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performance cams



RSTuning

ClioSport Club Member
  R35 GTR
438s. No compromise. Perfect idle, best gains

Best gains based on what?

421's are the same profile with different timing so providing you get the 421's to idle they WILL make more power than the 438's. At a guess the exhaut will be retarded a few degrees to make the idle but this will take power away compared to not having the r****d.
 
  Golf GTD Mk7
522be181-be3f-382d.jpg


Power delivery is excellent on the 421's timed to Renault spec. 204bhp and 170lbft with a high comp setup :)
 
  DON'T SEND ME PM'S!!
Best gains based on what?

421's are the same profile with different timing so providing you get the 421's to idle they WILL make more power than the 438's. At a guess the exhaut will be retarded a few degrees to make the idle but this will take power away compared to not having the r****d.

they're close, but thats not actually the only difference. The timing changes have no measured negative effect
 

RSTuning

ClioSport Club Member
  R35 GTR
Surely the only difference is lift at tdc as that's not shown on the profile?

No doubt they are a food cam profile but till I'm proved wrong I'll stick with the 421's :)

We'll find out in jan as we are doing some testing
 
  182/RS2/ Turbo/Mk1
With the rod ratio on these engines being so poor, the high RPM performance is really compromised by the standard compression ratio, but im still surprised to see you got so comfortably over 200bhp from that setup, fair play :)

Got a full spec list anywhere or a build thread?

Long shot but dont suppose it has been on a DD dyno anywhere, im just more used to figures from them so would be easier for me to compare to other engines?
 
  Golf GTD Mk7
No build thread sorry, but it's essentially a race car bottom end. Acl main bearing, arp bolts, high comp pistons with 421 catcams, v6 airbox and cnc'd inlets up top. RR is TDF so is recognized to be accurate. She pulls very nicely low down and gets a bit giddy above 5k :)
 
  182/RS2/ Turbo/Mk1
No build thread sorry, but it's essentially a race car bottom end. Acl main bearing, arp bolts, high comp pistons with 421 catcams, v6 airbox and cnc'd inlets up top. RR is TDF so is recognized to be accurate. She pulls very nicely low down and gets a bit giddy above 5k :)

Wasnt trying to say the rollers were high or low or anything, just that i'd have liked to have seen a DD one as its what im used to, no offence intended.

Can certainly see the step up in performance at 5K :)


What ECU is that on? Standard with a remap I take it if you are still running the standard inlet etc?
 
  LY R26 230 F1 Team
No build thread sorry, but it's essentially a race car bottom end. Acl main bearing, arp bolts, high comp pistons with 421 catcams, v6 airbox and cnc'd inlets up top. RR is TDF so is recognized to be accurate. She pulls very nicely low down and gets a bit giddy above 5k :)

how much was that work at TDF? if you dont mind me asking, PM me if you prefer?
 

Chris205

ClioSport Club Member
  Many Things
He's already said its high comp mate, so he's obviously changed the pistons.

Sorry mate I knew that I was more interested in what other parts had been used i.e different valves, head work, other work done to the bottom end bar pistons :)

No build thread sorry, but it's essentially a race car bottom end. Acl main bearing, arp bolts, high comp pistons with 421 catcams, v6 airbox and cnc'd inlets up top. RR is TDF so is recognized to be accurate. She pulls very nicely low down and gets a bit giddy above 5k :)

That's the answer I was after :)
 
  Golf GTD Mk7
But no profiles disclosed? Surely they would put something up considering it's their name on the cams? Regardless of exclusivity.
 
  HBT 172 Cup
Think im going to treat myself to a set of these cams for my birthday this month, 186bhp starting point should make for some interesting results..
 
  182/RS2/ Turbo/Mk1
Would be interesting to find out why yours seems to make more power than other engines to begin with, must be something different about it but I guess you dont know enough of its history to know if its been played with or not?
 
  182/RS2/ Turbo/Mk1
Maybe its down to cams and piston combo? Never seem many on here running a forged set up just with cams

Hotter cams on every engine Ive ever tuned work well with higher compression.
At the top end of the rev range where the induction stroke timebase is so diminished it means that what little intake charge you manage to get into the engine you really do want to be able to work as hard as possible, so with cams working better higher in the rev range, its a natural marriage between them and higher comp.
 
  e92 + E46 M3 + Cup
438:
5502438 276 / 268 240 / 231 11.25 / 10.25 mm

421:
5502421 276 / 268 240 / 231 11.25 / 10.25 mm


Certainly looks like Rs Tuning is correct that the only difference is the timing centreline based on the specs quoted.



Wow 428's could be back up in value if there is a cam setting tool that could allow them to be set the same as the 438's!

Any one that knows my history with Catcams know's why I would never touch a set again, I was one of the lucky one's who ended up with the duff batch of 428's, What a pleasure that was fitting then driving to holland for Henk to calibrate to tell me they had been machined wrong, Yay! then JMS bought a set of 421's for the race car that were machined wrong on the VVT end, Yay again!

Hopefully 438 means they have finally pulled there finger out!
 
  172
Would be interesting to find out why yours seems to make more power than other engines to begin with, must be something different about it but I guess you dont know enough of its history to know if its been played with or not?
theres a few about Chip mines not as high as Laines but mine made 182bhp in november and thats standard
 
  HBT 172 Cup
Its the silver cups, renault put special engines in them ;)

I'm binning the air con on mine too, should free up an extra horse or two aswell.
 
  Ph1
Wow 428's could be back up in value if there is a cam setting tool that could allow them to be set the same as the 438's!

Any one that knows my history with Catcams know's why I would never touch a set again, I was one of the lucky one's who ended up with the duff batch of 428's, What a pleasure that was fitting then driving to holland for Henk to calibrate to tell me they had been machined wrong, Yay! then JMS bought a set of 421's for the race car that were machined wrong on the VVT end, Yay again!

Hopefully 438 means they have finally pulled there finger out!


Same as me :(

Did Cat Cams replace yours? - They did mine but lost out ££££ on lost fitting and mapping costs.
 
  e92 + E46 M3 + Cup
Same as me :(

Did Cat Cams replace yours? - They did mine but lost out ££££ on lost fitting and mapping costs.

Yes they resolved the 428's same as you, Lost out on all the fitting/ removal, cambelt kit, aux belt, driving across Europe etc... all part of the fun :(

421's on the other hand were ball ache to get resolved, Still not completely happy.........

I was told there were only a couple of stray 428's on the market but seems there are a few still out there from the word I've heard over the past months, Hopefully a thing of the past for the 438!
 
  Ph1
Yeah was told the same, only a couple of dodgy sets.

Would never have known they were dodgy if it wasn't for having different cams fitted previous and had a comparison to go by.
 


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