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FE Power Forums => FE Technical Forum => Topic started by: 70bosscat on April 24, 2019, 07:24:12 PM

Title: Blair's 531 hp 390 with tweaks
Post by: 70bosscat on April 24, 2019, 07:24:12 PM

Say you were to duplicate this build with the only changes being 50 more cubes, 15 more degrees duration @.050 and .060 more lift. What rpm do you think it would make peak power and torque and how much would it be?

Title: Re: Blair's 531 hp 390 with tweaks
Post by: chilly460 on April 24, 2019, 09:14:01 PM

Don’t have build in front of me, but it’d likely peak around 400-500rpm higher with that much more cam even with the added cubes.  Caveat being that the induction wasn’t a restriction.

Title: Re: Blair's 531 hp 390 with tweaks
Post by: WerbyFord on April 24, 2019, 11:27:24 PM

I don't have a 531hp Blair 390 either but I found this dyno from Blair:
Torq 504 at 4000
Powr 517 at 6000

Here is what the Gonkulator got (with a water pump)
Torq 505 at 4300
Powr 506 at 5800

Now add 15 degrees & .060" to the cam so 240 248 .570 .570 up to 255 263 .630 .630
Torq 501 at 4600   -4
Powr 532 at 6100 +26

Now 4.25 stroker to add 50cid
Torq 560 at 4500 +59
Powr 541 at 5900  +9

That would be my guess.
This build had iron 428cj heads so probably running out of air.

Title: Re: Blair's 531 hp 390 with tweaks
Post by: chilly460 on April 25, 2019, 08:07:58 AM

Here it is Werby

http://fepower.net/simplemachinesforum/index.php?topic=4575.0

There was a TFS headed 462ci that Larry posted awhile back, 246* hydraulic roller peaked at 6200rpm, Blair posted an Edelbrock headed 471ci(?) that had 5800rpm peak with a 248* hydro roller.