I've had my 2 liter ZVH rst on the rollers last week, deliverd nice power but the revvs stopt @ 6000.
it's a little annoying because my turbo really starts spinning @ 4500 rpm
Goes like hell to 5500 and then slowly to 6000.

Thinking of putting on a smaller turbo to get full boost @ around 3500 but it should rev much higher!!!

what could be the problem... wrong cam timing??
Bought an adjustable poulie yesterday and wil fit that soon but when that's sorted should i get more revvs or could there be something else wrong...

Thanx a lot

 

that is a shite power band but you have got a 8v head which just abouts supplies enough air for a 1.6, trying to feed a 2.0.
what ever turbo you are running its not speced very well full boost @ 4500rpm

 

well.. i've seen zvh's making revves over 7000 rpm.. i've got a stage 3 head with a kent 35 cam... that should be enough for at least enough flow to reach the standard limiter shouldn't it?

I know the powerband is shit..... boost should be there at least at 3500-6500....

 

zvh making power @ 7000rpm look at what ever graph you where looking at again.My 2.0zvh shows peak power @ 5929 but i can still rev it to 7000 cant see the point if its not making power. who mapped your car because at one point my was showing 368bhp at 6592rpm on 26psi but when he up the boost and adjusted the timing and fuelling i lost revs.

 

hey, i didn't say it made power at that revv range, just said the engine could revv that high.. mine just stops @ 6000 rpm...peak power is @ 5550.

it has't properly been set up because it's getting to hot.
But just asked if the problem with my revvs could be in wrong timing..

Will sort that and then will get it set up propperly.

Don't think you know the guy who's setting up my car... local tuner here in Holland

But i'm not gonna get verry high revs then....so i'll have to change the turbo to get boost a lot earlier,,,
any idae what turbo to use??

Thnx

 

What turbo have you got? ZVH's do not rev very well sadly.

 

My little CVH is still making good power after 6500! It is on full boost (2-Bar)by around 4000rpm too.

As others have said, the ZVH' s do fail in the high rpm area.

 

my bad did'nt notice you came from holland for your application 4x4 cosworth hybrid turbo will come on boost nice and early and still make good power, or better still try a roller bearing turbo and cheap but do the job.

 

I've got a stage 3 turbo from universal turbo's.. cosworth turbine wheel, 0.48 exhaust housing and 360 degrees bearing.. had it on my 1.6 before this but as zvh wón't rev verry well i have to put on something else

 

do a search for posts by Andy_R he posted a ZVH power graph up not long ago

 

Hmzz... 4x4 hybrid turbo.. what specs am i looking at then?
What turbine and exhaust housing (what parts are standard 4x4 and what's hybrid? )??

and when will it kick in and what boost can i run it?

Thanx again

 

https://passionford.com/forum/viewto...892&highlight=

try that..

the car runs a t38 and about 25 psi

peak is at 6k

 

u'd need to goto a 63 housing. Being on boost at 4k is not good - my turbo is bigger than yours and mine's a 16...

 

custom speced gt30 roller bearin on my 1600 on boost at 2500rpm full boost(2bar) at 3800rpm still makin power over 7000rpm

same turbo on a zvh on boost at 1500-2000 rpm

they both run tubular manifolds aswell

 

63 housing... is that on a cos turbo or do i need to get a hybrid??

 

verry verry nice , but i think that;s a little over my budget.....

 

Over 7000peak power can be achieved but will require different inlet and exhaust manifolds and things then do start to get pricey......

Fitting a smaller turbo will give you better spool up but peak power will remain around the 6k figure.....just the nature of the ZVH unfortunatley.

 

I can live with peak power 5500-6000 rpm

Just wanna know what kind off turbo to fit then......

Goal is tot get full boost at aroud 3000-3500 rpm @ 20 psi

 

Cant see why your not getting boost earlier tbh, with the turbo your using you should see full boost way earlier than 4500rpm....something's not right!

Personaly id focus my attention on making what you do have work more efficiently, rather than spending money on another turbo.

 

Hmzzzz, buit what could be restricting the turbo from making boost earlier???

Got a rolling road graph of my rst and it shows boost is full @ 4500rpm....

What should be the rpm for full boost with my engine and tubrbo???[/img]

 

Should certainly be seeing full boost around 3000-3500rpm.

 

Hmzzz.. what could be the problem then ??

 

If it's the graph that you are relying on to decide when your turbo is making full-boost, then it really is important that the rolling-road operator used an accurate method for measuring RPM.

Stuart, what torque does yours make at 7000rpm?

 

on the 1 graph i got its makin around 240-250lbft @7000 that wasnt the finished map so dont no

 

It's not just on the graph but also when i'm driving it... it takes ages before i get some acceleration and @ arround 4500 it goesssssss....




http://www.mijnalbum.nl/Foto=DHTSDGY8

 

I would like to see a clearer image of that graph.....

 

Can't seem to upload it any bigger.. check your email..

 

I have seen the graph, thanks.

I would suggest that you check the adjustment of the actuator and that the wastegate is functioning correctlly (not jammed).

That would be my starting point.

What actuator is it?

 

Ok thanx, will do that.

Got an old actuator here so will try that on just to see if it's spinning op bettter.

My current actuator is supposeed to be an -65 or something.. swapped it for a -31 never should have done that.....

gonna buy a -31 again.

thnx for now..

 

Yes, fit a -31 and set it with the right amount of pre-load. If it's holding the wastegate open, it will certainly give the effect of additional lag.

Keep up posted with what happens.

Also, take a quick look over the hoses and Intercooler etc for leaks.

 

Put on an old actuator... does't boost higher then 0.5 bar.. have tot tighten it but no time for today.... turbo spins up earlier @ around 3500 it seems....
couldn't try it good though...... got out of fuel on the highway ... and got towed away bij my dad's corsa

 

But are you setting the pre-load correctly? How are you doing it?

 

I get the rod from the actuator of the wastegate en turn it in or out ... then pull out the rod and slide it over the pin on the wastegate..

 

i would put half a hole of pre-tension on the wastegate

 

That's about what i got now....

building pressure now from 2500 rpm and ful boost at arroud 3500

 

So would you say the problem is cured? (and my diagnosis was correct??!!)

 

Yes.. you could say that...

I had the amalvalve on with the -65 actuator with no pre-tension.

Now i've got a standard actuator and a bleedvalve in staed of the amal-valve...

Boulding up boost much earlier and full boost is earlier too.

now i've got the problem of boost getting late after i've changed gears.. takes halve a second before it's there but i'll open another topich on that couse we're wondering off the subject what this was originaly about..

Thanx a lot all