TooLateVTEC

iTrader: (1)

Agreed, that or there was a flame arrestor on it that was too small.

MILD THUNDER

iTrader: (3)

Mike and I both said we would have went with a dominator had it been our build. That was one of the reasons we thought it would have been power limited.

I really had nothing to do with this build myself. Mike is a close friend so anything he's messing with, I pretty much stick my nose in.

KAAMA

iTrader: (1)

Very impressive....especially with those chit GM cast iron junk heads and only one carb---nice work guys!

Bawana

Very nice job... What is the static compression? I also noticed that the AFR was about where I like them (11.7) but I thought Mike like to see 10's?? I m sure that will be adjusted in the boat, but would love to have see what the numbers would be at with AFR in the 10's.

mike tkach

iTrader: (3)

no need to run the a/f ratio in the 10s at this hp level.it is leaving the dyno with a safe tune that will no doubt be ritcher in the 5500 lb boat.it will have the a/f ratio checked on the madin voige.yes,imo the carb&flame arrester are to small but it is what he had.the heads had the valve job and bowl blending done on a neuen cnc head machine and i believe that helped a lot with the numbers.when it is in the owners budget it will get a set of afr305s and a much larger carb.it was run on bp 93.

Full Force

iTrader: (5)

It's amazing how much air carbs will flow under boost at times.... I really wish my buddy Lake Effect would dyno his engines with prochargers... 353 formula at 107, gotta be making 800 hp...

MILD THUNDER

iTrader: (3)

I believe they came in around 8.7:1

From what Ive seen on the dyno with various roots blower engines, air fuel ratio doesnt kill power like you think it would. Icdedppl's blown 540s with 10-71's made there best power at 11.5. On some, the difference from 11.0 to 12.0, was like 10hp, which on a 900hp means almost nothing. At least in a boat.

Leaning them down, also doesnt equate to more power. When dynoing my engines, the baseline jetting was way too lean. At 6000RPM, and 12.9 AFR, HP was 788. Jetting it up, 12.2AFR, picked up 5HP, to 793HP at 6000. I picked up about 5hp, and 6ftlbs of torque with the larger jets.

In the boat, I've ran mine from low 12's at wot, high 11's at wot, and low 11's at wot. Boat runs the fastest with them in the low 11's. I think the little extra fuel seems to keep things cooler. I cracked the porcelin on a plug with 12.5 AFR. Cruising, my AFR is around 12.0 currently, around 12.5ish at idle, and low 11's at wot. The transom is always clean.

I think the key is finding a setup that work for each engine. Maybe it stays together at 12.0 AFR wot, with retarding the timing, or maybe it makes more power at 11.3, without retarding the timing. I run 34* total on my engines. I'd rather have a little more fuel and a little more timing at wot, vs a little less fuel and less timing, my gut tells me the exhaust valves will like it better that way.

MILD THUNDER

iTrader: (3)

This carb really isnt "under boost" so to speak. Its still a draw thru. Now, on a procharger setup, heck ya. You can make 1200+hp with a single 4150 carb.

On this particular engine, while it made very good power, I would have like to seen it get pulled with a 1050 or 1150 dominator. I'd be willing to bet a case of beer the numbers would have picked up a little.

Payton

Very impressive guys! Congrats

Full Force

iTrader: (5)

Gotcha I thought it was the same either way, I am not super educated on blowers haha I learn more all the time