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Low rwhp?

Joeseb87

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Newly built 355 stroker, l34 heads equivalent 670 vac secondary carb, very mild cam 214/ 214 @ .50, zero decked 10.1 to 1 compression had it dynotuned and got a print out of 152.5 RWKW does this seem low
 

EYY

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What manifold are you using and what are torque figures? I'd expect 180-210 rwkw with the banana manifold for your combo, so with a hywinder or harrop I'd expect around the 220-240 mark.
 

gtrboyy

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It's early heads not symetrical efi.

Smallish cam,early heads,dual plane & moderate carby size with 355 cubes wouldnt be expecting much hp but good torque.

Probably needs more cam to match the 355 cubes & 10:1 cr

More importantly how does it go/drive?

Assuming it's got tall gearing & small. stally
 

EYY

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Ah of course. Are they proper l34 heads, or are they late vk/stock vl heads? You can tell by the type of exhaust crossover (single bolt or two bolts diagonally across from one another in the middle of each head for the manifold)

The heads, ignition timing (what dizzy are you using - genuine Bosch? Has it been regraphed? How much mechanical advance? Initial?), jetting and mild cam will be the problems as mentioned by gtrboy.

Heads, compression and cam are the most important things. Most stock intakes are alright (especially the pre pollution manifolds) and the stock quadrajet is more than adequate. With that cam a dual plane manifold will be well suited as it won't make power above 5500 or so.
 

gtrboyy

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l34 type heads is ol' slang for bigger valves...kinda like stage 5 cam brah

It's probably just strangled top end strangling the 355/10:1 cr bottom end.
 

EYY

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Yeah if they're late pollution heads they have the l34 sized valves as standard, but the porting isn't anything special and the crossover heats up the manifold which doesn't help performance lol

Another question. What valve springs were fitted?

Tbh on a 308 a cam with 214 @.050 isn't even noticeable in terms of driveability and manners - I have one with similar specs in mine. I'd pull the cam out and fit something with [email protected] and .500 lift like a 286. Would get away without a converter too if it's just a streeter in a 355.
 

Joeseb87

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It's got a dual plane edelbrock performer manifold, msd pro billet dizzy, blaster 3 coil, 12 degree initial 30 total timing
 
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Joeseb87

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501nm of torque 3.36 gearing stock converter, also if I do the maths and multiply the tourqe x revs divided by 5252 it tells me it should be 210kw at the wheels am I wrong in doing this calculation or is the Dyno report wrong
 
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Not_An_Abba_Fan

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kW = Torque (Nm) x Speed (RPM) / 9548.

Your figure calculates back to 2200rpm, the above formula then equates to 115 rwkw, so 152 rwhp is about right.
 
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