347 Ford Build

[cgarb]

In process of putting together parts for a 347 I want to build. So far I have a scat cast crankshaft, a set of eagle SIR rods, and a set of probe flat pistons, a factory roller block, MSD distributor, Victor jr intake and a set of performer heads. I want to port the heads myself, with the aid of a local shop that has a flowbench. I want to make a decent bracket style engine. What is some reasonable numbers for the performer heads once they are ported? My goal is to get as close to 500hp as possible on race fuel. (Seems to be about the limit I have read on a factory block, and my rods)in The compression with a 60cc head would be almost right on 11 to 1, if I mill the heads a bit more would be possible I suppose. Looking at using the factory roller set up. Want to shim the lifters to limit the travel, run 180 seat and 470 or so open valvesprings. Lightweight 300M steel retainers also. I found a camshaft that is 280/285 adv 240/245@.050 and .605/.625 lift with a 1.6. The cam is found with 110 lobe separation. Would this get me in the ballpark (provided I do my job correctly on the cylinder heads) to meet my goal? In a bracket car with a 4000 plus converter that weighs 3000lbs would I gain anything by changing the separation tighter, to 108 or 107 maybe?

[blykins]

Camshaft should be chosen last. It will depend on how the heads flow.

You'll get about 67 different opinions and about 23 different arguments from here on out, so I'll just leave you with that.

[ClassicComp]

Big question is how fast do you want to go?

[Walter R. Malik]

As long as you start with the bigger valve Performer heads you should meet your target.

[lewy-d]

I'm helping a friend build a Very similar combination.
There are 2 part numbers for the performer heads. I "think" they only varied on intake valve size.
what is the part number of your heads?
Is this pump gas?

funny..Walter & I on the valve sizes at the same time!

[Mark O'Neal]

You'll need about .300/.220 @.600 to do what you want. If you don't have heads yet, get a set of AFR 185s and bolt them on.

You won't need race fuel.

11.0:1, cam somewhere between .575 and .600 (HR) and a decent manifold and you'll meet your H/P goals. I have never seen any advantage to adding lift in excess of the heads peak flow in the hundred, or thousands, of motors we've dynoed.

But...to answer the two questions to asked, I have no idea how far those heads will go, and yes you will make your goal with that setup.

[Carnut1]

You will be pushing the limits of a stock roller block so block prep will be important. Post up stock head port and chamber pics and stock flows to give us a baseline. Thanks, Charlie

[cgarb]

Honestly, I never really gave the 185 AFR's a thought. That would save a pile of grinding and flowbench work, but that's not how I roll...lol. I'm going to look at these Performer heads Monday. Depends how cheap they can be picked up. I have most everything but the heads and camshaft. The heads are damaged, guy says it sucked a valve in....whatever that means. I assume a damaged exhaust seat and valve. He's one of those make me an offer type of guys. I hate that because I don't like offending people by offering something really cheap...lol. What would a set of those be worth. For what you get, the edelbrock's are expensive new, The AFR's are a way better deal. I'm going to assess the damage, but if they can't be bought for under 3-4 hundred bucks, it's a no sale for me. Needs all new hardware, a seat at min and machine work.

[SupStk]

I'm considering either a 331 or 347 build for my vintage Mustang.

My experience has shown the Victor Jr will be the bottleneck if your heads flow much over 260cfm. It will limit you to around 500hp. If going that way be prepared to spend some time reworking it. The Super Victor flows a bunch more but it has distribution problems. It can be bandaided with stagger jetting. Out of the box its worth about 30 or so hp over the VicJr.

Another vote for the 185 AFR heads. They flow as advertised, valve job is good, guides are properly sized and the components seem to be of good quality. They get high marks on the ones I've been around.

Don't think you will have any problem meeting or surpassing the goal of 500hp.

[SRS_Chris]

For your reference, this is an engine I build a few years back. If I remember correctly, the intake track (heads and intake together) flowed about 270 cfm. I am currently working on a head and intake combination for the same shortblock (new owner) that consists of a set of Trick Flow Twisted Wedge heads and a victor jr intake. It is still a work in progress, but preliminary flow bench testing shows that this combination should flow about the same as the AFR/Funnel Web deal once finished. Something to note, we started dyno testing with a 750cfm carb, but the 1,000 carb was worth significant power everywhere on the curve. The key is to test, test, test. Every combination of parts is slightly different. Another point of interest is that this was achieved with a stock E7 roller block and it lived. As mentioned previously, proper machine work and tune up is extremely important. The first sign of a rattle and it will make two pretty useless four cylinders... been there... done that.

http://www.yellowbullet.com/forum/showt ... 7+dyno+srs

[ClassicComp]

and I have a set of AFR 185s that would better in someone elses shop than mine..

[bigfoot]

Don't make too much HP or you will split the block in the lifter galleries lol....my 347 with dart Jr steel head..1.94 valves Victor Jr intake 750 Holley with a 550 lift hydraulic cam ( non roller ) l have the svo 2 bolt main block..chassis dyno at 350 hp ..

[MadBill]

Big Joe reported that on (I believe) a 600 hp 408", a prepped Super Victor made about the same power as a prepped Funnelweb (an original, not one of the several generations of successively worse copies) but only with the 8 hp gain from a 1" open spacer, which made no difference with the FW.
As mentioned above, the Vic Jr. would have been down at least 30 hp on this combo. (which is not to say it's a bad choice for your milder app.)

[Walter R. Malik]

As mentioned above, the Vic Jr. would have been down at least 30 hp on this combo. (which is not to say it's a bad choice for your milder app.)

EXACTLY ... the last manifolds I evaluated on the dyno for this conbination, (now realize that these tested manifolds were all port matched), the Victor Jr. was down 20 some horsepower from a Trick Flow. However, was up a little over 15 lb/ft of torque at peak torque and up a similar amount at RPM's below that torque peak.

PEAK power numbers is not always where the best intake manifold for THAT application, will show itself.

[cab0154]

I wouldnt be porting those heads myself when Fox lake has a CNC program for it for $1k