On the graphs from my M2's which are similar specs, I only lost power below 3000 rpm and it was barely measureable 5 MAYBE 10 hp which your really never at even when cruising. Driving I don't think I really even noticed the difference.

Here's the link:
http://powerpages.tumblr.com/post/43...sworth-m2-cams

Here's my chart before and after:

 

this is stock cams vs. the m2's?


i have the kelford 272's and they work really well. however i did lose A LOT of vacuum which can lead to an unstable idle, but with your mivec that should not be a problem

 

^^^ No. TB shaft seals were found to be leaking so those were changed out with the cams. So the mid and upper range is more dramatic. They were meant to show the difference in low end loss.

 

ah i see, i guess i should have just clicked on the link

 

A recent car I tuned with an FP Green gained no power moving from stock IX cams to Cossie M2. It was retuned to suit the new cams which gave no more ignition timing, and it didn't drive any nicer. It lost refinement low down. I played with a variety of MIVEC maps. The exhaust cam was swung between -4 and +4 on the dyno in five steps, and the plots hardly moved. The belts were rechecked, wideband AFRs checked on different meters. With either set of cams the engine is competitive with others of similar or higher spec. When we moved to the red it had the Cossie M2 on all the time, so I can't comment on a Red sized turbo on stock cams (I would have tried it on my engine if the Red didn't surge so bad below 4000 RPM in high gears).

Just a different opinion of an unbiased test where the results didn't show the before-after that is so commonly seen on bulletin boards, where people tend to select the pair of graphs to suit their conclusions, we all like to find patterns and explanations, even if we have no vested interest in the results. In this case perhaps I'm over-extrapolating discouraging results and being negative about cams generally at this level on an Evo.

 

thats interesting.

one of the guys here was getting about 245 kw's with a 20G (IX, 98RON), put HKS272(clone I think) in and retuned and hit 265 kw's. He had to change the MIVEC as well.

I guess that confirms what I should do, turbo first then *maybe* cams...

Thanks John!

 

At this level, by far your biggest restriction in the whole system is a small turbine wheel blocking off your exhaust, proven from the fact that you can add nearly 200 BHP over the stock turbo by fitting a GT35 with stock cams, but with street sensible cams can only add little more than the confidence interval over the stock cams on a near stock turbo. With cams you'll move your power band around, but with extra boost at lower engine speed you'll probably make similar power on the stock cams, especially if you have sufficient octane. If you have stock rods, do you really want to move the power band nearer to 8000 RPM anyway? Even if the loss is small low down on a graph, the transient response changes could be altered more than many let on.

On previous cars I've wasted a lot of money on small incremental upgrades that you can get excited about for a week, but make a very small difference when away from the graphs. Changing from stock cams and turbo does change the nature of the car making it less throttle adjustable and more point and squirt, which I don't necessarily prefer.

Personally, I think go big turbo and stroker, or go home I would no longer bother with a series of small changes that don't overall improve the car. There are many biased salesmen that will sell you stuff that either plain doesn't work, or at best is marginal with an understated downside to driveability, refinement, reliability and whether you can get out the car easily and without a big loss once you want to get rid of it.

I also believe that the US Evo 8 has cams like the Euro Evo 8 260, which are very mild. Because this was the first Evo in the US, there has been a large community of people who have great gains from cams on their 8. I'm still not convinced on the 9 for a flexible road car. Even on the stock turbo, on the twisty roads I like, I lose far more time through lag and boost threshold than I do through a lack of top end power. The gaps between the lower gears are considerable!

I think in the UK and Aus you also tend to get put in prison for driving at the speeds on the road where the big turbos and cams really come into their own. Pursuing power for dyno results or quarter mile, or even circuit use is of course a different matter, but I maintain that less is often more.

 

I agree with changing cams on a 8 you certainly make more power and torque. The S1 do work on the 8 very well. I don't rate them on the 9 though.

I will be going with kelford 272 soon but the turbo will be a 35r.

Follow David Buschur's performance upgrade on his website.

Also cams do reduce surge too.

 

The Green surged a bit with the stock IX and the M2 cams though, no obvious difference. The Red surges horribly on the M2.

 

Seems to me the Cosworths arent as much as they are cracked up to be n smaller turbos (not that I havent got some gain out of them). I have a definite increase with the GSCs in my car, the other cars we have done, and the Kelfords we have done. They arent listed now, but the Kelford B cams which I believe is what the A cams are now are burning a hole on my shelf

 

Kelford 9-177B are discontinued however are not the same as the A's. They are actually a set that we think would be a killer on the stock turbo. We have a set here we are trying on a 430whp+ car to see if we make any gains.

 

A cams- 217/214 @ 1mm lift, and 11.00mm/10.35mm

B cams- 216/222 @ 1mm lift, and 11.25mm/10.50mm

Scott,

Thanks for the clarification I remembered they were close but I didnt remember how close. I do like the higher lift on the B cams and the slightly more aggressive exhaust profile. They have a wider centerline as well on the B cams. I think these would be great for a stock turbo car looking for a really broad powerband and not so much peak power.

I did want to clarify what I said about the Cosworths as well. They make GREAT power but do seem to sacrifice some low end and do not idle as well as a comparable Kelford or GSC.

 

$$$ to HP gained better off invested in turbo IMO this is what I was eluding to in my previous post. This is why I'm waiting and prolly will not do cams. Hopefull that sometime next month I'l lget the Red as I sent a core in for upgrade. I knew it would take them a long time so I bought a used 9 turbo and sent it in so I could still DD my ride. I'm at around 365 on stock 9/E85 and my goal is anything over 400 which should be easy on red with stock cams. I been waiting around 4 weeks so far.

Is even the 20kw listed above worth the cost of cams and labor for those that don't want to risk install themselves (namely me)? to some yes but to to others.....

I guess if the turbo causes surging and cams ARE the cure then one mod will drive the need but we shall see

Hell I will leave a lot of power on the table but I'm considering using stock o2 and unported stock manifold and stock TB along with intake mani. just to see what it will do.

I had planned the ported goods but ran across some used Ohlins that I could not resist not to mention I might need a clutch with the added power. If its not one thing its' another

 

I changed one mod at a time, glad I did it this way to prove to myself that the next step was needed. In the end changing cams certainly helped surge, but overall the drive was more pleasant, area under the curve.

Looking back if I followed Bushur Racing mod stages that would have saved me alot of time tuning in the long run.

 

The 8-177-B cam looks interesting.

JohnBradley: Would the extra lift of the B cam be worthwhile on an unported head?