Page 1 of 2 1 2 LastLast
Results 1 to 10 of 12

Thread: 370hp mods?

  1. #1

    Join Date
    Sep 2012
    Location
    Nashville, TN
    Posts
    129
    +1
    1

    370hp mods?

    Guys, Im currently looking to sell my trusty Yamaha Exciter 270 and get into a Speedster 200. I know I absolutely want/need the 430hp model but Im seeing some 370hp models for real good prices. Right now Im at 61-62mph on my exciter and I told the wife that the next boat HAS to go 70+ what do I need to do to the 370hp model to get it past 70?

    If I picked up the 430hp Model I had already planned on doing the ET127 wheel and 43# injectors. Ill build my only 4" cold air kit. still not sure on what impellers to get tho.. With that in mind can I still do those mods and just replace pistons in the 185hp motors? Is the 185hp blower that much different than the 215hp?


  2. #2
    Tiny's Avatar
    Join Date
    Sep 2006
    Location
    The Atl
    Posts
    3,561
    +1
    578
    Make sure you ride in the boat before you buy it....The hull DOES NOT LIKE CHOPPY water!!!!!

    I did a build where I took a 430 and turned it into a 510....Lots of power, props are a pain in the ass, lots of cavitation and then there is the handling....But like I said above, ride in it before you buy it....

  3. #3

    Join Date
    Sep 2012
    Location
    Nashville, TN
    Posts
    129
    +1
    1
    Quote Originally Posted by Tiny View Post
    Make sure you ride in the boat before you buy it....The hull DOES NOT LIKE CHOPPY water!!!!!

    I did a build where I took a 430 and turned it into a 510....Lots of power, props are a pain in the ass, lots of cavitation and then there is the handling....But like I said above, ride in it before you buy it....
    I followed your build and you did some great work! Im hoping to follow Jstcdoit's footsteps and get a real trim setup to work. Im a mechanical engineer by trade and a fabricator in my spare time. Im hoping that will solve the bouncing issues. Ive rode in the 150 speedster with the 215hp engine and while I thought the ride was on par with my exciter the inital punch and top end speed was seriously lacking. Im willing to work through some ride issues to get the power, speed and looks of the speedster. If anyone out there is in middle TN and would like to meet up and go for a spin please let me know. I have never seen a speedster 200 on the lake nor do I know anyone with one....


    What other jet boat with fairly mild mods can do 70!? I would love to have a Yamaha 212SS but they are just to slow and modding is almost non existent...

  4. #4
    Tiny's Avatar
    Join Date
    Sep 2006
    Location
    The Atl
    Posts
    3,561
    +1
    578
    I agree, he is building an interesting trim setup..If you have the time and and the knowledge, then it may make a real nice boat..

  5. #5

    Join Date
    Jul 2011
    Location
    Ct
    Posts
    158
    +1
    3
    Good luck getting past 70 mph with a speedster it can be done but at a cost. Like Tiny said the chop is going to kill your top end with it jumping out of the water all the time. I've owned both boats boats a 370hp. and a 430hp. Both boats are fast but the 430 has a better base line to start with. 430hp. has forged pistons so you will be safer to spin it faster and the flywheels are the correct ones to put xchargers or whatever style you choose.

  6. #6

    Join Date
    Sep 2012
    Location
    Nashville, TN
    Posts
    129
    +1
    1
    So what does it take to bring the 370 up to par with the 430? flywheel and pistons? Also theres tons of differing reports some say the bouncing isnt bad and that adding trim tabs solves nealy all the bouning issues while others like Tiny say sell the boat its junk.... Its a light boat and I understand its not going to handle the chop like a 20' I/O but if adding trim tabs or better yet gettting the VTS working solved the bouncing what else is wrong with the boat?

    Im a bit confused there are ppl on here that are saying they are getting 64-68mph stock? Is that not correct? I thoguht they were around 62mph stock and with mods getting to 70 wasnt THAT hard. If I got the 430hp model I thought adding a wheel, intercooler, injectors and a cold air kit would get me to 70? is that not true?

  7. #7
    Tiny's Avatar
    Join Date
    Sep 2006
    Location
    The Atl
    Posts
    3,561
    +1
    578
    The best I saw was 68 after all the mods I did and it was a rough ride..Had to keep backing out of the throttle to keep it in the water...I have worked on several of these and they all do it. I may be over reacting to this problem, but if i wanted to break my kidneys everytime I go in the boat i would have one...

  8. #8

    Join Date
    Sep 2012
    Location
    Nashville, TN
    Posts
    129
    +1
    1
    I dont think your over reacting its a valid problem. Lets say it is fixable with a trim system, what would it take to get a 370hp model up to the same level as the modded 430hp model? If its only about $3-4K It might be a very good option as you can find 370's for $10-$15K. Tiny, didnt you say your buddy was selling his? can you PM the info?

  9. #9

    Join Date
    Jul 2011
    Location
    Ct
    Posts
    158
    +1
    3
    You would need to change the flywheels ,chargers to get close to the 430hp. Then you are still spinning lower rpm then 430 version so boost will be a little down also the 430 has internal intercoolers not sure how much they do they don't look to efficient. Most of the parts can probably be found used on here for pretty cheap. My 370hp. Boat was pretty impressive I wish I clocked a top end speed before I sold it.

  10. #10
    Boost-A-Holic's Avatar
    Join Date
    Jul 2012
    Location
    Dallas, Texas, United States
    Posts
    1,173
    +1
    94
    i got a stock 215 intercooler layin around if you ever decide you need one!

Page 1 of 2 1 2 LastLast

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. What are your mod and results
    By Jrsrxp in forum 4-Tec Performance
    Replies: 33
    Last Post: 12-17-2007, 08:20 PM
  2. Water Box Mod
    By Red Devil in forum 4-Tec Performance
    Replies: 27
    Last Post: 05-17-2005, 04:56 PM
  3. RXP Mods?
    By dgmoore in forum 4-Tec Performance
    Replies: 8
    Last Post: 05-10-2005, 01:16 PM
  4. NEXT MOD IN SIGHT ~>>>>>>>
    By CRAZEDRXP in forum 4-Tec Performance
    Replies: 4
    Last Post: 05-07-2005, 07:27 PM
  5. My Mods and test results
    By CRAZEDRXP in forum 4-Tec Performance
    Replies: 14
    Last Post: 05-05-2005, 07:38 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •