Requesting your expertise on making NA power on big cams with the H22A.
Posted: Tue May 04, 2021 2:42 pm
Brief backstory.
My H22A (JDM blacktop) was last tuned for stock cams with most current boltons using a P72 ECU with Neptune. I also have a FPR, SAFCII and AEM Wideband for minor adjustments. Peak dyno numbers were 194whp/143wkw. Best ¼ mile time was 14.4@158km/h (~98mph). I later switched to Euro R cams (Example of ¼ mile run with EuroRs with 2.5" exhaust: https://www.youtube.com/watch?v=wjGugEm75X8&t=16s - this video link seems a bit off, Youtube error. I have others uploaded if this fails) and had the exhaust enlarged with the help of a Lude brother from 2.5” to 3” (Hytech replica header collector modified from 2.25” to 2.5” expanding to 3”). Now to add to those, I have upgraded the valve train and camshafts yet again.
I took a maintenance opportunity (replacing leaking valve stem seals) to upgrade the top end (if interested I made a video clip of the process: https://www.youtube.com/watch?v=vbK7ijbRnf0 - severely truncated - it took a while to get the job done). The valve train now consists of: Stock valves (the head remained on block so still “unopened”), Ferrea valvetrain (80LBS dual spring) and Jun’s Stage III camshaft + Skunk 2 Pro cam gears (Both zeroed on adjustment), all on a stock H22A 10.6:1 bottom end. I did the mods myself, so no machine shop involved. The engine has not been degreed but nor has the block been torn open. I have done a solid run-in (~500kms of < 3.5k rpm) to seat everything. I did a few pulls to get the wideband readouts safe (~13-13.5:1 at WOT) and did a few runs down the 1/4mile.
The punchline.
The best ¼ mile time on the Juns was 15.29 @ 93mph. To put that in perspective, this car in 100% stock trim ran the 1/4mile in 15.2 @ 93mph with 157whp (all on the same dyno). I knew stock compression was not ideal, but I was not expecting a loss in power with more lift and duration, even untuned and un-degreed (that makes it ~40-50whp loss!).
I am trying to figure out where to go from here. Degree motor? Compression test? Revert to Euro R camshafts and wait for high compression piston upgrade to happen, or get a full dyno-tune and see what it makes. Any input appreciated. Car runs "fine". Idles ok once its been running for a bit. Drag video link here: https://www.youtube.com/watch?v=hbH1dWVpi0I .
My H22A (JDM blacktop) was last tuned for stock cams with most current boltons using a P72 ECU with Neptune. I also have a FPR, SAFCII and AEM Wideband for minor adjustments. Peak dyno numbers were 194whp/143wkw. Best ¼ mile time was 14.4@158km/h (~98mph). I later switched to Euro R cams (Example of ¼ mile run with EuroRs with 2.5" exhaust: https://www.youtube.com/watch?v=wjGugEm75X8&t=16s - this video link seems a bit off, Youtube error. I have others uploaded if this fails) and had the exhaust enlarged with the help of a Lude brother from 2.5” to 3” (Hytech replica header collector modified from 2.25” to 2.5” expanding to 3”). Now to add to those, I have upgraded the valve train and camshafts yet again.
I took a maintenance opportunity (replacing leaking valve stem seals) to upgrade the top end (if interested I made a video clip of the process: https://www.youtube.com/watch?v=vbK7ijbRnf0 - severely truncated - it took a while to get the job done). The valve train now consists of: Stock valves (the head remained on block so still “unopened”), Ferrea valvetrain (80LBS dual spring) and Jun’s Stage III camshaft + Skunk 2 Pro cam gears (Both zeroed on adjustment), all on a stock H22A 10.6:1 bottom end. I did the mods myself, so no machine shop involved. The engine has not been degreed but nor has the block been torn open. I have done a solid run-in (~500kms of < 3.5k rpm) to seat everything. I did a few pulls to get the wideband readouts safe (~13-13.5:1 at WOT) and did a few runs down the 1/4mile.
The punchline.
The best ¼ mile time on the Juns was 15.29 @ 93mph. To put that in perspective, this car in 100% stock trim ran the 1/4mile in 15.2 @ 93mph with 157whp (all on the same dyno). I knew stock compression was not ideal, but I was not expecting a loss in power with more lift and duration, even untuned and un-degreed (that makes it ~40-50whp loss!).
I am trying to figure out where to go from here. Degree motor? Compression test? Revert to Euro R camshafts and wait for high compression piston upgrade to happen, or get a full dyno-tune and see what it makes. Any input appreciated. Car runs "fine". Idles ok once its been running for a bit. Drag video link here: https://www.youtube.com/watch?v=hbH1dWVpi0I .