BPU- 1 bar or 1.2

Im collecting all the bits together to go BPU, but i cant decide whether to just go with the 1.2 bar RR and be done with it, or put a 1 bar RR in and use a boost controller to turn it up to 1.2 when i want. I have a Profec B sitting here that i had on my Starlet, so spose i might as well put it on there really?

just go with the 1.2 RR

Mine runs at 1-1.1 and there is little in it to be honest.....your really squeezing every last bit of efficient power out of the turbos at 1.2+

Im collecting all the bits together to go BPU, but i cant decide whether to just go with the 1.2 bar RR and be done with it, or put a 1 bar RR in and use a boost controller to turn it up to 1.2 when i want. I have a Profec B sitting here that i had on my Starlet, so spose i might as well put it on there really?

Fitting a slightly small RR and using the boost controller will give you control over the boost, this would be the option I'd go with, especially if you already have the boost controller.

Thats what i thought. The fact is it will never go on low boost, but the intention was there lol

I would go with the 1 bar RR as well, that way in the winter when its nice and cold and you start naturally making a bit more boost you don't need to worry about it going over 1.2 bar (as you would with the 1.2 bar RR).

Jacko what are you using for fuel? i was intending to just get a walbro but from reading different things on the net i'm now considering a UK spec fuel pump instead, if only for the piece of mind i'd get from an OEM part.

where might you get a 1b rr? is this the usual for boost control, fit a smaller ring then up the boost as and when with the controller? can you get a 0.8b rr or will this create too much restriction?

Im going to use a Walbro pump and i know CW does a 1 bar RR, but i dont know if anybody makes a 0.8 RR, or like you say, if they would cause too much restriction

i know CW does a 1 bar RR

He told me he only did a 1.2bar one?

i pm'd him a while ago and im sure he said he did 1 bar RR's. If somebody gave me the sizes i could make them at work on the cnc machine

Each car is different and when BPU the peak boost pressure varies a great deal with outside air temp and humidity.

For example, the RR Chris usually supplies will be made to keep most cars at/slightly below 1.2 bar in cold weather conditions. In the heat of the summer, this might mean only 1.0 bar maximum.

I drilled my one out so that it ran 1.1 peak in the summer, but as soon as air temps dropped, or I drove it very early in the morning it went direct to 1.3 bar and fuel cut. So, if you had a RR that allowed 1.2 bar in yesterdays heat, this might reach 1.3-1.4 at night, or higher even in winter (obviously fuel cut would cut in before then, but thats not the point )

If you want year round boost adjustment you need to get a boost controller.

Ye, cheers for the help. I think i'll get an RR that keeps it as near to 1 bar as possible and turn it up with the Profec B when i feel the need (always) Then i can stop it boosting too high when the air temps come down

Ye, cheers for the help. I think i'll get an RR that keeps it as near to 1 bar as possible and turn it up with the Profec B when i feel the need (always) Then i can stop it boosting too high when the air temps come down

Yep, thats the best solution mate