Thread: Limited SP STX-R speeds
06-23-2010, 08:16 PM #1
Limited SP STX-R speeds
Ok im wanting to some input on this setup and what speeds i should be expecting as im still dialing in the boat but wanting to know this setup peaks potential. Im being told 65 GPS but not exactly sure.....
single pipe (stinger mod), pump gas (93oct) 42cc heads (120-130-120) center cyl is new , 48 novi carbs with D-booster, Delta V-force 2 reeds, 14/24R prop with stock pump, aftermarket Intake grate and ride plate, beach house sponsons and triple fuel pump and pickup.
61.9 has been the best ive gotten out of it but like i said im still dialing the carbs and ordering a new tiny tach and egt for it for better tuning. Hoping theres more top speed to go and what im missing to get it
if anyone has other IJSBA limited mod ideas please let me know but im trying to stay pump gas single pipe and just trying to squeeze as much as possible out of the boat with the single and pump setup. Any help or input is greatly appreciated!!!
06-23-2010, 08:28 PM #2
pm jonny5 he should be able to get you some informatioon
06-23-2010, 09:47 PM #3
06-23-2010, 10:06 PM #4
just read through some of that thread and right off the bat i noticed the stock speeds and speed further posted to the next page are already higher than mine. Are these GPS speed or the "Dreammeter" speeds. I have seen myself a pure stock STX-R with the same GPS i used on mine only do 57 so thats where im getting somewhat concerened on all these threads and websites stating there speeds vs. mine. Im still gonna read the thread till the end. Are most of these things im reading and seeing GPS talk or the dream meters speeds?
06-23-2010, 10:19 PM #5
06-23-2010, 11:05 PM #6
Someone mention me...??
Yes all gps and try to go to the same location using back to back info and also try to stay at 1/3 of a tank on the fuel.
Read my thread it will provide alot of info. Alot...!!
If you can give a little more detail on your exact setup like
R&D intake or worx and if R&D which one?? What plate... I assume stock nozzle.
These stxr's are hard to get speed from. Also what year is your ski.
The novi;s may be hard to tune in on the bottom correctly as the novi's provide such a blast of air that the motor cant compensate, unless you jet it really fat but it will be lazy on the bottom.
PLus I did the novi thing if you read my whole thread and they just loose the signal at low idle speeds and sometimes can just kill the motor when going from idle to punching it.
Just from what I am reading and if you just bolted the stuff right up to the bottom of your ski I bet 62 to 63 mph...tops.
Just to let ya know I just got back from the water tonight....and my latest setup which is my CC setup with stock plate all "Sealed and matched to my hull" <<< Notice this
Ran a 64 mph flat with a 2 degree nozzle and the stock is 5 degree's..
And tonight I tested the R&D ride plate ...I took it and bolted it up and it fit poorly with some front edge overhang and of course not sealed.
I ran with just the plate change only 62.8 for a high ...how ever it was humid and about 98 degrees out so thats at least a .5 mph lose or more.
Ethier way the "just bolted up to the hull plate" ran slower than my fully matched and sealed stock plate.
Keep reading and you will find and see alot.
Let me know if you have questions.
06-24-2010, 06:07 PM #7
First off thank you guys for the response as they are VERY much appreciated. Well read all 25 pages to that thread lol took awhile and it has answered several what ifs and maybes i had in mind for the ski. So its back to the testing of the carbs to get those right and the tiny tach ordered. I am by the way running the R&D rideplate and R&D intake grate which it does do its job on the course. The pump assy. is all stock except the prop which is the 14/24R so with that being said and how the courses are getting larger for the 4 strokes high speeds would it be in my best interest to go to a higher speed prop or will the one do me just fine. My class typically is the XPL's and once in a while a 15f just wandering if i should go back and change the pump and prop or just prop? the stretches seem to be were i get ran down and passed at by those boats and well.......just cant have that lol. Once i get the tach in ill keep posting on how things are going with mine.
07-11-2010, 06:18 PM #8
Well finally got the tach in and did about 13 different test runs to see if i could get the rpm up any and after all the runs my Average rpm's were 6892/ lowest was 6670 with a high of 6926 but mainly in the 6895 for the vast majority of the runs. I am running a large main jet as afraid of melt pistons again so i know that could perhaps be slowing the rpms some. So now im on the next bit of the project for the tuning but am a halt for the EGT's location in the Exhaust manifold. noticed that the setup is pretty much a inner piped and outer pipe with the center being water cooled and cant determine and how exactly to equip each cylinder with a egt port......ANY ideas????
07-20-2010, 05:11 PM #9
Well i guess im gonna put off the egt ports on the stock manifold off until this winter as Nationals is creeping around the corner so gonna put the exhaust and all the other stuff back together and get back to tuning.
Users Browsing this Thread
There are currently 1 users browsing this thread. (0 members and 1 guests)
By BGslugger in forum 4-Tec PerformanceReplies: 8Last Post: 08-07-2007, 01:29 AM
By Flynfox in forum 4-Tec PerformanceReplies: 8Last Post: 07-12-2007, 06:42 PM
By happyappy in forum Kawasaki Open DiscussionReplies: 0Last Post: 06-13-2007, 03:02 PM
By sleeplessnMS in forum Yamaha PWC Performance (2-stroke)Replies: 22Last Post: 04-10-2007, 06:04 PM
By Woody49 in forum 4-Tec PerformanceReplies: 13Last Post: 02-16-2007, 10:11 AM