When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Is the car running good now? the two mods that will add the power ( other than a tune ) IS the head or camshaft. Both in the conservative size will add power and NOT need a tune. 25-35 WHP is do able with the stock parameters in your current ECU. Any person that tunes can and will tune your engine. There are no tricks here. I have been told the Mynes Bytronics are better over the RMW, and then vice versa on the RMW vs Bytronics. Myself ? Bytronics. . Get a Head off Thumper Performance TPR1 or TPR2, and now they have some good camshafts. .410/.374 drop in HP or a .405 / .371 drop in HP. And if you need a tune, anyone can do it for you. You should be in the 220-230 HP before the tune.
If Thumper and Bytronic are so good, how come neither of those parts are on the highest HP MINI?
What I find amazing is how differences in dimensions that many people would never even consider can make a significant change in how an engine performs. I got my Thumper TRP 408 cam today and as I also have an oem cam laying around I put them side by side.
These pictures may not do justice to the obvious visual differences. The oem is on the left and the TPR 408 is on the right.
I can see a height difference in the intake lobes.
The exhaust lobes have what I would call a wider crown whereas the side angles are steeper that means the top portion is wider.
I can also tell that the lobe separation is wider (larger angle). You should be able to see that lobe on the left side does not seam as large as it is turned more under.
Many times you will see a cam expressed in numbers presented as xxx/xxx for a single overhead cam engine, SOHC, as we have in our Gen1 MINIs. In this instance the first number is the intake value and the second is the exhaust value. This can become somewhat difficult as some manufactures will either include or exclude the "rocker arm ratio" in their lift numbers. The rocker arm is like a teeter totter/seesaw whereas the distance from the center pivot point increases or decreases the travel distance. This is similar to a lever and fulcrum. For the Gen1 the Intake Rocker Arm Ratio ,RR, is 1.64 and 1.44 for the Exhaust. The "lobe lift" value of the cam would be multiplied by the RR to obtain the total "lift".
In other words you may see a R53 Cam expressed as either .203/222 (without the RR factored in) or .333/.320 (with RR).
Next it appears the Intake Duration for the Stock Cam is 244 with the Exhaust at 255. With the information of the second video above and now with both the valve lift and cam duration know there should be a better understanding on the Newman Cam Chart below. This chart can be seen here and then go to the second page.
Newman has six different cams for the Gen1. A review will reflect that Newman says where the Power Band should be, the "Duration" for both Int/Exh, the Valve lift which is the cam lobe lift increased by the RR, the cam lift which is only the lobe lift, along with some Timing and Full Lift values. Base upon the Stock Cam durations, the PH1/2 is the closest to the Stock Cam relative to duration but a closer look reveals that all the Newman Lobe Lifts are anywhere from 20% to almost 42% on the intake side.
Next post will be where I asked Mike Schultz some specific questions.
This chart appears to reverse lobe lift?? Given intake RR at 1.64 and exhaust at 1.44 their valve lift numbers are off. Take ph 1/2 as an example. You can't get from the charts lobe lift to valve lift without reversing something.????
Yep, they are aware and are going to correct this when their new year catalog comes out. Seems they used the 1.64 intake rr for both lift numbers. Go off the lobe lift .
shopping around for a cam on my future track car build, anyone know how the grand am compares to the catcam 469 and thumper 408 ? I am planning on running ecu master black stand alone, and I would like to retain stock JCW head & 7K rpm limit for the moment. Currently running a dominator on stock ECU.. Eventually the car will receive rods & bvh but probably not this season.
Brake vacuum is obviously important, some HPDE club inspections even check for vacuum issues at the annual tech inspection.
Seems that this was a long time ago. Today it seems to be more important, as there seems to be a lot of OEM cams with the lobes worn and Drivers are looking for replacement camshafts. Good Read !
01-01-2019, 03:01 AM
