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ghittner 10-06-2006 09:42 PM

Re: Idle question
 
Ran a very similar setup to yours last year and yes, that was normal for me. The idle drop is hard to get out but as stated earlier, is quite normal for that cam. If you are getting a bang at shift it won't hurt, mine has done it for years and years. It is part of the equation when you build over stock and especially with any kind of cam. I'm getting a 600-800 RPM drop now that I've added a blower, that's even harder to deal with. PS- don't take timing away. Add it if you can, it will help a bit.

JohnSchiavarelli 10-07-2006 03:06 PM

Re: Idle question
 
Thanks for the advice.. Just got done, tuning yet again..
double checked the timing. it was closer to 38.. I never did check it last week after I added the 6+ box.. Got it at 34 now.
Also, got the carb as best as I can get it.. idle is 650 in gear, 950-1000 out.. Sounds like this is normal, and the best it will get.

RLW, why do you not use the start retard? Seems to me like a win-win situation??? I have had it turned on for a week now, no issues with it.. Curious

Thanks again

John

RLW 10-07-2006 03:58 PM

Re: Idle question
 
John,
I have experimented with the start retard and without it. It doesn't seem to make any difference, most of the time. There has been a couple times where I would get that slow "over the hump" like start but, it has been far and few between. I actually played with it today. I just got done installing a new harmonic damper and wanted to run it in the driveway before tomorrows boating excursion. I initially started with the -20 degree feature.
I started the engine about four times using it. It started fine and idled fine.
I deactivated the start retard and it also started and idled fine.
I always thought the Start Retard was to provide easier starting of high compression engines.
Russ

KAAMA 10-07-2006 10:10 PM

Re: Idle question
 

Originally Posted by JohnSchiavarelli
Current Setup: 540 ci Naturally aspired 9.2:1 comp.. Aluminum Heads.
Cam duration is 233in 237ex lift is 600in and 580ex. 112ls.
850 Sea Daemon. The ignition timing is locked out at 34*

Boat runs great..
The boat idles at 900 to 950, and in gear drops to 600-650.
Is this normal?

Thoughts?? Other options? John

John just FYI, I run a very similar cam duration (@.050") numbers just like you although @.050" duration numbers don't tell you everything about a cam. These cams are used in my 565cid engines, 9.5 cr, aluminun 315cc heads, HP950 Holley w/4 corner idling, Crane HI-6M ignition box, MSD crank trigger, Autolite AR3934 spark plugs, 34* locked in timing and the engines will idle down as low as 550rpm in neutral if I want....but I usually keep them around 700rpm or so. Dropping them in gear is a nice, easy event at that RPM and will see 500rpm in gear if I choose. Cranking compression will show about 185-190 lbs on the gauge. I use a jig that retards the timing down from 34* to about 16* or so when starters are cranking. I have run at idle speeds in "no wake" zones on several occasions for over an hour at a time without any load-up---no load-up ever!


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