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I doubt adding S2 cams will add 30 hp. Maybe your turbo flows a little more than a 71hta? Are you using stock exhaust manifold and intercooler? What are you boosting?
Interesting.
Hold on, you have an Evo 8? The spool looks awesome!
Originally Posted by iD33
Congrats on making the power. Judging by the parts I have a feeling we were tuned by the same person here in SoCal. I made similar numbers on a BBK Lite, GSC S1, 3" RRE Stealth turbo back, Mil-Spec 100 cell cat, AEM intake, AEM 320 fuel pump, and RC1200 injectors.
Last edited by 2006EvoIXer; Dec 5, 2017 at 08:02 AM.
Yep Evo 8, 23 psi on 91 and 27 psi on e85. Stock manifold, stock o2 housing/hot-side, and gsc S1 cams. Fairly certain the BBK lite flows very similarly to the 71hta. Intercooler is from Buschur but I'm not sure if its the street or race core. Ill get back to you on it. Thanks!
You're making much more power on E85 and without Mivec, O2 housing upgrade, and exhaust manifold porting. BBK lite and S1 are the differences that I see. Impressive that these 2 makes more power to more than make up for Mivec, ported exhaust manifold, and O2 housing. Now I'm very curious how much S2 cams will make!
Who tuned your car?
Originally Posted by iD33
Yep Evo 8, 23 psi on 91 and 27 psi on e85. Stock manifold, stock o2 housing/hot-side, and gsc S1 cams. Fairly certain the BBK lite flows very similarly to the 71hta 🤷ðŸ»*♂ï¸. Intercooler is from Buschur but I’m not sure if its the street or race core. Ill get back to you on it. Thanks!
I retorqued my ARP headstuds at 80 ft-lbs again. Only the 3 outter bolts (#8, 9, & 10 in installing order) tightened a bit more. And I have not gone through a heat cycle yet. I can see why people torque these bolts to 85 or 90 ft-lbs on install.
Originally Posted by 2006EvoIXer
I retorqued my ARP head studs at 80 ft-lbs again. Some actually turned a tiny bit! Interesting!
I'll check again tomorrow to see it bolts are fully stretched. I'm actually surprised.
Maybe enough oil was in thread to mess things up a bit?
Quick update. Have an oil leak from light throttle driving. Not sure if it is leaking from valve cover gasket or of it has something to do with the ARP head rod being so tight to screw in that I used rachet to tighten down since it got too tight to screw in by hand (rod closest to driver, which appears to be area where oil is leaking from). I can see injector #4 is wet and it looks like a film of oil on injector and wiring/plug. This is so strange. I'll pull it apart this Friday to inspect. Also noticed that coolant is starting to leaking at a tiny rate. I'm thinking head gasket is leaking, so I'll recheck the ARP nut torque first.
Oil ponding between intake #3 & #4.
Wet injector #4 and wiring/plug. Maybe oil film is from oil vapor?
Need help: I pulled my ARP headstud to measure the shaft diameter and noticed that it is larger than the stock by 1.5mm. Problem is that this shaft is the oil source for the head/valve train. Does anyone know if this reduction of diameter enough to cause problems with restricting too much oil to HLAs?
ARP headstud from kit 207-4203. Abou 11mm.
Stock evo 9 headstud at about 9.5mm. Oil travels up this bolt between head bolt hole and this shaft. My guess is the bolt hole is 12mm. It's a huge reduction of annular space to use thr ARP stud.
Last edited by 2006EvoIXer; Dec 27, 2017 at 10:53 PM.
As for my oil leak, it's from reusing my valve cover gasket. It was cracked at 2 locations that I didn't notice when installing (back at the corner bolt and over a cam).
I finally got a chance to measure each of the GSC 5041. To my surprise, it ranged from 50.66mm to 51.95mm. Here is a picture of springs where you can see the 1.25mm difference.
Middle 2 are 1mm taller.
Next step is to measure each gap between valve spring seat and new titanium retainer and match up the best I can using shims (if necessary). I also ordered a valve compressor scale to put in vice and see if the compressed springs exert the same pressures at installed gap and compressed gap (from S2 cams). This is a lot more work than I thought initially. LOL
S2 cams and springs/retainers are in. Ended up not being able to consistently compress the springs to get any meaningful pressure readings. Springs compressed at a slight angle and it took too many tries to get it straight. Didn't have the time to do it for 16 springs.
Then during installation, I couldn't use the spring micrometer to measure each spring height because diameter didn't fit on evo head (darn!!). I did measure the top of retainer to top edge of head and found that the keepers can make retainers sit as much as 0.4 mm lower if not installed at its highest setting. I think it will move into place when engine is rotated, but I didn't want to risk the keepers popping out, so I released all the low readings and adjusted the keepers to sit at highest point. There is a height difference on 0.2 mm between all my installed valves (which is about 10 pounds difference at rest and maybe 20 pounds when compressed by cam, remember, there is a 1.7 factor from rocker arm, so cams will see 11.8 pounds of the 20).
Installation notes:
I tried using compressed air to keep valves up when replacing but that doesn't work well. In fact, it didn't work at all for me. Valves need to contact pistons to break the keepers free from stock retainers. So keepers with piston down position were stuck. When I was thinking about rotating the crankshaft, I noticed piston moved from the compressed air and SCREWED up my timing! UGH!!!. So I ended up rotating crank to TDC for the valves I was working on and abandoned the compressed air technique. I took a look inside the spark plug holes with a boroscope and saw a LOT of moisture buildup on piston walls. I don't recommend using compressed air!! Just rotate pistons to TDC for each valve you're working on and it can only drop 5 to 10 mm.
Resetting the timing belt was a pain because the front balance shaft was off a tooth one way and then the other way after adjustment. It felt like it should be midway in between. After resetting 4 times, I realized it was off because I didn't tighten the tensioner pulley enough both times I had it right.
Car is running and cold idle is crap since cams are letting in more air. Once engine warms up, idle stumbles every so often. Light boost to 3 or 4 psi was at 12.0 AFR.
Tuning is this Friday and I need to do a boost leak test to 30 psi again. I also want to do compression test to get a baseline of where I am with S2 cams. I was between 145 and 155 with stock cams. I noticed that intake idle vacuum dropped from 16-18 mmHg to 12-14 mmHg, which was expected. I borrowed my friend's SpoolinUp so I can test the difference Friday. I'm making my own COP from Honda but I won't get the connectors in time. Boo!
If any of you guys have any suggestions to help me plan for tuning Friday, please let me know!!!!
Last edited by 2006EvoIXer; Jan 24, 2018 at 03:30 PM.
Dec 5, 2017, 07:50 AM
