Probably way over due an update to the progress...
As there was still no options for replacement cams for the later K4M engines, I bought a replacement cylinder head and sent it away on holiday to Belgium for CatCams to work on some profiles. I'd already seen the casting of the inlet ports and had already decided that the new head would have a thorough work over anyway as the finish isn't bad, but way short of good.
I decided that I didn't like the gloss black center surround. So sent the bits away and had them flocked by Thomas and Vines.
Cylinder head work by Automotive Machine Services
http://www.automotivemachineservices.co.uk/
Inlet ports machine bored, throats worked, valve seats recut to three angle seats instead of a single and new guides pressed in. Original valves retained as they are quite large for the original port sizes and big enough to flow over 180hp as going oversized would be Clio200 valves, which will probably be a waste of money.
The exhaust side had the throats worked, the roof of the port opened out where there used to be a thick boss, valve seats recut and new guides.
Chambers had work around the valves, to unshroud the valve. Polished out the casting marks and then refaced the gasket face to restore the compression ratio.
Fast road profile camshafts from Catcams
Billet ground and heat treated, with a bit more lift and more duration. Stage 2 cams
For anyone wanting to know the profile specs for the original cams and the new profiles
Specs are:
A/ STD specs:
- intake: 254°@0.1mm / 213°@1.0mm / 10.65mm (5.40mm)
- exhaust: 250°@0.1mm / 201°@1.0mm / 7.95mm (4.00mm)
B/ stage1 (5504701):
- intake: 261°@0.1mm / 223°@1.0mm / 11.25mm (5.69mm)
- ehxaust: 241°@0.1mm / 203°@1.0mm / 9.25mm (4.68mm)
- intended for factory or mapped ECU
- runs on std cam followers and valve springs
C/ stage2 (5504702):
- intake: 265°@0.1mm / 227°@1.0mm / 11.50mm (5.81mm)
- ehxaust: 249°@0.1mm / 211°@1.0mm / 10.25mm (5.18mm)
- intended for mapped ECU
- runs on std cam followers and valve springs
Regards
Matt
Catcams N.V.
UK Sales & Technical Representative
www.catcams.co.uk
Which makes the original RS133 cams look fairly wild when compared to the 5502702, 703, 704 series upgraded camshafts for the earlier k4m-700 series engines :shock:
KTR 4-1 manifold
Dini was booked in with K-tec to have the head replaced with the ported one and to fit the new profiles. KTR had ordered a set of cams as soon as mine were released and they got around to fitting them the day before I went down, with them dropping straight in and being roughly mapped in without any problems. As we found out after fitting my set of cams and it pulling 175hp peak but, not being happy to idle, I've got a stage 2 grind and KTR the stage 1's. The MAP pressure in the inlet plenum was all over the place compared to a standard car or the stage one profiles. So, Dini was abandoned down South whilst cam timing was adjusted and many mapping sessions were done to improve the low down drivability and also start looking at their Gen90 ECU for the Twingo.
With the bottom end of the rev range now running much better and having a few things to sort out before FCS, I went down and picked the car up. Splitting the 600 mile drive back home, neatly worked out with the North west Group having a RR sesh...
I know its only a guide, as it was a long time since I was down at RS tunning and the roller setup has moved in the mean time. Original graph from the remap which is back on page 2 of the thread
Saturdays graph from the Rolling Road shootout, where three of the clios recorded readings with in 1-2Hp of recent visits to RSt.
I've scaled the graph from Saturdays RR shootout to fit the scale on my original RSt graph.
As expected, the bottom end of the graph still sucks but I knew that would be the case before picking it up. If we can sort the 3000-3500 dip to some extent then I'll be more than happy.
I'm happy now anyway, but theres certainly more to come as AT Power now have the old cylinder head to design some direct to head throttles.
Now dropped onto BC Racing coilovers which have completely transformed the handling for the better compared to Cup suspension or Cup dampers and Apex springs. Now, much sharper turn in, soooo much grip and softer too... Go figure.
Anyway, your probably borred by now, but that's the main bones of the thing updated, omitting a few bits