Building a 347 stroker

Got to do it on the cheap so I have to reuse everything basically. Will I be choking it if I put my old parts on it?

GT40 iron heads ported
Explorer intake honed
24lbs injectors (too small?)
Stock fuel lines and rails
190lph pump
1.7 roller rockers
E303 (will this cam work?)
65mm TB/EGR spacer
73mm MAF
1 5/8 shorties (will probably go long tube)

On a stock 89 block this combo ran a 12.53 @107 could I see high 11s with the 347 and a tune?

On other threads you guys talked about 28oz as aposed to 50oz balancer/flywheel

dirtysohc said:
The only time you need to go to a lighter balancer is if you plan on turning higher RPM's. I've had many engine combos over the years turning between 6500 and 7000 RPM and always with a 50oz balance. I would say if you were to go above 7000 Rpm's I would go with a 28oz or 0oz internal balance at that point. But just switching to a stroker set up doesn't nessecitate changing the 50oz set up.

90mustangGT said:
Your right dirtysohc, but most kits come as 28oz and to have them balanced to 50oz takes a lot of cutting on the crank and unless you "got the hookup" then it is quite expensive so it's almost cheaper to go 28oz and it does have it's advantages. I don't understand why the companies that make strokers dont' do 50oz because most of what it's going into is 50oz setups. They would sell more of them.

I went with a SFI balancer (pioneer) with a Alumimum Flywheel (spec) so of course mine cost a little more.


Rick 91GT said:
Yes you can go 50oz but it takes a lot of material out of the counter weights, to do it properly it should be taken off radially which is expensive. Going to the lighter inblance in better on parts and bearings.

Is it preference maybe, but I think you'll find most builders prefer the 28oz or internal balance over the 50oz on stroker combos, cast or forged crank.


So I should just buy the 28oz balancer/flywheel and no problem?

Does a stock block have to be bored out to a 306 to make work with the 347 kit? (I'm sure heard that it does)

Thanks in advance for your info!
 
you can have the motor balanced to whatever you want (50oz,28 or 0) Yes a 347 is punched .030 over. . . if you dont then you have a 342. I dont think you will see high 11s at all, you will need a better cam and heads to get to the 11s
 
YES, if you order a 347 kit you will HAVE TO have the block bored .030 over which is only about 125$ at most machine shops, you will also have to have the cylinder skirts notched in order for the rod bolts to clear (another 75$) If staying NA i dont see any reason why the 24lbs wont be enough and give you room to grow, the stock injectors can support 400hp. For racing purposes it is strictly personal choice between 331 and 347.(i built a 331) The 347 will wear out the block faster due to the angle the rods will want to push the pistons against the cylinder walls.....(this is all in theory and hear say). Flat tops are exactly what they say. . . they are level with the blocks deck and most have valve reliefes cut for piston clearence. . . dome pistons are domed above the deck of the block and also have valve reliefes. . . most people go with domed pistons in order to gain more compression and depending on the size of the cylinder head combustion chamber you might not be able to run pump gas at all. Keep in mind that if you plan to go ever go with a canted valve style head (such as twisted wedges) You want to be sure that the valve reliefes allow for that also! I would suggest going with probe as they have valve reliefes for both inline and canted valve heads
 
24's i think are too small. hell, people were telling me i was going to choke my 347 with AFR165's/e-cam/performer rpm intake.

i upgraded to 185's, trickflow R-series, and kept the e-cam and re-used the 24# injectors, which i regret. but im adding a blower and new fuel system this winter anyways, so no biggy :D
 
1991vert said:
24's i think are too small. hell, people were telling me i was going to choke my 347 with AFR165's/e-cam/performer rpm intake.

i upgraded to 185's, trickflow R-series, and kept the e-cam and re-used the 24# injectors, which i regret. but im adding a blower and new fuel system this winter anyways, so no biggy :D

I only have mild port GT40 heads and will not be able to add any other go fast parts so I guess small TB and smallish head willkeep the flow down so maybe the 24lbers will work for now.

Thanks for the info

I haven't seen any "budget" 331 kits yet, are they around?

I have seen 347 complete kits for around 6 to 8 hundred, am I asking for problems on the first run with these kits?
 
83 Capri 5.0 said:
I only have mild port GT40 heads and will not be able to add any other go fast parts so I guess small TB and smallish head willkeep the flow down so maybe the 24lbers will work for now.

Thanks for the info

I haven't seen any "budget" 331 kits yet, are they around?

I have seen 347 complete kits for around 6 to 8 hundred, am I asking for problems on the first run with these kits?

If your talking about the eBay kits, I've heard a lot of bad stuff about them. The say is usually true "You get what you pay for".
 
the GT40 heads can work with a good port job and for the injector i'm building my engine with 30 pounds but with 24 is not too bad get more fuel press to help and for the kit i realy like propower (www.propowerparts.com) street strip kit they come with forged I rods (suports 600hp), forged Pistons (suports 1000hp) and bearings rings and stuff for 925 bucks not bad i have kit #990-213447ssft for $925

P.S The first thing you should do is change the cam stay away from alphabetic cams, get comp cams XE276HR-12 (35-328-8 good stroker cam) and is designed to be used with 1.7 ratio roller rockers.
 
Just to steal the thread... There is a 347 Short block for sale in the " SE Classifieds" down lower on the "Southeast" menu.

28 vs the 50 oz! it really is up to the guy that you are going to get to balance!! 5 speed flywheel , he can use the 50 oz weight. and AOD, there isnt enough metal to make the balance!! 28 * is the choice of most all balancers for that reason!!

Pistons.. IF you are going to Blow or Turbo.. then the dished pistons are the better to keep the compression where pump gas can be used!! N/A then the flat top is good! Dome is a racing fuel only kinda thin.. cool??

Cam.. the E is a bit small for the 347!! Inexpensive cams?? the TFS2/ F303/X303. They are PROVEN Performance with 347!! The 24's will work fine on a street/strip engine!!

GT40s with the port work will be fine!! after the combo is deep into the 11's n/a then maybe think of upgrade to alum. Dont get into the gotta have BIG heads, and Custom cam thingy!! what you have will be a killer street/strip car and a blast to drive and 11 sec car on the streets!! IF you dont make the 11's it isnt the combo you are building.. cool??

Just me.............................

Thumper
 
83 Capri 5.0 said:
Got to do it on the cheap so I have to reuse everything basically. Will I be choking it if I put my old parts on it?

GT40 iron heads ported
Explorer intake honed
24lbs injectors (too small?)
Stock fuel lines and rails
190lph pump
1.7 roller rockers
E303 (will this cam work?)
65mm TB/EGR spacer
73mm MAF
1 5/8 shorties (will probably go long tube)

On a stock 89 block this combo ran a 12.53 @107 could I see high 11s with the 347 and a tune?

On other threads you guys talked about 28oz as aposed to 50oz balancer/flywheel

So I should just buy the 28oz balancer/flywheel and no problem?

Does a stock block have to be bored out to a 306 to make work with the 347 kit? (I'm sure heard that it does)

Thanks in advance for your info!


There is an old cliche' that holds true no matter what BS is spread throughout the internet...

"302 parts make 302 power"

Anyone who tells you the small stuff that works well on a 302 combo, works the same on a 347 is only blowing smoke up yer azz.

If you want to do this "on the cheap" then get a good cast steel crank, I-beam rods with forged piston package in the stroker kit. A really decent kit from Probe is just under $900 and it's plenty good enough for big torque and 350+ RWHP with the right peripherals.

Sell your iron heads and intake to a 302 guy and look for a used set of Twisted Wedge heads and a Holley Systemax 2 intake. These are about the minimum for a strong running 347 engine. Unless of course you want a 300 HP 347 that get's beat up by mild 302 cars.

Remember, a cheap combo is one thing, a stupid combo is another!

Ed
 
aleborjas said:
the GT40 heads can work with a good port job and for the injector i'm building my engine with 30 pounds but with 24 is not too bad get more fuel press to help and for the kit i realy like propower (www.propowerparts.com) street strip kit they come with forged I rods (suports 600hp), forged Pistons (suports 1000hp) and bearings rings and stuff for 925 bucks not bad i have kit #990-213447ssft for $925

P.S The first thing you should do is change the cam stay away from alphabetic cams, get comp cams XE276HR-12 (35-328-8 good stroker cam) and is designed to be used with 1.7 ratio roller rockers.

Have to keep the e303 cam for now, but will keep that comp cam in mind for the next up grade.

Thanks!