Thread: 390 Turned 445 Stroked Mudder Project

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I feel kind of silly putting together a combo, when Barry could just pull parts off the shelf and make more power or a better combo. He's the FE expert here and could make me look like a dunderhead.

Irregardless of that, I do like putting parts together on the DynoSim, so will do my best to assemble a 396 torque motor.

I built this one at 10.3:1 static compression ratio. It worked out that way with 0.030" overbore, 72cc heads, flat-tops with 5cc reliefs, zero deck and Fel-Pro #1020 0.041" gasket (10.2cc's) recommended by Edelbrock. Only way I could see to get more scr with flat-tops would be to cut the heads and/or go bigger on the overbore. I didn't want to do that, so settled on less scr. Rotating assembly stack 10.155". Block cut for zero deck.

I figured that a professional porter could get another 10% over the Edelbrock published flow figures, so that's what I used for the Sim. Here are the flow figures I used....
0.100 97 70
0.200 168 124
0.300 215 163
0.400 256 188
0.500 292 201
0.600 297 220

If this is unrealistic, I'll cut back to the published figures and re-run the combo.
http://www.edelbrock.com/automotive_.../6000/6007.pdf

Forged pistons, Ross #99601 flat-top, 5cc valve reliefs cut by Ross for Edelbrock heads.

Comp doesn't have a real good selection of solid flat tappet cams for an FE, so I had to make do. Given more time, I could sort through some of the other manufacturers offerings and come up with a better choice....I'd like to see the intake closed a little later to lower dcr for use on pump gas. I extended the close 5 degrees after I had already run the Sim and made 583/555 with a 8.25:1 DCR....
http://www.compcams.com/Cam_Specs/Ca...?csid=946&sb=0

I ran this with a 750 carb, RPM intake and open small tube headers.....

RPM HP TQ
2000 161 422
2500 203 426
3000 262 458
3500 335 503
4000 406 534
4500 474 554
5000 527 554
5500 561 536
6000 576 504
6500 567 458
7000 539 404

Static compression ratio 10.3:1
Dynamic compression ratio 8.55:1 on Keith Black's calculator
Max volumetric efficiency 103.2% @5000
BMEP 211.3 @5000
Squish 0.041" with zero deck