306 vs 347 stroker

90mustangGT said:
I'm with you. Not to be insulting, but I base thing by what happens at the track. When I see a car run really good, I've got to find outs what's happening. It's all about what's on paper, the timeslip that is.

The only paper to care about are the pieces that fly outta your wallet when the pistons make eggs outta your cylinders j/k:D
 
  • Sponsors (?)


k my next question is, will the 347 sound diff then my 306?...also what kinda estimated power numbers would a 347 stroker with the following mods put out, im in the hunt for 10's..(car went 11.4 on the 306 with a 150 shot) x-cam,ford svo roller rockers, torker intake, holley 650dp,pullies,msd 6al,blaster coil,twisted wedge heads, ford racing dizzy,
 
90Notch said:
... I don't know where to begin but yes the 1.8L has 4 cyl and this doesn't matter for the forces you're talking about. The force you're talking in each cylinder is what counts and having eight cylinders doesn't make a difference or create more force in the equation. Also having the same force applied in a smaller cylinder results in more force being distributed throughout the surface. The more you write the more your ignorance comes out..

Oh, I see, rotating assemblies don't play a roll in the equation, I'll write that down on my note pad .....(jot, jot, jot)............... and a 1.8 Honda applies the same force as a 347 Ford ... okay got it, thanks for exposing my ignorance :nice: Maybe we should put heavy rods on 7 cylinders and rebalance the assembly. :shrug: I don't know where to end ...

90Notch said:
By the way last time I checked 8.437"-1.195"-1.716"(3.433"/2)=5.436" scooter.
So let me spell it out since you're having trouble with this concept...5.436" rod + 1.716" stroke + 1.195" ch equals a 8.437" deck height.

Oh I get it, you do the division first :bang: .... I knew you were trickin' me. :nono:
I like this formula a lot better though ... thanks for making the necessary changes for me :nice: So to figure out deck height I use this formula right ('cause piston crown is always designed dead even with deck surface.)

.... also my calculator makey 8.347" not 8.437" ... either my calculator is messed up or there was a double-typo that brought the assembly line to a hault :shrug:
 
It all comes down to several factors:
1. What are you using the engine for?
2. Who built it?
3. What materials were used?

Most of the popular 347 kits have good offset piston ring designs that help alleviate some of the oil control problems seen in 347's from 10 years ago. CHP chooses to typically use a stock bore on their engines, to add longevity. The 347's tend to have more high-rpm blow-by then a 331, due to excessive rod angle. A 331 will typically make more usable power throughout the lower RPM's, but the 347 will best those numbers up high. As such, DSS and CHP will typically say that if you plan to see high rpm open-track use, go with a 347. If you plan to drop the engine into a daily driver, go with a 331 or 306. Most builders will tell you that the power difference in the three engines is negligable, depending on the components used. They tend to push the 331's and 306's to most customers because everyone seems to have hard-ons for 347's. Anyway, get what fits your intended use, select a quality builder and buy quality components.
 
Rick 91GT said:
Ford down graded them to 400HP for a reason, I know some that have split with 400HP NA on an engine dyno, when others have taken more in NA form. I was just at Maple Grove to spectate and catch up with some friends, got some nice sun as well ;) Hope to have my lil monster out in August, neighbors are going to love when I finally start it up..lol
PM'ed you Rick.

Lol. Yeah, I'll bet they will. :D

I would. :nice:
 
loud 95 said:
... A 331 will typically make more usable power throughout the lower RPM's, but the 347 will best those numbers up high. ....

I think you got these two backasswards ... at least from claims made by DSS ...

Plus on various dyno comparisons and configurations (street/strip bulids), seems DSS is close ... stating that a 347 will best a 331 by as much as 40 ft# down low but a 331 is capable of making more hp up top :shrug:

But like you said, it's all in the components used and who the jerk on the end of the wrench is. There are just so many variables, but I believe under the general rule-of-thumb this is accurate.