x2. What set-up would maximize torque/drivability within the 3,000 to 5,000 rpm? Would the WMS head still have a sweet spot in this range? Would a custom build be required? Or, should something else be tried instead of a head? Also, what collateral bits (injectors for example) would be needed? I already have a 17% reduction pulley and am about to pull the trigger on a CAI (probably Dinan) and a cat-back.

 

"Thanks Obe..... this is a big help expressing my thoughts...." sayeth Spiderx.

DITTO. I want low-to-mid-range. I've got a daily driver that rarely sees the sunny side of 5k, much less 6 or 8. I'd eventually get arrested here in the big city if I stayed on the throttle long enough to get that high in revs. We don't have an autobahn. But I'd surely love to make those muscle cars' drivers' jaws drop open on occasion.

 

I understand the "drivability" factor. However, I believe we need to define drivability.

Let me back up; we all remember the intro of the twin charge and the "drivability" speculation surrounding it. In reality, the (I don't know the real power #'s, nor care) 400hp it was putting out, didn't so much affect the drivability, as it was still drivable, but how the person driving it modulated the power output.

So what kind of drivability are we talking about? I understand the balance of power; to make more at top, you'll lose some down low, build here-loose there, etc. So deciding on a optimum spec for use seems critical.

An illustration; the mag. EVO (don't remember the issue), tested stock MC/MCS vs JCW spec'd, vs other tuners. In the test, the stock cars nearly outperformed their counterparts. However, the testing can be questioned, as the 1/4 mile may have exploited the JCW benefits up high, or the skid pad favored the torquier bottom end of OEM. (My issue was lost in a move, otherwise I'd develop this more with actual data in relation to test criteria and specific instances, mods, etc.) But in the end, each car remained "drivable."

So what benefits can be had/lost in relation to porting, valve size, spring, rpm range, etc (come on spec it out)?

I'm tring hard to word this in a way that educated responses can be posted without loss of secrecy.

And on a specific note, where does the Cooper's Schrick cam actually lie in the heirachy (as far as aggressiveness for street, drag, race)? What are OEM cam's #'s anyway? I'd like to be able to compare stock, vs mild, medium, and hot.

 

nice post....good questions

 

in the relatively short usable rpm range of the mini (1-7K), I have yet to see ANY mod that increased hp and at the same time showed a torque curve that dipped below the stocker anywhere.

 

PROPRIETARY?? That's BS, it's a machine shop not bio-tech, if a machinist doesn't want to tell me what he is doing to my parts, and why, then there is no reason to hire him.

 

knowing what i know about R&D and products much more sophisticated than this..... I find it hard to disagree......

racing is a relatively small market and the secrets are like a football teams "playbook".... of course you don't give out the teams "plays"....these (heads) products are for "quasi mass market" if you want customers other than the people who can see/reach you directly you need to give up some "features and benefits".... otherwise you are asking for a lot of faith...some may be willing to "leap"....

 

At the end of the day this is an open community specifically to share information, expreriences, ect.... and we all have the option to participate in a thread or not. As well, we all control what we post or say.

Got a secret don't wish to share try this just don't post as opposed to posting that you can't talk about it.

 

I wonder how many of the vendors yakking about head porting secrets actually do the work themselves, or is it done even in their own shops?

 

I repeat, it's machine work from a machine shop or hand filing and sanding or both, never has been any more complex than that, bigger numbers and a change in the "curve" and lap-times tells you the results.

 

Torque and Hp = It all boils down to this, improve CMF to the highest velocity with the lightest moving componets and that sums up the mechanics of that. Improve combustion camber effiency which is composed of head camber area and piston crown as a unit. Taking all this into consideration to arrive at an improved flame front to enable more complete combustion without detonation. Remember the reason for porting is to get fuel/air charge in and exhaust gas moving out and this can work for/against what is going on in the combustion camber. Combustion chamber effiency is key to power, thats where fuel/air are converted to heat energy.= power
Just my .02

 

nicely done..... so what combination works best in a Mini (no mods...few mods...lots of mods)

 

Obvious... lots of mods

What stops one from say a "race" spec head and using a cam to optimise for street? You would already have an extremely high flowing head. Its not going to flow more than the cam will let it.

So how would this "race" spec stack against availible cams (oem, mild, race)?




...lemme guess: OEM-not much benefit; Mild-more between 3k to redline; Race-more aggressive 4k up than mild.

 

It has been my experience that you will not lose drivability anywhere in the range - my head wasn't tested in the EVO article BTW.

Can I make more power up top with specific changes? Absolutely. Can (and do) I make more power in a more "drivable" range for a street car? Absolutely. It is done with the porting and cam specs.

I'll dig around for the specs on cams - I know I have it all, as I gave all the info to El Diablito a while back when he was looking at making his own cam (I think for Fireball maybe).

I hope I have offered all the info needed on our head and where it makes its flow numbers and what that relates to. If you need more info, just let me know.

Hope that helps!
Randy

 

I guess to be more specific... is there a spec where unless you have this or that you will not get the full benefit... you should do something else Boolean logic... if then go to stuff..... for example if you are never going to do a header does it make sense to get oversize exhaust valves... what about "decking" what are the parameters that are used n making those decisions that people can count on when making their choices... after that you match your "goals" to the mfg who has the closest to what you are looking for.....etc.....

let's use Don's statement as an example..... he says he does custom heads.... well what are the parameters for his choices..... if one size does not fit all then how does one make an "educated" decision....

this is not that hard.....

 

I don't think it's that hard, Bob, there's just a lot of info to cover.

For us, (as you know), we find out what the car will be used for. If it is a race car that rarely sees the street or the other way around. To be honest, most guys doing the head already have the other mods in place - the intake, pulley, header, and exhaust - in fact I don't remember ever doing a head on and otherwise stock car.

I would recommend doing the intake, pulley, header and cat-back then going for the head unless there are other circumstances (schedule of install, cash, etc).

The bottom line is, every single customer is different in both part and install needs. The reason I spend so much time on the phone and on writing responses is to make sure we are getting those needs taken care of. I am VERY confident we can get each customer exactly what they want.

Hope that helps!
Randy

 

Good head at a reasonable price?

Still talking about a cylinder head.

 

Back to readership opinions; the benefits of the stock camshaft are many. The camshaft was designed to account for varying fuel quality around the planet, fuel economy, use in both NA and FI applications, and let’s not forget designed for the MINI’s valve train. A stock camshaft that has been worn-in with a particular head has correctly mated races; no small matter for long term wear characteristics. I had someone that designs camshafts, profile the stock cam, he also profiled the Schrick cam, and his analysis was similar, OK but not the best from his perspective for FI use. The Schrick received lower marks on ramp slope for valve train wear. Camshaft materials should be considered also and machined from billet is not always optimum; don’t ask me to explain that one because although I comprehend the concept I can’t put it into words. Someone asked about what they would give up or where the trade-off would be in a modified head and that would be when a narrow focus designed camshaft is placed in the mix.

When MINI head work is well executed the gains are across the board. Time and pressure may change relative to rpm but increases in efficiency will still be as relevant at 2,000 rpm as it is at 6,000. Any improvement over factory casting legacies will have a positive impact; a case in point is the JCW head. Greater gains come from skilled bowl shaping, optimized port geometries, valve angles (it really isn’t a secret that any angle that is less an angle and more an even transition is good for flow) and although the DYIer can see improvements with conservative shaping, it is best to leave this to a skilled professional. Not all head work can be evaluated using cfm measurements. Quality of flow is important and I for one do not understand that data or the tools used to measure it. Another reason to choose a professional that utilizes measurements of that type and knows the real world (on the street or track) outcomes. This is the area where a leap of faith is important. The good thing about having to make a choice whenever it comes to that is, you can not go wrong with any of the choices offered by vendors on this site, even if they don’t actually do the work themselves it is performed by a skilled professional. My personal recommendation irrespective of his services not offered on NAM http://www.theoldone.com/components/...ead_modifi.htm

All this bolt-on stuff is a touchy subject with vendors; after all it is their bread & butter. The fact is MINI didn’t leave that much in performance on the table with intake and exhaust design. A modified head will still make power with the stock intake and header in place, a little more with the aftermarket bolt on stuff, but not that much more. Camshaft and aftermarket header combo, some, overdriving the M45, yes, that is a proven without contradiction. Some other improvements can be made in the intake and exhaust route with some hand work only, without relying on bolt-ons.

 

And, what yields more torque at lower and wider rpm ranges? Gotta love the armchair pontificators....

 

how many cam grinds typically can the tuners say they've gone thru to get to the product they're now selling ? anyone ?

 

what i mean is ...can you imagine the work involved in doing a grind ,then installing then dyno, then another and on and on .at some point you gotta say sell it now .

 

What has been maximized here? I don't have two heads to compare, but anyone feel free to post theirs.





Sorry for the huge pics, but detail is essential here.... <hint><hint>

Speaking of cam grinds; reprofiling a stock cam to suit needs, wouldn't reshaping change tolerances (ie lift, duration) that would have to be readdressed in the valvetrain (extending, etc.)? What are the benefits/downfalls to a "regrind," vs. a "cast" (I don't know the specific word I'm looking for here, but a cam that doesn't loose any metal)?

 

well that's me being general . you can grind to open quicker or less . but yes recast or forge is the way then the grind comes in . it's as we say here in mass. wicked expensive.

 

i like the way the valves angle away from eachother making almost two chambers in one .

 

Ok ... we finally have some momentum.....thanks to all keep it going as I think the door is open and the party is starting