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Discussion Starter #1 (Edited)
RjR cams: 590 intake & the RjR61+3(6) exhaust.



In comparison with the Stella's fast road:



C&B road max, original air intake (no GG cold air intake yet) and dyno test started accelerating from 3000 rpm (1500 in the latest ones):
 

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Wow. Been waiting for this for a while now.

according to this site: Online Unit Converters ? Mechanics ? Torque ? Compact Calculator
28.4 kg/m = 205.42 lb/ft torque
203.6 Cv is approximately 200HP

I see that Dissipata is set to "-" on the Dyno so if one used say 15% Dissipata (driveline losses) you'd be at 230 flywheel HP at indicated 6600rpm.

Rough Engine Horsepower Determination Program
I used mean compression of 10.5 which is probably where you're at.

Said it all before. I appreciate the comparo, which illustrates that some improvements can be made, with the understanding that these aren't "jack-n-the-beanstalk" cams, for a street car you've extracted about all there is. Costs go up exponentially for each little bit. Next would be 3500-4000 for proper port-n-polish (dollars).

This is why manufacturers increase displacement first. Almost no one is using only two valves anymore - for obvious reasons. So, what's next Alfatakesitall?
 

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Hi Alfatakesitall:
Nice curves there! Very close to each other relatively.

Got a bit more than any of your measuremets with C&B fast road cams, so its surprising that not any of your cams did give more! Our engine was measured in engine dyno before install. Some years ago.

GK.
 

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For comparison, this is a bog standard 1989 3.0 running ljettronic



Much lower results, but as this is comparing, it maybe useful to have a standard car here.
 

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Discussion Starter #6
Thank you all... My CR is 10,5:1!
I was wondering to increase up to 3.700 engine, still using 12 valves.
Any idea of the data (dimensions) of 3 litres 2 valves x cylinder engines' OEM valves?
 

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Original valve sizes being 44mm/38,7mm on the 3L 12 engine, Jim K. had a couple projects increasing the inlet to 46 mm with inlet porting at the same time.

In the face of a lot of work involved in a bore increasing project, although fun, and getting a few extra horses, why not consider a turbocharger/supercharger solution and get some real extra power?

GK.
 

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I'm a bit doubtful that the RJR cams max out at 60XX rpm. It should make power all the way till almost 7000 rpm.

Do you have elongated bolt holes on the cam pulleys? That allows a little bit of adjustment, which is all you need. I'm talking about the 3 small holes for bolts that go through the pulley.

Are the RJR cams as noisy or less compared to the Stella cams?
 

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Discussion Starter #9
RJR cams are no doubt much less noisy than Stella ones (probably just for the lower valve lashes... anyway no problem with the values Richard suggested).
That posted is the best result got with those cams.
Of course we did what you said: only a very slight improve (that is what you see in the graph).
I am selling them very soon, if anybody is interested in buying them he can contact me via PM.
 

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I think there has been too much hype around those cams! When eventually seen the results they came out with the lowest results!
Obviously there are cams which are better choices if you are going for power!


GK.
 

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Richard Jemison
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Cams

Stefano`s cams were not by any streach cams made for "Power" as his instructions for the cams were for street use, and repeatedly stressed to not have valve train noise.(Ticking). He wanted similar power to the Stella`s he was running, but had no useful data for those cams as you can see below. That is typical for the european cam builders as said many times.

Since the valve noise was his only concern I even suggested to him before ordering cams that he close the lash on what he had.

His cam timing with the RJR cams should be changed to enhanse top end if that is his wish (retard cams 2 degrees at cam, (4 deg at crank))

Simple "tuning that most do on the dyno.

Hi Richard,
the only data I have on my actual cams are as follows:

Cam Lift Inn/Cam Lift EX-Duration-Lobe Center Angle-Valve Lift TDC

10,9/7,3 - 270°/270° - 102° - 2,3/1,9


As I told you I cannot give you all the data you need but consider that some metal removal has been already done when I run with racing profile (C&B corsa).
So no probelm for that and anyway I do not want racing profile anymore.
I want to run fast soon, not only after 3500, push hard up to rev limiter without having annoying ticking.

My engine has 10,3:1 CR, full CSC manifold exhaust system, 164 QV plenum and ported runners, competion ECU without MAF from EFI Technology, fuel pressure regulator increased, fuel pump increased, increased injectors, engine lightened flywheel, lightened connecting rods, K&N cold air intake, increased aluminium radiator, Denso Iridium sparks and so on.
Now at the end, after a lot of regulations and I don't remember anymore how many tests, it is driveable as a stock 75 and runs very fast.

Which cams can you sell to me and, of course, at what price.
When you consider the "pulls" started at different RPMs you might change your evaluations, and from the similarity of the curves there is a problem with either fuel ratios or timing and likeky both!

As 75EVO has said even the even milder RJR cams he is using (the 570/744 made far better power than the same C&B cams as shown.
 

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Why I'm a little bit suspicious is how come this cam with almost 11mm of lift can't make more power as the QV cams. Not in terms of absolute power, but in terms of revs vs power. I'm not saying Alfatakesitall's mechanic is bad, but something is amiss. We should see power all the way to at least 6500 rpm. Anyway this is just my thoughts. When I had my car on the dyno with similar cams it made power all the way to 6800 rpm. But then again I had the short GTV6 runners.

Actually a while back when Squadra did a special 155 V6 project with Spider V6 cams it also made power past 6500 rpm. So something doesn't quite make sense to me.

BTW I'm not saying RJR cams are the best. If someone can show other cams which can perform the same or better and tick less, then those cams would be better than RJR cams. RJR cams are good enough for me.
 

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I think with these results (200-211Hp) and smoothness being a priority, little noise etc, the SZ cams, which I initially suggested, would have shown well off here! They are smooth in power delivery and very quiet. Power under these conditions should be around 210HP.
But cannot see them tested here! Could have been interesting to se that curve on same engine also!

By the way the results which we got with an unported engine was 213Hp/6400rpm and 270Nm/5000rpm. A bit underwhelming for us and others here! We used C&B 292 fast road cams so they got most of the blaim! Also we used bigger than original injectors, so they were not a limiting factor!
Other here reported that they met a limit with original injectors around 203Hp. After changing to bigger injectors the result was 215 Hp with SZ cams. Unfortunately that result was not in our dyno so difficult to compare!

GK.
 

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I think with these results (200-211Hp) and smoothness being a priority, little noise etc, the SZ cams, which I initially suggested, would have shown well off here! They are smooth in power delivery and very quiet. Power under these conditions should be around 210HP.
Firstly Gabork, note that the dyno had "0" compensation for driveline losses and results at the wheels. The SZ motor is quoted by manufacturer at the flywheel dude. this motor is making ~230HP at the flywheel, so the SZ cams would probably not be in contention.

Also note that torque is 80% of max almost immediately which is most excellent for a street motor. 75Evo may have something there and that could probably be contributed to these guys using stock springs or re-used springs that have not been tested as to pressures. When building a motor, utmost care should be given to the valvetrain. If you want to go to 7 or 7500 rpm, you're going to need performance springs with marginally more seat pressure than stock and spring heights have to be dead-on. No mention of AFR's here and that part of tuning can extract a few percent more and with optimized intake closure via-a-vis the static compression - a few percentage more.

Anybody else would be happy with these results. In fact with the previous cams, suggestions were made but without all the pertinent variables nailed-down he's going to come-up short by a bit no matter whose cams he has installed.

20 lb/ft of torque improvement over stock is about as good as it gets on pump gas. HP is derived from RPM so if he had been able to go to 7500 he would have probably attained what he was looking for. The 164 long intake would not be my choice in that instance.
 

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Richard Jemison
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SZ cams

SZ cams are only good for about 5 HP increase in a stock Verde 3.0 engine with stock components ( 9.0 to 1). The Verde camshafts FYI are the same as in any GTV6 2.5 liter.
SZ "S" cams are a big waste of $ and effort. LCs designed for the long runner 164 type intake.

You want higher power at the RPMs these guys seem to be chasing, then the intakes from the GTV6 and Milano/75 are more appropriate.

As to Dyno settings take a good look at temperature and Barrometer settings on the dyno sheets.
Laughable! You can get any result you want with a simple key stroke or two.
You NEVER compare dyno results from different dynos, and look at the setting differences between the two runs on the RjR cams.
Again, Laughable!

But consider the sources of discord. As ususual 101-105 guy and Gabork .... <insulting comment removed by staff>
 

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Alfatakesitall,

Are you selling these new RJR cams or Stella cams? This car looks like a road car, so if you can somehow squeeze 5-7 ore bhp, and the fuel consumption has improved, then you shouldn't sell the RJR cams. The ticking has gone, so that is a big improvement in terms of daily use. That's probably the best you can get from a stock-ish 12V engine without doing up the heads and runner+plenum.
 

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Well, on the charts its written "Potenza motore"=which means "Engine Power" and I dont see any comment that this is not engine power but rear Wheel Power!
What is the value of just showing a couple of charts without any comment of what tune Level of the engine is and what kind of horsepower it is?!

Besides the values did not look so unreal for being Potenza motore as it was stated!


You NEVER compare dyno results from different dynos, .
Maybe thats why I suggested to test the SZ cams in the same set up?

Also maybe the result for cams in our dynos could look different from what is presented here. Interesting to see anyway!

Which reminds me these cams are on sale: Alfatakesitall, how much do you want for them, I could compare them with other cams here, before the engine gets replaced ith 24V. PM etc.

GK.
 

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I'm deciding.
I'll let you know...
OK, let me know. I could be interested in the Stella cams also if you choose to keep the RJ cams on basis of ticking noise. As I will use the cams for racing, noise is not consideration at all! What I am looking for is a cam with a little bit more Power than the SZ cams I have. The SZ cams are very good for revs but lack a bit on lift. A bit of regrind could actually fix that, but as it is I have regrind cams with good potential already! However I would like to test other cams also. There you could come in!

GK.
 
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