R300 with Caterham power upgrade
Discussion
Long time lurker and now ready to join the fun. Looking at an sv 300k which has had the power upgrade from Caterham taking it to 200bhp.
I`m told it can be a bit jerky on light throttle ( I have not driven it yet ) and wondered if thats normal ? It has the roller throttles which again I`m told are tricky to set up ???
So , I bow to the PH greater knowledge.... should it be that different to a normal r400k ???? I will be getting a compression test before purchase to check all is well but have a ton of questions before we get there .....
Cheers
I`m told it can be a bit jerky on light throttle ( I have not driven it yet ) and wondered if thats normal ? It has the roller throttles which again I`m told are tricky to set up ???
So , I bow to the PH greater knowledge.... should it be that different to a normal r400k ???? I will be getting a compression test before purchase to check all is well but have a ton of questions before we get there .....
Cheers
culminator said:
Roller barrel throttle bodies do seem to induce jerking on a light throttle as I found out test driving a Duratec the other day. Ruined the experience.
I know lots of Duratecs (with and without roller barrel) do this but they don't have to. Properly set up and using a good quality fuel (shell/BP) will stop it. IMHO it is fuel vaporisation in the fuel line or fuel rail, rather than any particular issue with the barrels.Areyousure182 said:
Ok... so it shouldnt be a problem and can be sorted. Does an engine with 20k on it need any internal investigation or are they bullit proof at 200 bhp levels ???
if it's built well with good parts (forged pistons etc) it should be fine .. mine (touching lots of wood) has done 20,000 miles now with many trackdays and is fine.stef1808 said:
Thats the one ... ? Wadda ya know ??Roller Barels suffer from a couple of design issues whihc causes the idle to go off after around 1000 miles:
1) There is quite a lot of leakage around the actual rollers, so at idle it is hard to balance the two pairs.
2) There is no way to balance the two barels within a single TB. I am looking to desigh an air bleed modification to overcome this.
1&2 together exacerbate the need to regularly rebalance the bodies at idle, and ensure the TPS calibration is set properly. Easy but essential maintenance.
1) There is quite a lot of leakage around the actual rollers, so at idle it is hard to balance the two pairs.
2) There is no way to balance the two barels within a single TB. I am looking to desigh an air bleed modification to overcome this.
1&2 together exacerbate the need to regularly rebalance the bodies at idle, and ensure the TPS calibration is set properly. Easy but essential maintenance.
TeflonTurd said:
Roller Barels suffer from a couple of design issues whihc causes the idle to go off after around 1000 miles:
1) There is quite a lot of leakage around the actual rollers, so at idle it is hard to balance the two pairs.
2) There is no way to balance the two barels within a single TB. I am looking to desigh an air bleed modification to overcome this.
1&2 together exacerbate the need to regularly rebalance the bodies at idle, and ensure the TPS calibration is set properly. Easy but essential maintenance.
Seems about right according to my research so far. A "foible" if you will ! 1) There is quite a lot of leakage around the actual rollers, so at idle it is hard to balance the two pairs.
2) There is no way to balance the two barels within a single TB. I am looking to desigh an air bleed modification to overcome this.
1&2 together exacerbate the need to regularly rebalance the bodies at idle, and ensure the TPS calibration is set properly. Easy but essential maintenance.
TeflonTurd said:
2) There is no way to balance the two barels within a single TB. I am looking to desigh an air bleed modification to overcome this.
Not sure that is true - each port has a bleed screw that can be adjusted to match flow via a 'bypass' circuit in the casting. In part, that is why the front of the barrel is slightly open i.e. the bleed gets shut off as the barrel rotates. [edit to clarify: the bleed air route is through the front of the barrel (6mm gap), to a hole in the roof of the casting and the via the bleed screw to the engine side (photo) as it rotates past idle, it shuts off the hole in the roof] 
Edited by DCL on Friday 7th March 17:23
Edited by DCL on Friday 7th March 17:24
TeflonTurd said:
Why did you ask on here if you already knew?? You just wasted 5 minutes of my life!
I didnt already know , thats why I asked. I have been trying to get as much info when I get a spare minute to peruse the web. Your summary seems to fit with what I`ve subsequently read , so chill your arse down. The car in question has been reclaimed by its owner as it was a SOR which I didnt know so its a mute point now anyway. I hope the owner has fun with this summer but I will have one by the time he wants to give it back to the showroom for storage / sale.
stef1808 said:
Well , interestingly the owner of this car rings up Caterham all of a sudden and arranges to collect it post haste that day on the pretense that it will be used over the summer and returned for SOR at the end of the summer. Strange how it then, on the same day appears at GC Motors , back up for sale but this time in Yorkshire with an extra 205 miles on and a grand cheaper. Its also had an optional extra of a "Limited Slip Diffuser" bolted on .... WTF !Areyousure182 said:
Well , interestingly the owner of this car rings up Caterham all of a sudden and arranges to collect it post haste that day on the pretense that it will be used over the summer and returned for SOR at the end of the summer. Strange how it then, on the same day appears at GC Motors , back up for sale but this time in Yorkshire with an extra 205 miles on and a grand cheaper. Its also had an optional extra of a "Limited Slip Diffuser" bolted on .... WTF !
205 miles of sideways action ? 
[assuming you meant differential]its not my car, but i was actually interested in buying it a few weeks a go but have decided to pass for now
i like the idea of buying a already tuned car for a considerable discount - just need to bear in mind it was prob driven very hard by the previous owner
Edited by stef1808 on Sunday 9th March 17:46
stef1808 said:
205 miles of sideways action ? [assuming you meant differential]
its not my car, but i was actually interested in buying it a few weeks a go but have decided to pass for now
i like the idea of buying a already tuned car for a considerable discount - just need to bear in mind it was prob driven very hard by the previous owner
205 miles straight up the M1 more like !! I was actually very keen on it but now the owner has removed it to the other end of the country and told some lies along the way I`m not interested now. From all the advice I was given the engine would need pulling apart anyhow for a refresh and the claimed 200bhp was dubious..... but I had factored that into the budget. A previously tuned engine is worth a punt if it has good provenance. [assuming you meant differential]its not my car, but i was actually interested in buying it a few weeks a go but have decided to pass for now
i like the idea of buying a already tuned car for a considerable discount - just need to bear in mind it was prob driven very hard by the previous owner
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