Steve, what are you running for AFR's? I know some guys run in the 10's and go with more timing. I like to run mid 11's and keep timing @ 30* max.

Bananarama , sorry not max load PEAK TQ (off dyno sheet ) At peak TQ/VE, you will need the least amount of timing because the charge burns fast as I`m sure you know.


I was playing with idle today this is where I ended up @16* 875-925 rpm



https://www.youtube.com/watch?v=hDqAawtfF0g&feature=youtu.be
I know nice exhaust but the a-hole powdercoating them blew another deadline today.

Bawana, at WOT? If so, then I don't really know yet. I've been working more on idle and cruise and when that is right, I'll move on up above 1/2 throttle to WOT.

I've been working on my carbs for some time now and had things going quite well at idle, but cruise was still a tad rich. Idle AFR was ~13, 2500 RPM was 12.0 with 3.5" Hg and 3000 RPM vacuum dropped to 0" Hg and AFR was high 9s / low 10s with a 3.5 PV, Ø0.081" PVCR as delivered and 89 primary jets. I had dropped the primary jets to 84 and installed 2.5 PVs in primaries (sec PVs were blocked as soon as I started, first thing I did and sec jets were already 94 so I left those alone) plus I have installed brass set screws in the PVCR and reduced the hole to Ø0.073", but then my MSD 6M died, so today with the DS box was the first fire on the garden hose since making the carb changes. Surprisingly, the AFRs seem to be a tad lean at idle, but surging and shouldn't, I think I may need to calibrate my O2 sensor again. Taking to Lake Pleasant tomorrow along with my laptop to play with timing maps on the water and log some data.

Steve

Wow Dan, nice idle! Is it me or is your top pulley large...maybe the video makes it seem that way. I have 49 lower and 52 upper and on the video yours looks considerably larger (and polished!) than mine...maybe your lower pulley is large too...what's your UD %? Regardless, nice idle AFR and RPM with a tiny 50RPM lazy surge. If I take my AFR that high, the engine smooths out but idles just above 1000 RPM, no good for shifting my XR drive.

Summer is almost there in the Midwest!

Steve

Steve, you boost referenced? I had some similar issues with a fuel dump when the PV opened. Was doing the same things you are to correct it. The new Quickfuels are boost referenced, I`ll see what happens this year. I ended up with 91 secondaries.
I was hoping for a little surge but no matter what I do I can`t get it to give me a little blower surge.
Yes my pulley are huge.. came that way. 62/63

So you can`t lean out the carbs and turn down the idle?
You don`t wanna run a tad more timing at WOT? Might be leaving a little on the table and them EGT`s could be getting up there. 525sc and 600sc had 35/33 max advance ...and you got light boat

Dan, thats a nice little setup ya got going there.; sure beats the hell out of climbing in and out of the boat a million times. I asked about the load thing because in my boat depending on what props I run, and if I am on 2 or 3 motors, that can change the load thats on my motors. Before you ask... I have on a couple of occasions had to run on two motors, when something happened to one of the three. two different poker runs & a few other times. When all three are running its like having big power in a tiny boat... then on two its like being over prop'd 3 pitches or more.

Thats the beauty of the Daytona box coupled with a map sensor and 3D map .. more load = less timing. Lake Michigan I can be cruising at 4000 @ 1 psi on a nice day with some light chop and other days you`re dragging an anchor with friends , full tanks , cooler full of Moonshine, 7 suitcase full of clothes the girls packed, ammo, etc and draggin tabs @ 4psi.
Btw where in Wisconsin do you boat? We need to hook up this summer if I`m not in jail over my interior and exhaust.

Steve, yes I was asking about your AFR's at around 3" to up into your boost. Sounds like you have you idle & mid right there, with some water testing ahead for your boosted to WOT. I know it depends on what motor guy you talk too, some like fat AFR's (9's &10's) and go with big timing (35*/36*) and others go with AFR's 11's to 12's with timing as low as 26*. So far I have been lucky with mid 11's with 30* locked, but ya know how it go's ... can't leave well enough alone...lol

Yes, during the first tear down and blueprinting I boost referenced the primaries only along with 3.5 PVs. Prior to this, 6.5 pri PV / 8.5 sec PV and not manifold referenced, 89/94 jets, 71 IAB, 37 MAB, 41 IFRs, and TSRs didn't match on both carbs...one had the brass bushings still in it (all 4) and were around .085" I think, the other carb had them removed and the holes left behind were .110.

BTW - Merc 800SC was 28 deg BTDC max and I'm north of 900 w/14-71 and running 91 octane pump gas. I don't know what the static compression is either, but when it was at 36º locked timing, warm or cold, turned over without any complaints, so presume it's relatively low. I probably will add a few degrees in the upper RPM table just because I can now with this super cool Daytona Sensors BOX! Actually, sitting here watching the Xfinity race creating additional timing tables that I can easily upload tomorrow...stay tuned!

Steve

Dan, I do most of my boating on lake Winnebago, your group should come up. The four horseman poker run is June 12th & 13th. Alot of fun peeps will be there. I also want to do a Chicago run this summer, so if nothing else, could hookup with you guys then. PS... what exhaust did you get??