# factory boost controllers... **URL:** \ **Category:** NYSpeed Automotive\ **Created:** [April 18, 2006, 5:16am UTC](https://forums.speedlife.net/t/factory-boost-controllers/10929 "2006-04-18T05:16:58Z")\ **Posts on this page:** 14\ **Page:** 1
**Author:** ![newman](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/newman/32/7569_2.png) [@newman](https://forums.speedlife.net/u/newman)\ **Post date:** [April 18, 2006, 5:16am UTC](https://forums.speedlife.net/t/factory-boost-controllers/10929/1 "2006-04-18T05:16:58Z")
So… i bought a few things for the sti: Cobb access port Turboback Exhaust First i installed the cobb access port and drove it for a week. Everything seemed good, made boost fine. Then i installed my exhaust. When I installed my exhaust i also ported my wastegate. Now i am only boosting 10PSI. This makes sense to me, because the factory boost controller would still cycle the WG the same, but since it flows much more, it would boost much less. I was informed that it could be a leaking up-pipe gasket (i didn’t replace it the first time i pulled the turbine) so i replaced that (a fucking 4 hour job) and it still behaves exactly the same. Am I correct in thinking that the factory (and nearly all) boost controllers don’t even reference the target boost value (except in certain boost controllers where it leaves it closed to a set PSI) they simply cycle at a certain frequency (duty cycle) and amplitude (gain) and the actual boost pressure is dependant on engine flow (intake and exhaust tract, including WG) It makes sense to me. Am I on target? ---
**Author:** ![zwarbyt](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/zwarbyt/32/7623_2.png) [@zwarbyt](https://forums.speedlife.net/u/zwarbyt)\ **Post date:** [April 18, 2006, 5:25am UTC](https://forums.speedlife.net/t/factory-boost-controllers/10929/2 "2006-04-18T05:25:19Z")
use a grainger valve, problem solved ---
**Author:** ![newman](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/newman/32/7569_2.png) [@newman](https://forums.speedlife.net/u/newman)\ **Post date:** [April 18, 2006, 5:28am UTC](https://forums.speedlife.net/t/factory-boost-controllers/10929/3 "2006-04-18T05:28:38Z")
mike can modify the duty cycle on my factory boost controller with the accessport, that’s not a problem, but do you guys think that this is the reason i am not seeing full boost? Or do you think i left something disconnected… ---
**Author:** ![boardjnky4](https://avatars.discourse-cdn.com/v4/letter/b/96bed5/32.png) [@boardjnky4](https://forums.speedlife.net/u/boardjnky4)\ **Post date:** [April 18, 2006, 6:15am UTC](https://forums.speedlife.net/t/factory-boost-controllers/10929/4 "2006-04-18T06:15:27Z")
i see what ur saying about the porting. to me you sound correct. I couldnt be positive but i doubt the computer monitors ur boost pressure. The wastegate runs off of vaccum and thats probably to only thing monitored by the ecu. This leaves me to assume that you are correct. ---
**Author:** ![Inn-Tune](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/inn-tune/32/7588_2.png) [@Inn-Tune](https://forums.speedlife.net/u/Inn-Tune)\ **Post date:** [April 18, 2006, 6:19am UTC](https://forums.speedlife.net/t/factory-boost-controllers/10929/5 "2006-04-18T06:19:52Z")
The AccessPORT does reference MAP readings to help it hit boost targets, but not as aggressively as aftermarket EBCs, so the duty cycles need to be close. When I tune your car it will take care of this. ---
**Author:** ![newman](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/newman/32/7569_2.png) [@newman](https://forums.speedlife.net/u/newman)\ **Post date:** [April 18, 2006, 6:28am UTC](https://forums.speedlife.net/t/factory-boost-controllers/10929/6 "2006-04-18T06:28:17Z")
i think that even aftermarket EBC’s don’t use a pressure reference… My greddy E-01 didn’t even have an input for target boost, just duty and gain. It had an auto mode that was meant to learn the car, but it never worked properly. The only thing that you entered in PSI was the start boost value, which held the WG closed (no modulation) until a set PSI. Frankly, I would be surprised if the factory boost control circuit based anything on the MAP, save for an overboost protection control, and a start boost value (but i doubt it is that sophisticated). ---
**Author:** ![JaysGreenLX](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/jaysgreenlx/32/7321_2.png) [@JaysGreenLX](https://forums.speedlife.net/u/JaysGreenLX)\ **Post date:** [April 18, 2006, 7:07am UTC](https://forums.speedlife.net/t/factory-boost-controllers/10929/7 "2006-04-18T07:07:11Z")
Newman did you buy a new exhaust or the one from the guy who was selling a used one here? ---
**Author:** ![newman](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/newman/32/7569_2.png) [@newman](https://forums.speedlife.net/u/newman)\ **Post date:** [April 18, 2006, 7:20am UTC](https://forums.speedlife.net/t/factory-boost-controllers/10929/8 "2006-04-18T07:20:44Z")
i got a JIC magic SST system. It fit poorly, but i got the whole stainless/titanium turboback with cast bellmouth for 800 new off of ebay from a private seller. I couldn’t find it anywhere else for under 1100. ---
**Author:** ![newman](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/newman/32/7569_2.png) [@newman](https://forums.speedlife.net/u/newman)\ **Post date:** [April 18, 2006, 7:21am UTC](https://forums.speedlife.net/t/factory-boost-controllers/10929/9 "2006-04-18T07:21:06Z")
and where is zerodaze on this. ---
**Author:** ![jrex](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/jrex/32/7232_2.png) [@jrex](https://forums.speedlife.net/u/jrex)\ **Post date:** [April 18, 2006, 8:42am UTC](https://forums.speedlife.net/t/factory-boost-controllers/10929/10 "2006-04-18T08:42:58Z")
If anything I think you should be seeing more than factory boost unless something with the wastegate is borked, or you have a gasket leak…Did you replace the manifold to head gaskets? I had a similar issue with my old car and it was uppipe gaskets. ---
**Author:** ![Zong](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/zong/32/7580_2.png) [@Zong](https://forums.speedlife.net/u/Zong)\ **Post date:** [April 18, 2006, 9:51am UTC](https://forums.speedlife.net/t/factory-boost-controllers/10929/11 "2006-04-18T09:51:25Z")
TurboSX TBE’s are under 1100 but not for titanium. Is your downpipe catted? ---
**Author:** ![newman](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/newman/32/7569_2.png) [@newman](https://forums.speedlife.net/u/newman)\ **Post date:** [April 18, 2006, 9:53am UTC](https://forums.speedlife.net/t/factory-boost-controllers/10929/12 "2006-04-18T09:53:34Z")
> [@azndc5er](#): > > TurboSX TBE’s are under 1100 but not for titanium. Is your downpipe catted? i meant under 1100 for the JIC system, it’s not full titanium, just partial. It’s a relatively nice unit. And update on the boost… I disconnected the wastegate and it went to 18 no problem. It would have kept going but i let off… ---
**Author:** ![Zer0DazE](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/zer0daze/32/7624_2.png) [@Zer0DazE](https://forums.speedlife.net/u/Zer0DazE)\ **Post date:** [April 27, 2006, 4:59am UTC](https://forums.speedlife.net/t/factory-boost-controllers/10929/13 "2006-04-27T04:59:05Z")
newman, it is controlled by the ecu, and i will bet dollars to doughnuts it references the MAP sensor for boost control. i know that my car does… its all part of the ecu code. ---
**Author:** ![99\_civic\_si](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/99_civic_si/32/7319_2.png) [@99\_civic\_si](https://forums.speedlife.net/u/99_civic_si)\ **Post date:** [April 27, 2006, 8:57am UTC](https://forums.speedlife.net/t/factory-boost-controllers/10929/14 "2006-04-27T08:57:49Z")
Yeah, I don’t think the problem lies within duty cycle. I ported the WG on my bros FD and all it did was help prevent spikes and surges from the stocker being uber small. I don’t recall if we had to adjust duty cycle though, but his car is finicky as hell when you go outside a ±5% range within his duty cycle. Still I would think your not seeing full boost due to something else. You don’t have a leak now in your wastegate from too big a port do you? edit: or what jon said.