Anyone out there running GSC R2s on a 2.0L motor Evo 9? If yes, I'd appreciate hearing about drivability, e.g., idle, off boost responsiveness, and I'd like to hear about how much they shifted the spool threshold. I'm only interested in Evo 9 experiences because MIVEC gives a significant advantage for taming drivability.

 

I think Tom, TSComptuned has a few 2.0s with them running around.

 

He has, vd results included..granted mrfred is looking more for things not shown on a graph.

 

I tuned one. https://www.evolutionm.net/forums/ev...ireescape.html

PM him. I'm sure Andrew would be happy to help you out.

 

Idle quality is slightly worse than the S2s and R2s idles @ 11 in-hg on my setup. Driveability is no different than what I remember from the S2s
S2s - 30.1psi @ 5107rpm (3rd gear dyno)
R2s - 30.1psi @ 5303rpm (3rd gear dyno)
I will dyno the setup on a dynojet so I have a good apples to apples comparison vs the S2s, but there is a slight loss of spool with the R2s.

I did not have the turbo speed sensor hooked up when I ran the S2s, but with the R2s the GTX3576r is not keeping up with the engine and the turbo is riding the choke line. The R2s are likely not the optimal cam on my setup (too much cam) with a 64lb/min turbo, but will hopefully shine when I install the GTX3582r (75lb/min).

 

Thanks for the info about drivability. Nice to hear that there is only a very small change in spool threshold. Interesting to comment about the R2s being too much cam for that turbo. Seems that the better the flow, the better the VE and the easier it is for the turbo to make max power.

 

Closely bordered by the tendency to over work the turbo??

Mrfred you monitor the back pressure so that's an excellent bit of data to compare if you do switch.

 

Hey
I think I was one of the first to post up some results from the R2 cams on a Evo 9. I've had them in for maybe 6 months now. At first I had a few issues, mainly with very low speed driving (car parks speeds) and with knock up high in the rev range (above 6K and after lift on wot runs).

At low speed I was having problems with the car "kangarooing" (don't know if that's an Aussie term), surging on very light throttle. The knock was showing up when I was tuning with my previous tuner, it seem to be starting at 6500ish revs and going on past lift at 7500is. My tuner never seemed to be able to get on top of it, but it seemed to be there most, but not all, of the time, regardless of timing or fuel. I had my suspicions that it was cam related but was unable to get any solutions from my tuner at the time.

I decided to contact Chris at Pure Drive maybe early September and explained the issues i was having. Spoke to him about the knock and surging and got to tuning the following week. First tune removed the surging at low speed, their was a big issue with injector scaling found and with this sorted driveability is great. Lots of people say "better than stock", my car is! much better.

Chris worked on the idle tune for maybe 8 maps (can't really recall) but had the idle A/F pretty much sorted. We started Wot tuning and the knock was showing up. Chris thought maybe the cams had a part to play in this. He spent a lot of time fiddling with the Mivec maps, changes to that map made a pretty big difference to the high rpm knock after maybe 15 or so maps I can say that there's basically no knock now. I feel with these bigger cams, on Mivec engines, that their is an ability to tune knock with the Mivec setting, Chris seems to have sorted this well.

Car is making close to 500hp (on VD) on 93 fuel (sig shows mods). No knock, really drives better than stock, and I can crawl around at a few miles per hour in the local shopping center car park without a problem. I guess to conclude the cams work great on a Evo 9, but the tune plays a big part in how well. Cheers

 

I'm hitting 30 psi on a HTA 71 at 3800+ RPM. Like the poster above said, MIVEC plays a big role. One thing I noticed right away is the timing advance has to be on the conservative side due to the onset of knock at high RPM (93 oct). Basically I run 1 degree at peak torque and slow ramp up to 9 degrees at 7500. The knock is not bad, between 1 and 3 counts but they are persistent which will dial back the advance timing anyways.

The graph it's from a couple months ago, since then I have refined the MIVEC map for spool up and leaned it out quite a bit as well. Like I said, 30 PSI by 3800+ RPM and quick response for DD...too quick sometimes

Just for reference, I have a MAP O2 DP open, 3.5 IC, COP and a ported hot side as well. On SD version 1.

 

Thanks for the info. If you haven't already done it, try rapidly tapering MIVEC to -1.2 deg by 5500 rpm. That might help with your high rpm knock issue. What cams did you have installed before?

 

Thanks, will look into that. I currently have it zero out by 6000 and -0.6 at 7000 rpm; so less advance it's the answer. Interesting

I had the stock cams before and to be honest the car feels the same and as responsive as ever.

 

Thanks much on drivability. If you're at 0 deg MIVEC by 6000, you'll probably not see any improvement by going to -1.2 deg by 5500 rpm.

 

In the 4 years we have been developing the cams I havent ever seen them be less drivable than the S2...I have always felt that they were better idling and driving even on a 2.0L. In Andrew's car (the first Auto Evo) they picked up everywhere and drove better. With the final drive change in his car he even managed 30 on the highway with an FP Red.

 

pretty impressive cam

 

I don't notice any drivability issues and running 38deg under cruise I get ~27mpg with R2s and 5speed.