Wastegate/Solanoid Hose Sizings & Boost in Low Gears.

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I am having a little bit of a problem with my SBC-iD.

In first and Second gear I can't hit 15psi of boost.

In first the max it hits is around 14psi then dropps off to around 13psi then in second it may hit 14.7psi then it will drop off to 13.6psi.

Third is a little longer so it seems that it has more time to get its sh it together and will hold boost to around 14.8psi.

Fourth sits perfectly on 15psi.

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In the manual it stresses to use the rubber hose supplied which is a smaller diam by about 2x over the origional wastegate/turbo rubber hose. It states to use a size changer.

How critical is this as I havn't done this and i'm using the regular fuel line size hose from the wastegate/turbo to the Solanoid.

I'm going to have a fiddle today but I would like to hear of any experience or your thoughts on this power loosing problem in low gears.

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All Sorted PPls.

Replaced the std fuel line hose size wastegate hose with the one supplied and walla.. It holds more stable boost without it going up and down 1/2 - 1psi and now along with the scramble setting set it rocks..

I've set it up to run 1.1 bar for 3secs then it levels out to 15psi.

First gear now pulls hard and so does second

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It doesn't actually increase performance it only holds boost better and safer.

Before with the std bleed valve setting the mid to around 15psi up over 5500rpm it would drop to 12psi.

It also helps with the tuning I guess as in hoter weather boost wont go as high with the trad. bleed valves and in cold weather the boost will be higher.

The best i could get with near std timing on 12psi was 152rwkw.

Agressive timing was 156rwkw.

Now with near std timing i'm getting 164rwkw.

Boost is a bit smoother coming on so its easier to control wheel spin, where as with the bleed it would spike to around 17psi cause wheel spin then settle on 15 then drop to 12.

You probably arn't loosing boost up top because of the bigger turbo not running out of puff like mine but another thing to keep in mind is that with the bigger laggier turbos a ebc can help bring boost on quicker.