3 replies to this topic

[diogoteix]

Hello guys,

 

I just ordered a MED "Trackday" 7 port head to upgrade my 1380cc Mini.

I use it every day, in Lisbon, so I don't want a pure racer. In fact a really need a lot of torque because of the straight-cut box / 3.44 diff fitted (1st gear on a SC boxes is really long), and because Lisbon is one of those "7 hills" cities (we even have the same bridge and cable cars as in San Francisco...).

So my dilema is the following:

- keep my SW5-07 cam

- swap for a RE13OT cam, hopping that the 7 port head boosts the torque enough to make for the significantly higher valve duration (276º instead of 242º...)

 

I take the opportunity to leave here the specs of various cams (always difficult to find them so, here they are!):

Swiftune SW5
Checking height @ lobe: 0.016"
Timing (IN/EX): 16/48 52/12
Nominal lobe lift (IN/EX): 0.281" / 0.281"
Duration (IN/EX): 244 / 244°
Lobe centre angle (IN/EX): 106 / 110
Lobe separation angle: 108.0
Lift on overlap: 0.036"

Swiftune SW5-07
Checking height @ lobe: 0.016"
Timing (IN/EX): 10/52 47/15
Nominal lobe lift (IN/EX): 0.286" / 0.286"
Duration (IN/EX): 242 / 242°
Lobe centre angle (IN/EX): 111 / 106
Lobe separation angle. 108.5
Lift on overlap: 0.0385"

SW10 spec
intake 34/66
exhaust 70/30
duration inlet 280 exhaust 280
lift intake 0.291" exhaust 0.291"
lca inlet 106 exhaust 110

Dixit Keith Calver: "The cam specs I will pass on are as follows. Though these are for the RE13OT. The only difference is the lobe separation angle (105.5 deg on the RE13PP) and therefore the lift on over-lap is less"
*RE13**OT*
*Checking****height:* 0.016" @ lobe
*Timing:***(Intake): 34.5/61.5 (Exhaust): 63.5/32.5
*Nominal****lobe****lift:* (Intake): 0.290" (Exhaust): 0.290"
*Duration* (Intake): 276 (Exhaust): 276
*Lobe****centre****angle* (Intake): 103.5 (Exhaust): 105.5
*Lobe****separation****angle:* 104.5
*Lift****on****overlap:* 0.085"

 

[Orange-Phantom]

The 7 port head does increase the torque which means you can get away with a wilder cam than on a 5 port.

 

From what other people have said on here they find the SW-05 a bit tame if not a good standard cam replacement, I cannot comment on the Calver Spec cam, a-lot of people have good results with a 266 or 276 Kent Cam.  With the 7 port the 276 may be a better all round option.  Good drivability and good power.  I would suggest contacting MED to get their advice or AC Dodd also make his own profile cam's and again I would recommend having a chat with him.

 

I've got a SW-10 (comparable to a Kent 286) in mine which is great fun but I probably wouldn't recommend it as a daily driver.  The cam only properly starts working from 2,800 with excellent power from 5,500 http://www.swiftune....t-camshaft.aspx.  It's fine when cruising and pottering about below 2,800 but if you want power you have to rev it above 2,800 otherwise it will bog down.  This also being down to the fact that it is a 7 port and the gas flow speed through the head is probably a bit too low below 3,000 rpm.

 

Remember you have just bought a 7 port head and are not going to realise it's true potential by restricting it with a low down cam, but then you'll have to make a compromise with it's performance lower down the rev range.

[diogoteix]

Thanks for your comment, it took me a while to see your answer, but in fact I pretty much followed your advice.

I've chosen the RE13OT from Calver for 2 reasons: it's the cam chosen by Specialist Components on one of their first implementations of a 7 port head (with very good results), and they are OK to grind their profile from a standard MPI camshaft that I purchased on Ebay, which means that I will be able to set a camshaft sensor and use a sequential injection setup, better for low RPM and idle fueling. The RE13OT is not as wild as the SW10 with 276deg instead of 280, and LCA of 104,5 instead of 111/106 (In/Ex). So usable power is supposed to start at a RPM of 2000 instead of the 2800 you mention, which is more in line with a day to day usage.

As for MED, just as Swiftune, they kind of lack any intermediate cam, jumping from an equivalent of a SW5 (their MED H/T which is 256º duration) to their MED XTR which is supposed to start working at 3000RPM...

 

Can you tell us what results you obtain from your setup?

[giannoutsos]

Hi everyone, I just purchased a RE13 pp cam is the only difference between this an the OT the lca can you time it at 104.5 and make it a OT? Wouldn't it be lumpier?
Also anyone has used this in a port, results, megajolt map?
Thanks in advance
John