Having a discussion on another forumn about bleed valves and chipping. A guy is claiming that his RST had a one off chip by Ahmed Bayjoo that cut the boost pressure back once the ACT's were to high from 16psi to 7psi (iirc). And that the use of bleed valves is all wrong and the car should be setup to control boost from the ECU or have a stand alone EBC. He also claimed teh boost level should be chosen and then the car mapped accordingly.

Now I've already pointed out that the Bosch KE-Jetronic system is mechanical and therefor there is nothing to map. But the rest of the comments I would like some back up as to my thoughts before I make a tit out of myself.

1. I wasn't aware the ERST ECU could do such a thing with regards to the boost. I know when the ACT gets too high it knocks back the ignition timing so wouldn't a boost control feature even a crude one require an additional output from the ECU?

2. I'm personally of the opinion that there is nothing wrong with the use of a bleed valve, only the moron that fiddles once it's been setup.

3. Chipping an RST only removes the boost limit doesn't it rather than anything else more clever

??

 

he sounds full of shit, nothing wrong with a bleed valve, crude but works, i'd like to him tension the actuator after its just done a few runs in the dyno

 

Apparently the car used to belong to a guy who works for Burton and he himself used to. This doesn't render me full of confidence after their technical man told me no RST could do more than about 200bhp and all the cars claiming bigger figures were full of shit and the dyno graphs were doctored

 

Bleed valves are FINE.

NB: ONLY F SET UP BY YOUR TUNER!!!

Karlos did explain somewhere once why he uses them on his low power rst conversions, cant remember what he said tho.

 

The guy is correct really, they are not the correct solution in an ideal world but people want a low cost easy to do method of changing boost, so they are used.

The controlling of the boost I'm not sure about because I dont know how the ERST ECU works, but it should be possible as it has an amal valve doesn't it? Provided that you can modify the point at which the amal valve kicks in then yeah its totally possible.

JAmes.

 

Wouldnt it be safer just to have a hi/low boost switch ?,that way after its been set up there is no twiddleing the bleed valve and risking detonation.I have never used a bleed valve because it would be unsafe in my hands.Car setup,used to it "twiddle twiddle" more boost BANG !!

 

Hence my post, your tuner uses it if necessary, and you pretend its not there!!

 

Exactly.

Problem is there are a large number of gibbons out there that will insist on having a tinker, blowing their car up and then blaming the bleed valve when it was in fact their stupidity that caused the problem.

 

HA HA,I think thats always going to be the case,the only reason I dont mess with my sapp is I know the cost of parts if it goes wrong.Everything else I have owned I have always tried to make it faster one way or another.People cant help themselves but mess.

 

A friend once pulled the hose off the ecu on a s1

HOW FOOKIN FAST

^^ not recommended

 

oranoco th eguy is right you best go back and apologise lol
the ecu has a mappable ignition rev limit, full speed pressure ignition map tables,ect ignition table act ignition table,etc etc it also has a boost map which is rpm/ pressure /ect/act mappable. As well as many other functions

 

So if the ECU is so functional why don't we have more than a boggo shitty chip available?

 

what a doughnut

 

there are proper mapped chips available and has been for years since the 80's
we still sell them and have them in stock and can programme them whilst you wait

 

Well there you go. I am learned

 

Well i'm going to disagree with you, home built ones can be fine.

We've done a few with MSD kits and never had any problems. As long as you get proper checks done by a pro afterwards.

 

www.turbosystems.co.uk
prices are on my web site Ive been dying to be able to post that for years

 

Need to update your VAT though mate.

Sure it'll be of use to people. I'm not planning on taking mine much further now

 

So you have just answered both of the posts,mine and yours.I said once set up dont mess,2 way switch =safe if properly set up.You said about having it checked once you have installed the proper stuff which I also agree with.Fact is people dont.They mess because they know better or nothing and then dont have their diy checked because they think its dead fast so it will be ok.