trc2

I have a 2000 29 scarab with twin small blocks in it and I put new heads on with stainless intake valves and inconal exhaust valves same size heads as stock so Idid not change anything there and then I add 5 psi pro chargers the computers have been redone new fuel pumps checked timing and fuel pressure is all in the specs but @ 4000 to 4200 rpm the boat falls on its face if you push the throttles just a little pasted the 4200 mark you feel the boat fall forward everything checks out to be all in order fuel air boost spark but if you hold it it will slowly climb in rpms but only to about 4500 it runs its a$$ off up to that point of 4200 rpms O and its not the props because we even put smaller props on and it does the same thing runs out if you push the sticks all the way forward it all most seems like I need more fuel at WOT any help PLEASE

lake speed

do you have a fuel psi gauge? it sounds like it is running out of fuel. pull a plug and see if is been running lean. i wouldnt keep trying to run it that way until i was sure what the problem was. what size injectors are you running?

DMOORE

No doubt, don't run a blower motor lean. They will gernade in no time at all. Like was said, check fuel press first, then go from there.



Darrell.

trc2

fuel pressure is not it we are running 57 psi at WOT the boat has about 10 hours on it since the pro chagers where put on there has been no sign of the motor running lean and the injectors are stock mer injectors these are the mer 350 mag mpi 300 H/P motors I'm trying to see if anyone else has had this problem and how they fixed it My only guest would be it needs bigger injectors because of volume of fuel the injectors wont produce enough fuel what do you guys think but if this is the case and they need to be bigger why wouldnt pro charger supply them in the kit if they are needed or say you need to up grade you injectors this has realy suck this year I have lost most of this season of boating

ZXXX Donzi

Who reprogrammed your ECU? They should know exactly what is happening. That is the person that wrote the cal. He should know how the boost tables (if you have a MEFI-3 and up. And are using a 2 Bar MAP sensor), pulse width, and timing will interact with your boost reference levels etc.

If it is boost referencing correctly, your plugs are right and you don't have any ignition problems, I doubt that there is much the rest of us can tell you. I do know that a stock kit does work. If you think that you are running out of injector, you can always try adding a few PSI of fuel pressure. That will tell you something. Don't jack it up to 75-80PSI or anything or the injectors will not open. Better do the trial and error on the rich side than the lean side.

Plane Silly

I think those injectors are 50lbs ers. I ran that same combo in my Crownline. ASM did my recal for the 350 and then again when I upped it to 383. I didn't have any problems running those injectors even with the stock fuel pump. I monitored things with an air/fuel meter. I suspect your computer tune.

trc2

Mark at precision marine did the computers and has done several of them and know one else has had this problem so we are at a lost right now on what else to try its only when you push the throttles past 4100 to 4200 rpms that the boat falls forward and it acts like it is running out of fuel
B reak
O ut
A nother
T en thousand
in my case

ZXXX Donzi

Ouch. You do have a head scratcher then.

Hang in there. In the long run you will love the new hp

Strip Poker 388

iTrader: (6)

most of the bbc kits ive seen they said they were running around 70 at wfo,


does the fuel press change at 4200+?

trc2

In the pro charger kits it says the fuel pressure should be around 57 psi max