Peter Douglas Winn Posted June 3, 2015 Report Share Posted June 3, 2015 Can anybody give a rough guess of the power of an early CC engine with a CF Cam Stromberg carbs? I don't believe what the garage is trying to tell me. They are saying with a fancy exhaust, 135 hp. I would have thought that would have been with a CP Cam: Quote Link to post Share on other sites
dingle Posted June 3, 2015 Report Share Posted June 3, 2015 My guess is that it would be close to the advertised (for what that is worth) 104 hp, depending on the CR. I doubt that the fancy exhaust system would add much. Berry Quote Link to post Share on other sites
RobinTR6 Posted June 4, 2015 Report Share Posted June 4, 2015 If you look at the posts for extractor manifolds you'll see some note a small improvement not 50% tho. If the head has been gas flowed , ports enlarged yes you'll get more, still nowhere near 50% tho. Quote Link to post Share on other sites
Peter Douglas Winn Posted June 4, 2015 Author Report Share Posted June 4, 2015 I just think. if a CF cam is put in with no other changes what's the diifrence between a CC engine and a CF engine? Just the head. Can a head make say 20 to 25 hp difference without changing anything. We know an exhaust is 3 to 5% max. Quote Link to post Share on other sites
jerrytr5 Posted June 4, 2015 Report Share Posted June 4, 2015 Is that at the wheels or estimated flywheel ? Jerry Quote Link to post Share on other sites
Peter Cobbold Posted June 4, 2015 Report Share Posted June 4, 2015 Given a USA spec low compression engine in good condition then a blower can give ca. 35% increase in bhp, and without the engine having to rev more. https://supertrarged.wordpress.com/2014/12/16/eaton-m62-blower-calculations-for-tr6/ Quote Link to post Share on other sites
Peter Douglas Winn Posted June 5, 2015 Author Report Share Posted June 5, 2015 Jerry I don't really know but it is not important in this case. I am trying to get a feeling. Is what the garage said possible or bull....? Quote Link to post Share on other sites
Peter Cobbold Posted June 5, 2015 Report Share Posted June 5, 2015 (edited) Lots of changes needed. Cam, head shave to 9.5CR, possibly valves/seats enlarging. Lots to sort out on intake air flows. Exhaust will make b***all difference. If standard exhaust is OK for 150bhp PI then you wont find it hurting 105bhp. Edited June 5, 2015 by Peter Cobbold Quote Link to post Share on other sites
astontr6 Posted June 5, 2015 Report Share Posted June 5, 2015 Dear Peter, Â If you get hold of TR Register CD Technicalities and look at Tuning and Performance Modifications Page 13 for a 1973 TR6 CF2115E. This article will explain all and is fully backed up by Rolling Road Tests. Looking at the test data supplied which is very comprehensive, here is a summary: . 1st Mod He changed the carbs to SUs. Power at rear wheels---- 68BHP 2nd Mod Moss Extractor Manifold/Exhaust, Electric Fan, Electronic Ign.---85BHP 3rd Mod Fully Gas Flowed Head, compression raised to 9.5:1, Piper Cam 32/72/72/32, Distributor as TR5, Facet fuel pump + regulator--- 118BHP NB. He had now removed the Moss system TT1200 and FS5204A and gone over to a 6 into 1 with a 2 1/4" Bore single pipe system. This gives more torque from 1500 - 3000RPM. 4th Mod 3 weber DCOE 40s ---131 BHP Â Â Bruce. Quote Link to post Share on other sites
Peter Douglas Winn Posted June 6, 2015 Author Report Share Posted June 6, 2015 This info is great and very interesting. In my case a garage man said that putting a CF cam in a bog standard CC motor and a Fancy exhaust would give me 135HP. Is that true? I find it very hard to believe. Bruce, I would like to go down the road as you showed above but I am now getting a little bit long in the tooth. Anyway it suggests that my doubts are justified. I am starting with an early CC engine. Has anybody put a CF cam in a standard CC engine? Quote Link to post Share on other sites
astontr6 Posted June 6, 2015 Report Share Posted June 6, 2015 Dear Peter, Â I suspect that your cyl. head is the early type! In my view if you want to tune your car you need the later cyl. head post 1972 as per the PI models, fully gas flowed and it will have 9.5 compression. This in my view would mean that you are not going to have trouble finding a 6 branch exhaust manifold to suit your car, on a single pipe system. The cam shaft that I quote is hotter than the CP type and a proven performer, but I do not see much point in putting in a CF type! If you want a comparison on power a CP engine produces about 108 to 110 BHP at the rear wheels. in standard form, this figure was also confirmed by TR Enterprises when I attended the engine seminar!!! Â Lastly, torque is the most important thing that you are looking for and that conversion with SU or Weber produces a lot more torque in the 1500 to 3000 RPM range, which is where you want it, for road use. If you go down the tuning route buy all your parts from the same proven source. Â Bruce. Quote Link to post Share on other sites
Peter Douglas Winn Posted June 7, 2015 Author Report Share Posted June 7, 2015 Unfortunately, at the moment I am stuck with what I have got. An early CC head. The garage man has put in a supposedly PI Cam. I think it is only the CF Cam. He has give me written statement that it is 135 HP. I don't want to have the hassel of going to a Rolling Road. That's why I am trying to get some basic feed back from you lads. Or, as I say some dammed good, gut feelings.(They are always the best) Quote Link to post Share on other sites
astontr6 Posted June 7, 2015 Report Share Posted June 7, 2015 Dear Peter, Â I do not know the part numbers for a CC or CF cam but the part number for a genuine BL CP Cam is 307689. This number is either cast or engraved between 2 of the lobes and has 2 slim rings on one of the end bearing journals. Also I would have thought that the springs for the valves would have to be changed, if using a CP cam? Â You do not say what sort of exhaust system he proposes? Â Bruce. Quote Link to post Share on other sites
Peter Douglas Winn Posted June 8, 2015 Author Report Share Posted June 8, 2015 As far as I can tell he did not change the springs. I have reasons to believe the cam is Part number 311399!!!!!!!!!!!!! (hence my disbelief) The exhaust is a 6 to 2 to 1. Quote Link to post Share on other sites
TriumphV8 Posted June 8, 2015 Report Share Posted June 8, 2015 Tuning is not a cooking recipe, will say one can not say put this and that together and get XXX HP! Â Often I could see fitting the best things together and the result was awful! If basics in the engine are changed it is essential for getting it all work together to adapt carb needles an ignition. Â On the other hand the stock engines are mass production and individual setup and a simple optimizing of cylinder head, manifold gaskets and carb and ignition will give impressive results if not perfect before. Â Serious work on the engine starts with AFR measurement and ignition control on the basic engine not to fool yourself about the tuning work carried out later that mainly was a proper setup of the engine! Â So besides the knowledge that properly tuned carb TR6 are positioned in the range of 135-150 HP, except they are done by some people who cheat with the dyno sheet :-) the only reliable answer is a acceleration with a smartphone and look for 0-100 Km/h or better invest for a rolling road test. Â Maybe from what I could read here that will be disappointing...... Quote Link to post Share on other sites
Peter Douglas Winn Posted June 8, 2015 Author Report Share Posted June 8, 2015 That's a good idea. I have a tom tom that gives me accurate speeds. Also the markings on the motorways will help for distances. Can I do this on a very new engine? Something from the past says don't push a new engine. How many miles does one have to do before one can measure the acceleration? We are nearly back to the rolling road which I wanted to avoid. Quote Link to post Share on other sites
TriumphV8 Posted June 8, 2015 Report Share Posted June 8, 2015 400 Km should be minimum before full load is applied. Than accelearation is only for few seconds in first, second and third. That should do no harm..... Quote Link to post Share on other sites
Guest ntc Posted June 8, 2015 Report Share Posted June 8, 2015 Full chat from the off if it can't stand it start again drive a hire car and you will see Quote Link to post Share on other sites
astontr6 Posted June 9, 2015 Report Share Posted June 9, 2015 Dear Peter, Â The camshaft part number you quote is for a MK2 PI saloon or TR6 CR (125BHP DIN Scale) or 2500 TC 1974 saloon. Cam ring I/D is 3 slim rings, timing18/58, lift 0.240". The CP cam (TR6 150BHP?) is 2 slim rings timing 35/65, lift 0.250. Â But, I have to agree with what TriumphV8 says in his last sentence. 'Maybe from what I could read here that will be disappointing......' Â Bruce. Quote Link to post Share on other sites
Peter Douglas Winn Posted June 11, 2015 Author Report Share Posted June 11, 2015 Thanks Everybody. From what you have said has caused me to send the car to another garage with a rolling road. I will let you know what they say. Quote Link to post Share on other sites
Alec Pringle Posted June 11, 2015 Report Share Posted June 11, 2015 Hi Peter,  going back to your original post, the man is talking unadulterated bollocks - bullshit optimism, firmly based in fairytale land.  Cheers  Alec Quote Link to post Share on other sites
john.r.davies Posted June 12, 2015 Report Share Posted June 12, 2015 There are rolling roads and rolling roads, and then rolling roads that understand Lucas Pi. The last are the rarest of all. I'll need or soon as I'm running in a 2l on Pi in my Vitesse. I'll be grateful for reccomendations, almost anywhere in the country, as an RR owner who doesn't know Piwould be worse than nothing Thanks! Â John Quote Link to post Share on other sites
Andy1966 Posted June 12, 2015 Report Share Posted June 12, 2015 John   http://www.wilshers-garage.com/rolling-road  Peter Baldwin has always had positive feedback in my experience based at Wilshers Garage in Orwell Cambridgeshire, see attached link  He used to race classic mini's and there are some fantastic videos on youtube of him in action.  It is my Intention to take my car to him when ready   Andy Quote Link to post Share on other sites
Alec Pringle Posted June 12, 2015 Report Share Posted June 12, 2015 Hi John,  Dennis Vessey . . . . .  Cheers  Alec Quote Link to post Share on other sites
HarveyCoppock Posted June 12, 2015 Report Share Posted June 12, 2015 Dave Crofts Motor Services, Barrow Hill, Chesterfield (next to The Roundhouse) has a rolling road, and used to club rally a 2.5pi Saloon. Has done work to my 6. Quote Link to post Share on other sites
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