posted February 20, 2006 Share Posted February 20, 2006 http://www.jegs.com/webapp/wcs/stores/servlet/CategoryDisplay?catalogId=10002&storeId=10001&categoryId=27871&parentCategoryId=11911&langId=-1 i'd thought about that before, but the descriptions of the handling abilities is pretty vauge, what purpose does this dual port unit serve? Quote Link to comment Share on other sites More sharing options...
Thumper Posted February 20, 2006 Author Share Posted February 20, 2006 We measured the movement of the stock holset actuator and we measured the movement of the stock 280zx actuator and the 280zx had more of a movement. Plus even with the wastegate puck disconnected and all the way open it will still build too much boost in 4th and 5th gears. Quote Link to comment Share on other sites More sharing options...
proxlamus© Posted February 20, 2006 Share Posted February 20, 2006 the dual port will allow two vacuum sources.. The stock Nissan T3 shows a great example of this... two ports out of the turbo One port in the beginning of the compressor housing, and one right at the end of the housing.. the two different vacuum sources will be applied into the wastegate diaphram for a more "controlled" diaphram expansion and contraction.. my educated assumption anyway.. http://www.atpturbo.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=ATP-FTG-010&Category_Code=BCS A boost pressure source near the compressor housing is critical for proper boost control, however, removing the compressor housing from the turbo to tap it for a pressure signal fitting can be a real chore...especially when the turbo is already mounted to the engine. Each QuickTap kit includes all parts necessary to easily create a reliable boost pressure port on the first silicone connector out of the turbo compressor outlet. Our QuickTap kit features 100% of the functionality and reliability of a fitting on the compressor housing without the hassle of drilling and tapping the housing itself. Quote Link to comment Share on other sites More sharing options...
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