liberator221

Your logic makes sense to me. Why don’t you wait to order props? See where you are with all cylinders.

Helmwurst

Are your trim indicator's in sync with each other?

PQ290Enticer

I installed mechanical indicators for this year and they could use a little more adjustment but I think we are talking a fraction of a degree. #5 cylinder not pulling its weight is the problem.

PQ290Enticer

You make a good point however these are borrowed props that "Rookie" was nice enough to let me use for the entire season. I might be able to borrow again in the spring for a final analysis but will not plan on it. I also want to thank BBYSTWY for allowing me to sit on a pair of 28's for the entire season. I feel as though I could order either pitch and be happy. The boat got on plane quickly with both sets of props, the mid range pulled like a freight train with both sets of props, and the top end was a little better with the 28's but the rpm was a little low. That being said, over the season with the 26's I have been trimming the drives out more and more and picking up speed and rpm along the way. If I get my port engine up to snuff and fully trim it out I think even with the 28's I'll be close to 5,000 rpm which will put me at or in the low 80's. That is really fast for an Enticer

liberator221

Right. Forgot that you borrowed props.

Rookie

I don't believe the plunger on 1 lifter will solve the 200RPM difference. But your logic does make sense. I'm dealing with a 400RPM difference currently. I have another set of new 26's, a set of Mercury Racing labbed 28's, a set of B Blades labbed 28's and a stock set of 30's. And of course the 26's you have.

hblair

I had a 30' scarab I restored. When I put it together I never could get the left engine right. It wouldn't turn the rpm's the right side would. The boat would run about 70mph, seems like the right side would turn around 5000, left side would be around 4500. We messed with the ignition, replaced plugs, wires, etc. Got into carb jetting, etc. Never could figure it out. 4 Years ago after getting back from a failed trip to the bahamas where I broke a left u joint, I pulled both drives off and for kicks and giggles, checked the drive ratios. The left drive ratio was like 1.32:1, whereas the right was the normal 1.5:1. This was how I bought the boat and I'm not sure if the previous guy even knew about it. I know this is unrelated to your situation, but thought I'd tell a weird story.

PQ290Enticer

Is the rule of thumb about adding or subtracting 2" of pitch equaling approx 400 rpm linear?? From my almost "$2,000.00 now experience" it's not. I am wondering if the jump to 28" pitch props is an exponential jump in the boating world.
Last year I borrowed a set of 28's and a set of 26's both B-1's and both sets of props didn't really match each other as a set whether different years and Mercury changed the style of the blades or maybe some repairs were made to one and not the other. The point is both sets were used, visibly different from each other and unknown history. Both sets ran fine in fact, both of these sets rendered better top speeds than these new ones.
Based on last years performance and my goal of running a WOT of 5k rpm I bought 28" B-1's. Seemed like a logical move because I was running around 53-5400 rpm with the 26" and the speed was 78mph. I was really hoping to bury my speedo at 80 with the new setup. I finally get out on the water with the new props and my speed is down to about 73 and the rpm is 44-4500. My disappointment at that moment couldn't be measured....
The first question is always about trim and I know there are variables so this is just FYI. I have the mechanical indicators for drives and I am just above 7 out of 8 so it's trimmed out pretty far and feels like it too. I don't have any problems getting on plane with the 28's and the mid range cruise is fantastic! At 3600 rpm I'm running 60 mph. That used to be my wot speed! Carbs are mechanical secondary's and are opening fully. I did bump the timing from 33 last year to 35 degrees all in this year. Normally that makes the engines run stronger right? AFR's are in the mid 11's. Last year with the carb issues I think the AFR's were in the 10's. It was pig rich everywhere.
So my question is whether its better (good idea) to have these 28's changed to 27's or just buy the 26's? Maybe a new set of 26's would run at the 5k rpm I'm looking for?
Neither will happen this season because the 26's were out of stock till the fall and I'm hoping to get some actual boating in this season and don't want to wait for these 28's to get altered.
As always, I appreciate your help and input.

Rookie

How many things have you changed since last time running 78mph with 26's and current new props?

hpmaniac

Bad ass! what is the engine in this?