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8.3l Whipple vs. 10-71

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Old 02-12-2022 | 10:05 PM
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Probably too small to run an 8.3l Whipple.


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Old 02-12-2022 | 10:16 PM
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Dan: just wondering what Rotors your roots blowers were using, 60 Degrees or 120 Degrees? not that it maters much at this point just curious.
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Old 02-12-2022 | 10:21 PM
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Still waiting for pics of whipple manifolds modified for better distribution, especiakly for carb apps. Anybody have pics or sources ?
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Old 02-13-2022 | 07:31 AM
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thats a very big 7 cylinder?
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Old 02-13-2022 | 08:23 AM
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Originally Posted by ICDEDPPL
Probably too small to run an 8.3l Whipple.

I see you have my boat's new engine.
I'm running these turboes.

https://i.ytimg.com/vi/qTeRPH5_vlk/maxresdefault.jpg
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Old 02-13-2022 | 09:20 AM
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Originally Posted by ICDEDPPL
When did a 9.0L 548ci become "small cubic inches"?One day I`ll grow up and get myself a real engine with some cubic inches I guess.
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.
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Old 02-13-2022 | 12:59 PM
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I know, it`s all good lol.
The blower is a little big but like my wife says it doesn`t hurt.
Let`s see how that tunnel ram with port injection works out .
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Old 02-19-2022 | 01:36 PM
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Originally Posted by Panther
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.
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.
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Old 02-19-2022 | 07:40 PM
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Originally Posted by delsol
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.
The 3.8's are super efficient and some may be disapponted when they wind them up, because they are so quiet. You really can't hear them at all like the ones before, which is a good thing because they aren't producing a lot of heat. My 525 efi's whith the 3.8's dyno'd 830 hp @ 7.8 lbs of boost and can go to 11lbs if wanted. Only downfall for me is my factory cooling on the 525's is really good for up to 900 hp, so i'll never fully use all the boost I have. This is just a reference for the 3.8 whipple question.
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Old 02-19-2022 | 08:12 PM
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Thanks for real world feedback
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