Stumbling after 4-5k rpms

ok, so you are saying that my timing is not the problem. The pro-tec is not the problem. Did I read into that correct?

Im not getting backfires. I can hit it out of the hole from 0-39 mph, not hesitation, nothing. Sling shots out. But it seems to have a hard time "finding" itself, but then hits on all and proceeds to 5k with no issue.

I havent checked my antisiphon valve yet. Not sure....   

Its not a big deal to me. It runs fine, i usually do not run that fast anyways. It would nice to nail this down. It was definately better yesterday. Who knows, maybe its just crappy gas from sitting in the tank for 13+ months. It was full and stabil in it through the layup, but....

I need two boats, one to tinker with and one with EFI!

Thanks. I know I have to re-time it. I couldnt yesterday because it was too bright out. I couldnt see the light, nor had anyone to shield the sun so I could at least see the light.

The nautique dealer thought that the radio noise at the upper might be whats causing it. (only reason i mentioned it) Like I said, I will try and get it timed again.   I have the autolite 764 in there gapped at .045. Just as my manual (and skidim) recommends.

I guess you cant read. I can get to 5k and the pro tec reduces the power you idiot. Its the pro tec pack that is going bad. 5k is the limit on this boat per Nautique. (called the local dealer).   So if want more speed or higher RPMs past 5k, i need to switch out to the pro tec.

My issue before was that it never got to 5k. now it does with slight hesitation at around 39 mph @4500 rpm. Right between 4500 and 5k she has trouble finding the timing it sounds like to me, then hits it and clean up to 5k with no issue.   The pro tec pack probably is beginning to break down and noise is happening. (i think the dealer said radio frequency) the coil packs cant take the load.

So before you lame blast me with your childish smiley faces and broken english, do me a favor and find the tech manual for pro tec and read up on it. Because you do not know what you are talking about.    Everything else beside pro tec I think you have some great knowledge, bad presentation.     its like every morning someone pissed in your coffee and you started typing in the forums

So I just had it out again. Checked the gaps on the plugs to .045 and took off each spark plug boot at the protech box and of course the spark plugs and put some dielectric grease in each. I pulled on boot off the box and it was a little rough. So Im guessing that was the boot end possibly failing and grease helps it.   I can get to 5k pretty easy now, but I still have more throttle left, just that the protech wont let me go past there!

She did surge around just after 4500, but I think its timing. I tried to retime but it was too bright out trying to see the light was next to impossible. I suppose if I retime one more time, I think it will be good. If not, the protec is shot at the upper end.

All through the rest of the RPMs, its great. out of the hole floored she rockets out of the water, no issue. Idles great..(little high because timing is not quite right).

I'll fix the timing another day...   I usually do not run constant at 4500k anyways, maybe when I barefoot, but my speedos are off right, need to recalibrate those.   Since its not pinging, I think im ok for now. Need to get rid of my old fuel. Another half tank to go and refill with 89.

Picture of Kal-i-for-nia dry docks in discovery bay

tommer12 wrote: TRBenj wrote: Nope, guess again. We upgraded to GT40 heads on our 255 hp '92 with Protec and it ran up to 4700-4800 without issue. The rev limiter on the Protec shouldnt kick in until 5k. Bore and stroke are obviously the same between the 2 motors as theyre both 351w's. Compression should be very close, as the GT40 and standard E7 heads have very similar sized combustion chambers. The P heads have smaller chambers and will bump you up to 9.0-9.5:1. I have seen no evidence to support that the cam was upgraded on the Proboss motors, though. Thats awesome to know! I will check it out farther now with retiming it and possibly gapping the plugs. Do you think the I should gap the plugs to .045 as skidims recommends with the proboss?    (aka GT40-P heads I run now from stock?) I really appreciate your feedback!

So when you said "issue" up around 4700-4800... was this its limit?

You can, and it wont hurt- but it wont solve your issue either.

Nope, guess again. We upgraded to GT40 heads on our 255 hp '92 with Protec and it ran up to 4700-4800 without issue. The rev limiter on the Protec shouldnt kick in until 5k.

Bore and stroke are obviously the same between the 2 motors as theyre both 351w's. Compression should be very close, as the GT40 and standard E7 heads have very similar sized combustion chambers. The P heads have smaller chambers and will bump you up to 9.0-9.5:1. I have seen no evidence to support that the cam was upgraded on the Proboss motors, though.

tommer12 wrote:    He said to try some diaelectric grease on each plug wire boot to make sure its connecting solid and try again.. otherwise... its time to replace the protech. Wait for it.... wait for it..... "I told you to get rid of the POS protech system!"

you need to stop talking to this DA

better advice would have been to clean all the grounds on all the engine wiring. Setting the base timing correctly so the computer feeds the correct information to the module to fire the coil properly.

But what the hell did *************** listen regarding the fuel pump NNNOOOOOOO..... so I really don't give a fly F anymore if you fix it or not I just know I done waisting MY TIME ON YOUR SECOND GUESS DUMB .... just my .02

I dropped a call to my local CC dealer. The guy there said it is possible the computer getting mixed readings at higher RPM and putting the engine into power reduction mode. The mixed readings are from radio frequency waves from the plugs arhing (I think that is what he said). He said its pretty hard to diagnose the issues, but after 3200 rpms and power drops or surges like that, the computer could be causing it to this. He said to try some diaelectric grease on each plug wire boot to make sure its connecting solid and try again.. otherwise... its time to replace the protech.


Wait for it.... wait for it..... "I told you to get rid of the POS protech system!"

8122pbrainard wrote: It's a good thing I haven't ever mentioned the timing light I have to Chris. No advance feature!!! The one before this one was a simple zenon light!!

Pete There's one at the shop that I bet is older than you, looks like a small light bulb with leads and aligator clips. BTW why the hell would you have a good timing light your still d*cking around with points, but hey at least you don't loose any judges points

It's a good thing I haven't ever mentioned the timing light I have to Chris. No advance feature!!! The one before this one was a simple zenon light!!

if idle isn't steady or the timing you have other issues that are not fuel related.

So for the umptenth time, set base timing at 10 BTDC knock sensor wire connected, setting the interruptor's base timing, disconnect knock sensor verify timing is steady, verify timing at 3600 rpm

but get a real timing light so that the timing can be set properly.

Its a love/hate relationship. I see it already.

From being on the trailer, I do not have it gear at 700rpms. It was 700 in neutral. So this could be why also.      The knock sensor is a wire with a nut on it. You have take the nut off, remove the wire. So its off.

Should I be in the water, in gear at 700 RPM and time then? I clearly have a white line I put at 18 BTDC. So my light is hitting the point at that line. Unless my light is screwed.

I don't expect lip, I give it back very harshly at times,

so either your not too good at reading a timing light or your's isn't very good and you need the correct style light. The timing will not vary, so the 16-18 something is wrong, your technique, timing light, or the protec module. It should be steady at 18 BTDC knock sensor disconnected and this is only for verification not adjusting. So if it's not steady at 700 rpm, did you even look at that after the knock sensor was unpluged? and at a steady 18 BTDC there isn't a range for this then it's screwed up and not set correctly or the module is going out.