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recently got a gizzmo boost controller installed on a R32 with rb20det and stock turbo, wanna run on 12psi and dont really know how to deal with the duty cycle on the boost control....what do people normally set on?

on my apexi, i have the boost and duty cycle done and was on the dyno, that was for forth gear..which is where the base should be..

would get best results on a dyno..

on my apexi i can do adjustments for each gear , so you add say +10 at a time and see how it responds, best to ramp it up with the duty than have just a flat line.

Edited by SliverS2

A slight spike is normal, better off hopping on a the motorway and pushing it in 3rd or 4th. 1st and 2nd are not great gears to be determining duty cycles.

However, a slight spike is good to bring boost to the desired boost levels quicker. I used to have my old shtbox spike to 1.4bar and settle at 1.3bar.

like i said 4th is the base, wind it up for the other gears, i have 90% for my duty upto 3000rpm, it brings it on like a cut snake.... thats for a big turbo

Edited by SliverS2

when is it hitting full boost? is that 12.75 holding or was it a spike? what gear?

i think it was just a spike....i was on the 3rd gear and it rised up to 12.75psi....but after that i tried again...it was holding on 10.8

like i said 4th is the base, wind it up for the other gears, i have 90% for my duty upto 3000rpm, it brings it on like a cut snake.... thats for a big turbo

so should i use the 4th gear to test it? coz in the 1st or 2nd gear.....they rev quite fast....but i dont think they rise more than 6 or 7psi...

I have a GFB electronic boost controller, Which from my understanding is very similar to yours. I ended up taking it to tunehouse to get it tuned. Its not something you want to muck around with if your not sure about it.

Need to put load on the engine to set the pressure right (duty cycle), 1st and 2nd are completely unsuitable. On a dyno, 4th gear would be used, on a flat road 3rd gear minimum, or better yet to put load on an engine 3rd gear uphill.

Once duty cycle is set to the desired pressure, start to turn gain up by say +5 each time until it starts to spike past your desired boost level, then either back the gain off slightly or back off the duty cycle slightly. It's completely trial and error. If you set say 12psi on a hot summer day, expect the pressure to get to 13-15psi on a freezing cold night.

I live near long deserted country roads with no speed limits so finding a flat straight road is no problem when I tune my Gizzmo MS-IBC. If I had a dyno I could probably tune a Gizzmo EBC in about 15 minutes, so maybe look at getting it dialed in at a workshop with a dyno. Much cheaper than loosing your license over.

its a tedious process.. if it were done on dyno in forth then you can just do simple adjustments on the road for the other gears, keep raising the duty till you get the boost right, then have someone watch the guage under full throttle and tell you if its holding or if its spiking/bleeding off

once you know exactly when full boost is eg.. 10psi at 3000rpm and holding steady to 7000rpm,

then simply up the duty up in the first 3000rpm, eg 90%duty upto 2500rpm and bleed the duty off to whatever worked for after 3000rpm.. that will give you the best ramping possible...

Be careful though, get it wrong and you'll blow that stock turbo up!!!!!!! :domokun:

thanks everyone....i ended up brought my 32 to the workshop and run on the dyno....they set it on 55% and stays on 12psi steady til 7000rpm....

but should i increase the boost or the duty cycle when im driving up the hill? coz sometimes im afarid to keep my foot on the throttle all the way up the hill....

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