Too bad you just missed the June VHF contest on June 8-9th. I recall actually winning the LA section around 35 years ago, from the top of Mt. Pacifico (you can drive up to the campground up there). Most mountaintopping VHF operators go for the June, September, or January VHF contests.
There is some VHF activity on Field Day also, but it won't be quite as busy - most field day activity is on HF. And in general most VHF contest activity is on SSB with horizontal antennas. FM activity exists, but won't be as popular.
Download the Field Day rules at http://www.arrl.org/field-day
, and the general VHF rules: http://www.arrl.org/general-rules-for-arrl-contests-above-50-mhz
Don't use .52, but otherwise stay on recognized simplex channels for your area (assuming you can't do SSB). From the general VHF rules:
"1.8. Use of the national simplex frequency, 146.52 MHz, or immediately adjacent guard frequencies, is prohibited.
1.8.1. Contest entrants may not transmit on 146.52 for the purpose of making or soliciting QSOs.
1.8.2. The intent of this rule is to protect the national simplex frequency from contest monopolization.
1.8.3. There are no restrictions on the use of 52.525, 223.50 or 446.000 MHz.
Participants are, however, encouraged to not monopolize the calling frequencies throughout the contest period.
1.9. Only recognized FM simplex frequencies may be used, such as 144.90 to 145.00; 146.49, .55 and .58, and 147.42, .45, .48, .51, .54 and .57 MHz on the 2-meter band.
1.9.1. Local-option simplex channels and frequencies adjacent to the above that do not violate the intent of the above rules, or the spirit and intent of the band plans as recommended in the ARRL Repeater Directory, may be used for contest purposes."
- Jim, K6JH