Mth,
Do you have a map for high RPM's, if not can you or are you designing one? This thread is what sparked my interest.
https://www.northamericanmotoring.co...ad.php?t=55748

Thanks!! -- Johan

 

 

Holy crap..thats all i have to say about that. 8,000 plus RPMS out of STOCK components? How much more power is available past 6750?

Also, im not going to ask this that forum; but what is "valve float"? I understand the basic components of engines and valve springes, etc, but I have never heard this.

 

It happens eventually when your cam shaft is spinning too fast and your valves literally start hovering/bouncing out of contact with the cam. In our cars, it does not happen until past 8k, perhaps even 8.5k, hence 8k is safe.

When it does happen, and you keep your engine in that region, you risk troubles like valves falling through and fouling the piston. Again, it is not happening on stock components at 8k rpm, at least never that has been seen... Hope this helps.

 

I love learning.

 

Hey, glad I can help. I'm no expert, but I researched this before taking the 8k rpm plunge myself. I am very happy with the results!

 

Is it worth revving the Cooper past 6750? Doesnt power fade toward the upper RPMs?

 

I don't think it's worth it for the Cooper, but I'm rusty on Cooper power curves. If the engine is still gaining power at the redline, then yes. If it's flat or sloping down, no.

 

Sorry guys...but MTH will not, under any circumstances, go over the 7250rpm limiter. Even if you have stronger special bottom end bolts etc etc.

MCSWRKS- One of my customers Cooper revs upto 7200....all the way infact and the power is awesome

 

They sure wont, and actually its a smart move on their part. The valves start to float on a stock head with stock valve springs not too far past that rpm. For liability concerns and since they cant verify that the user has the needed parts upgraded before raising the limiter that high who knows how many cars will be dammaging engine components by reving the stock parts that high. The bottom end can handle it at least from what we have seen but there is something left to be desired in the stock valve train for those rpm's.

 

It said in the other forum that the stock engine, stock valves started floating at 8200 RPM, but for reliability sake cut off would be 8150.

https://www.northamericanmotoring.com...ad.php?t=55748

 

Well, I am not going to argue the position but I will tell you that the stock valves/springs and cam float before 8000.

Just trying to give a heads up in case somene was considering running their STOCK valvetrain up that high. I will be running my car at those rpms soon as well but not with STOCk valvetrain.

Best I can tell you is do your homework, dont take it all on what is said here or at least really consider the source of the information!

 

Dont worry, I have a neutral position here. I was thinking last night "gees, oem engineer has really gone far..." I dont know if it can really rev that high or not, but I really never plan to take it past 6750 ever. There isnt any more power in the n/a cooper anyway.

 

[SIZE=2]So you are willing to take the risk of blowing up your engine by having a 50 RPM cushion? What happens if they are wrong and the valves float at say 7800 RPM? Are you willing to rebuild your entire engine?
[/SIZE]

 

well said

 

Detlman, I completely and respectfully disagree. It's been done safely and can be done safely, from my experience. It seems like, no offense, FTR is marketing their head as the only safe way to do so. Meanwhile, not once has the "proof" of valve float been provided. What methods did you use to identify the float? As far as I have encountered in my research before going 8000+ myself, uprated springs are not necessary, only added protection. I have Cosworth up-rated valve springs, as you know, and I personally recommend being safe if you so desire, but people do not need to buy your head to get uprated valve springs! They can get Ferrea double valve springs custom made for far cheaper, with at least as much, maybe more, confidence in the preparation of their motors. Of course, neither I nor the developers of my software [which is now marketed by M7] have ever seen any evidence _whatsoever_ of valve float, in more than a year of using that software and thousands of miles of track proving it, all without a single failure or sign of fatigue.

Here is the thing, from my own due diligence: to identify valve float you can either look closely at repeated dyno runs and see if the valves are floating, because you will lose all sorts of power and AF ratios will go crazy, you can inspect your springs for failure/fatigue- again, empirical, or you can literally observe the valves at their high rate of speed. The last, while of course the best, is impossible to do without very complicated equipment. In inquiring originally about my tune, it was relayed that the developer was quite skeptical and expected to blow an engine like that, but decided to try it on his own track machine. Yet, to his surprise, doing numerous dynos to investigate the high-rpm integrity of the valve train AND taking his engine apart repeatedly, carefully and testing spring performance, he saw no ill effects. Miles later, same story. SO, yes, it's great to be skeptical, but what PROOF do you have that the valves are floating? Otherwise, you're just speaking on opinion, and just like you I was skeptical- now, I am not.

One more thing: if you are seeing valve spring fatigue on twin charged rigs at high rpm, which is entirely likely given the extra stresses imposed, this does not, as far as I can tell, at all apply to the setting of our SC'ed cars.

PS: It is almost silly, in hindsight, to worry about the fatigue in a street car especially, if you think about how often and for how long any of us remain in that portion of the powerband. The stresses are just not there, considering that there has been no failure whatsoever in engines which are held in that region for minutes at a time.

Sorry for the long response, but I wanted to be complete in my posting. Thanks for reading!

 

Its your right to disagree, but you are the only one who mentioned FTR's head not me.

Like I said I am not here to argue the point only pass on info that I KNOW to be true. Therehas been a ton of testing that is not free, what is free is that Iam letting th emini comunity know they need to do due dilligence in deciding what they want to do with their cars and how hord they want to push them.

I am not going to say how I know or determined valve float and it doesnt really matter but I will tell you weather you want to believe it or not they float sooner than 8000.

Ingsoc, it seems you have an agenda to discredit FTR for whatever reason, we have never done anything to you to deserve you to go out of your way to post negativly towards us the way you do.

And just for the record I have never even mentioned our head here or offered it for sale to anyone, just stated the facts of the STOCK valvetrain components.

Again, I say use due dillegence when deciding what parts to use, how hard to push and the souce of the information.

 

I have absolutely nothing against FTR. I have personally relayed my happiness and congratulations to Tim via pm more than once on your great racing success. He has written me back, and we've had quite some fun shooting the crap. Tim is an awfully great guy, a really kind and funny individual. I encourage everyone to chat with him if you get the chance.

That said, you [not Tim] have made claims but provided no proof. I have experience. I guess it's your word versus mine, and it really saddens me to think so, because I have nothing against you as a person. I just urge you to consider how little people have to go on in believing you in the long run. I am going to be posting dyno runs for everyone to see of my car successfully teasing 8000 rpm when school finally lets out and I get to go home. I don't own any other cars with the software, so I guess we'll have to wait for a person with the stock valve springs to post, too. Fair enough.

If you truly believe that you know something important that we [people, I am in no way affiliated with my developer friend or M7!] don't know, you should probably share that information, for the good of the community. I would. My $0.02.

 

Consumer diligence is definitely in order on this matter. All we have so far is claims from a poster with some gaping credibility gaps (anyone rememeber the intercoolers operating by evaporation? ) claiming that there is no valve float above 8k.

I asked for any evidence at all of this being a reality (dyno plot, the person who did the software development coming on here, data logs, etc) but ingsoc has refused to provide it. He is claiming that it is fine to go 8k+ with the stock valvetrain based on his expertise with an unnamed person who has developed unnamed software, has invisible dyno charts, and who is too busy spending time driving around his family at 8,000 rpm to help back up what ingsoc is claiming.

Caveat emptor.

 

Sounds like a winning plan. I dont expect everyone to simply belive be just because, but I think I have always shown good character and integrity and that should say alot. I would loove to tell you how we know the stock valves float but you know what would have to happen then.... ROFLMAO

Lets just leave it at that since we arent going to completly agree on the issue.

Have a great day Ingsoc.

 

Having recently experienced the effects of valve float on a personal level (try shifting into 2nd at 108 MPH sometime ), I'd suggest that as european manufacturers refuse to make engines in which valves can't actually physically contact the pistons, I caution those of you on limited budgets to tred carefully into these waters. The stock Porsche engine I lunched also has a stock 7200 RPM redline. While my excursion into upper stratosphere of RPM was above 8250 (the data logger stop reading above that...I'd guess I might have touched 9 grand) consider this a cautionary tale that is somewhat applicable here.

Engine components get tired over time, valves, springs, cam lobes are not truly perfect or matched, heads aren't torqued perfectly, bits stretch etc. Should Mr. Piston get into a little altercation with Mr Valve at 8 grandor so... well, lots of expensive stuff. And I clutched and shut the motor down immediately. According to the logger, I was above 8000 for less than 1/4 of a second. To my mind it seems silly to up the rev limit to thes levels without going to titanium springs, better studs etc and other forms of racing hardware exotica, not to mention adding all the stuff to take advantage of revs in that range. In PCA, we call motors designed and built to run up in these ranges, 'hand grenades' for obvious reasons and these suckers cost as much to build as a brand new MC. Add a turbo and its not impossible to spend in excess of a well equipped JCW. They go a season or three or about 100-200 hours of running time before they are torn down and renewed. And these are normally aspirated motors that are putting out around 110 HP per liter. With turbos, you mileage may vary. Ask me how I know. I'm right now in the process of building a new motor to replace the one I blew and I'm having to make all these decisions on how to build it as we speak, how competitive do I want to be versus how often I'm going to have to rebuild it.

As the joke goes, Customer: How much power can I get out of this motor?" Mechanic, "How much money you got?" Sure, maybe with a MINI you can 'safely' run a stock motor at these levels for some period of time, but for how long?!? And at what boost pressure? I'm not even an owner yet, let alone an expert, but I'm pretty skeptical that running these engine over 8 Gs either repeatedly and especially for any extended period of time has no effect on your motors longevity.

 

You sure are a golden hen, Andy. People make mistakes. I have made mistakes. Lots of them, in life and on here. That says nothing of the value of my character in relating personal experience. If anything, my admission should at least show some humanity and good will in my enduring you. Why would anyone else do that? I'll humor you long enough to get dyno plots up- I've said that before. I will relish in your humble. Then, you'll have to go find another person upon whom you can levy needless insults and publically scorn without merit, to even more fully establish your character or lack thereof. Maybe one day you'll live to feel good enough about yourself that you do not have to prove anything. Until then, NAM sure is lucky to have you, oh blackest of sheep. Peace.

 

eek is right
how did u manage to pull this one?
anythin' happen to the tranny?

 

I'm thinking about this, and 108 mph in second gear in a Porsche is a lot higher than 9k rpm! I wish I had my father's 911 here, but I'm pretty sure that the car can't get above 65 at 7200 rpm in 2nd [I've driven it, trying to think....]- hell my MINIs gears are super tall, and I would only be at about 70 at 7200 rpm. So, assuming the 911 goes 65 at 7200 rpm, to go 108 mph, I'd imagine that you were going about 70% faster than redline [65*1.70~=107]. That's 7200 * 1.7, or 12100 rpm!!!! EEEEK! I can't imagine! No offense, but that's more than 50% higher revs than an engine at 8k. Food for thought.

 

I've managed to do this too a couple weeks ago. I was on the highway coming home from Flordia when someone went screaming past me. I was cruising around 90 in 6th then droped it into 5th up to 100 - 105 and then went for 4th. In my fury of madness for grabbing gears I hit 2nd by accident. I realized this was a mistake as soon as I let the clutch out.

Myself personally I wouldn't rev a high RPM w/o head work. Even if the truth be known that stock heads are fine, I like to have that little warm and fuzzy inside.

That being said, MTH your NOT going to write us a program for high RPM? It seems that there are people out there requesting it. Thanks!! -- Johan