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Blueprint 383 rebuild.

Posted: Wed May 29, 2019 6:18 pm
by hdsadey
If you all followed my thread on the 408 I built, I slipped in some pics of another engine in the shop for rebuild. Blueprint 383 that nuked a couple of pistons and had a high volume pump that was chewin the distributor gear to pieces.
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It's been done for awhile but we've been waiting on the dyno to make sure the nuking doesn't happen again! Now we went .060 over (was already.040), new forged pistons, new forged rods, little bigger on the cam and roller now!, standard volume pump, 8 qt. Canton oil pan, and new Edelbrock RPM Performer manifold. Everything else was reused. Carburetor is a Summit brand Motorcraft 4100 style dual feed with mechanical secondaries. Bored and honed. Decked. Balanced. Full valve job and surfaced.

Blueprint claims 420 hp and 440 tq. We made 8 pulls on the dyno yesterday! WAY LEAN OF THE BAT! Jumped up the jets from 77/79 to 92/92. Timing at 34 degrees. The best pull was 428 hp at 5200 and 486 tq at 3500 with 90/90 jets. Still was a tad on the lean side so with 92 jets at the end 417 hp and 478 tq. Still peak torque at 3500. We could have left it at the other number but felt it was safer a little fat and slight loss of power was nominal, not to mention dyno room temps were going up, killing power! https://youtu.be/o87Uyprr9yw
AFRs are good, ready to go home now!

Re: Blueprint 383 rebuild.

Posted: Sun Jun 02, 2019 5:47 pm
by Rick McC.
It sounds like y’all some excellent work! :thumbleft:

Re: Blueprint 383 rebuild.

Posted: Mon Jun 03, 2019 6:02 am
by hdsadey
Thanks Rick we do our best!

Re: Blueprint 383 rebuild.

Posted: Mon Jun 03, 2019 7:25 am
by keys2pines
Nice! hopefully won't need your services, but you'd be top of my list if anything goes wrong on my bottom end.

Re: Blueprint 383 rebuild.

Posted: Mon Jun 03, 2019 8:07 am
by flcracker9
I had the same issue with a Blueprint 383 we purchased (used). The #7 piston had a broken ring land when we tore it apart. I replaced the piston, but honed all 8 cylinders and installed all new rings and bearings (crank and rods), reassembled, set the timing at 34 degrees total, and it's been running in a DD airboat for 2 years now. It came with Keith Black hypereutectic pistons in it, which I'm not real fond of.

Re: Blueprint 383 rebuild.

Posted: Mon Jun 03, 2019 6:07 pm
by hdsadey
Hopefully not but if you do give us a holler, we'll fix you up!

Yeah this one had the KB's too! Not what we would call a severe duty piston like a gearbox boat should have. Of course it did not help being WAY LEAN! If the ratios would have been correct probably wouldn't have melted down. Forged just adds a layer of protection.