Hey guys, finally finished the rebuild on the B17 and she was running fine until yesterday. I’ll try to make this as detailed, but simple as possible.
VTEC in my car wasn’t kicking in at all because the 2 wires on the Engine Coolant Temp Sensor connector were severed…fixed that, VTEC started engaging again (it’s only been 2 days since it’s been working); all was good.
I’ve been breaking in the engine so I didn’t rev past 5k RPM up until I got the VTEC working at which point the engine already had 650 miles on it. Due to the mileage I figured it’d be safe to rev a little higher to make sure the VTEC was working properly. I did so, but haven’t rev’d it past 6.5k RPM.
Yesterday, I noticed that as the VTEC crossed over, the car bogged hard at both partial and full throttle. The engine has about 750 miles on it now.
There some differences though between his set up and mine. I’m only listing mods that might be relevant to the issue:
B17 Bored .5mm over
9.0:1 CR Pistons
CTR Cams
B&M FPR (I set it to about 50psi)
Stock ECU
Car runs great & strong until the crossover 5.8k RPM. I should also mention that I rebuilt this engine for boost and have not had it tuned; mainly because I figured I’d wait until I got it boosted (won’t be for another month or two).
Car idles at about 800 RPM. I have not advanced the timing so all settings, with the exception of the fuel pressure, are stock. I realize the CTR cams may be playing a part in this bog issue, but I’m no tuner so I haven’t tried advancing or retarding the cams.
Any suggestions on things I can do to troubleshoot the issue myself? There are no CEL codes being thrown. Any help is appreciated as always. Thanks in advance!
TUNE TUNE TUNE. if you dont plan on tuning it until boost, thats fine, but dont be revving it out and not expect problems. Honestly I would associate any odd driving flaw with bogging or any rev-related problem with tuning. it seriously makes the world of difference. what are you using for tuning? maybe you should just find somebody to get a few hours in around the street just to ensure you don’t do any damage to your new motor?
…just a thought.
ps, in the event you do want to sell your CTR cams for more turbo goodies, lmk.
If it wasn’t for the $125/hr the tuner (Lo-Cash Racing…recommended by a lot of people and AZ forums; apparently they’re the ish) is charging I would take it in as soon as I completed the 1k miles breaking period.
I guess I’ll just continue breaking it in and not take it to the crossover point. Thanks bro!
Yeah, I agree with both of you guys. I didn’t just drop a gank o’money into the engine to have it go boom. I’ll have it tuned after the break in period and after the turbo install. Appreciate the input!
i honestly didn’t take the time to read everyones post, im just wide awake and want to let you know what i did.
i have a b18c with a stage 2 head. i bog is my vtec eng is any lower than say 6200 RPM’s. i dont know why but if i slowly depress the pedal i can tell.
so i raised it to around 6300 or so… although it helps if you can rev to 9200 lol
…once i revved to 10,100 RPMs…that was a big oppsie. lol
50 psi is kinda high.
38 psi = normal.
40-42 = lots of mods.
50 psi = alot of fuel and pressure.
Once, I adjusted the fuel pressure to 48 psi and had the same bogging issue when I hit 5500 rpms [vtec switch over], on the stock ecu.
Any updates??