FP1x Cams?

[TSIfreek]

First thing I would do is replace the knock sensor. From the factory they are very tight and the sensor is more sensitive the tighter it is. I understand were you are coming from with the cam change being the problem but the cam only leans the motor out a little from added duration so a little more fuel may be needed but I question that with the FP1 cams.

 

[daren_p]

Well I'm running out of idea, so a new knock sensor was on my list in the spring (when the cars out of storage) just to rule that out. Was also going to take my injectors out & get them cleaned just to make sure ones not flowing less then it should be (only used for 2 summers). I don't have to worry about the effect of the cam leaning the motor out as my DSMLink is adjusted for the cams to have the proper fuel trims & I have a WB for the WOT pulls so this isn't an issue & I don't have the FP1 cams, I have the 1x (same lift as the FP2's with an increased ramp rate )

 

[TSIfreek]

Yea I know your fuel is all there using a WB so you can take that out the equasion. Sucks not haveing your car all winter its like loosing a body part.

 

[bearman]

you might try checking the ground on the O2 sensor or recalibrating it. It just seems to me that 10:1 is waaaay rich. My car (stock cams) starts missing at anything richer than about 11:1. I guess what I'm saying is that maybe your O2 guage is reading richer than reality. mine (lc1) was doing that once, the way I found out was by checking my gas milage. my milage was the same but the guage was reading rich. But whatever, if your car needs 10:1 to run good then give it 10, you definitely don't want it to run lean.
bear

 

[andymoraitis]

Daren,

I had very similar issues when I put the Comps in with the 16G and the 190. She knocked very badly. If you're not reading free rev knock and you don't have part throttle knock, I would treat the knock as real and verify this by adding higher octane gas. If it goes away, it's definitely real.

What solved the issue for me was a fuel pump change to a 255. Now I know that you already have one, but what kind of fuel pressure are you pulling at idle with the vacuum line off? It might not be a bad idea to also remove all of the fittings from your AFPR and teflon tape them, especially the main adjustment screw. If there's any kind of vacuum leak under boost, the FPR won't rise at a 1:1 rate and you'll run lean up top. I'd also re-wire the pump just in case and also check for proper voltage to it.

There's no reason that you should be running that lean on your setup and those boost numbers.

Keep us posted and hang in there,

Andy

P.S. I need to edit my vacuum numbers. With the intake cam advanced I see 9 in/hg at 1000 RPM and the idle is hellatiously wicked.

 

[daren_p]

Andy, Can't give you exact numbers because the cars now in storage for the winter but off the top of my head: Running the 255HP pump, rewired & when I did the pump install, I was seeing ~14.4 volts. Boost leak test is good on the car & the adjusting bolt on my FPR is already sealed. My base pressure is set at 44 psi and with the vac connected I think its around 37 psi. If my FPR wasn't rising 1:1, should this show up on my WB? I now see 13.5-14.5" VAC on my boost gauge but looks like its abit low, most of the time it sits at 14.5 which read right around 16 "VAC on a more accurate gauge.

The thing that has me stumped is it just started hapening when the cams were installed. I was thinking maybe one of the injectors is flowing less then its supposed to, causing knock in 1 cylinder, but the others are flowing correctly, so my WB reading would look okay. I'm going to pull my injectors & get them flow tested in the spring & veryify the FPR by applying pressure to the boost reference port. I'm pretty sure it is real knock but couldn't verify as last time I went to the track they ran out of race fuel just before I went to get some. I'm running the NGK 7's, was gapped at .28 & tried .25 with no difference. I was going to swap plugs & add some Magnecore wires (Accell thundersport wires are 3.5 years old but I do get a random missfire, maybe once a week if that) next spring & replace the knock sensor just to be sure.

 

[pickens]

Did you ever solve your problem?

 

[daren_p]

Yes & no I'm leaning towards just the fact that because of the profile of these cams they tend to be abit more knock happy compared to some other cams on the market. We all know cams create more cylinder pressure, which is a good thing but it also makes it more likely to knock. Seems these cams create alot more cylinder pressure compared to the "std" upgrades out there, so on pump gas their going to be more "knock happy". These cams are designed to really make the power in the 4000-6000 range & the area where you see peak cylinder pressure is in that range, so this doesn't help the situation.

With my FP3052 I could run about 18-19 psi & had to pull a good amount of timing to keep knock under control & usually saw 14-15 deg at redline. I added a meth injection system this past summer & it really help me out in the knock department. I was only running a small M5 nozzle with a 50/50 mix but it allowed me to run 22-23 psi & add a bunch of timing back to see 17-18 deg by redline. At the track I add a bottle of NOS Offroad Octane Booster & have run up to 26 psi without any knock. I think it boils down to these cams are on the aggressive side to be run with straight pump gas but add some meth injection or higher octane & you'll be impressed with the results

My knock sensor is origional, so was planning on swapping it out this spring with a new one when I swap intake mani's. Have heard people say their installed rather tight from the factory, making them more sensitive. So may make a couple pulls without the meth to see if a new knock sensor has any effect. I will probably swap the M5 meth nozzle to a M7 or M10 to get abit more out of it & hopefully won't have to run any octane booster at the track with the higher boost levels.