marvmul Posted September 30, 2006 Report Share Posted September 30, 2006 I've bought a fully race prepared cast iron cylinderhead (newly casted), and purchased by chance an alloy head too, prepared in the same way as the iron head. The porting and valve diameter of the alloy head are a little closer to the limit, but I guess that the flowing and performance of the two heads will be about the same. I started building a new engine for my TR3 race car, and one of the two cylinderheads will be used. I prefer the alloy cylinderhead, but doubt about it because a lot of people have warnings or bad experiences with the alloy castings : headgaskets blowing in the first place but also collapsing of the casting around some of the studs. Most people pretend that the alloy heads are only usable for rally or fast road cars. All comments, warnings, experiences and advise is much appreciated. Quote Link to post Share on other sites
JRCWeedon Posted October 6, 2006 Report Share Posted October 6, 2006 Hi I had a Moss aluminium head on my old TR4 and had a lot of head gasket trouble. I used a solid copper gasket which is arguably harder than the aluminium so may have contributed to the problem. The initial problems were overcome by using a higher torque setting (70lb/ft by Moss increased to 85 after advice). The sprints and hillclimbs were OK but as soon as I got near a trackday ( similar to a race in length ) problems started. I had some lengthy discussions with Jon Wood of Classic Racecraft who reckoned that it was caused by the different coefficients of expansion between a cast iron block and an aluminium head and the head studs having no "give" in them. I believe he had some very expensive waisted studs made up but he is notoriously difficult to contact. Jon said that any engine with an aluminium head would cook it's gasket after 10 minutes (in race conditions) which was certainly my experience. I have a TR5 now but I certainly would not use an ally head on a 4 cyl engine again. Hope this helps Regards John Quote Link to post Share on other sites
nramsey Posted October 22, 2006 Report Share Posted October 22, 2006 HiI had a Moss aluminium head on my old TR4 and had a lot of head gasket trouble. I used a solid copper gasket which is arguably harder than the aluminium so may have contributed to the problem. The initial problems were overcome by using a higher torque setting (70lb/ft by Moss increased to 85 after advice). The sprints and hillclimbs were OK but as soon as I got near a trackday ( similar to a race in length ) problems started. I had some lengthy discussions with Jon Wood of Classic Racecraft who reckoned that it was caused by the different coefficients of expansion between a cast iron block and an aluminium head and the head studs having no "give" in them. I believe he had some very expensive waisted studs made up but he is notoriously difficult to contact. Jon said that any engine with an aluminium head would cook it's gasket after 10 minutes (in race conditions) which was certainly my experience. I have a TR5 now but I certainly would not use an ally head on a 4 cyl engine again. Hope this helps Regards John Quote Link to post Share on other sites
MadMarx Posted October 22, 2006 Report Share Posted October 22, 2006 Maybe the use of stretch studs instead of the normal head studs would help. Quote Link to post Share on other sites
jdbinnington Posted October 24, 2006 Report Share Posted October 24, 2006 Maybe the use of stretch studs instead of the normal head studs would help. If head gasket problems are resulting, one would guess because of the extra expansion of ally alloy compared to cast Fe, could a concerted effort to run the engine substantially cooler offer a solution? OK this is layering one compromise on top of another waisted studs could be easily done in a lathe using conventional studs turned down, reduce from say 7/16 to 3/8 dia how about sleeving the stud holes in the head with steel tube inserts... anyway, what is the expected advantage of alloy heads vs. iron ones? j Quote Link to post Share on other sites
marvmul Posted October 24, 2006 Author Report Share Posted October 24, 2006 If head gasket problems are resulting, one would guess because of the extra expansion of ally alloy compared to cast Fe, could a concerted effort to run the engine substantially cooler offer a solution? how about sleeving the stud holes in the head with steel tube inserts... anyway, what is the expected advantage of alloy heads vs. iron ones? j The 4 cyl TR engine has a tendency to overheating problems at the rear end of the cylinder head (4th cylinder) :perhaps, improving the cooling of the rear end of the head can improve the gasket problems. Sadly the u/r waterpump (with six curved blades instead of 4 straight blades) is no longer available through Cambridgemotorsport. If someone knows a source for these pumps (or the impellers), I would be very interested. The weight difference of the 2 head is exactly 10kgs (22 pounds) : 7.5 kg for the alloy head , 17.4 kg for the cast iron head (both inclusive valves and springs) : it's important for a race car, but not for a street or rally car. I've never seen back to back power curves of the 2 heads, I'm told the alloy head should have a power advantage, but maybe that is because it can be run with a higher compression ratio : less prone to knocking because of better heat conduction. But lower combustion heat means lower BMEP... I suppose that alloy heads can easier be modified? I've asked this same question to a lot of people, no one did have a satisfying answer about the power gain with alloy heads. The steel tube inserts in the stud holes is good idea, but since I'm going to fit 91 or 92 mm pistons, the engine block has to be machined anyway and the outer diameter of the sleeves is wider than the standard sleeves : the bores in the bottom of the block( for the sleeves) have to be widened : I'll have the top of the block machined too, in order to get a press fit for the bottom end , but also for the top end. Standard, there is a gap between the top end of the liners and the engine block. I hope the block will not crack by the expansion of the liners. Quote Link to post Share on other sites
MadMarx Posted October 24, 2006 Report Share Posted October 24, 2006 (edited) The steel tube inserts in the stud holes is good idea, but since I'm going to fit 91 or 92 mm pistons,the engine block has to be machined anyway and the outer diameter of the sleeves is wider than the standard sleeves : The 2nd row at the starting grid is not enough for you I suppose What a hell of machine do you plan to build! I have to be satisfied to have the rear end view on your car at future races. BTW...overheating! Have you seen that your registration plate covered half of the radiator air inlet during the race??? Maybe overheating from this? Edited October 24, 2006 by MadMarx Quote Link to post Share on other sites
Guest Philippe Posted October 26, 2006 Report Share Posted October 26, 2006 Dear Chris! When I look at your result in Nürburgring, you should stop complaining about your engine power. Power is nothing without control.... Philippe Quote Link to post Share on other sites
MadMarx Posted October 26, 2006 Report Share Posted October 26, 2006 When I look at your result in Nürburgring, you should stop complaining about your engine power. Power is nothing without control.... Philippe: The dumm thing is, even if I drive like hellhounds are chasing me ...... these Red Baron cars still pull away on the straights......it is furstrating Quote Link to post Share on other sites
marvmul Posted October 26, 2006 Author Report Share Posted October 26, 2006 (edited) The dumm thing is, even if I drive like hellhounds are chasing me ...... these Red Baron cars still pull away on the straights......it is furstrating One podium at the 'Saisonsfinale' was occupied by 3 'Red Baron' drivers : 1st, 2nd and 3rd place : that is an ultimate piece of evidence of the qualities of Jo Willems, the boss of 'Red Baron Garage'. Philippe, I assume you are the Philippe of the green TR4 no 78 car ( pics in another topic of 'TR Competition Forum'): that was a very good performance in the 'Saisonsfinale' Btw: pulling away on the staights is the result of coming out of the bends at a higher speed in most cases! Edited October 26, 2006 by marvmul Quote Link to post Share on other sites
Guest Philippe Posted October 27, 2006 Report Share Posted October 27, 2006 One podium at the 'Saisonsfinale' was occupied by 3 'Red Baron' drivers : 1st, 2nd and 3rd place : that is an ultimate piece of evidence of the qualities of Jo Willems, the boss of 'Red Baron Garage'. Philippe, I assume you are the Philippe of the green TR4 no 78 car ( pics in another topic of 'TR Competition Forum'): that was a very good performance in the 'Saisonsfinale' Btw: pulling away on the staights is the result of coming out of the bends at a higher speed in most cases! Hi Marcel, Indead, I am one of the 3 "Red Barons" (no. 78) and without Jo Willems such a result would have been impossible! Btw: pulling away on the straights....., you're right. Quote Link to post Share on other sites
MadMarx Posted October 27, 2006 Report Share Posted October 27, 2006 ....... in most cases! but not in this one..unfortuntely.... dear god of racing cars, I was always nice, changed oil, checked tire pressures, adjusted all you forced me to adjust.... ...please, please.....GIVE ME MORE POWER!!!!! and if you are deaf I shout: MOOOORE POOOOWER Quote Link to post Share on other sites
marvmul Posted October 28, 2006 Author Report Share Posted October 28, 2006 If two cars are on a circuit and both have exactly the same speed and i.e. they have 20m between them when they are doing 50 km/u in a slow bend, then, on the straight that follows the bend, the distance between them will grow to 60m when they have accelerated to 150km/u. So the second car always sees the first car pulling away on the straights, when he is as fast as the first car. Quote Link to post Share on other sites
MadMarx Posted October 28, 2006 Report Share Posted October 28, 2006 (edited) .......So the second car always sees the first car pulling away on the straights, when he is as fast as the first car. Well explained! So I don't have to worry about at the moment ..... Hope the next races will be as close as at the Nurburgring. Cheers Chris Edited October 28, 2006 by MadMarx Quote Link to post Share on other sites
jean Posted October 29, 2006 Report Share Posted October 29, 2006 Chris the Red Baron philosophy is a very stiff chassis, exellent suspension and good wheel geometry. Too many hp's make the engine unreliable. Don't transform your horsepower in heat, just keep your foot off the brake as much as possible. You have seen on the ring how difficult it is to handle a car with a bad set up, even for Jo Jean Quote Link to post Share on other sites
MadMarx Posted October 29, 2006 Report Share Posted October 29, 2006 Chris the Red Baron philosophy is a very stiff chassis, exellent suspension and good wheel geometry. Will be a hard job for me to find the missing 3 seconds to catch up with the leading TR4...but I'll try my very best! Quote Link to post Share on other sites
jellison Posted November 10, 2006 Report Share Posted November 10, 2006 I spent in developing an alloy head for racer that works about 7-8000 pounds (yes you read that right) and alloy will never work unless some VERY special mods are done, they have all tried RCT, TR Ent, Cambridge, but non will last unless the final few tweeks (not minor my anymeans) are done. Alloy IS best but I have the only one that works. 240bhp from 2440cc!!! Next best is a steel copy of this (as mine was bought new from a blank) and had the valve put in the right places my Mini Miglia Engine Guru's! Marvmul -the iron one you have was on the car when it set the fastest lap of any Tr on the fastest UK track - you should kick but with it - sell the alloy one to a someone with a road car, moderately fast at best (and don't torque to more than 70ft/lbs - iron as you know is 105 - 110. Laters Jelly Quote Link to post Share on other sites
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