Any ideas on 97.5 GSXL mods?

[Todd Adams]

Howdy,

I've been lurking for a while, checking out archived information and admiring the freedom with which information and advice is given in this forum. From the subject line you can see that I have finally decided to participate and am humbly asking advice from the gurus of this forum.

After the end of the season, I am looking to make a few modifications to my Seadoo. I bought the PWC new and have only occasionally ridden it over the past few years resulting in ~50 hrs on the hour meter. When I initially purchased it, I also bought an Inventioneering grate and modified Solas XI impeller from Bill at Watercraft Magic. Together, these two changes eliminated the cavitation problems. Other than that, there have been no other modifications to it.

I only have a few stipulations about the mods; It must run on pump gas (92), I would like a couple of mph on the topend (~64 mph) and I would like MUCH better acceleration up to that top speed.

Thanks in advance,

[Bill O'Neal]

Hi todd,

Do you have my rejetting kit, filters and a Miller head. Those items will do what you want, and all for under $500.00.

[Bill O'Neal]

Hi todd,

Do you have my rejetting kit, filters and a Miller head. Those items will do what you want, and all for under $500.00.

[Todd Adams]

Thanks Bill.

In addition to the modifications that you have suggested are there any other bolt on modifications that would enhance performance, other than exhaust?

Initially when I purchased the Seadoo, it suffered from water ingestion causing the crankshaft to fail, which was replaced under warranty. At the time, I had considered a suggestion from John Hill on rec.sport.jetski to send the motor out for blueprinting to Watercraft Magic or some other reputable shop. I am still considering the suggestion and possible porting (if feasible) over the winter if this would enhance performance and reliability.

At this point my only concern is the rev. limiter. At one point in time with the current intake grate and impeller, it was running a consistant 7000 rpm at sea level on ~75 degree days with 90% humidity. Will the modifications that you suggested possibly cause the motor to exceed the stock rev. limiter settings?

Thanks for the patience,

[Colin GSXL]

I read somewhere that the white motors have fairly aggressive porting already compared to the silver motors. If you add the mods Bill suggests you should turns a few more revs. I guess it may be worth either having your stock impellor tweeked or fit an aftermarket one to give you a few more mph and bring the revs back to what you are currently getting. Bill will know for sure.

[Bill O'Neal]

No your oem rev limiter is set at 7150, higher than the stock piped motor will achieve with a good matched impellor in the pump.

Sure, you could do some things that would take you past there, but without adding a pipe, what's the point. It is more time and money consuming to port the clyinders than it is to go ahead and install an exhaust system.

[Todd Adams]

Thanks again.

It is my intention to purchase the suggested modifications as soon as funds allow--shortly. However, I have a couple of other questions.

</font>

• If next season I decide to purchase the Coffman exhaust pipe, will it work "reliably" on pump gas in conjunction with the Miller TSE head? </font>
• Will the Miller TSE intake system provide a noticeable improvement in acceleration when used in conjunction with the aforementioned modifications? </font>

I am also looking at replacing the sponsons, any recommendations?
Thanks for the advice,

[Bill O'Neal]

Yes the Coffman works just fine with the Miller head with PG domes.

You probably wouldn't notice much difference with just and intake kit. You would need the reeds too.

[Todd Adams]

Re: Any ideas on 97.5 GSXL mods?

Bill,

Sorry to dredge this up from the past, just needed to ask you a question Bill. When I purchased a Miller TSE head and jetkit from you last year, I received 47 ml domes. This has been fine except on the off-hand occasion that I have used some old fuel. I was wondering, how much a new set of 49 ml domes are? And what is the recommended squish for the 49 ml domes?

Thanks,

Todd

[Bill O'Neal2]

Re: Any ideas on 97.5 GSXL mods?

$120.00, minimum squish .065

But, if you are not using a head gasket now, you can put one under the head and you will have the same cc's as if you had 49cc inserts (domes).