Dyno BSFC question
 

Engine with quad rotor EFI that makes 1000 hp at 6000 rpm.
Brake specfic on the dyno was .603 at 4400 rpm and .650 at 5000 rpm and .701 at 6000 rpm at peak HP. Really fat engine. Question is can a very rich engine make power on the dyno yet be a real turd in a boat. The owner has been battling a boat that is slower than same hull setups. One engine builder told me horsepower is horsepower. I am wondering if the rich condition will not allow the engine get past the torque curve.

This is a more accurate picture

What did Bill think guys ? Isnt he a top notch builder you guys both know ? good luck , been reading the ongoing threads, good luck kirk

Running that rich is hurting you. I would run the BSFC at .50-.55. . .500 at the low end of the pull and .550 at the top end. Your giving up a ton of horsepower and yes it will run like a turd in the boat. Hope the rings are still in it! :eek:

Kirk this "motor" in question,it had high bsfc numbers before too but the afr's were correct?-was this the dyno sheet the owner got with it-
Smitty

Its not in question to me.

Yes its fat, but Gary Taylor has run this set up in his Howard Bullet for years with no issue. He builds the engine, rigs the boat and has done 130 MPH in a single. There is nobody on this board or industry that can claim that type of success in a single V. He built this engine and I trust him more than anyone. Is is the only engine he builds.

I might tune it in the boat, but it is not the reason why I am down 10 - 15 MPH. The torque and horsepower are there.

If I get ambitious and want to fine tune, its very easy and I have the program, laptop and cable. I have learned to modify the tables with a mutliper and have an O2 meter.
Piece of cake on an EFI.

I have bigger issues unfortunately. Drive? Hull??

I need Brads Skater with 6 drives. I can sell the 525's and buy another TPI engine! Problem solved. :evilb:

Bill (Ateco) and I are both wondering if the rich engine would hold it back in real world application versus a dyno pull where an engine brake matches the power. The obvious fix is to lean it down and install it back in the boat. But we are trying to figure out why Kirks boat would not run faster after such a great dyno pull. I can not help but think the fat engine won't run in a boat under a heavy load even though it makes 1000+ hp on a dyno.

I am also thinking a stepped hull like a Gary's Howard would allow the boat to get past the rich setup. I think I also heard Gary does not run his personal engine this rich.

IMO I have looked at the pictures Kirk has posted and I think the problem is with the hull/drive setup. I had a running rich problem when I put new motors in my boat and after it was dialed in running the boat, I saw no increase in top speed, just better running/idle and no more black transom.

I think that hull needs to go back to Florida and let the guys who built it take a look at it.

All my point is .......why leave power on the table. Yes, the power is very good , but can be better. And your EXTREMELY safe . It looks like a great combo!:cool-smiley-027:

.......why leave power on the table. ??? absolutely plus chance washin the cylinders down .....& losin the rings .... We were at .500 - .550 and made max hp and on the water plugs are coffee brown :cool-smiley-011: good luck KIRK call me need some 8 mm # 48 pulleys