School me --94 w/ 5.8 Pro Boss EFI

Hey guys

I am looking at a used 94 sport nautique with the PCM 5.8 Pro Boss EFI engine. I currently have an 89 supra with a PCM 351, so I know a little about the base engine, but I don't have any experience with the EFI or the ignition system on these later engines.

I have spent some time reading CCFan threads--here is it what I think I found out.

First--This engine has a "pro-tec" ignition, which have a tendency to fail as they get older. The bad news is that parts are no longer available, the good news is that SKIDIM sells a replacement ignition system with an electronic distributor for about 500 bucks.

Sound about right? Anything else I should know about this pro tec ignition?

Second-- This engine has a TBI fuel injection. In reading about this, I didn't find much, other than several posters who noted that PCM had problems with this system and quickly replaced it with a MPI system.

Can you still get parts for this system? I didn't find anything on SKIDIM. Is it reliable? Is this system is a plus or a minus when compared to the a good old carb?

Third-- does this engine have GT40 heads? How much horsepower would it have?

Fourth-- what is the big black thing downstream from the risers. See picture below.

As I said, I am thinking about buying this boat, but right now I wish it had a plain old carb and ignition system. I want it to be reliable. Am I right in thinking that, or is this engine still a good engine?

Thanks

Jared

I have the same motor...in my 95snob. I have put about 100 hours on it. I replaced the idle control valve (IAC?). Mine runs good and strong, starts easy, no smoke, etc. I hate the way the idle starts fast then settles down. Otherwise, I like it.

As for the muffler...it is very close to the tranny shift linkage, I had to readjust mine a bit to keep the shifter from scraping/binding.



ernest

Jared:

I have the ProSki version of that engine and it runs perfectly. ALL the TBI parts are still available from either Holley, GM or Mopar. Parts from all three manufacturers are used on the TBI. However, it is basically a Holley unit.

Last I checked with PCM about two years ago, the ProTec parts are still available exclusively for TBI engines for reasons stated above.

My research tells me that the ProSki engines do NOT have the GT40 heads and the ProBoss engine DOES (contrary to what was stated above). You can check by looking for three (or is it four) vertical bars on one end of the cylinder head. The GT40 heads will have the bars.

The TBI engines start, idle and run very well. However, they burn gas at a good clip, idle a bit rich, but otherwise are excellent. Take a look at the injectors, you will find 4 large injectors that feed a 950 cfm throttle body!

Oh yes, one last comment: I believe there are a good number of the TBI engines still in use. This site lends itself to hearing the problems with these engines...that is what the site is for. However, the vast majority of boat Owners just use their boats and do not visit sites such as this one. So, my theory is that the ProTec and TBI system is not as problematic as rumored to be.

Thanks guys, this is great info. It sounds like I shouldn't be too afraid of the pro-tec/TBI combo.

First, they are probably more reliable than people think.   

Second, if there are any future pro-tec problems I should be able to get the parts from PCM.

And in an absolute worst case scenario I could do the ski-dim distributor conversion along with a new carb and be ready to go again.

Thanks again.

I hope to do a lake test on this boat later this week. Maybe next. Is there anything in particular with regard to the pro-tec and TBI that I should look at?

Jared

sjpitts wrote: I hope to do a lake test on this boat later this week. Maybe next. Is there anything in particular with regard to the pro-tec and TBI that I should look at?

Not really. Just how it runs. If the thing runs well and ski's well, go for it! As long as everything runs fine, you really can't determine that the system will magically fail while you're doing a test drive. It could fail next week or it could still be running fine 10 years from now. If you constantly are going to worry about it failing, you'll never get the chance to enjoy the boat. You'll be more worried when it's going to fail instead of having fun. Every little noise or stumble that you experience will immediately be transformed into the Pro-Tec is failing. Lighten up. It's good to know that the potential exists for this failure and what your options are when and if it does fail, but other than that, your purchase should be determined by how the boat runs now and if it fills your needs. Don't be afraid to run it fairly hard during your test drive. If it doesn't perform to your liking, then you better walk away.

I have a 94 sport with the same motor but I've been having some small issues with it and I'm wondering what my options are.

My idle seems to be high its usually around 750 so when I'm at idle in gear I'm moving pretty quick. Also I seem to have some hesitation when accelerating. Other than that the motor runs great, its very powerful and if we could clear up these issues I'd be even happier.

I'm thinking that the timing is off, is this something that I can adjust or no? We've done the timing on other boats without electronic ignition but were not sure what we can and can't do with this motor.

David: What is BG44K? Will it help an old boat like mine?

john

Thanks David.....just looking for anything easy to do to my motor. Gotta stay away from the hard stuff...unless I go over to MM's and see his brother, Keith.

john