what's the highest safe rev limit for a saxo vtr?

[AzzAW93]

Hi my cars getting remapped soon as i want a higher rev limit. so i want to know whats the highest i can go whilst still being safe.
ive heard you can safely get them revving at 7500rpm on standard internals is this true?
its a late 2000 onward vtr engine with blacktop head springs.
thanks

[Quick]

Is it cam'd?

[AzzAW93]

it is yes with a cat cam 4901202

[Tom5190]

You may not need that limit though, no point in having a 7500rpm limit if power starts dropping off at 6800rpm really.

[AzzAW93]

indeed mate but ill be fitting a omex limiter anyway to bring it down to where the power ends, but just for initial setting up purposes whats the highest i can go so i can work back :)

[Tom5190]

Off the top of my head im not sure but the mapper will set your rev limit accordingly, he/she should run it up on the rollers to get an initial graph then work from there. Rather than setting a high limit and going backwards.

[AzzAW93]

ok but lets just say will 7500rpm be safe?

[Tom5190]

Like i said mate i dont know, but my 16v is set at 7700rpm, power starts dropping off around 7500rpm.

[Gandi699]

rallyes ran the harder green springs green springs and were limited to 7250, I'd say play it safe and set it to that

[martin1985]

just out of interest what is the rev limit on standard vtr?

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[Ross]

your mapper should be doing a power run on a safe (or standard) limit. If the power is still increasing at the point of limit, then he may elect to increase it. As posted above, if the power declines after (for example) 7000rpm, why have the limit higher?

[blackie_2k5]

Defo wouldn't be going anywhere near 7.5k on a roller rocker head

[Ross]

Defo wouldn't be going anywhere near 7.5k on a roller rocker head
Ah totally forgot 8v... Good spot!

[axsaxoman]

std springs on a roller type engine tend to float above 6600rpm with a non std cam
so fit "green springs and caps" to match and then you can rev to 7500 no problem
the spec of cam will decide what rpm its worth revving too anyway and a cam that idles fine in a std ecu set-up will give max power well below that rpm proably 6500 tops --so no point in revving that high anyway
If were wanting to rev to 7500 i would not be using roller rockers
cams are ground differently to suit type of rocker gear used as the rocker ratio is different for roller + early solid type of rockers

[AzzAW93]

So what were thinking is, I'm safe to go to 7500 but if the power drops off before then that's were ill set the limiter?

[sam_16v]

mate just set the limit to 6800-7000, 7.5k will be a waste of time

[Dave_P]

Set it 500 rpm above peak power.

[Ross]

Set it 500 rpm above peak power.

This. Likely to be around 7k max on an 8v of your spec (the limit, not maximum power).

[AzzAW93]

Its pug1off doing the mapping and they don't have a rolling road as from what I've heard and read only wayne at chipwizards has mapped the 3plug vtr ecus but I can't get hold of him, and he's miles away.
That's why I want to know the highest safe limit I can go so I can then wire in a omex rev limiter and launch controll at a suitable rpm if that makes sense :)

Cheers for the help

[sam_16v]

tom5190 who has commented in this thread works for pug1off irrc

[m4tt274]

My VTR engine started to loose power after about 5800rpm and it was the head at fault, it couldnt breath well after that. Yours may be slightly different but wouldnt imagine 8K would be necessary, probably 7K

[Ross]

My VTR engine started to loose power after about 5800rpm and it was the head at fault, it couldnt breath well after that. Yours may be slightly different but wouldnt imagine 8K would be necessary, probably 7K

where'd you get this "8k" figure?? I'd not put my engine to 8k rpm!

[AXracing]

indeed mate but ill be fitting a omex limiter anyway to bring it down to where the power ends, but just for initial setting up purposes whats the highest i can go so i can work back :)

Are you talking Omex ECU or stand alone rev limiter? As the stand alone rev limiter on its own will not let you rev any higher then standard.

[Gandi699]

exactly what he said above, the omex is only going to let you set it below the standard rev limiter unless you have the standard one moved

[blackie_2k5]

Not just the top end you have to worry about

[AzzAW93]

Are you talking Omex ECU or stand alone rev limiter? As the stand alone rev limiter on its own will not let you rev any higher then standard.

exactly what he said above, the omex is only going to let you set it below the standard rev limiter unless you have the standard one moved

This whole thread is about me lifting my standard limit to however high is safe and then bringing it down to the best rpm for performance via a standalone rev limiter if the mappers don't do that as standard.
So say if 7500rpm is safe ill up the standard limit to that. And if peak power is at 6800rpm I will then set the omex rev limiter to 7250rpm :)

[chrisrallye5]

Well Pug1off will know what they are doing as he has done many of them, and as someone said tom works for them and his revs to 7.7rpm.

[Dave_P]

A stand alone rev limiter won't increase your rev limit if your using the std ecu.

If Wayne (chip wizards) was mapping the std ecu I presume he could increase the rev limit at the same time.

[Ross]

Well Pug1off will know what they are doing as he has done many of them, and as someone said tom works for them and his revs to 7.7rpm.

Tom also has a 16v does he not? We're talking about the 8v lump, which cannot rev to the same limits.

[axsaxoman]

My VTR engine started to loose power after about 5800rpm and it was the head at fault, it couldnt breath well after that. Yours may be slightly different but wouldnt imagine 8K would be necessary, probably 7K

that is very typical of using std "white"valve springs on a roller rocker car with high lift cam --the springs "float"
its not a breathing problem of the head .IE porting + valve size

[AzzAW93]

A stand alone rev limiter won't increase your rev limit if your using the std ecu.

If Wayne (chip wizards) was mapping the std ecu I presume he could increase the rev limit at the same time.
Does nobody read?
I'm getting my standard limit raised and then will set a apropriate revlimit via a omex limiter if pug1off don't do it already

[Dave_P]

At no point have you mentioned what ecu/valve spring & caps your using... :err:

If your mapper car raise the rev limit why faf about with the omex?

[AzzAW93]

At no point have you mentioned what ecu/valve spring & caps your using... :err:

If your mapper car raise the rev limit why faf about with the omex?

I mensioned in the title I had a late vtr with blacktop springs (admitedly I forgot to mension caps but they are to from a black top vtr)

I then mensioned in a reply I have a 3 plug vtr standard ecu

And the omex rev limiter is because they don't have a rolling road so I didn't know if they can work out where to set the limiter.

Obviously I don't know much about how this works so I apologise for not giving the proper info

[Ross]

wait a minute. You're car's getting remapped. On the standard ECU. It's a 3 plug ECU.

The mapper doesn't have a rolling road.

Where's it getting mapped? (Who by?)

[blackie_2k5]

Unless its getting live mapped while driven and using proper afr gear

Stay well clear

Edit-- unless its actually getting dyno mapped, which is ideally the best, don't just let some money put a generic map on it without doing anything

Just thought I'd make that clear :p

[Ross]

Who live maps (or engine dynos) a standard 3 plug ecu? I don't know of anyone?

:detective:

[blackie_2k5]

Chip wizards do

Automarc in stokesly does. ( he's good mates with Wayne apparently)

Don't know of anyone else mind

[Ross]

They map on the road?? Thought they both had rollers?

Either way, road mapping is a fucking bad idea ...

[blackie_2k5]

No they have RR mate :y:

Was just pointin out that unless its at least road mapping the stay well clear, as in stay away from generic mappers who do mobile maps etc

Ideally RR is best

[Ross]

Gotcha!

I was expecting my negative comments ref road mapping to get more interest tbh ;)

[Dave_P]

May i suggest you, sell/don't buy the Omex rev limiter thing & spend your money buying a Predator ECU instead of remapping your std ECU with a company that doesn't have a RR...

[sam_16v]

May i suggest you, sell/don't buy the Omex rev limiter thing & spend your money buying a Predator ECU instead of remapping your std ECU with a company that doesn't have a RR...

this :y: pred's are well worth the money

[axsaxoman]

the omex unit will not be able to override the std rev limter unless you were intending to make the rev limit lower than the std ecu --which is not the case i suspect--so its a waste of money -
If you mapper can adjust std ecu rev limter ,then no need for an omex unit anyway.
i WAS NOT AWARE THAT WAYNE COULD TOTALLY REMAP THE 3 PLUG ECU AS ITS A TOTALLY DIF ECU THAN THE SINGLE PLUG UNIT.

I would check properly that he can do the 3 plug unit --this is in no way having a dig at wayne --he knows his stuff .
All i will say is every 3 plug equipped car i have seen that has been remapped (by whom i do not know) gradually reveted back to std map as they had not got ridf the auto correction function of the ecu .

same goes for c2 ecu,s ,which are basically same unit but using fly by wire throttle

[blackie_2k5]

Gotcha!

I was expecting my negative comments ref road mapping to get more interest tbh ;)

i know lots of ppl have neg comments about road mapping..if its done in safe areas i see no major harm to it (other then risk to your license)

i get road mapped as your probs aware..hence the post? ;)

the serious runs are done on a very long/quiet stretch of dual carriageway..the rest is done round town etc at safe speeds

seems to have achieved very good results on my previous engine..and keeps cost to me down :)

if i had a trailer to go further afield...or someone local i trusted with rollers...id go to them

but not many ppl like that up here..and even fewer who will touch predator


there are many horror stories of road mapping..but as said..if not driving like a totall tool in silly places you shouldnt have too much risk

[blackie_2k5]

the omex unit will not be able to override the std rev limter unless you were intending to make the rev limit lower than the std ecu --which is not the case i suspect--so its a waste of money -
If you mapper can adjust std ecu rev limter ,then no need for an omex unit anyway.
i WAS NOT AWARE THAT WAYNE COULD TOTALLY REMAP THE 3 PLUG ECU AS ITS A TOTALLY DIF ECU THAN THE SINGLE PLUG UNIT.

I would check properly that he can do the 3 plug unit --this is in no way having a dig at wayne --he knows his stuff .
All i will say is every 3 plug equipped car i have seen that has been remapped (by whom i do not know) gradually reveted back to std map as they had not got ridf the auto correction function of the ecu .

same goes for c2 ecu,s ,which are basically same unit but using fly by wire throttle


dont quote me on it as i dont know the ins and outs (or even if its true) but read somewhere he writes the new map in the limp mode or a diff area of the ecu and runs it on that??

supposedly can now map the OE ecu for bodies and turbo as well...

[AzzAW93]

i heard he takes out a chip in the ecu and replaces it with his own mappable version but again its only what ive heard.
this also seams to be the way pug1off want to do mine. ill email them now and ill confirm or deny this roumer :P

[ChAdS]

I will remap it for you it's a Lego block chip that will map your standard ecu while it's parked up not running stick it on top of your ecu and I will watch you drive off


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[Ross]

Re road mapping.

I challenge anyone to hold a 100% load site at 7500rpm on the road.

[blackie_2k5]

It was really awkward first time I done it I'll agree to that haha

Had 2 or 3 sessions now, you get used to it :)

[Ross]

It was really awkward first time I done it I'll agree to that haha

Had 2 or 3 sessions now, you get used to it :)

7500rpm 100% load in 5th gear is 160mph on my car. I don't have the ability (skill) to hold a set load site at these speeds. Holding a 90% load in 5th gear? 10% maybe I can do with some consistency. No WAY could I do anything close to full throttle. I struggle to keep the car in a straight line at close to full throttle, let alone trying to hold an exact % throttle position!

A dyno on the other hand brakes the rollers to hold any load site, at any throttle position, at any RPM. I'll stick to that thanks ;)

[blackie_2k5]

My rev limit is 6250 and it ain't as fast as yours hahA ;)

Once you get used to keeping fixed rpm it's not too bad.. I drive for a living in a speed tracked van, so I'm already used to fixed throttle position driving

Long straight with smooth Tarmac ain't to bad

[Ross]

My rev limit is 6250 and it ain't as fast as yours hahA ;)

Once you get used to keeping fixed rpm it's not too bad.. I drive for a living in a speed tracked van, so I'm already used to fixed throttle position driving

Long straight with smooth Tarmac ain't to bad

http://t1.gstatic.com/images?q=tbn:ANd9GcSp3w7srxkq7yaJb-6qtMZXINfCHhxw-wjI5iBs-nNn0R_v1OzwUA

[blackie_2k5]

Nahhhhh :homme:

I may it have Saxo much longer if something changes tonight..

[Ross]

Nahhhhh :homme:

I may it have Saxo much longer if something changes tonight..

you ditching this french tin can and buying a proper car? :D

[blackie_2k5]

I wouldn't call it proper.... Technically not a car either lmao

But we'll see what happens tonight

[AzzAW93]

all done.
was mapped today at chipwizards and the limit is now set at 6900rpm :)
cheers all

[blackie_2k5]

what power...

[AzzAW93]

129.7bhp

[blackie_2k5]

what was the spec

[AzzAW93]

what was the spec

1.6 8v with;
catcam 4901202 track spec cam
421 manifold
streight through ashley race exhaust
ecosse ram air induction kit
black top head springs