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what camshaft profile would be... https://www.ausmini.com/forums/viewtopic.php?f=5&t=92199 |
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Author: | deluxe67 [ Sun Mar 27, 2016 2:31 pm ] |
Post subject: | what camshaft profile would be... |
appropriate to achieve the quickest 0-60 mph performance? Any thoughts? |
Author: | Morbo28 [ Sun Mar 27, 2016 3:40 pm ] |
Post subject: | Re: what camshaft profile would be... |
It would really depend on your engine specs. Capacity. Torquey stroker vs 9000rpm. Tyre grip - can it handle being driven off the line at peak power. Diff and gear ratios. |
Author: | deluxe67 [ Sun Mar 27, 2016 6:53 pm ] |
Post subject: | Re: what camshaft profile would be... |
Hi Morbo, Most of the specs are in my profile. To add, highly modded head, big valves etc. FD is Mini K, 3.7:1 I think. Rockers are standard. Gearbox is close ratio. With current cam has loads of torque down low. As it's set up will do 90 km/h in 2nd but don't know at what rpm. Don't want to go there again because it hasn't been dyno tuned. Engine has to come out due to minor gearbox problem that's why I'm asking about cams. I think my current cam is a bit boring... |
Author: | MiniVLT [ Mon Mar 28, 2016 10:37 am ] |
Post subject: | Re: what camshaft profile would be... |
I think another question you have to think about is what is your REV Limit? and what are you going to rev it to? Also, what is your driving style, daily, weekend warrior or track day? Your probably aware that some cams run out at 6500 others at 7000, 7500 and so on. Which also means they don't start to make power until 2000, 2500, 3000 and so on. The MG Metro cam I believe was one of the their better BMC cams of the time, but now a days there are much better cams kicking around. Gr's 266S and RE83 have great low down torque but will run out of puff by 6500 or so. His RE13 is somewhere between 2000 and 7500 with more mid and topend. MD286 is the most guys will run on the street and traffic can be quite a pain to drive it in. Cheers Shane |
Author: | drmini in aust [ Mon Mar 28, 2016 12:24 pm ] |
Post subject: | Re: what camshaft profile would be... |
Graham's RE282 (original) gives peak power (with 1.5 rockers) between 7000-7200 and is quite drivable down low. I can pull away from 40kmh in 4th without snatching, at part throttle. The 45 Dellorto has 36 chokes in it. It takes full throttle from 2700 and cam gets a second wind @ 4800. Revs to 8000 but I now have an electronic cutout @ 7500. His newest RE282 is a bit lumpier though, he says. His RE286i even more so. Depends how much of a dog you want it to be in traffic.....! |
Author: | mickmini [ Mon Mar 28, 2016 12:55 pm ] |
Post subject: | Re: what camshaft profile would be... |
drmini in aust wrote: Graham's RE282 (original) gives peak power (with 1.5 rockers) between 7000-7200 and is quite drivable down low. I can pull away from 40kmh in 4th without snatching, at part throttle. The 45 Dellorto has 36 chokes in it. It takes full throttle from 2700 and cam gets a second wind @ 4800. Revs to 8000 but I now have an electronic cutout @ 7500. I love this cam. Shame that Kev an I are the only ones who get to enjoy it! 3d gear through the fishhook at Wakefield park no problems. |
Author: | drmini in aust [ Mon Mar 28, 2016 9:54 pm ] |
Post subject: | Re: what camshaft profile would be... |
mickmini wrote: I love this cam. Shame that Kev an I are the only ones who get to enjoy it! 3d gear through the fishhook at Wakefield park no problems. Graham made another master from an unworn 282 cam, so he can grind them still. I have one down there at the moment for a regrind. |
Author: | mickmini [ Tue Mar 29, 2016 12:38 pm ] |
Post subject: | Re: what camshaft profile would be... |
drmini in aust wrote: mickmini wrote: I love this cam. Shame that Kev an I are the only ones who get to enjoy it! 3d gear through the fishhook at Wakefield park no problems. Graham made another master from an unworn 282 cam, so he can grind them still. I have one down there at the moment for a regrind. Awesome. But I kind of liked the exclusivity |
Author: | drmini in aust [ Tue Mar 29, 2016 2:19 pm ] |
Post subject: | Re: what camshaft profile would be... |
mickmini wrote: drmini in aust wrote: mickmini wrote: I love this cam. Shame that Kev an I are the only ones who get to enjoy it! 3d gear through the fishhook at Wakefield park no problems. Graham made another master from an unworn 282 cam, so he can grind them still. I have one down there at the moment for a regrind. Awesome. But I kind of liked the exclusivity Well, GR also has one in his 1400 stroker LS.... and it made near 140HP @ the crank with a single HS6 on the engine dyno..! I bet it's got a bloody good head though. |
Author: | TheMiniMan [ Wed Mar 30, 2016 8:48 am ] |
Post subject: | Re: what camshaft profile would be... |
the way cams "Act" really depends a whole heap on how big the engine(bore) is for example a wade/tighe 140 (35/75-ish) is almost smooth as silk, soft as a baby`s bottom in my 1510cc, barely a lump to be had on idle & i can wide-open-throttle it at approx 1200rpms in top gear. BUT!!!,,, shove that very same cam into a little 1293 & you basically have a bit of a pig to drive around town ,,, but pretty damn good little rally cam all the same. great mid-range with a fair bit up top,,, but still no full-race thing either. now,,, lets stick that same cam into a little 850 & you have an absolute pig to drive around town, so0000 not street driver friendly at all,,, & lumpy as sh!t... & no-way could you "wide-open-throttle' that thing anywhere near 3000rpms-ish. Bore size has quite a lot to do with cam selection so does the use of the car so does your "Want" for lumpyness & acceleration & revs etc. Horses for courses this goes with that at Susan etc if it`s for the street, i recommend a mild street cam (funny enough) if it`s for track days & occassional street, then i recommend a "rally-ish" cam (lots to choose from) if it`s all for the Race track only then grab a decent full race & run the high compression & use Av-gas & you`ll need a sc/cr gearbox , light flywheel , heavy clutch, big inlet, big head, big exhaust etc etc etc again & simply--> "Horses for courses" i do (however) like to slightly "under-cam" our engines just a tad,,, find a series or selection of cams around the driving you want to do & pick one slightly smaller that you "Think" you need... but make sure you "spring" your valve springs to suit under sprung & you`ll end upo with float & then bounce & possible "Bang" (or atleast hammered seats & valves & will need re-newing before it`s natural time over springing & you`ll have a much slower engine, lots of wear & tear very early in the peace. so much to think about hey? i`m off to a funeral cheers Matt |
Author: | deluxe67 [ Mon Apr 04, 2016 9:37 pm ] |
Post subject: | Re: what camshaft profile would be... |
Thanks for all the replies. The RE282 seems to be the appropriate choice? GR would you care to comment please? Thanks Mikal |
Author: | GR [ Tue Apr 05, 2016 6:43 pm ] |
Post subject: | Re: what camshaft profile would be... |
Hi Mikal The 282 is a really good cam it is about as big as you want to go for a road cam, we use this cam in race cars hill climb, track days and rallies,just remember that any cam above 270 duration will not make peak torque till you reach 5000/5500 RPM and peak HP at 7000 to 7500 RPM with the right head and carburation, my RE13 will make HP to 7500 RPM the right goodies,Yes they will pull away from lower RPM on light throttle but they will not get there bum into gear until peak torque. You say you have a close ratio gear box is that a STD "S" box? you must take into account the RPM drop in gears, I think the Cooper S box has drops of about 2000 and 1500 may be higher in some gears I just forget exactly what they are, the thing is you have to rev it high enough so when you change gear you get back into your peak torque to accelerate the car. That's why the British 2 litre touring cars had there peak torque and peak HP 750RPM apart with 6 speed gear boxes and very close ratios, but to answer your question the 282 is a really good will make a lot of HP with the right gear and will run to 8000 RPM . Graham Russell |
Author: | deluxe67 [ Tue Apr 05, 2016 10:34 pm ] |
Post subject: | Re: what camshaft profile would be... |
Thanks GR that clarifies things somewhat. Just to be clear, the car will be a weekend car with maybe the occasional hillclimb. I won't be doing any city/ traffic driving in it. I'm looking for a package that will be fun with a few thrills to go with it. The cylinder head (heavily worked) was built to cope with a big camshaft so the 282 cam should work well I think. I don't have the gear ratio's to hand but believe they are very similar to Cooper S spec. Thanks for all your ideas. M |
Author: | Besser [ Wed Apr 06, 2016 4:30 pm ] |
Post subject: | Re: what camshaft profile would be... |
Maybe a dumb question, caming and compression ratio. How does compression ratio effect cam selection (not the other way around)? |
Author: | MiniVLT [ Wed Apr 06, 2016 7:24 pm ] |
Post subject: | Re: what camshaft profile would be... |
The longer duration and more overlap that a cam has the more compression ratio the cam requires to work properly! Std cams use 9.5:1 - 10:1 whereas race cams use 12:1 - 13.5:1, depending on what fuel you are running too. Cheers Shane |
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