TU5JP4S, cams - what fits?

[welshpug]

Pretty simple question really, what will the standard JP4S C2 VTS valvetrain tolerate, and also how much space is there at TDC?

A friend has a C2 Code (LTD ed VTS) and wants to make it go faster

So please suggest a Newman, piper or Kent profile that'd be suitable for him.

Newman list:

PH1, 256 deg, 8.68 max lift, 0.87 @ TDC, 18-58 opening/closing and 110 deg peak.

PH3, 264 deg, 9.01 max lift, 1.55 @ TDC, 22-62 opening/closing and 110 deg peak.

£300 the pair which is a lot less than I'm used to seeing, coming form Knowing XU's.

Edit, Piper dont list any.

Kent only list a VERY mild one for the JP4, which would only take it up to standard JP4S power level, 240 degree, 8.53 peak lift, 0.53 @ tdc inlet, 0.35 exhaust. 10-50 degree opening, measured at 0.1mm.

[welshpug]

anyone?!

[Bobo0907]

Catcams make the 705's which are made for the JP4. Not sure on specs though? Worth finding out?

[KamRacing]

There are a few issues with the C2 VTS. Firstly the springs are weak, limiting cam profiles as you get valve bounce at high rpm. Also the throttle is fly by wire so has a fit when anything half decent is used.

The Cat Cams 1323703 (http://www.kamracing.co.uk/car-tuning/citroen/citroen-c2/engine/camshafts/citroen-c2-1-6-16v-vts-cat-cams-1323703-fast-road-trackday-camshaft.html) is about the limit you can run on a standard engine and ecu.
To compare this is INTAKE 248° , EXHAUST 240°, with 9.5mm inlet valve lift and 9.15mm exhaust

I'm not convinced Newman has ever tested their camshaft profile to get it running on a standard ecu.

Kev

[welshpug]

but they're different springs to the VTR JP4 engine, is it still the case they are weaker than the J4 106/saxo engine?

not wanting to use cat tbh.

[xsi16v]

but they're different springs to the VTR JP4 engine, is it still the case they are weaker than the J4 106/saxo engine?

not wanting to use cat tbh.

I'd guess so. Even though the lift is slightly more on the JP4s cams to the J4's, C2 VTS's dont rev as high. That'll be the reason for the weaker springs.

[KamRacing]

They are certainly not as strong as the saxo ones so the same issue applies as the VTR. To be honest the main issue is the ecu and fly by wire. This is limiting what the engine can do first...

[consvts]

i was thinking of a jp4 conversion after reading this would best thing to do be replace the springs with uprated ones?

[KamRacing]

depends on what cam you want to run. You can use saxo springs as a cheap upgrade.

[consvts]

would they hold a turbo on top tho?your kam racing springs would work wouldnlt they?

[KamRacing]

We are talking engine valvetrain right? The springs that control the valves..

[consvts]

ya i was thinking of rebuilding the hold head any way with racing valves aswell

[saxova]

I'd guess so. Even though the lift is slightly more on the JP4s cams to the J4's, C2 VTS's dont rev as high. That'll be the reason for the weaker springs.

Standard C2 VTS limiter is 7200, C2 VTR limiter 6500 :y:

I believe i have the VTS engine but haven't checked, Either way it gets rev'd to 7k often. Even hit the limiter by accident in the heat of action a few times (7600rpm) no tapping / problems :y:

[KamRacing]

The standard camshaft is relatively short duration compared to the newman camshaft profiles. This is where issues will occur. The standard engine can cope with its internals.

[blackie_2k5]

Standard C2 VTS limiter is 7200, C2 VTR limiter 6500 :y:

I believe i have the VTS engine but haven't checked, Either way it gets rev'd to 7k often. Even hit the limiter by accident in the heat of action a few times (7600rpm) no tapping / problems :y:

just a case of as and when not every time mate

my vtr ran fine for ages with the shitty silvertop springs..hit the limiter a few times when playing with other cars and had no issues

then one day got valve bounce and clattered piston number 3 with an inlet valve

:n:

[jeffchiz]

Catcams make the 705's which are made for the JP4. Not sure on specs though? Worth finding out?

they have the same lift and duration as the saxo 708 cam, i think im right in thinking they are the same except that the cams are offset to sit over the jp4 followers correctly however these do need the saxo j4 followers, retainers and valve springs as well as an aftermarket ecu

[KamRacing]

the Cat Cams 1322705 (http://www.kamracing.co.uk/car-tuning/citroen/citroen-c2/engine/camshafts/citroen-c2-cat-cams-1322705-trackday-camshaft-set.html) is not for use with standard C2 valve springs or standard throttlebody/ECU.

It does work well on the saxo where you can swap the springs and run a saxo inlet / ecu

[jeffchiz]

Isn't that what i just said? lol

[KamRacing]

i just wanted to reiterate to make the point well and truly clear :D

[welshpug]

so what if I don't want Cat?

[jeffchiz]

you have to use cat to be a saxp baws

[welshpug]

a what?

[jeffchiz]

http://www.urbandictionary.com/define.php?term=baws

[welshpug]

well I'm not African American, or Scottish.

[jeffchiz]

ah i see well im afraid you cant use cat then..

[welshpug]

that's fine with me, I don't want to :lol:

[jeffchiz]

lol just out of interest, why not?

[KamRacing]

Schrick don't make one, Kent cams don't make one, Estas will copy an existing camshaft but won't test or know whether it will work, Newmans don't make one that will fit a road engine, Cat Cams are not wanted.. You are running out of manufacturers!

Therefore turbo it instead :D

[welshpug]

He'll have to just get some made up through Sandy then :p

[KamRacing]

Sounds more expensive for no gain...

What are you trying to achieve that you cannot get from the Cat Cams?

[welshpug]

an engine that doesn't wear its top end out!

[xsi16v]

I have had no issues with my catcams in the 180 engine, and there is far more work in these cams than TU's with it having VVT.

I wont touch on the subject of catcam pulleys though :panic:

[blackie_2k5]

Catcam pulleys are gay.. I had one ages ago :(

My mapper said he'd never deal with catcams again after a 2 hour phone call to get some timing specs for a custom grind cam they had made for one of his customers, not only could they not provide, they couldn't tell him what was custom about it and how they'd came to reccomend/spec that can for his engine lol

[KamRacing]

an engine that doesn't wear its top end out!

can you explain? You've had premature camshaft wear or valve train wear?

[KamRacing]

Catcam pulleys are gay.. I had one ages ago :(

My mapper said he'd never deal with catcams again after a 2 hour phone call to get some timing specs for a custom grind cam they had made for one of his customers, not only could they not provide, they couldn't tell him what was custom about it and how they'd came to reccomend/spec that can for his engine lol

There certainly was an issue with some of the peugeot pulley's not being true. Sandy had lots of issues. Not sure if they changed the design/CNC programme to sort this.

With the issue of the custom camshaft..its going to depend on who designed it as to what information there is available. I could spec a camshaft and get them to make it and they would not take any interest in timing etc.
The worrying thing is the customer was completely clueless to what camshaft he had. I've got a custom VW camshaft sitting on my desk ready to be installed and its not going anywhere near a car until I have the detailed specs of the final design!

[bigezz]

this is a pretty pointless thread clearly cat is your best option

[welshpug]

why is asking what clearance an engine has pointless?

I spoke to an engine builder and he wouldn't use Cat unless the customer had bought them due to the issues with how they make their profiles and stuff wearing.

[axsaxoman]

never seen a saxo top end wear out with any make of cam --pinto,s vauxhalls ,fiats yes --not tu engines
must be some other reason
yes it is a bit of a pointless thread as if you fit anything much wilder than std the fly by wire will not like it at all on the c2 .
and as the ecu has full adaptive mapping its hard to do anything with it anyway .
any engine bulder or cam maker will not warranty piston clearance on aftermarket cams --thats up to you as the fitter to check and make mods as required.
early c2 engines had slight piston cut outs --then later ones do not --so its not something i would do without having the head off and using clay on pistons =dry build and turn over the ngien -remove head and see how thick the clay is --that will tell you how much clearance you have