articfriends

iTrader: (1)

I would NEVER tune to achieve a bsfc number, the motor needs what it wants. I bought a daytona 8 pack 02 sensor for my dyno, the way to go. I have seen waaaay high egts on blower motors too, adding fuel made them go even higher. Afrs, ground strap readings, egts and bsfc in that order to see how efficient a combo is.
Now, back to bsfcs, IF a guy built the same combo over and over again, ci, cam, heads, you will see bsfcs in a certain range but again, would never tune for them.
Afrs in 10s are generally rich to point of washing cylinders and totally unnecessary on NA motors, fwiw, smitty

articfriends

iTrader: (1)

I have also been on other peoples dynos where they had older 02 tailpipe afr gauges that weren't real accurate/didn't match/varied all over the place in back to back pulls and they sorta got ignored, hence the modern, quality 8 pack 02 system I invested in for my dyno

bck

Well, let's try this. Maybe he achieved the correct results. What numbers do you guys tend to want to see for AFR and EGT? What numbers do you tend to see for bsfc ? Pretty basic motor, 1050 Dom, hyd roller, afr head, 9.5, 700hp @ 5800

bck

MT, you asked a few questions earlier- I don't know if I posted them before but we check different timing settings. Stopped making power at 34 so that's where it's at. I've been using the standard NA curve in both the Crane box and now the Daytona box as well. I'll agree with you guys that he is probably not using the best technique but on the other hand he has been doing this a long time and I'd hope has decent skills and knowledge base

articfriends

iTrader: (1)

About .480 bsfc is normal for a na engine, at least from what i have seen on my dyno, 12.2 to 12.8 afr makes about same amnt of hp so i final tune on water towards lower 12s, at 13 its marginally lean, when you sart getting into 11.8 to 11.5 or so na they sart getting piggish, at 11.0 and richer they start getting real piggish and losing hp, in the 10s they start chugging and washing rings, turning transoms black, losing real hp, at least from what i have seen, Smitty

bck

Where do you start getting uncomfortable with exhaust temps? Depending on where you look in the powerband it's down sometimes as much as 10hp and ft lbs after richening it up. Further, how much fatter should it be because we ran it on a 90 degree day to keep it safe on a 72 degree day?

bck

Full Force, I figured with no interaction with you for several months I'd check and see if you grew up a bit. Guess not, so I'll take the low road with you for a post. The engines made over 700hp back in Feb and made over 700 again this week.They made more torque than yours made horsepower even with your blog cabin build threads and two failures due to your incompetence before they ran. What will mine make with accessories? Whatever they make, I don't care. If you actually read the many dyno sheets I took the trouble to post instead of just rambling on like a child you'd see where some of your missing hp is. I'm happy with the parts that I approved of and purchased like an adult and the power results I'm seeing. I don't need to have a boat as an extension to look down and see my p*nis so I'm not losing sleep over when or if I get the engines in. I also don't need you to tell me if I'm happy with my engines or the people that helped build them. I'm going to sum up every post you make very nicely " I don't like Bob or Phil, I really can build an engine, it's someone else's fault, my cigarette is better than whatever you have and I run my boat harder than everyone else". Now you can go back to being blocked and maybe I'll see if you have anything intelligent to say in another 6 mos or so. My apologies to everyone else for derailing my own thread, but I have dealt with so many disappointing people in the marine industry that my tolerance level for any form of bs is nil even on a forum.

SB

iTrader: (1)

BSFC's with good modern heads like yours and that compression, usually .440's-.460's.
EGT: haven't seen those in a long time.
A/F ratio with known good wideband 12.0-12.5 for good safe tune (this is for WOT)
GPS: As fast as you can get it. LOL. Back to serious, this I use as a tuning tool too. Along with plugs and transom color.

bck

Except for some .5xx below 3500 and a brief dip to .396 for 200 rpm the bsfc was always in the 4s. The average bsfc for the pull was .462 so not bad. The highest egt was 1480 on one cylinder at the very end of the run. He really had a thing about not wanting egt above 1450 ish. 1 and 8 were always the hottest and those were the plugs he checked a few times.

bck

Hopefully this comes out ok. I folded them up to get all the fuel info back to back then just took a pic.