Sc drop gear set sound
Discussion
Hi,
I have just started a "newborn" project engine. This is the first time I use sc drop gears.
The engine is developing some horrific sounds. It is like intensive timing-chain-clicking. But if I engage the cluch, it goes away. Is it the normal? I have kept the revs above 2K for the cam-running in, soo I report the sound there. It became much more calm at idling.
Many thanks for any input!
I have just started a "newborn" project engine. This is the first time I use sc drop gears.
The engine is developing some horrific sounds. It is like intensive timing-chain-clicking. But if I engage the cluch, it goes away. Is it the normal? I have kept the revs above 2K for the cam-running in, soo I report the sound there. It became much more calm at idling.
Many thanks for any input!
Sounds like the usual awful nasty straight cut drop gear noise. It is so bad when driving that you will need to use ear plugs on any journey over about 5 miles or you may suffer permanent ear damage (I know because I have 'tinnitus', and it ain't pleasant).
If I didn't need SC drops in my rally car I would replace them with helicals tomorrow.
If I didn't need SC drops in my rally car I would replace them with helicals tomorrow.
Cooperman said:
Sounds like the usual awful nasty straight cut drop gear noise. It is so bad when driving that you will need to use ear plugs on any journey over about 5 miles or you may suffer permanent ear damage
Me? No way! The car belongs to a friend of mine. I told him that it will be noisy, but he insisted on the sc box and the drop gears. Soo, it is normal? I am happy.
camelotr said:
Me? No way! The car belongs to a friend of mine. I told him that it will be noisy, but he insisted on the sc box and the drop gears.
Soo, it is normal? I am happy.
Yes, it's normal. The key to it being the s/c primary gears is that the noise ceases after engaging the clutch (and removing drive to the primary,idler and gearbox input gear )Soo, it is normal? I am happy.
Ok.
I have insalled the engine. Not that bad as I expected. The car has a good level of sound isulation though. Not realy my cup of tea, but still I would say that the sound level is acceptable.
Still I am not 100% statisfied with the result. I have planned a good fastroad engine with good torque curve, and it does not feel that strong as I excepted.
May I missed something? what do You think?
The engine is a 1293ccm unit with 10:1 compression, well ported head with 35.6in (std) and 29.3 ex (rimflow), Maniflow "megafone" exhaust system, KN filter with stubstack on HIF 44, ultralight flywheel, electronic ignition (accuspark), SW5 cam. Fully balanced.
My target was 90 flywheel bhps. But it does not feel like.
Whats wrong with it? Did I expected too much? Is the cam too light for this application? Or?
I have insalled the engine. Not that bad as I expected. The car has a good level of sound isulation though. Not realy my cup of tea, but still I would say that the sound level is acceptable.
Still I am not 100% statisfied with the result. I have planned a good fastroad engine with good torque curve, and it does not feel that strong as I excepted.
May I missed something? what do You think?
The engine is a 1293ccm unit with 10:1 compression, well ported head with 35.6in (std) and 29.3 ex (rimflow), Maniflow "megafone" exhaust system, KN filter with stubstack on HIF 44, ultralight flywheel, electronic ignition (accuspark), SW5 cam. Fully balanced.
My target was 90 flywheel bhps. But it does not feel like.
Whats wrong with it? Did I expected too much? Is the cam too light for this application? Or?
Edited by camelotr on Friday 3rd June 10:59
Edited by camelotr on Friday 3rd June 11:00
camelotr said:
Ok.
I have insalled the engine. Not that bad as I expected. The car has a good level of sound isulation though. Not realy my cup of tea, but still I would say that the sound level is acceptable.
Still I am not 100% statisfied with the result. I have planned a good fastroad engine with good torque curve, and it does not feel that strong as I excepted.
May I missed something? what do You think?
The engine is a 1293ccm unit with 10:1 compression, well ported head with 35.6in (std) and 29.3 ex (rimflow), Maniflow "megafone" exhaust system, KN filter with stubstack on HIF 44, ultralight flywheel, electronic ignition (accuspark), SW5 cam. Fully balanced.
My target was 90 flywheel bhps. But it does not feel like.
Whats wrong with it? Did I expected too much? Is the cam too light for this application? Or?
I have insalled the engine. Not that bad as I expected. The car has a good level of sound isulation though. Not realy my cup of tea, but still I would say that the sound level is acceptable.
Still I am not 100% statisfied with the result. I have planned a good fastroad engine with good torque curve, and it does not feel that strong as I excepted.
May I missed something? what do You think?
The engine is a 1293ccm unit with 10:1 compression, well ported head with 35.6in (std) and 29.3 ex (rimflow), Maniflow "megafone" exhaust system, KN filter with stubstack on HIF 44, ultralight flywheel, electronic ignition (accuspark), SW5 cam. Fully balanced.
My target was 90 flywheel bhps. But it does not feel like.
Whats wrong with it? Did I expected too much? Is the cam too light for this application? Or?
Edited by camelotr on Friday 3rd June 10:59
Edited by camelotr on Friday 3rd June 11:00
Who specced this?
The spec chosen will make 90bhp if built and set-up properly - of that I am 100% sure. But why put it on S/C drops and S/C box? Madness!
The strength of the S/C set-up isn't needed until an engine is showing a torque curve of greater than 90lb/ft. It is a fact that the Austin Metro Turbo (which shares a A+ engine/helical box design common with the Mini) had the boost modulated to peak at 90lb/ft and no more despite the blown A-series being capable of a whole lot more. Reason? Gearbox life and warranty. If you drove a Metro Turbo err "enthusiastically" you'd lunch/destroy the box inside 10K miles. This is as sure as the sun will set tonight and rise tomorrow morning
Back to your engine build - The S/c drops are the major conributor to the noise and the power of the engine doesn't warrant the use of them. It won't put enough torque into the idler set-up that will result in a damaged drop gear housing.
In short, he's deafening himself for no apparent reason
Pardon?
I fitted s/c drops to my small bore as it was just a weekend car and my bit of fun. I love the noise and the attention it gets, the looks on peoples faces as you drive past is comical and dogs seem very confused also!
YouTube Link to my S/C drops
http://youtu.be/Vwqiz_unmvI
YouTube Link to my S/C drops
http://youtu.be/Vwqiz_unmvI
FWDRacer said:
Who specced this?
The spec chosen will make 90bhp if built and set-up properly - of that I am 100% sure. But why put it on S/C drops and S/C box? Madness!
The spec is mine. A friend of mine has a neverending-project-mini, and he wanted afastroad engine peaking below 6K with as much strenght as possible. Soo did I concluded in this setup. The sc box/gears was only for fun.The spec chosen will make 90bhp if built and set-up properly - of that I am 100% sure. But why put it on S/C drops and S/C box? Madness!
I set the engine today with wbo, and it looks like it runs spot on eith the metro turbo BDK needle. ? Strange. I assume it is a lot of fuel, and the engine burns it at afr14.6 on the whole range up to 5k. Acceleration is at afr 11.5-12.5. Just about perfect. donno.
To have SC drops without always using either a crash helmet or ear plugs is plain madness.
I now have severe Tinnitus and I can tell you that it is misery. Permanent noise like a jet engine in your head 27/7. Never a quiet moment - ever. It never goes away and there is no cure.
SC drops are for competition use only.
I now have severe Tinnitus and I can tell you that it is misery. Permanent noise like a jet engine in your head 27/7. Never a quiet moment - ever. It never goes away and there is no cure.
SC drops are for competition use only.
Ive got SC drops and SC gearset in my '61 car - no soundproofing, no carpets.
having driven from Scotland to the 'ring 3 times, and the last 6 London to brighton's (each an 1100 mile round trip), all with the "noisy" gearbox, I cant say my hearing is in any way affected - done 1500 miles in the last 2 weeks in it.
but back on topic -
my engine spec is about the same as yours, (1312cc and have 1.5 roller-tips on mine) 90 bhp is possible with very careful assembly, but if you want something stronger, you really shouldnt have chosen the SW5 - its a fabulous road-cam, but runs out of puff a bit early. Im about to change mine for something a bit more potent - I will miss the lump of torque at 1500-2k, but after 6 years of hard use, its time to revamp with some more extreme engine components and head for the magic 100bhp.
incidentally, what FD ratio are you using? gearing the car correctly for the use will make a substantial difference to the way the car feels - Im on a 3.2 diff - probably shouldve fitted the 3.1, but my gearing on 10" rims is about perfect for the engine spec, without making it all too frantic on the M6 at 70 mph for the 7 hours it takes me to get anywhere.
having driven from Scotland to the 'ring 3 times, and the last 6 London to brighton's (each an 1100 mile round trip), all with the "noisy" gearbox, I cant say my hearing is in any way affected - done 1500 miles in the last 2 weeks in it.
but back on topic -
my engine spec is about the same as yours, (1312cc and have 1.5 roller-tips on mine) 90 bhp is possible with very careful assembly, but if you want something stronger, you really shouldnt have chosen the SW5 - its a fabulous road-cam, but runs out of puff a bit early. Im about to change mine for something a bit more potent - I will miss the lump of torque at 1500-2k, but after 6 years of hard use, its time to revamp with some more extreme engine components and head for the magic 100bhp.
incidentally, what FD ratio are you using? gearing the car correctly for the use will make a substantial difference to the way the car feels - Im on a 3.2 diff - probably shouldve fitted the 3.1, but my gearing on 10" rims is about perfect for the engine spec, without making it all too frantic on the M6 at 70 mph for the 7 hours it takes me to get anywhere.
Mrtee said:
but back on topic -
my engine spec is about the same as yours, (1312cc and have 1.5 roller-tips on mine) 90 bhp is possible with very careful assembly, but if you want something stronger, you really shouldnt have chosen the SW5 - its a fabulous road-cam, but runs out of puff a bit early. Im about to change mine for something a bit more potent - I will miss the lump of torque at 1500-2k, but after 6 years of hard use, its time to revamp with some more extreme engine components and head for the magic 100bhp.
incidentally, what FD ratio are you using? gearing the car correctly for the use will make a substantial difference to the way the car feels - Im on a 3.2 diff - probably shouldve fitted the 3.1, but my gearing on 10" rims is about perfect for the engine spec, without making it all too frantic on the M6 at 70 mph for the 7 hours it takes me to get anywhere.
Our fd is 3.2 just like Yours. I intended to fit a lower, but my friend wants to do hightway drives. The engine was assembled carefully - at least as I assume. The cam was timed in 108degrees, all clearances checked etc.my engine spec is about the same as yours, (1312cc and have 1.5 roller-tips on mine) 90 bhp is possible with very careful assembly, but if you want something stronger, you really shouldnt have chosen the SW5 - its a fabulous road-cam, but runs out of puff a bit early. Im about to change mine for something a bit more potent - I will miss the lump of torque at 1500-2k, but after 6 years of hard use, its time to revamp with some more extreme engine components and head for the magic 100bhp.
incidentally, what FD ratio are you using? gearing the car correctly for the use will make a substantial difference to the way the car feels - Im on a 3.2 diff - probably shouldve fitted the 3.1, but my gearing on 10" rims is about perfect for the engine spec, without making it all too frantic on the M6 at 70 mph for the 7 hours it takes me to get anywhere.
The car left the day before yesterday. The guy hasjust informed me that the idle has rised significantly, and the engine seam much more willing. Did any of You experienced significant powerrise after running in? The car now has about 500kms on the clock with the new engine.
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