347 Cast or Forged ??

[Pops Fun]

Hi,
Well I have decided sort of... I want a 347 shortblock and Pauls Auto will build it. The car will be street driven during good weather, some runs at TNT at the drag strip.
The question.. Two actually

Cast crank or Forged crank..

Here is what Iam thinking.(til I change my mind) I have just a little more that 281rwhp now and should get close to 340/350 with the short block. The block and the cast crank will be the limiting factors , What I've read says that it should be good to 500rwhp right, or forged (more money) and be extra safe, the block being the weakest link?
Even if I add a supercharger down the road (no money for a few years if ever) another 100hp I should still be good??

Balance .. is there any advantage in the different balances:

50 oz can keep my own flywheel and balancer(balancer upgraded)
0 oz. change flywheel (aluminum) and balancer
28 oz. change flywheel (aluminum) and balancer

I had 281wrhp before high flow cats

Dyno tuned chip
TFS TW Heads -- ported
Steeda 19 Cam -- might do a custom cam(Buddy Rawlins)
Cobra Intake -- ported
FMS 65mm T/B
Pro-M 75MM MAF
Steeda 24# injectors
H&S 1.72 Roller Rockers
MSD 6al, Blaster coil
Walbro 255 LPH
Cold Air Kit,
Under Drive Pullies
Ford 3.73 Gear
Flowmaster Exhaust,
Mac Shorty Header
High Flow Catted H-Pipe
Timing chain and Gear
Lowered (Eibach 52/94)
Steeda Tri-Ax
Tokico Shocks & Strut

 

[Joes95GT]

Putting a forged crank in a stock block is like using a knife in a gun fight. It just doesn't make sense. Keep the RPM under 7000 and the horsepower at the crank under ~525 and everything will live (WITH A GOOD TUNE!!).

The balance doesn't make much difference in a street car. If you're on a tight budget, go 50. If you want to upgrade the flywheel and balancer (you should atleast update the balancer), I'd go 28 because it wouldn't be too much more.

Joe

 

[Grn92LX]

Pops, what condition is your current 302 shortblock in? Reason I ask is because its probably more cost effective to just add some boost now rather then build a 347 using your curent 302 parts. The heads are good but everything else is too small and will really prevent a 347 from making good power. If you are dead set on a 347, a cast steel crank is more than enough (and its lighter) for a stock block build. I would not suggest building a 347 stroker and adding boost on a stock block. Done right, thats 600rwhp and way past the safe limits of a stock block. My friend just went through this decision and as hard as it was, he went with the dart block for his 347.

I researched my ass off on this subject and (for me) I came to the conclusion that to do a 347 the right way to make the power it should (400rwhp+) its gonna cost too much money, so I decided im going with a Vortech SQ. I will be placing my order in a few actually. All said and done, the supercharger will make more power (not as much low end as the stroker though) and cost a lot less. Have fun deciding, cars are fun huh?

Mike

 

[Pops Fun]

Pops, what condition is your current 302 shortblock in? Reason I ask is because its probably more cost effective to just add some boost now rather then build a 347 using your curent 302 parts. The heads are good but everything else is too small and will really prevent a 347 from making good power. If you are dead set on a 347, a cast steel crank is more than enough (and its lighter) for a stock block build. I would not suggest building a 347 stroker and adding boost on a stock block. Done right, thats 600rwhp and way past the safe limits of a stock block. My friend just went through this decision and as hard as it was, he went with the dart block for his 347.

I researched my ass off on this subject and (for me) I came to the conclusion that to do a 347 the right way to make the power it should (400rwhp+) its gonna cost too much money, so I decided im going with a Vortech SQ. I will be placing my order in a few actually. All said and done, the supercharger will make more power (not as much low end as the stroker though) and cost a lot less. Have fun deciding, cars are fun huh?

Mike

Yea cars are fun.... Have done the vortech debate, yes more HP with actually less work and near the same money.., Reasons:

a fresh engine as a base can't be all bad
Low end torque
Gas mileage ?? if I have it Iill have my foot in it

I could talk myself out of this No back you indecision back


Steve

 

[blksn955.o]

If your going to get a 347, I would at very least get a sportsman, and would suggest a dart/r302 block. I have a friend who has a 347 with very heavly ported TF TW heads (4k worth of work) custom ultdyn. cam, and matched intake/carb setup. at the track he blew the trans. at the 1/8th and still went 12.0 at 124mph on the brakes....N/A. He had a Racers edge (or is it razors) forged crank, oliver rods, JE pistons in a stock block (retarded idea, esp. for the price of the rotating assem.) he split the block in half after less than 3k miles..... He is now wanting to go the route of a dart block but he is looking at replacing a few pistons and rods (that are not cheap).

IF your going to go forged and big, step up to a good block. The only reason I say maybe a sprotsman, another guy had a 331 with a sportsman block and a main support and it lasted fine, no issues with power on a 150 shot and afr 165's going 11.2 @ 123. However, they are not as good as the dart/r302 stuff.

 

[Joes95GT]

If you can find them with a standard bore, BOSS or Mexican blocks are much stronger.

Joe