Waldi Posted May 19, 2018 Report Share Posted May 19, 2018 Do we think after all this that we have helped the OP? Hi Pete, you are right. Hi Crops, sorry, typical engineers behaviour : you ask where you can buy petrol and we start explaining how a refinery processes crude oil. To answer your question, here is what I will do for my TR6: I just ordered a Revotec "puller" fan kit from Revington, but without the controller that is normally fitted in the upper hose. I will simply use a temperature switch in a new SS bottom pipe. If you order such pipe, be carefull, there are 2 styles of pipe, I have ordered the wrong one (for my car) from another supplier. It was cheap, but does not fit, one bend is to pronounced (hope that is the right word). The switch wil control the fan via a fused relay (to relieve the switch, as starting currents may be up to 20A I read somewhere, nominal is 9-10A). Fan, brackets, pipe, switch and relay all come from Revington. If you remove the Original fan (that is what I will do) you need a pulley adapter, which is part of the kit. I did not want the controller, I think a switch and relay are more reliable (there are a couple members on this forum that had a failed controller). If you are handy, you can find cheaper items I'm sure, but I wanted to buy something prooven. Good luck, Waldi Quote Link to post Share on other sites
Waldi Posted May 19, 2018 Report Share Posted May 19, 2018 (edited) Hi Pete, This may help to better understand some on this forum : https://www.youtube.com/watch?v=Dx6HojLBsnw Cheers, Waldi Edited May 19, 2018 by Waldi Quote Link to post Share on other sites
Rem18 Posted May 19, 2018 Report Share Posted May 19, 2018 Its just personal taste but I still say unless you need those 0.5-12hp just make your cooler system good and stay where Triumph made it, always worked fine for me on 2 cars. Before you start adding complications get what you have right. I use my 5 in Alpine events so it has an oil cooler which is not something likely to go wrong and was an option at the time, but I do know a lot of people with fans, many of them far wiser than me. Its just me I dont have Mx5 seats or power steering either. :rolleyes: T Quote Link to post Share on other sites
JochemsTR Posted May 20, 2018 Report Share Posted May 20, 2018 (edited) 5000 rpm will be around 12,5 HP.... sorry, these calculations are not correct. I agree with the 0,1 HP at continuous idle, and drag increases exponentionally over speed, which results in max 1-2 HP.... Sorry, I will not provide any calculations to prove my case. Anyone can make up their mind based on these messages. Just be realistic. If the mechanical fan would be such a contribution (10%), this would be the easiest and cheapest tuning upgrade there is. My dyno tests did not show any improvement going from mechanical to electrical. Why electric? Easy, the engine warms up faster and only cools when needed. That is it. The engine is not getting any better cooling! With a flushed and maintained system the mechanical fan works fine. The electrical fan is just as dependent on a good system as its mechanical version. Why sell horsepower?? Simple, why else would you buy such upgrades, in my opinion, just marketing. None of the Triumph shops have provided dyno data....they are very well capable of it, the reason, there is no improvement....with no improvement these upgrades are hard to sell and they may be held liable for misleading marketing. Jochem ".....if it is on the internet...it must be true..." Edited May 20, 2018 by JochemsTR Quote Link to post Share on other sites
Waldi Posted May 20, 2018 Report Share Posted May 20, 2018 Hi Jochem, The calculations are correct (3rd power increase with engine speed), the assumptions are not exact, that is why they are assumptions. I am surprised by the considerable power loss at higher RPM too, and doubted the outcome like you do. Best regards, Waldi 5000 rpm will be around 12,5 HP.... sorry, these calculations are not correct. I agree with the 0,1 HP at continuous idle, and drag increases exponentionally over speed, which results in max 1-2 HP.... Sorry, I will not provide any calculations to prove my case. Anyone can make up their mind based on these messages. Just be realistic. If the mechanical fan would be such a contribution (10%), this would be the easiest and cheapest tuning upgrade there is. My dyno tests did not show any improvement going from mechanical to electrical. Why electric? Easy, the engine warms up faster and only cools when needed. That is it. The engine is not getting any better cooling! With a flushed and maintained system the mechanical fan works fine. The electrical fan is just as dependent on a good system as its mechanical version. Why sell horsepower?? Simple, why else would you buy such upgrades, in my opinion, just marketing. None of the Triumph shops have provided dyno data....they are very well capable of it, the reason, there is no improvement....with no improvement these upgrades are hard to sell and they may be held liable for misleading marketing. Jochem ".....if it is on the internet...it must be true..." Quote Link to post Share on other sites
Rem18 Posted May 20, 2018 Report Share Posted May 20, 2018 Although I like Waldi's style (he appears to be a guy who learns by doing ) I am more inclined to agree with Jochem on this one, I think 99% is marketing as 12.5hp seems too much, and as I keep saying, its ugly having modern things in the engine bay and just another thing to go wrong. So it warms up a little faster, most people only use their TR's on nice days and a little warming before start off is good practice as warm water in the engine is not a full mechanical warm anyway. Someone needs to do that Dyno test but if you dont and want to give me the figures my son is studying as a mathematical physics PHD and I can ask him if he wants to waste time on a bunch of old TR men who are worrying about such things Quote Link to post Share on other sites
Colin White Posted May 20, 2018 Report Share Posted May 20, 2018 The way I see it is the notional hp saving would only be an issue at full throttle which I very rarely use. The main reason Iwent for an electric fan was that I found the 13 blade fan on my CR was very noisy particularly at higher revs, so this enabled me to remove it. Quote Link to post Share on other sites
Andy Moltu Posted May 20, 2018 Report Share Posted May 20, 2018 If your car overheats in traffic with the mechanical fan then the solution is unlikely to be an electric fan. The engine driven fan is more than ample in much more tropical climates and you should look into why you overheated. Either you are producing too much heat (blown head gasket etc) or you rad is in need of a flush or re-core. Quote Link to post Share on other sites
Rem18 Posted May 21, 2018 Report Share Posted May 21, 2018 Yep Andy is right its what we are saying, need to check it all first before you decide.... My car only goes up to half after a burn even if I leave it running parked in hot weather and runs at about a 1/4 on normal running. Quote Link to post Share on other sites
BlueTR3A-5EKT Posted May 21, 2018 Report Share Posted May 21, 2018 (edited) As an aside.... Did any one ever try to fit the viscous coupling and fan from a late model Triumph 2500S to a TR5/6. Same engine,and the earlier versions used the same cooling fans as TR. The viscous coupling used is as far as I can recall the same as Stag, TR7 and Spit 1500. I do not think it is a thermostatically controlled fan clutch unit, that cuts in when the the air flowing through the radiator is hot. Peter W Edited May 21, 2018 by BlueTR3A-5EKT Quote Link to post Share on other sites
DaveR Posted May 21, 2018 Report Share Posted May 21, 2018 (edited) There are a number of red herrings concerning the electric fan. The main point of using one is it's only in use when required. Whereas the mechanical type is providing cooling when it is not required. The mechanical plastic fan is more efficient than the earlier metal type. The Viscous coupling mechanical fans go some way to doing the same job as the electric fan. However, there has always been some concerns about their reliability. Dave Edited May 21, 2018 by DaveR Quote Link to post Share on other sites
stuart Posted May 21, 2018 Report Share Posted May 21, 2018 There are a number of red herrings concerning the electric fan. The main point of using one is it's only in use when required. Whereas the mechanical type is providing cooling when it is not required. The mechanical plastic fan is more efficient than the earlier metal type. The Viscous coupling mechanical fans go some way to doing the same job as the electric fan. However, there has always been some concerns about their reliability. Dave Had viscous coupling fans on a number of XJ6`s and they were good when new but tended to seize eventually so just acted as direct driven ones in the end. Stuart. Quote Link to post Share on other sites
DaveR Posted May 21, 2018 Report Share Posted May 21, 2018 Stuart, Yes seizing up was the normal problem which could then result is very loud screeching noises! Dave Quote Link to post Share on other sites
Rem18 Posted May 21, 2018 Report Share Posted May 21, 2018 I was just reading how 1950 Lancia's had an extra thermostat that opened a blind in front of the radiator Quote Link to post Share on other sites
Hamish Posted May 21, 2018 Report Share Posted May 21, 2018 I was just reading how 1950 Lancia's had an extra thermostat that opened a blind in front of the radiator ROGER WHERE ARE YOU ??? he will be along in a bit to explain his Louvre project on his 4 Have a search it was a great experiment that many of us followed with interest. H Quote Link to post Share on other sites
Rem18 Posted May 21, 2018 Report Share Posted May 21, 2018 Hahahahah Hamish I've already got him on another thread regards how much he drives his car. See if you can spot the thread..... ROGER WHERE ARE YOU ???he will be along in a bit to explain his Louvre project on his 4Have a search it was a great experiment that many of us followed with interest.H Quote Link to post Share on other sites
RogerH Posted May 21, 2018 Report Share Posted May 21, 2018 ROGER WHERE ARE YOU ??? he will be along in a bit to explain his Louvre project on his 4 Have a search it was a great experiment that many of us followed with interest. H Hi Hamish, come the autumn the Venetian blind will be fitted again. I think I know a simple mod to improve it. Roger Quote Link to post Share on other sites
Rem18 Posted May 21, 2018 Report Share Posted May 21, 2018 Ahhh but this is a manual thing. The Lancia one was thermo controlled... Hi Hamish, come the autumn the Venetian blind will be fitted again. I think I know a simple mod to improve it. Roger Quote Link to post Share on other sites
RogerH Posted May 21, 2018 Report Share Posted May 21, 2018 aren't they all.! Roger Quote Link to post Share on other sites
Hamish Posted May 21, 2018 Report Share Posted May 21, 2018 aren't they all.! Roger I sense cunning stunt ........ or is it a an engineering solution that has had a great deal of thought and planning ?!?!????????? Quote Link to post Share on other sites
Rem18 Posted May 22, 2018 Report Share Posted May 22, 2018 Roger but one thing. Why close the louvre's as if it gets that cold the thermostat will close??? Quote Link to post Share on other sites
Waldi Posted June 14, 2018 Report Share Posted June 14, 2018 We lack (emperical) data, but we can still make an estimate... Electric fan: The electric fan which draws around 10A, has an electric power consumption of 10 A x 13V = 130 W, but the generator has an efficiency too, so the mechanical power consumption from the engine crankshaft (including the generator and fan belt losses) will be say 150W (approx. 0,2 HP). It is only needed at lower speeds (in traffic jam etc), and will run say 50% of the time only then (off course depending on engine condition, ambient air temperature), so the net required power is 0,2 * 50% / 0,1 HP for contiumuous cooling at idle. The efficiency of an electric fan will be better than the standard fan, since it has a shroud to minimize re-circulation, and it runs at a much lower speed, which improves volumetric efficiency. Mechanical fan: The standard mechanical fan (driven from the crackshaft) has a (very) poor efficiency to start with : It does not have a shroud, which increases recirculation It is some distance from the radiator so there is even more recirculation, which costs extra power (or reduces efficiency). Fan (volumetric) efficiency also reduces with fan speed. Power consumption increases to the 3rd power with speed (engine RPM), this is a law of physics. Comparison : Now if we know the mechanical fan is capable of cooling the engine at continuous idle speed (say 1000 rpm for this analysis), we can safely assume it will also absorb around 0,1 HP at 1000 RPM (a bit more due to its poor efficiency and a bit less since no energy conversion via the V belt and dynamo is required which also costs power) , but we lack data for a better guestimate. As fan power increases to the 3rd power with fan speed (rpm), the power absorbed by the mechanical fan at.... 3000 rpm will be around 2,75 HP (0,1 * (3000 / 1000)3 ) 4000 rpm will be around 6,4 HP (0,1 * (4000 / 1000)3 ) 5000 rpm will be around 12,5 HP (yes, do the math) Regards, Waldi Addition to the above: In the adapter kit I bought from Revington to replace my mechanical fan and adapter, there is a clear fitting instruction which mentions a saving of up to 6 hp. Regards, Waldi Quote Link to post Share on other sites
Z320 Posted June 18, 2018 Report Share Posted June 18, 2018 Hi Waldi, I own olny a small lathe with only 750 Watt power, but approx 1HP, god enought for me. If I fit my (BMW 1602) mechanical van on it, it should be only possible to run it until with 2.145 revs? Cioa Marco Quote Link to post Share on other sites
TriumphV8 Posted June 18, 2018 Report Share Posted June 18, 2018 As an aside.... Did any one ever try to fit the viscous coupling and fan from a late model Triumph 2500S to a TR5/6. Same engine,and the earlier versions used the same cooling fans as TR. The viscous coupling used is as far as I can recall the same as Stag, TR7 and Spit 1500. I do not think it is a thermostatically controlled fan clutch unit, that cuts in when the the air flowing through the radiator is hot. Peter W Here it is again: The viscous couplings are all very similar on Spitfire, Rover and Triumph. The fans also fit on several couplings. This is STAG fan and Rover coupling but Triumph/Triumpg looks similar Quote Link to post Share on other sites
TriumphV8 Posted June 18, 2018 Report Share Posted June 18, 2018 Hi Waldi, I own olny a small lathe with only 750 Watt power, but approx 1HP, god enought for me. If I fit my (BMW 1602) mechanical van on it, it should be only possible to run it until with 2.145 revs? Cioa Marco The BMW was quoted in the old bibles like Gert Hack BMW Alpina and "Autos schneller machen" with about 5HP but that bases on "normal" revs. But I do not think that is essential. The point is that a mechanical fan grabs power most when we do not need it at all. That is why nearly all car manufacturers do not use it anymore. That must have a reason. Mechanical fan is the cheapest and most reliable solution. Viscous coupling is still a weak point. Quote Link to post Share on other sites
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