Spirited 390-pump gas/power brake friendly 531hp

[CaptCobrajet]

Street 390 build, CP pistons with four valve reliefs.  I milled the heads to net 10.5 static compression.  BBM heads with my "standard" $400 hand port upgrade, RPM manifold with port-match and plenum mods.  Holley 830 Annular carb.  232/238 @ .050 on a 12, .580 lift hydraulic roller. Non-adjustable OEM rockers with heavy duty shafts and studs. 

The block had been a Jasper engine at some point and had a .040 tag on it.  We honed it correctly to .050, drilled up the oil galleys and did normal mods, align hone, deck, etc.  No exotics, just attention to details.  Here's what she did:

RPM            TQ           HP
3000           461        266
3500           463        308
4000           497        379
4100           502        392.7
4200           504        402.5
4300           506        415.2
4400           506        423.8
4500           504        432.3
4600           506        442.9
4700           508        454.5
4800           506        461.8
4900           505        470.5
5000           504        479.7
5100           504        489.1
5200           502        497.7
5300           495.9     499.5
5400           489.3     503
5500           484.4     507
5600           481.8     514
5700           479.5     520
5800           473.6     523
5900           467.5     525
6000           462.5     528
6100           457        531
6200           449        529
6300           439        527
6400           430.4     524
6500           423        524

It had the 5325 Morels. No short travel.  I wanted to turn it higher just to see the curve over the top, but we were running out of time, and we found peak HP there at 6100.  With the non-adj rockers and beehive springs, it never missed a beat at 6500.  I suspect it had another 200-300 clean rpm left, because it showed no signs of struggle or fuel curve issues at 6500.  I thought the very flat torque band was notable.

[Stangman]

Very impressive sounds to me your little lovin in the port work was the ticket. Nice to see these numbers on less than 400 cubic inches

[Drew Pojedinec]

Good good.... hope you don't mind, I'm going to be linking this in the future when some yahoo on another group brags about his 500+hp 390 with iron heads and an rv cam.

[bluef100fe]

That's pretty neat...

[edgarval]

What intake valve did you go with on the heads ? 2.200 or 2.150

[CaptCobrajet]

2.200

[The Magic Ratchet]

Thanks for passing that along! Looks like an easy and inexpensive to build FE!

Lou

[edgarval]

Was that on the factory crankshaft ?

[CaptCobrajet]

Yes sir.  Cast 390 cranks are tough tough.

[edgarval]

Thanks for the relieve . I'll give you a call when I get ready to buy some parts from you

[WerbyFord]

Street 390 build, CP pistons with four valve reliefs.  I milled the heads to net 10.5 static compression.  BBM heads with my "standard" $400 hand port upgrade, RPM manifold with port-match and plenum mods.  Holley 830 Annular carb.  232/238 @ .050 on a 12, .580 lift hydraulic roller. Non-adjustable OEM rockers with heavy duty shafts and studs. 

The block had been a Jasper engine at some point and had a .040 tag on it.  We honed it correctly to .050, drilled up the oil galleys and did normal mods, align hone, deck, etc.  No exotics, just attention to details.  Here's what she did:

RPM            TQ           HP
3000           461        266
3500           463        308
4000           497        379
4100           502        392.7
4200           504        402.5
4300           506        415.2
4400           506        423.8
4500           504        432.3
4600           506        442.9
4700           508        454.5
4800           506        461.8
4900           505        470.5
5000           504        479.7
5100           504        489.1
5200           502        497.7
5300           495.9     499.5
5400           489.3     503
5500           484.4     507
5600           481.8     514
5700           479.5     520
5800           473.6     523
5900           467.5     525
6000           462.5     528
6100           457        531
6200           449        529
6300           439        527
6400           430.4     524
6500           423        524

It had the 5325 Morels. No short travel.  I wanted to turn it higher just to see the curve over the top, but we were running out of time, and we found peak HP there at 6100.  With the non-adj rockers and beehive springs, it never missed a beat at 6500.  I suspect it had another 200-300 clean rpm left, because it showed no signs of struggle or fuel curve issues at 6500.  I thought the very flat torque band was notable.

Blair,
I missed this one, Chilly told me about it.
The Gonkulator is coming in a couple percent high vs the dyno.

A couple questions if you recall:
1. Was the engine driving the water pump, or electric? Overdriven (428 A/C style)  or underdriven (352 style)
2. Can you describe the exhaust?

My usual Gonkulator guess for your dyno exhaust is 2x33 headers into 3.5" collectors, maybe 18", then open exhaust.

Thanks
Werby

[CaptCobrajet]

Electric water pump.  3.5 merge collector.  Headers are 32-33 inches.