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Not too many free roads here over at Bangladesh . My car is a daily and I drive it to work like a turtle everyday. Logging and WOT's are all done after midnight
Update on the tune:
Car is consistently making 500WHP now. I'm wondering if adding 1 degree more past 7000 will make any difference. What do you guys think?
VD and log snapshot below:
Since your MIVEC was not fully operational while swapping cams,
Have you had any reliably confident data while MIVEC working as it should, that you could overlap TOMEI vs S2 VS HKS..?
I've used S2 and HKS, and found HKS to idle like stock virtually (274/278), while S2 are a bit wild. On top end using HKS 7460 and BBk-3B (Equivalent to XTR 2.0 I believe) top end was about same S2 to HKS 274/278, surprisingly (E85 29psi peek).
Tomei, I have an impression they may not be as "sporty". Nothing wrong, just midler.
My findings are similar to yours whereas HKS 274/278 & GSC S2 results were similar in terms of power. Tomei makes more power at the top. Surprisingly, it doesn't sacrifice anything in the mid-band despite having the highest lift (11.5mm) & lowest duration (270).
I don't have back to back comparison on the same day, but have data few months apart.Boost is about 0.5 psi apart for the 3 runs, AFR similar. Timing is different for Tomei as I'm running lower timing down low to promote quick spool.
Vacuum for HKS is absolutely stunning. Stock if not better. Tomei is also very good. In fact with Mivec, i'd say 90% close to stock if tuned properly. GSC idle is totally wild compared to these 2 cams.
HKS: 18-19 inhg
Tomei: 16-17 inhg
GSC: 13-14 inhg
Please note, my car has a 2.4L stroker motor. For stock motors, it might be different for these cams.
Apart from numbers, In terms of snapiness, the HKS shines. Car pulls like a rocket as soon as i press the gas. Tomei feels less snappy below 3000. GSC is in between.
However, if going WOT from 1st gear around 2500RPM, nothing comes close to Tomei.....car pulls like a freight train. About 70mph in 5.6sec. Each gear shift requires less than 2 sec.
Please excuse my grandpa shifting....I'm more of a mechanic than race driver Tomei procam 270 1st - 3rd gear pull
Thank you for truly remarkable display of thorough data and personal observation.
I really appreciate it. Somehow the reality is different than perception. I also run strokers, 100mm, 2.3, so results should mirror yours.
I am a bit puzzled, surprised, by the clear and distinct advantage of the Tomei 270 pro Cams, over both HKS and S2.
I can buy the notion, the idea, that S2 and HKS perform similarly, with slight low end advantage given to HKS and superior idle, while the very top end maybe to S2, but only after 7000rpm.
In contrast, TOMEI just trounced them all over.
Is there any possibility your MIVEC issue or conditions, or anything else influenced the situation? You were tuning the car, started from mid 400 and eventually got to 500+.
It was a process.
Since I run stroker, I am very interetsed in the Tomei results.
Nice build. I really enjoyed the torque with my 2.4L in my IX RS. Was running Cossie 272 cams. Ended up running the exhaust
cam -4 degrees. Turbo was an older FP green which at the time was a bit better than a stock IX turbo. Looks like the Tomei cams are working really well for you. Thanks for the comparisons.
So 80 degrees there in winter??? BBrrr...Break out the jackets !!!
@alpinaturbo: I'm a bit puzzled myself on reaching 500 withe the Tomei's. To be fair to HKS & GSC, two conditions are different:
- Weather is cooler outside by around 20-25 degrees. Maybe VD compensation is not enough to offset the actual ambient temps?
- I replaced the left balance shaft bearing (my balance shaft is deleted) as it was leaking oil and making oil pressure low globally. Not sure the slightly lower oil pressure would impact MIVEC as i'm not logging it since the problem was fixed. .
@whtrice: I also ran my exhaust cams to -3.5 degrees when I had 4G63 belts on the 4G64 block. Now i'm running +1 degrees with 4G64 belt and ER over-sized oil pump gear. Note: I have AEM adjustable timing gear on the exhaust side and ER modded MIVEC gear for around 33 degrees max MIVEC. Exhaust gear lines up perfectly while intake is about 1 degrees off.
Winter has just started here. Around Christmas time, temps should go below 50. Looking forward to logging then for some added ponies
I am also surprised by the spool: 4.5psi by 2500rpm, 12.50psi by 3000rpm, than a "slow" progress to 20psi at 3400rpm and full boost about 3800rpm.
I would expect that once past 12psi by 3000rpm, the 2.4 would spool up XTR 2.0 to any boost before 3500rpm, maybe by 3300-3400. Are you purposely slowly feeding in boost?
Regarding your oil-leak past balance shaft, I think MIVEC would get zeroed at worst, so once in midrange the cams would be all same to the redline.
@alpinaturbo: I'm also working on advancing the spool for last few days. The post from Mrfred on his BBK 3B dyno results shows impressive spool from his 2.0L which i'm yet to match with my 2.4L . I was at 97% WG duty cycle at 3500 RPM. Will try 100% and see what difference it makes. Also, i'm using 16psi spring on my Turbosmart WG actuator. Maybe going to 18psi might do the trick.
@GTA.RS:Had a lot of fun testing the cams over the past 6 months. Happy to share the results with the mass
You can see how S2 balance out low-mid to top end, most of us sign of by 7000-7500, because few turbos can fill our motors above that RPM, and few cams make power up above 7500rpm, and than there is the drivability of S2 vs S3 and Tomei 290 etc.
We spend most of our time moving along at 2000-5000, not 7000-8500.
Tomei 270 Procams seem to really take a life on their own when applied to stroker.
As I re-read the post, I realized you had upgraded from MAF to SD, while on TOMEI.
If you take the MAF to SD into account, it seems to me that TOMEI and HKS virtually overlap while on MAF? And S2 lag a bit but overtake on top.
Am I seeing this correctly?
All graphs shared for the 3 cams are from SD tune. I installed MAF only for a week few days ago to check how difficult it is to tune.
The Dsport shootout was done on Evo 8 I believe while on MAF. In my experience, SD with no restriction before the turbo makes a Huge difference. Checkout my WG duty cycle graph below for MAF vs SD to attain similar boost curve without changing anything else.
I Actually thought my Turbo is shot ....thank god for SD & Tomei larger intake pipe
Nov 15, 2020, 12:31 AM
. My car is a daily and I drive it to work like a turtle everyday. Logging and WOT's are all done after midnight 
. I was at 97% WG duty cycle at 3500 RPM. Will try 100% and see what difference it makes. Also, i'm using 16psi spring on my Turbosmart WG actuator. Maybe going to 18psi might do the trick. 
