Lingenfelter Pulley upgrade LSA from 555hp to 630hp

[DarkSide]

Hulk, that's full 2850lbs OEM ballast plus approx 1200ish(~700 in a trunk, and ~500ish in lead, batteries etc).

So yes, as you increase dia(keeping pitch the same) you will likely decrease your top speed as it becomes drag in the water over 30mph in the 15"+ range. I lost 1-2mph going to a 16" dia from 15". But you will gain some of that top speed back with increased 16-17" pitch if you go that route.

The RPM drop and the increased performance are well worth the slower 41mph top speed. 16x16 will likely give me that ^^^ same wave in the 2600rpm? range, and I might get 1-2mph back at top speed to 42-43mph.

Ryan,

You are seeing a noticeable drop in RPM for same ballast setup. Have you noticed a difference in fuel consumption as well. I know last year you did very detailed log of this data. Just curious how the "correct" prop effects fuel consumption.

If i am understanding correctly, the highest diameter and pitch you can get, while achieving acceptable performance, will be your best efficiency?

Edited May 15, 2015 by DarkSide

[nyryan2001]

Dark, yes I believe that to be true.

So for me, 40mph top speed is just fine. I cruise the lake at 23-25 when transiting anyhow. Rarely go above 30mph. I averaged 7-9gph last summer.

So for 40mph top speed, I want the lowest RPMs possible for any given activity, with the best performance in that range.... Without over - prop'ing.

Over -prop'ing = can't achieve 5300+ rpm or slower/lagging launches when sac'd out

The 550s have so much tq the OEM 15x14.25 was like running in 3rd gear.

The 16x15 gave me 2-500rpm lower for every activity. I still got 5450rpm with that and faster 0-23mph launches when sac'd out. It has the tq to sling the larger prop. I am near convinced RPM and GPH have a linear relationship, ie there is no situation where 2900rpm will use LESS gas than 2800rpm.

The OJ 16x16 just arrived... We'll see how that does this weekend.... But I should be surfing my wave in the 2600rpm range right at the lower tq band of the 550, we'll see. I'll report back gas usage.

But to answer your question... For how I use my boat. Max diameter first then even up pitch if hull clearance will allow.

[nyryan2001]

Errrr, I mean 16"x15.5" !

[nyryan2001]

So the 16"x15.5" performed terrific. Dropped RPMs another ~150+ across the board.

Surfing my standard wave today at whispery quiet 2625rpms.... vs 2950-3100 on the OEM 15x14.25" prop.

Was still able to launch out of the hole like a rocket, and the engine was still able to achieve 5450 RPMs. It could handle a 16x16.

[The Hulk]

Bu needs more clearance. ... jealous! Need to get the 15.25x16-17 when ready!!!

[The Hulk]

called OJ, there is NO 15.25" diameter, he said 15" max on the bus as of a wee or two ago.

He suggested that i go with a 15x15 with my 23 lsv but said he could do a 15x16 but it might not be going as well. His reason was that the bus have a wedge and nyryan g23 does not have that serious wedge drag like the bus.

Current set up for me is

Prop = 1235 (14.5 x 14.25 @ .105 cup)

Full Stock Ballast

Wedge 1-2 clicks up from full down

550s x 2 in rear lockes

Bow sack 1000lbs (that i put in center of boat because putting it in the bow kills wave)

4-6ppl in Boat and i'm typicall 2600-2900rpm with the LSA 555hp,

NOTE the wedge makes a 200-300rpm difference based on angle of attack which can change with placement of people in the boat and qty of people. Sometimes i'll notice getting close to 3000rpm and i'll click wedge down one notch and it will go back to 2600-2700 range quickly.

Desired set up

prop = ??????

Full Stock Ballast

Wedge 1-2 clicks up from full down

upgrade rear lockers to 750s-800s x 2

put bow sac 1000lbs in the Bow! to save floor room!

so the question is going up to a 15" prop do i go with 15" pitch or 16" pitch? OJ seems convinced a 15x15 would be safer than a 15x16... any thoughts? and cup does .105 vs .150 make a difference?

still wish to hit 52mph if possible for those fun WOT moments of hearing the SC scream like a jet ....but not critical. i'm guessing going up in diameter but also going up in pitch i should come out the same roughly, maybe even faster top end with the 15 or 16" pitch? since i cant sling bigger than 15" diameter going up in pitch might actually help top end, what are your thoughts taking note that the bus have the "draggy" wedge? obviously lowering surf rpm is key importance, but we also slalom here and there, and may get into some bare footin! so haul shot is nice!

Edited August 4, 2015 by The Hulk

[nyryan2001]

On 5/19/2015 at 8:39 PM, The Hulk said:

Bu needs more clearance. ... jealous! Need to get the 15.25x16-17 when ready!!!

Did you ever change the pulley?

so this last weekend... has to replace one of my belts at ~330hrs as it was chirping.

i had no idea how easy it would be to swap the supercharger pulley.  Probrably in under 5 mins.  

 

pull back the tensioner, unloop the belt.  Unbolt and remove pulley, install new pulley, replace belt..... done.

it truly would be that easy.

[The Hulk]

8 hours ago, nyryan2001 said:

Did you ever change the pulley?

so this last weekend... has to replace one of my belts at ~330hrs as it was chirping.

i had no idea how easy it would be to swap the supercharger pulley.  Probrably in under 5 mins.  

 

pull back the tensioner, unloop the belt.  Unbolt and remove pulley, install new pulley, replace belt..... done.

it truly would be that easy.

No, I traded that in for the 25lsv. After the second season after the first when water hose wasnt hooked up... the "epic thread" the second season started off ok but performance lacked , few trips back and forth i got tired of messing with it. the mechanic was out for several weeks so i just traded in for the 25lsv. Ended up all the head gaskets needed replaced and that fixed it up right again but i got tired of missing summer weekends.. 

yes i discussed with several people its pretty much just that easy , probably 10 min job for you, 30mins for normal humans! ha. 

i discussed with someone who discussed the issue with a lingenfelter guy,He mentioned its super easy, but if you can also do a street tune it will be even better. I had a guy that was going to bring his lapotp out and do it on the lake... would have made the BEST surf boat IMO. I mean i was already surfing at around 2600-2700rpms. and that was with an underpitched prop. Adding all the low end power and pitching up i could have easily dropped several hundred more rpms.

I MISS my low rpms surf and cruising. Now cruising and surfing i'm 4k+. Granted my wave is better but i miss the high pitch jet-engine sound! the response was insane even on a 1.25:1 ratio

the trannys are so geared down (i understand why) but i think there is a lot to be said about a SC engine and getting all that power at the low end.. IMO these boats have crossed the middle ground and have gone too far into gear reduction and not enough into SC engines. Look at the F150s everyone laughed when they launched their SC 6cyl. But my larger f150 ecoboost blows my 420hp Denali out of the water for pickup. who knows maybe someone will throw an eco-boost in a wake boat for a test someday! ha.

i think a 630hp pully upgraded SC LSA with a 1.50 gear ratio throwing a higher pitched 16" prop would be a killer combo for surf boats.