asland Posted June 21, 2013 Report Share Posted June 21, 2013 Hi I have with limited success scrolled this Forum for recommendations for camshaft for a CP TR6 PI 150 bhp. The engine will be completely reconditioned with a Peter Burgess cylinder head and extract exhaust system. I have not decided yet whether to recond. the PI or to use a 3x Weber 40 DCOE set-up I have hanging on my wall. I constantly read about the fantastic 150bhp PI camshaft but with 100 000 miles on the clock, the camshaft have seen better days. My question is therefore: WHICH CAMSHAFT WOULD SUIT MY NEEDS? I see Kent has a TH6 cam with close to similar spec as the 150 bhp PI. Piper has its TR6BP285. MOSS has TT10405N & 12041N and Newman also has similar spec cams. One thing I am certain about - I do not want a regrind, but a new cam! Has anybody experience with these camshafts or recommendations? Thanks! cheers Halvor Quote Link to post Share on other sites
Nick Jones Posted June 21, 2013 Report Share Posted June 21, 2013 I understand that Newman Cams make a copy of the original CP cam. Choice of cam will depend on how you plan to use the car. A friend of mine has an ex-US TR6 with UK head, EFI and a Newman PH1 cam (their mildest, described as not for PI for some reason) and that goes like the clappers. Was downright scary on the original 3.7 diff and only slightly tamed with a 3.45. Dead flat idle at 600rpm and pulls from that point. Nick Quote Link to post Share on other sites
whatmore179 Posted June 22, 2013 Report Share Posted June 22, 2013 Halvor, There’s loads of info here on cams. Just recently about cams wearing within a very short time period......very short. I had my engine rebuilt at the beginning of last year and decided on a Newman Cam. I’m very pleased with the results. Steve Quote Link to post Share on other sites
asland Posted June 22, 2013 Author Report Share Posted June 22, 2013 Quote Link to post Share on other sites
Damson6 Posted June 23, 2013 Report Share Posted June 23, 2013 (edited) I think you need to consider how you are going to use the car first and chose a profile to suit? Also properly set up PI will be more economical than Webber's In my experience, Webber owners will see it differently! I had a new Kent cam it lasted about 15,000 miles max. Now running standard 150 cam best for normal road use? Edited July 3, 2013 by Damson6 Quote Link to post Share on other sites
Red 6 Posted June 25, 2013 Report Share Posted June 25, 2013 If want to run the webbers then 285 deg which think is the th5 cam is as wild as you can go can go for a road car, (it is to do with the fact webbers need vacuum to suck the fuel air mix in and PI does not) and over 285 deg the vac disappears (yes I know it is not as simple as that) For PI 295 is about it, unless you like revving to 2k every time you pull away, but you will need the metering unit tweaked. To help decide go to kent cams website where you will find info on where power comes in and where it goes out, for example a power range between 3k and 7k is no good for towing a caravan just as 1100 to 2500 wont win any traffic light GP's. So my recommendation is 285 to 295 degrees, and forget any nonsense about high lift, that just munches lobes. If you want high lift go to roller rockers etc. As to who to buy from, I always bought from Kent and the results were fine, my 306 deg cam lasted 16k road and race miles. Quote Link to post Share on other sites
asland Posted June 27, 2013 Author Report Share Posted June 27, 2013 Thanks for all assistance!! I'll stay with 285 deg...Then comes the difficult question: Newman, Piper, Kent , ...... cheers halvor Quote Link to post Share on other sites
Tom Fremont Posted June 27, 2013 Report Share Posted June 27, 2013 My first experience with Webers was with a Kent TH2 cam having 295 degrees of duration. Compression ratio of 9.5:1 and no other changes from stock TR250 and the behaviour was vice-free and a tremendous upgrade from original performance-wise. Vacuum didn't disappear though it decreased enough to require larger idle jets than the 240 duration original cam ( according to the books - I never tried it ). I went through (2) Kent grinds in 35K miles with followers showing the worst of it. Same engine has a P.I. repro with " Motorsport " followers with an additional 70K miles now done and still behaves as when new. A reworked head with new / different springs was fitted with the P.I. cam as well. More important than a few degrees of duration or 10ths of inch of lift are (1) compatibility of followers with cam and (2) proper springing for the valves / cam profile. Note that there are two ways these cams and followers are ground: (a) tapered lobes with crowned followers and ( true flat lobes and followers. Followers can be checked by placing them bottom to bottom; if they rock they're crowned. Lobes may be checked with a micrometer from side to side. Whichever you believe to be correct or best for TRs it's clear types shouldn't be cross-mixed . I had pitting after 150 miles on a flat cam with crowned followers ( different example from above ). Quote Link to post Share on other sites
TRTOM2498PI Posted June 27, 2013 Report Share Posted June 27, 2013 I run a TR6 with Lucas PI. I use a Newman cam, which is a hybrid cam, and understand it is similar in spec to that of a Piper Yellow cam. Mine came direct fron Newman with steel followers. X 4 tracks later, a 10 Countries run, and general hard driving over the last two years, and do far so good. Cam is lovely and quiet and has power from idle and will rev to the end of red line. Will advise results of RR once I have re-visited. Cheers. Quote Link to post Share on other sites
Ragtag Posted June 28, 2013 Report Share Posted June 28, 2013 As to who to buy from, I always bought from Kent and the results were fine, my 306 deg cam lasted 16k road and race miles. Sorry, are you suggesting that 16k miles is a good return? Quote Link to post Share on other sites
roulli Posted June 30, 2013 Report Share Posted June 30, 2013 I run a TR6 with Lucas PI. I use a Newman cam, which is a hybrid cam, and understand it is similar in spec to that of a Piper Yellow cam. Mine came direct fron Newman with steel followers. X 4 tracks later, a 10 Countries run, and general hard driving over the last two years, and do far so good. Cam is lovely and quiet and has power from idle and will rev to the end of red line. Will advise results of RR once I have re-visited. Cheers. Can you be a bit more precise about the " hybrid cam from Newman"? I know their camshaft types PH1 (260°), PH2 (280°) etc. I run a PH1 cam on Webers for + 10000km without any problems. Cheers, Patrick Quote Link to post Share on other sites
Red 6 Posted June 30, 2013 Report Share Posted June 30, 2013 Sorry, are you suggesting that 16k miles is a good return? Absolutely and unequivocally without any shadow of a doubt yes. The engine was built to rev to 8k (8.5k if you ignored the big red light) which is what it did when asked, which was quite often. My friend bought the car from me and successfully raced it in the sprint and hill climb championship for several years. I think if I still owned it it would have done about 3k miles in 7 years and would have lasted forever (possibly). What a car, what an engine. Mmmmmmmmmmmmmmmmmmm happy days. Quote Link to post Share on other sites
whatmore179 Posted July 1, 2013 Report Share Posted July 1, 2013 (edited) Ive the Newman PH3 Cam, http://www.newman-cams.com/catalogue.html In the catalgue it states power band from 3000 to 6500 RPM. Id say that this is wrong and a misprint, in that mine pulls like a train from 1500 through to 6500. ( only ever to 6500 on the RR, usuallly take her up to 5000). I also purchased the 12 x Induction Hardend EN40 B Nitrided EN40 B Steel Cam Followers Cam Followers at the same time. Steve Edited July 1, 2013 by whatmore179 Quote Link to post Share on other sites
asland Posted July 2, 2013 Author Report Share Posted July 2, 2013 Hi Steve I am rebuilding my engine to fast road / stage 2+ spec with a Peter Burgess head, etc. but I am slightly hesitant on the PH3 cam for fast road use....?? 300 deg seems somewhat wild even though you say it pulls strong from 1500... Could you give some more info on the state of tune on your engine? cheers Hal Quote Link to post Share on other sites
whatmore179 Posted July 2, 2013 Report Share Posted July 2, 2013 Hi Asland, I've sent you a pm Steve Quote Link to post Share on other sites
Red 6 Posted July 2, 2013 Report Share Posted July 2, 2013 300 degrees is ok for a PI, but I would have thought it would be a bit of a faff to drive in traffic. I appreciate you say it pulls from 1500 rpm, but for normal driving I would have thought that to accelerate when say overtaking from cruise you would have to keep dropping down gears to get some power when what is needed is torque and a lower power band, hence my recommendation of 285 for webbers and 295 (max) for PI as a road car. Mind you there is more to this than just degrees of advance, one has to consider the head, valve size, inlet tract and exhaust and so on. The cam is just a mechanical device driven by the crank for opening and closing the valves. Quote Link to post Share on other sites
whatmore179 Posted July 2, 2013 Report Share Posted July 2, 2013 Im no expert Red 6 i just asked my engine builder to build a great road engine with, as you say plenty of torque. With the head work also done by him Ive got what I wanted. No problem in traffic. steve Quote Link to post Share on other sites
jean Posted July 3, 2013 Report Share Posted July 3, 2013 Halvor, before opting for a new camshaft seek advise from a specialist. When the engine on my 6 was overhauled at about 75k miles I was advised to retain the camshaft as it was still in perfect condition. It now got over 100k miles without any issue. As said the Original camshafts are of top quality and last forever, in my view much better than all that new garbage on the market. If you want to go racing, it's another piece of cake, but don't expect long life items Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.