FE Power Forums
FE Power Forums => FE Technical Forum => Topic started by: Dptmachine on November 28, 2025, 09:43:39 PM
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I have a prepare Dove 427 SOHC set of heads with Comp Cams with specs that were lost. I had a machinist more talented than I, and he generated the following;
Dove 427 SOHC Heads
1. Comp Cams 953-16
Intake° Exhaust°
.010 106 106
.050 121 120
.100 129 128
.150 135 134
.200 139 139
.250 143 144
.300 148 149
.350 153 156
.400 160 165
.431 180 (.431 Max)
.450 170
.471 (Max) 182
.450 194 196
.400 203 206
.350 210 213
.300 215 218
.250 219 223
.200 224 228
.150 229 233
.100 234 241
.050 242 253
.010 254 ↓
Lift .613 Lift .560
Duration @ .050 cam 242
1) I have 2 different top oiler marine blocks that are std bore, but will require an over bore.
2) I have a 4 3/8" RPM crank and rods BBC journal
3) I have the tunnel wedge intake
4) I am looking at advice for piston manufacture recommendation, compression target range for performance/hot street,pump gas. I have access to non-ethanol premium at the pump (commercial account).
5) I don't have a car, tranny, rear-end, etc. I think it is kind of moot since I have the head assembled and spec'd already.
6) Where do detonation issues start to show-up builds discussed/performed/bench built?
7) Ferrera Valves 11/32" hollow stem F2024 2.280 Intake, F2023 1.900. Chamber not CC'd (I was leaning on Members knowledge). Plan is to take them and get CC'd in my Community College class (personal enrichment course)
Recommend Pistons compression, manufacturer, special considerations, etc?
Thanks,
Gary
Side note;
I have Coon Heads with a different set of Comps Cams specs (for blower build w/ Monroe Intake Manifold Australia, 8-71), Crower Billet 4.25 w/o rods or pistons. I will be looking for same advice in preparing this short block.
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sounds like a couple of nice builds.i am planning on a similar deal,but a 482 with pond block and ford aluminum heads that i have.also have a st of dove heads,one has damaged intake port that we will repair.
what i have found on the net and this forum,sohc can take a lot more duration at .050 than wedge heads.also they like compression,so 11-1 is minumum for a good pump gas.theres some good sohc builds on this forum.as far as piston,i will use racetech which is down the street from me,and they have done some custom pistons for mw before with good results.also diamond or cp ,but prices on them is sky high.
have 2 sets of cams,both around .600 lift,and isky max blower cams and a set of lsm cams with 282 duration at .05.not looking for big hp,just a thumpen street strip power for my 64 fairlane.
with your extra stroke,you can run a smaller dome and keep compression up.
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Overhead cams are always measured at the valve. In addition, the low rocker ratio generally demands a lot more duration to fill the cylinders. I usually run anywhere from 12-15 degrees more on an FE SOHC head than I do with my wedge FE heads.
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Pistons are available from CP and Diamond. I do not recommend any compression less than 11:1, even for a street vehicle, because those engines just don't seem to run well with low compression. Rocker ratio on the SOHC is about 1.3:1, which is why you need a lot more duration than you would need with a standard wedge FE to get the same valve action. Brent is correct that when comparing SOHC cams to a wedge cam, the SOHC will require about 12 more degrees of duration to get the same performance as an equivalent wedge cam. In light of this, your cams are really small, and if you want to run on pump gas you will need less than 11:1 compression, and as a result you will probably be disappointed in the performance of the engine. My advice (take it or leave it LOL) is to upgrade the cams to something closer to 260 @ .050, go 11:1 or something close to that on the compression. It will run fine on pump gas. Also, SOHCs normally only require 30 to 32 degrees total advance.
One last thing, make sure to pressure check the Dove heads.
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Somewhat echoing the other comments regarding compression and cam sizing. My thoughts are that the main issue with your parts list is that crankshaft. The 4.375 crank means that you have a large cubic inch package, accentuating the cam size limitations. Suggestions would be to either get much larger cams - or a much smaller stroke crank - depending on your desires for the package. If built as a "real" 427, the cams would still be on the small side - but much more appropriate. If you really want to use that long stroke you're going to need to swap out the cams - or build a Cammer that behaves like a "truck engine". If this is just a fairgrounds/parking lot/show car deal I guess it wouldn't matter - but that's not my style....