boost problem

[N1SMO]

I have a turbo Dynamics md172 turbo (Norris t28 super hybrid) and i feel that the boost comes to late in the rev range i dont get full boost (1.5bar) till 5000rpm i feel this is very late for this turbo.
Can anyone who knows this turbo give me any ideas on when i should be getting boost or what the problem could be.

i have checked for the normal stuff like air leaks, dump valve wastegate creep.

could it be the cam timing that is out.

 

[zia]

how is the wastegate being controlled? is the ignition timing and fuel map all o.k?

zia

 

[GTIR-LOZ]

it could be fooked!!!!!!!!! how old is it?? might be worth checking for play in the shaft etc

 

[N1SMO]

the wastegate is being controlled by the boost solenoid valve through my gems ecu, have had it remapped but has made no difference. the turbo is only a year old and has been the same since new. just cat figure it out.
the cams were fitted by a garage who i will not name as they have not got a clue. if the set they timing wrong could it be the cause.

 

[zia]

surely if you,ve had a remap the guys who did the map would have noticed that the max boost was coming in higher?

zia

 

[Fast Guy]

if the set the timing wrong it it be the cause.

Did you mean "if they set the timing wrong could it be the cause?"
If the cam timing is out then I'd say yes. If they don't have a clue, I'd get the cam timing and valve clearances checked just to be on the safe side.

 

[N1SMO]

yes thats what i ment i was in a hurry when i typed up the reply.

can anyone with this turbo tell me what rpm they get 1.5 bar at.

how do i check the cam timing (have hks pulleys)

plus i dont think the shimmed after fitting the cams,

 

[Edd]

what cams did you go for?

they might be causing the boost to come in so late, if your handy, try fitting back the std cams and see if that brings the spoolup lower down the rev range

 

[zia]

1..remove the rocker cover
2.. turn engine until the mark on the crank pulley lines up with the pointer at tdc.might have take pulley etc off to see crank gear to get in tdc position
3.. check marks on camshaft .they should line up coloured link on the timing chain.
4..looking at camshaft gears the gears should have pointer with lines on each side.depending how its been set, it will either have the pointer facing anticlock wise for retared.and clockwise for advance. was the cam rattling if it isn,t it probably been shimmed o.k

zia

 

[N1SMO]

Thanks Zia i will check this out, Not sure what cams it was that i put in all i remember is that they were HKS

Your help is much appreciated guys

 

[skiddusmarkus]

1..remove the rocker cover

Make sure you have some liquid gasket before you do though as you need to use some next to where the cams run(you'll see where from old stuff).

What revs do you get say 1,1.1,1.2,1.3 and 1.4bar?If it's all or nothing at 5000rpm then I'd say something isn't right.If you're getting 1bar at 3500rpm and it builds up from there then maybe that's just the characteristcs of the turbo.
I think Ginga has that turbo-ask him at what rpm he gets different boost levels.
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