BBYSTWY

What am I missing?

I know there's a lot of threads out there and I have browsed them but haven't been able to cure my surge...I have a bored 454 8-71 blower dart heads and if you sit there for an hour and mess with the idle mixture screws it will idle amazing at 950-1000 rpm but....if you even look at lowering the idle screw AT ALL it starts surging BAD...I'm talking 550-1300 surge and the only way to make it go away is to lean it way out which ok tried that and I can get it idling at 800ish but as soon as you try to drop it in gear it dies immediately...I'm pulling my hair out with this thing and looking for options

To summarize...
460 8-71 blower dart heads....blower surge
Dual 800 holleys

have tried...
lean it out to get it to idle at 800....dies immediately when you try shifting
richen it up and the surge goes away at 950-1000 rpm but the drive sounds like its gonna explode when I try to shift
Timing is at 20 degrees with a 10 degree advance still tuning
Tried timing at 30 degrees at idle and it helped but still the above issues

I know there has to be something I'm missing

frickstyle

Mine idle pretty high, higher than I would like but it lets me shift the boat and maneuver

You could;
1. Kick up the idle and live with it (are you running bravos or a transmission type drive? I run a trans so I'm not too worried)
2. Give it some gas when you shift. I had to do this when the idle was turned down.

Someone who is more knowledgeable may have a better solution. I've also read about the Daytona sensors / ignition. That seems to be the ticket for carbed blower engines and usability around the docks.

BBYSTWY

I have a bravo which is a lot of my concern...I have read a little about the idle transfer slot next to the throttle blades and I'm wondering if that may be my issue...possibly have to pop some holes in the primary blades but before I try that I'd like to get some other opinions on the matter

I would be good with 950-1000 if I had a trans but she clunks HARD when I shift and it drops like 500 rpm and I have to be quick on the stick to keep her going

frickstyle

Gotcha. Maybe someone will chime in on the Daytona sensor.

1 MAIDEN AMERICA

How about a momentary ignition interrupt switch? They came factory on some engines.

payuppsucker

I had kicker solenoids on mine but I removed them because I didn't feel they were needed since I have transmissions. They are tied into the neutral switch so when it comes out of neutral the solenoid is activated and bumps the RPM up. They are adjustable so you can control the amount of increase.

the deep

iTrader: (8)

I believe Mild Thunder has the cure.

BBYSTWY

I should mention that sooner than later I will be going EFI so spending the money on a Daytona setup probably isn't going to happen as the EFI will control the timing I currently have.

I'm not saying that this won't fix it or discredit the suggestions for it as I really appreciate it just want to be totally up front.

I just don't understand how there are hundreds of blower motors out there hooked to bravos and they shift just fine yet mine I am having nothing but fits with and I have the same setup as the ones that run great...I just have to be over looking something

We'll see if Mild chimes in

Thanks again for suggestions everyone keep em comin!!

TomZ

iTrader: (2)

When I had mine, same thing. I would put it in gear at the low side of the surge. It wasn't a real fix but worked for the time I ran it.

Boost referencing the carburetors will go a long way toward fixing that issue.

BBYSTWY

I thought that boost referencing only came into play at higher RPM's with the power valves? Could be wrong...probably wrong hahaha