'07 RXT SC Rebuild Water Test

[door54]

Unit ran very well...smooth and responsive. I was surprised that it only topped out at 7800 (70 on the dreamometer).
water- 85 and smooth/flat
air- 100 w/ 0-3 mph wind
elev 1079'
tank full of 91 (aged to imperfection)
rider 6' 222

On the river below the dam on day 2.. water was much colder, air about the same temp but blowin enuf for white caps. Performance quite similar. Good enuf to get me grinnin' but just a bit low on R's and top end. Wild horses out of the hole though...cutting tight when dumping it left or right..up to a point, too fast and the ass end was coming around on me and burying the stern. I was lovin those sticky grips a few times. lol I think it's time for an intake grate

 

[mattydipps]

Unit ran very well...smooth and responsive. I was surprised that it only topped out at 7800 (70 on the dreamometer).
water- 85 and smooth/flat
air- 100 w/ 0-3 mph wind
elev 1079'
tank full of 91
rider 6' 222

the air temp and water temp is what kills rpms in the summer time.. i loose around 300+ rpms in the heat.. today i was hovering around 350 rpms less then usual with 102 degree air and around 87ish on the water

 

[door54]

the air temp and water temp is what kills rpms in the summer time.. i loose around 300+ rpms in the heat.. today i was hovering around 350 rpms less then usual with 102 degree air and around 87ish on the water

Long Island and 102? yeesh How wet is the air? I can take our famous 'dry heat' all day long but we had our first T-storms yesterday along with an initial 106..it was just suffocating till it cooled down a bit

 

[mattydipps]

Long Island and 102? yeesh How wet is the air? I can take our famous 'dry heat' all day long but we had our first T-storms yesterday along with an initial 106..it was just suffocating till it cooled down a bit

It sucks man.. Today only got up to 93 but the last 6 days we've been hovering at the triple digit mark with heat index well into the 100s

Humidity has been bounced around from upper 40% to low 60%.. They say its a record setting hear wave from the last 7 days... it hasnt rained in over a week and never thought I'd say this but it's even too hot to ride my ski.. Go out for 10 minutes and your burnt

 

[TheGunMan]

Unit ran very well...smooth and responsive. I was surprised that it only topped out at 7800 (70 on the dreamometer).
water- 85 and smooth/flat
air- 100 w/ 0-3 mph wind
elev 1079'
tank full of 91 (aged to imperfection)
rider 6' 222

On the river below the dam on day 2.. water was much colder, air about the same temp but blowin enuf for white caps. Performance quite similar. Good enuf to get me grinnin' but just a bit low on R's and top end. Wild horses out of the hole though...cutting tight when dumping it left or right..up to a point, too fast and the ass end was coming around on me and burying the stern. I was lovin those sticky grips a few times. lol I think it's time for an intake grate

I have same problem

Where are you located?

 

[door54]

I have same problem

Where are you located?

What problem is that GMan?

I'm located in the Vegas valley.

 

[TheGunMan]

Rebuilt charger and ~7600 rpm

I am in Vegas too

 

[KK40384]

If it makes you feel better mine ran 7860rpm on Saturday with 95* and 70% humidity. Sunday temp dropped to 78* and low humidity, I was turning 8100rpm. Water temp and wind were about the same.

 

[TheGunMan]

I was on the lake saturday and turned about 7700-7800.

 

[red2blue]

You guys need to check your rad when trying to chase rpms in the heat ect...

http://wahiduddin.net/calc/calc_da.htm

Oh, and a lower thermo will help keep heat fade to a minimum.

 

[door54]

Hey Red-

Great link, thanks.
I never really have paid to much attention to top end R's or mph thru the years, as long as it performs well enuf for me to keep a healthy respect for what it could do to me if I become seperated from the seat at speed.
I have read a fair share of "I'm thinking about buying" threads where the forum recomends a water test before buying (of course) and getting the unit up to speed and holding it at 8000+ for a period of time. It dawned on me that I never did that with my own lol! So I figured after JG rebuilt the SC's would be as good a time as any to run 'em up and see where they went.
Stands to reason hot air and warm water would have a degree of impact, I just didnt have a pespective point from prior runs to make a comparison

 

[Michael211_2000]

Water smooth as glass adds drag to the thull also... best performance is with a light chop, so the water surface isn't so "sticky".


+ or - up to 100 rpm's either was is irrelevant to my fun, as long as the engine is running smooth and strong I'm quite happy doing tight donut's and "porposing" all day long... I've never gone 100% full throttle on mine, no reason to (but been close to it a few times for a minute or so).

Regards!

ps. Fill your ride plate bolt hold recesses, they're a real drag! A good performance intake grate and a pump wedge make a ton of difference at all throttle settings IMHO!

- Michael

 

[door54]

Hey Michael-

Been a while.
How do you define light chop? I prefer the water suface to be disturbed. When on the water when its smooth or glass, my ride has an inherrent rythmic port/starboard rocking motion at cruising speeds. Drives me nuts. Can make me woozy. Just wont balance on top of the fulcrum lol.
So far as WOT is concearned, I don't think I've intentionally gone flat out and held it there, more than a couple of times since I owned it. Not my style. I'm more of a hole shot, short course rider.
Ive read many responses that the veterans on this forum offer up to newbies when they have questions regarding puchasing used SC rides. And one of the recomendations is to pre ride it and make sure that it hits rpms in the 8k range to validate the SC. It dawned on me that I never really put mine thru a deliberate trial run...so I did. The unit runs great, and like you, if its happy then I'm happy. Top end R's arent part of my personal satisfaction equation, unless of course something is not quite right.
JG did a great job on the rebuild..for what $75? Cant go wrong there. Certain things I can let go of and not do myself. Got too many sticks in the fire as it is.. lol

good to hear from you

 

[Michael211_2000]

Hey guy!

Light chop? Well, if you can go fast on it without feeling like you're riding a bucking bronco then I guess I'd consider that "light chop". LOL! I don't know how else to describe it honest... you want enough surface agitation to create air bubbles as your bow goes over the surface, the bubbles reduce drag (why modern high performance boats have that ragged bottom shape to them, they are inducing their own bubbles by design).

7800 rpm's is well within my expectations if you have a well loaded pump with a good tight wear ring (perhaps a Solas performance impeller as well). Mine's engine was in pieces when I bought it used, so I really had nothing to lose (the price was right for the hull and trailer only, with the assumption I might have to buy a rebuilt engine... but I was able to fix it and it runs great!). However you can test your SC on the trailer by taking the seats off starting the engine then gripping the SC to TB (throttle body) air hose while slightly rev'ing the engine for a few seconds... you'll feel the air hose expand under your grip, a good sign the SC is making boost (yes I KNOW it's not scientific to those who'll comment, BUT it does tell you if the SC is working or blown and that's all I'm checking for when I check mine this way!).

I've never gone WOT either, but close to it twice now and it was in the high 7700's @ ~67mph for the short time I had it that fast. Still had room to go faster, but that was more than fast enough IMHO. LOL! My riding style is splashing around doing donuts and porposing it (making it go partially underwater for a second then popping back up).

I've never heard anything but good about JG's work at GH, he knows superchargers like the back of his hand I figure that's where I'll send mine this next winter.

- Michael

 

[Michael211_2000]

ps. The R&D Aquavein intake great has really nice tall rails, it makes my RXT ride like it's on "rails" it tracks perfectly straight and turns on a dime! And I just put an R&D 2.5 degree pump wedge in and tried it this weekend... very nice, really leans into tight turns just like it was on a race track with banked turns and I no longer feel like it's "bulldozing" it's way across the lake surface the bow now comes up nicely with a much improved ride! I love it, I just need to find more time to go ride now dang-it.... lmao! ROF! ;-)

- Michael