8.3l Whipple vs. 10-71
#85
Registered

Joined: Jan 2006
Posts: 3,601
Likes: 1,169
From: taxachusetts
I see you have my boat's new engine.
I'm running these turboes.
https://i.ytimg.com/vi/qTeRPH5_vlk/maxresdefault.jpg
I'm running these turboes.

https://i.ytimg.com/vi/qTeRPH5_vlk/maxresdefault.jpg
#86
I didn't mean you didnt have a good engine. Just that the big blower on a lower boost setup can sometimes cause more harm then good. Or, if you want to do it, you have to compensate somehow for turning it slow with running port injection for instance or a little richer AFR to help the lean cylinders because of going through the hat. Its sort of like putting a huge carburetor on top of a small engine and there's no signal. The same issues can happen on a 14-71 on a 548 with low boost. For instance, I'm building some 540s right now and I opted for the 3.8 because were going to make 950hp. If I wanted to make 1200-1300, I would have upsized the blower.Just trying to help and give some suggestions.
Last edited by Panther; 02-15-2022 at 08:47 AM.
#88
Registered

Joined: Sep 2001
Posts: 1,542
Likes: 55
From: Kingsville----lake erie
I didn't mean you didnt have a good engine. Just that the big blower on a lower boost setup can sometimes cause more harm then good. Or, if you want to do it, you have to compensate somehow for turning it slow with running port injection for instance or a little richer AFR to help the lean cylinders because of going through the hat. Its sort of like putting a huge carburetor on top of a small engine and there's no signal. The same issues can happen on a 14-71 on a 548 with low boost. For instance, I'm building some 540s right now and I opted for the 3.8 because were going to make 950hp. If I wanted to make 1200-1300, I would have upsized the blower.Just trying to help and give some suggestions.
It would be interesting to see the dyno results of a 565 with a 3.8 vs a 4.5L up from 900 to 1100 hp, with each individual cylinder monitored to better understand the fuel/ air distribution.
#89
How do the 3.8's compare to the 4.0 and 4.5L Whipples? I'm hearing more guys using the 3.8 for a 900-1100 hp build -- are the 3.8's that efficient they will support 1100hp with 91 octane? I'm assuming a MOAC intercooler on these builds...
It would be interesting to see the dyno results of a 565 with a 3.8 vs a 4.5L up from 900 to 1100 hp, with each individual cylinder monitored to better understand the fuel/ air distribution.
It would be interesting to see the dyno results of a 565 with a 3.8 vs a 4.5L up from 900 to 1100 hp, with each individual cylinder monitored to better understand the fuel/ air distribution.





