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438 CATCAMS
- Thread starter The Dominator
- Start date
They all give very similar peak gains.
421s give more torque lower down but this can affect the idle, 438s try to mitigate this.
I'd just go with the cheapest based on what I've seen assuming you plan to stick with th stock manifold.
421s give more torque lower down but this can affect the idle, 438s try to mitigate this.
I'd just go with the cheapest based on what I've seen assuming you plan to stick with th stock manifold.
438's are 421's (almost exactly) but mildy modded to idle well using stock timing (and more importantly not stall at return to idle which is what 421's do on the stock inlet). 421's are awesome, always have been, but while they caused stalling it was a minor safety consideration. 438's are limited to who sells them, so obviously those who can only get 421s will say it's a waste of time. Essentially it's just making it easier to run the best cams for a stock internals F4R
GT racing cams have been around for ages (literally years), but they've had huge OEM projects so never really properly marketed their performance range. As i said, I started dealing with them over these cams 3 years ago
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I was, it's not exactly uncommon to keep contacts you make while employed though. and similarly I could do the same, or have something else done, which I might do eventually
Anyone who is expecting anything dramatically new from an F4R camshaft is likely to be dissapointed TBH
There are so many physical limits on what you can do with the profile, such as lack of clearance on the pistons limiting extra lift, limited valve acceleration rates caused by the hydraulic lifters, the standard ecu limiting the amount of overlap that can be handled etc which in turn has implications on LCAs and total duration.
Its only ever going to be a tweak to an existing profile when there are so many already about and all confined within relatively narrow parameters.
There are so many physical limits on what you can do with the profile, such as lack of clearance on the pistons limiting extra lift, limited valve acceleration rates caused by the hydraulic lifters, the standard ecu limiting the amount of overlap that can be handled etc which in turn has implications on LCAs and total duration.
Its only ever going to be a tweak to an existing profile when there are so many already about and all confined within relatively narrow parameters.
Heres a Friday morning question for you Chip.
How much power and torque do you reckon you could create from a bone stock F4R that had a completely dynamic valvetrain setup. A camshaft that can change its lift, duration and any other possible variable on the fly at any given RPM. (i guess like pneumatic/hydraulic systems on an F1 engine). Its something that always interested me.
How much power and torque do you reckon you could create from a bone stock F4R that had a completely dynamic valvetrain setup. A camshaft that can change its lift, duration and any other possible variable on the fly at any given RPM. (i guess like pneumatic/hydraulic systems on an F1 engine). Its something that always interested me.
Very acedemic question giving that it would cost millions to develop etc.
And the "bone stock" is even more acedemic as the head would have to be completely different, recast to allow the new components to be squeezed in etc so you would end up with different CR as well if you wanted by definition.
The limit is pretty much 100lbft per litre generally speaking for any N/A engine though when going into those sort of levels of development, and power is then a function of revs, so if you wanted to use standard rods and bolts you'd still be stuck at sub 8krpm really, and the standard pistons wouldnt allow you to even hit that 100lbft per litre target, so I reckon even 250bhp would be about it even with the worlds best inlet setup and exhaust and all the changes you mention.
I was involved in a project that gave me access to chat to some of the Toyota F1 people to talk to and they were saying that they could see over 20Krpm reliably from their engine but the rules didnt let them. At those sort of rpm, you can near to 350bhp per litre N/A, but obviously thats not on any of the standard F4R bits, but thats pretty much the limit of technology at the moment.
TBH if you want big power from a standard F4R bottom end the most sensible way of doing it is forced induction really, especially when the 197 head fits straight on and makes 260bhp/250lbft a piece of cake judging by the results we got from Jack at MWM's turbo car that I helped map.
R5 gtt, R27 F1 team
I really whorship you Chip! Wish i had contacts like that!
I'm a F16 mechanic which has pretty high tech stuff however it's fairly outdated.
The technology is great but as mentioned pretty much any 2012 car has the same put in it.
Don't forget the F16's technology is almost 40 years old...
I'm a F16 mechanic which has pretty high tech stuff however it's fairly outdated.
The technology is great but as mentioned pretty much any 2012 car has the same put in it.
Don't forget the F16's technology is almost 40 years old...
imprezaworks
ClioSport Club Member
Mk5 Golf GTI :)
I want chip on my team for my next pub quiz lol
Flol, you really wouldnt mate, im actually s**t at that sort of thing, science questions im ok on but things like entertainment and celebrities or sport or any modern music I really havent a fecking clue, and pub quizzes dont normally have a camshafts or turbos round, lol
imprezaworks
ClioSport Club Member
Mk5 Golf GTI :)
Id take that chance, cant be any worse than we normaly get on.
