I recently installed delta heads with a new gutted stock exhaust on my pro drive 36 on 18x54 sbx. Cranked it up last night at the house and noticed it spitting the occasional blue flame out the exhaust. Is this normal with a gutted exhaust? I removed all baffles and cut the perforated end off the outlet pipe inside the can and welded back up. I'm running a gator tail stock exhaust on a pro drive if that matters, but wouldn't think it does. Haven't had it on the water yet, hope to try it tomorrow. Seems to run fine other than the blue flames at night and occasional backfire. I'm guessing I should have left the perforated pipe on the outlet in place, just wanted to make sure flames weren't indicating something else going on. Stock motor needed some help with pushing loads in that heavy boat.

Was it in a dark or lit area, perfectly normal to see blue flames with AM exhaust and headwork at night. You'll see it just with a better flowing exhaust.

It was dark, I'll try to upload a video if I can get it to go through. Good to hear it should be normal though!

Sent from my SAMSUNG-SM-G891A using Tapatalk

https://youtu.be/cMhC-rj7d6Q
Should work, couldn't get it to upload through tapatalk.

Sent from my SAMSUNG-SM-G891A using Tapatalk

Roll with it, they all do that.

Sent from my SAMSUNG-SM-G890A using Tapatalk

Those are short you'll be fine. I used to have 3-4" blue flames out my old duals constantly. Looks good at night! The only problem is, you would be able to enjoy the show since there behind ya.

the holes are hitting!!!

AFTERBURNERS!!! Haha thanks for the input, maybe i won't be hassled too much about it on public land.

On another note, about what is the average compression with delta heads and what octane is everyone running? Pretty sure mine was right at 160 stock, and was 172 with Deltas heads. I was expecting more around 180-185 but the deshrouding may have brought it back down. Either way I'm excited to run it, and hope to be getting a Lectron kit and cam from them before long, probably one at a time as budget allows.

I know when I went from a stock 35.5mm to a 42mm keihin on my 400ex after exhaust, cam and 11:1 piston it made a huge difference, much more than I was expecting. Hopefully the lectron will be a similar shot for a prodrive.

After a run i would pull plugs and check for a lean condition... just in case