as above really.

 

I bought some T28/T3 hybrids but before i get it mapped i need to find out what the maximum boost is i can run safely.

 

How would i go about finding this out??

 

These were custom made by the supplier as their stages didn't suit what i wanted so doubt they have any of those potatoe shapped graph thingys for them.

You can work it out theoretically with mathematics (and smokes and mirrors) but its pretty involved. My car has hybrid turbos and the previous owner spent a day or two with it on the rolling road to match everything up. He did well over 100 runs on the dyno trying different turbines until it got to the present state. I'm sure you could find the graphs that show T28/T3 hybrid most efficient boost ranges? Higher boost isn't necessarily better as they have a range where they work the best. I don't know enough about it to be of much help, but I'm sure the info is out there somewhere.

ok thanks i'll do some googling then

TBH mate i wouldn't be overly concerned about that just yet cos at the end of the day, the mapper maps the car using what boost he sees as giving the best results for both power and fueling together. As said, often the case of turning boost down gives better results. Certainly though the mapper would identify if the turbo's are running out of boost before the engine makes peak power and as your using T3's, these generally are built for high boost anyways, certainly from the cossie days ;) Finally from what I've seen of cars being mapped, somewhere between 1.2 and 1.8 bar seems to be the norm on higher powered Zeds which won't be a problem on yourt tubs..

cheers

smithy

As smithy says alot is down to the mapper, he can run and map more boost into your car until the turbos start to come out of their efficiency range and then they wont make anymore power

 

Just to give you an example when i had my car mapped with the 18g turbos i made more power at 1.4 bar than i did when it over boosted at 1.8 bar!! all your doing is then blowing hot air and risking the life span of your turbos so its not worth running silly boost for the sake of it!! you will possible find that around 1.5 bar is around the max that the 300zx engine likes possible 1.6 bar ;)

 

Mike

oh right cool, i'll leave it for the magical mapper then lol.

 

Thanks.

You'll know for sure when its too high as the turbos won't be able to achieve the set boost at higher revs - as the revs increase the boost will tail off ;)

You could get a charge temp sensor not too expensive!