stroker for 4.7 liter

A friend would like to put a stroker in his engine. He has a 2003 Dodge Ram with a 4.7 liter. Where can I find a stroker if there is? if no, are there aluminium heads for this engine?

I am not aware of either being available for hte 4.7, assuming by aluminum heads you mean aftermarket because the stock head is aluminum. However, there are places that do offer performance stuff for the 4.7.

http://www.airram.com/custompage.php?page=18

Probably gonna have to go to smaller rod journals and offset grind the stock crank.

Factory heads are aluminum, they could be ported like other heads but I don't know of any aftermarket heads.

The rod journal is only 2" on a 4.7 so you're looking at Honda journal size for off the shelf rods. Going from a 2" to an offset 1.88 journal only gains you .006" stroke does it not? With a .030 overbore that is 5 cubes. Not worth the bother IMHO.

Has anyone flowed a 4.7 head? That number would give you some idea of the engine's potential.

2 ways to get serious power out of a small package, spin the wee out of it or boost (or both...). OHC make the former a little easier but a 5000lb truck needs torque so my vote would be for boost.

Kevin

My vote would be to find something else to hop up

Where's the sport in that?

Kevin

Well, my wallet is too flat for that kind of sport.

I believe it would give you 0.24 if you can use the original surface on the outer edge..

Some of the Dakota guys have been able to drop in gen III hemis and run them on the stock computer.

Bingo!!!!
A lot less work swapping a 5.7 in them modifying a 4.7.
Plus more potential with the 5.7.
Matt

Yes it's .120 not .012. My math sucks.

I can never remember if you get 2x the offset for stroke increase or half.

.240" increase would be a worthwhile increase.

Kevin

With a .120 longer stroke and .030 overbore it would be a 316 CID instead of 287 with a head that barely flows better than a 318 head it will run about like a 318 but a lot quicker reving although power and TQ should be similar, maybe a smidge more.

I know the 4.7 truck I am driving now has way less TQ than my old 318 truck, both 5 speeds and 3.55 geared 4x4.

If offset grinding, then the Mitsubishi 1.850 rod journal size could be used.

All of you are wrong on the stroke increase. It is just slightly less than the difference in the rod journal sizes. So going from 2.000 to 1.88 is 0.112" But the grinding wheel has to contact the rod surface all the way around so you'd maybe end up with 0.105" stroke increase.

Using the 1.85" journal you could get maybe 0.135 stroke increase.

Using an example from the real world, the 440 crank with its 2.375" journals can be offset ground to 2.200" and stroke increases from 3.75 to about 3.91.

To the OP: This is an engine that has no real factory support for high performance use. It is well-known to have durability problems. There are no high performance heads for it, and the stroke increase I outlined above wouldn't be worth the trouble.

IF you must keep the engine because of your country's licensing rules then supercharging would be the best answer. Even 0.4 bar would increase performance quite a bit.

If there's any way to use a Generation III Hemi that would be the way to go. You'd probably double the apparent horsepower with a stock 5.7.

R.

Your math is as bad as mine.

2 - 1.88 = .120

Kevin

the you have to double the 0.120 because at the top of the stroke it is 0.120 higher in the cylinder and at the bottom of the stroke it is 0.120 lower in the cylinder or as someone above said the grinder has to contact the journal all the way around so lets call it 0.110 and double that for the full stroke increase so total increase would be 0.220

That's a theoretical maximum increase in stroke by offset grinding the pin, it'll be less in reality, especially if you need to grind the crank an undersize. Figure .020" less as a rule of thumb. And you don't double it to calculate the stroke increase.

The math works out such that if you have a .120" smaller journal size you offset grind to then your stroke increase is... .120", less the .020' I mentioned, so figure .100" increase.

http://www.hotrod.com/how-to/engine/ccrp-9812-engine-boring-and-stroking-fundamentals/

There's adapters you can get to put 4.6 intakes on 4.7's, including the supercharger set up from the Terminator engine, that's kind of cool

I have a bad 4.7 in my shop and some 1.85 journal NASCAR rods, maybe I should try building one of these with the solid lifters that one place sells... there are tons of rigs on CL for sale with blown up 4.7s in em.

You are incorrect.. Using simple numbers say starting with a 3.00" stroke which is 1.5 inches either side of the centerline of the crank, you offset grind 0.10 it adds 0.20 inches total to the stroke.. that is 0.10 inches at TDC from 1.5 to 1.6" on the compression side of the crankshaft centerline and 0.10 inches at BDC again from 1.5' to 1.6 inches on the bottom side of the stroke..
Using you method is physically impossible.. you can not add stroke to one side of the stroke and not add the same to the other side..

Rumblebee, you are forgetting ONE IMPORTANT THING:

Assuming you leave the outermost edge of the rod journal and grind all of the 0.120" off the inside, you have only moved the center of the rod journal out 0.060". Yes that's on both sides of the circle, but it's 2 X 0.060 and not 2 X 0.120.

I believe rod length of the 4.7 is 6.12. Deck height is 9.09.Stock stroke is 3.405 Piston compression height computes out to 1.26" Rods weigh 565 grams
See writeup here:
http://www.allpar.com/mopar/47.html

To the OP: Maybe an easier way to get more power would be to find a 2008 - 2013 290hp version, there were quite a few improvements according to the writeup.

It's an interesting question, thanks for asking it!

R.

Dog days is right.

Thanks for your answers.
My friend use LPG and he has to change or repair heads, compression is very low. Engine has 180000 miles.
So we are gonig to dismantle engine, check all, pistons, bearings, rings... and he is going tu upgrade it with new ported heads, new intake/throttle body and maybe new pistons for more compression.

In that case the newer heads, pistons and rods would be a good addition. I think they made some combustion chamber changes. Seriously, look into it before you spend a lot of money on the older stuff.

R.

Sure, and you know we are in FRANCE so with shipping + customs, you can add 50% from the original price.

With the cost of shipping you may want to strongly consider the option of a different engine.
Once you round up all the parts and shipping you might be able to score an engine and dump it in a container for the ride over there.