Engine 1st Gen Most liked posts in thread: Next step in my Modding

I have not gotten to the point that I cannot remember what I said 5 minutes ago, but that time is coming.

 

I have a R52 JCW - RS. A very special MINI that handles better, goes faster and stops quicker than any GP1, plus it has a drop top.

Don't worry we that have drop tops still associate with you that do not.

 

Hand porting worked for many years, yes a computer controlled machine is going to be more precise and steady but if that it is all life is about than the likes of Shelby, Foyt, Yates, and numerous others that were mechanics such as the guy that created the below, mean nothing.

For me, just because something is old or is produced by old means/methods, does not mean it is worthless.

 

Agree with everything said and if I was looking to compete with my car I would go the CNC route. There is a cost difference and with the TPR2 head, a ported intake manifold can be added and the total is still less than the RMW.

When I start a thread it is not a "this is what you should do" but rather "this is what I do." Anybody wants to go the CNC route, have at it, no problems here at all.

 

All this discussion leads into more detailed discussions on the head, valves and camshaft. I created a thread that has some basic information on these engine components along with some web supporting articles and videos.

https://www.motoringalliance.com/threads/talking-heads.30840/#post-408729

 

There are some good threads on Thumper heads over on the side of the Pond. 1320 is a British Tuner that apparently has done allot of tuning on all of Thumper's heads.

I had Jan at RMW tune my car when I installed his cam and 450 injectors. Since that time I have gone to a 19% pulley ratio, a header with a 200 cell cat and meth injection system that I am not using for tuning but rather cooling the intake manifold temps from the 19%. Any of the larger valve heads have different valve springs so the Rev Redline can be increased. The issue with increasing the Redline is that will there be a point where an injector may have a maxed out "duty cycle" and with the 450's that is probably more than a possibility.

The 19% provides better low end torque but at higher revs the heat developed can cause premature detonation. IMO I addressed that for my driving habits by installing the Meth injection. I keep stressing that I am not tracking or do autocross.

To get the most benefit from the larger valve heads you need to push that redline but I am not into bragging rights and to push the redline it might be best to remove the 19%. The 450's duty cycle also come into play here so at this point I am thinking about leaving the redline at 6,750. I will still get the benefit of more torque and will not be pushing the supercharger even more. I have my ultra gauge set to monitor the O2 voltage outputs. On this subject, a voltage of .045 is equal to a F/A of 14.7:1, a 0.1 is lean with 0.9 being rich. Remember that the OEM O2 are narrow band sensors and do not provide Lamda outputs.

Jan did the tune for the cam and injectors and it would appear the ECU can address the additional air flow relative to A/F. I plan on logging the O2 voltage prior to the swap and then will watch it when I have the new head installed. What I see will determine whether I pursue another tune. I push redline in 1st gear and then in 2nd on mountain runs. I will hit the limit in 1st but have not in 2nd. The 19% will address low end torque, the head will increase the total torque and the horsepower will also be increased. Tracking would expose the supercharger to long durations of high rpms and also result in higher intake temps. The instances of doing this on my spirited mountain do not exist and the loss of any top end hp due to lover revs is not going compromise the fun I am having.

 

On pulleys, here are some spreadsheets that reflect pulley ratios, motor rpms and supercharger rpms.

 

When I start a thread of this nature I always hope that some good discussions result and that is just what is occurring. I am not into asking somebody what color of car I should purchase or whether I should use all-season tires. There are some very informative posts here. How many people when thinking about a head change also realize that injector size and fuel pump pressure/volume are going to be involved?

I have spent allot of time around MINI forums over the past two years and cannot remember seeing current good discussions on these type of matters. The Gen1 is a car that was developed almost 20 years ago. Technology has not stopped in that time so many older posts on any of these types or issues are loosing their relevancy.

 

So which Thumper head did you buy?

 

Thanks for replying as actually trying to get some real consumer type thoughts from those that have had either let alone both is so much better than just opinion.

From @BlwnAway it appears he had both heads. He also had the cam gear that Thumper Heads sells. Thumper will time the gear for you as well.

 

From what I have been able to find it appears the torque curve of my RMW Dominator cam starts around 2200 rpms with the OEM valves. The bigger valve heads will push that value up more toward 3000 but it also appears that if the cam timing is changed just a little with a cam gear I will be able to get the torque back down toward 2500 rpms.

I am not planning to increase the redline at this time. My type of driving benefits more from torque than HP at higher revs. I talked to Thumper and he thinks he can tweak the Dominator with his Cam Gear to get me down to 2500 when it is matched up to his TPR2 head.