Need opinion on 347 setup

[vikingz]

I'm going to stroke my 302 to 347 w/ the following the shop's guesstiment is around 475hp before the Paxton is this possible w/ this set up. 68 fastback using my cobra aluminum hi rise intake and cobra T oil pan.

302 longblock
early 351w heads
scat 347 crank
scat rods
custom forged pistons
speed pro rings
cl-77 bearings
fel pro/mr gaskets thru out
sfi approved flexplate
sfi approved balancer
erson custom ground blower cam and kit
arp bolts
double roller speed set
mellings hv oil pump and billet drive rod

 

[302 coupe]

not likely, I'd say maybe 360 for the non-blown version, maybe 450 with some boost. Its hard to make n/a power with factory head castings, even if they are ported a lot.

Got any ideas as to what compression, cam specs, carb, and head work?

 

[vikingz]

labor list

Thanks for your input I'll get those spec questions answered.

As for the labor this is what I have from them

Bore 30
torque plate hone
set deck and surface
set ring end gap
align bore (if needed)
relieve block for 347 kit
balance assembly
install oversize stainless steel valves
port modify heads
modify adjustible valve train
aluminum roller rockers, studs and guide plates

As far the carb goes I have a holly 4150 750cfm for the paxton but They suggest going w/ demon.

Thanks Again more info to follow.

 

[2bav8]

I agree that 475 is extremely optimistic on with stock heads.

Also, its hard to keep the compression low with a stroker, especially for a supercharger. Using cast iron heads wouldn't be my first choice in this situation.

 

[bmcelhinn]

Go with a turbo setup. Keep the compression around 9:1 and only run a little boost. That way you still have bottom end power from the motor, then the boost picks up hard around 3K.

 

[allcarfan]

as others have said, those HP numbers are very generous that you were quoted.

If you are going to run a high volume oil pump, I suggest you get a 7quart pan. That high volume pump will suck a stock pan dry.

Also, if you want to save some money, there is no need for an SFI approved balancer. Also, there isnt a NEED for honing to be done with torque plates (some will disagree with me on that one im sure).

Personally, id just sell the 351w heads...take the money from selling them, plus the money you were going to use to have them ported and have larger valves installed and get yourself a set of AFR 165s or 185s or some twisted wedges.

 

[bmcelhinn]

How much are AFR heads anyways?

 

[allcarfan]

1200-1350 depending on where you buy. You can get a set of used ones for under $1000

 

[bmcelhinn]

thanks!

 

[vikingz]

more info

Thanks Again for all your input the overall output of 500hp+ is plenty for my needs as to weekend cruiser from having just a 289 since Ive owned the car(84). I talked to the shop today and the compression will be 9:1 as far as the cam goes its a custom from erson designed w/ the paxton in mind erson has yet come back w/ specs. Also using hydrolic lifters. Its still possible on using the holly carb. The oil pan does hold 7.5 qtz.

David

Hey blkfrd were at in corona R U Im at Main/upper in moutain gate park.

 

[sin-city-customs]

Which 347 kit?

I just bought a new in the box 347 kit from someone in the paper and it has Keith Black pistons and Eagle rods, just wondering what heads your machine shop gave you the C/R for. I also have a Vortech S/C I may use, haven't decided yet, but haven't bought any heads yet.

Thanks,
Dave

 

[allcarfan]

I just bought a new in the box 347 kit from someone in the paper and it has Keith Black pistons and Eagle rods, just wondering what heads your machine shop gave you the C/R for. I also have a Vortech S/C I may use, haven't decided yet, but haven't bought any heads yet.

Thanks,
Dave

hope u dont plan on running a lot of boost on those hyper pistons.

 

[sin-city-customs]

I will be building the motor. I have done a few. My last motor was a 408 Windsor. Lasted until I sold the car. Maybe too much motor, went through 4 T-5 trannies.

Dave