I have a 22' tunnel ech Mach 22 with a 500 up. It came with fixed manual adjustable trim tabs. I think they are way to far down currently in line with the tunnels. But not in line wIth the drive at speed. I think that is causing the boat to feel heavy at speed pushing the front down at speed Ive never had these before so not sure how to adjust. I wa thinking lift them up all the way and See what the boat feels like first

I'm graduated with a bachelors in Mechanical Engineering. With a tunnel Hull, having the front of the boat "front heavy" is more advisable than the opposite, especially at speed. If you make the front tires on your car super light, you lose control easily..the same can be said for you boat. At full "up" position, your boat may take longer to get on plane as well. I'd opt for moving up in small increments as opposed to the opposite. Lower your risk for mishaps during the feeling out process. Just my two cents. There may be a better setting for your tabs than they way they are set now, but at cruising speed it may perform entirely different than it does at wot.

Thanks for the detailed reply. The previous owner installed them as he said the boat would porpuse at slow speed especially due to the heavy engine in a small boat

Boat was under propped and was bouncing off the rev limiter ans I went from a 26 bravo to a 30 bravo and gained around 8 mph. So I don't think boat was really set up to max mph

I'll try moving it up in small increments and see how it feels

Not sure how easy it is to flip a tunnel like mine. DCB said the boat can run 130 mph safely. (I'm 87 so way under that speed)

87 mph in a 22 has to be a Wild Ass Ride??! 130 MPH may be possible with your Hull Design, but Holy Hell if something goes wrong at those kinds of speeds. Most boats would delaminate at those speeds! Cavitation or "porposing" is caused by the imbalance of friction against the bottom of the boat. 87 mph is awfully fast, I would consider being very specific, actually Very Scientific in how you distribute any of the weight around your cockpit. (It'd be like having 20 lbs. Of pressure on the right side tires of your Lifted Jeep with 45 lbs in the other side, then taking a shap turn then overcorrecting to the spongy side) Tunnel hulls will tend to crab walk before they flip giving you just enough time to throttle down but a large unexpected wake or windswell might get the front up far enough to ruin your whole day. Have Fun and be Safe! I've got a week and a Half until the resto on my Pachanga is done, it's a 22 but it'll never see 87 mph..LOL

It's an odd feel, feels like nothing, smooth, stable. My V bottom Eliminator is one wild ride @ 82, flies high and balances on the flat pad, what-a-rush!

I lifted the tabs about an 1", now the boat feels MUCH better, and the trim acctually does something now.

The 22 Pachanga, that was a cool boat, and still is a cool boat! THe guy who helped my gain 10 MPH on the Elimnator said the 22 was one of his favorite boats (in that size) With a stock 502 and imco 2" shorty he was getting 72, and superchared 85.

I raised my drive 3" on the eliminator and went from a 25" 3 blade mirage to a 28" 4 blade bravo. Can run a 30, but not as much fun mid range

What set up do you have on the Pachanga?