8 replies to this topic

[Tom180489]

Hi guys ! I've had my Rs mk2 for around a month or so now , love the car ! ..... However when giving the car some beans so too speak my turbo boost pressure seems to drop , more so in a higher gear like 4th but even 3rd I think .... For example 2nd gear hits maximum pressure 1.8bar and holds until I change gear , this doesn't happen in 3rd and 4th it gets up to maximum 1.8 bar , but then starts to drop off slowly while I still have a good number or revs to go until "redline" as such . You can notice a drop in power so to speak I assume obv because the turbo pressure has dropped off. Like I said I'm new here and in the world of the Rs car before was a civic type r , so if you guys could give me any reason why this is happening or if that's supposed todo that , would be very much appreciated , thanks Tom.

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[Tom180489]

Sorry guys maximum boost is at 3/4 then drops off to 1/2 , not 1.8 bar rookie error , but yeah same problem applys

[James1989]

It won't hold the boost right up the revs, mine has had a jam sport map an Colin's map an the both boost to 3/4 the drop off to half higher up the revs.
It's no like a type R were you have to rev the of it to get the power not really much need to go over 5500rpm

[Tom180489]

Thanks for the reply , so basically as mine is completely standard your saying that it's supposed to drop out of boost after 5500 revs or round about that mark ? Because I read on some ford site that they were designed to hold maximum revs right through every gear to redline , not that I redline my car every gear just using as example ... ? Thanks for reply , ... No very different to the type r

[Robcat]

Yep, as James says, it can only hold peak boost for so long on the standard turbo.  Expect it to start backing off from around 5500-6000 revs - this is normal.  

 

As your revs pick up and the engine turns over more, the capacity of air going through it is much greater; you would need a fairly high flow turbo (which normally induces a bit of turbo lag) to maintain the boost at those flow rates.  

 

A lot, if not all, turbo cars work to the same principals.  It seems worse in 3rd and 4th gear etc. as you hold on to the throttle longer.  It would happen in 1st and 2nd, but it flies through the revs so quick to maximum that you probably don't have time to see the boost drop.  

[Tom180489]

Thanks very much guys ! I can stop worrying now ! Problem solved ! Appreciate the help ...

[James1989]

Yeah you'd need a big turbo to hold boost at high rpm before the RS I had a run of 3 tuned turbo cars an they all tailed off at 5/6 rpm with out changing the turbo/cams or inlet manifold..

[RSROG008]

Crickey how do you manage to watch the boost gauge, when I am pushing hard its all I can do to hold the car on the road, but then I am running 375. I also think that the lack of a physical throttle tends to give a less than crisp feel.

[OliB150]

I'm kinda the same, given it a blip a few times with passengers and they always ask. "So how fast did you get to then?!" My response is always. "I have no idea, I was watching the road!"