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331 or 347?? Help Please...

  • Thread starter Thread starter Lilwhitepony
  • Start date Start date Nov 4, 2004
L

Lilwhitepony

New Member
Mar 1, 2004
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Nov 4, 2004
#1
  • Nov 4, 2004
  • #1
I'm not sure what I wanna do really but I have my motor down to the bare block and its going to get machined .030 next week. Right now I bought an E-cam, TFS Track Heat intake, and TFS Twisted Wedge heads that have alot of work done to them for top end. I need help deciding what I'm gonna do....If you can help I'd appreciate it!!!

email: marmat04@email.pct.edu
 
N

Notched

New Member
Apr 1, 2004
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Nov 4, 2004
#2
  • Nov 4, 2004
  • #2
well i've asked about this, a few times actually... well what do u want to do laster on? do u plan on forced induction? if so a 331 woul dbe ur better bet, they are stronger, and last longer.... was told the make slightly less power then a 347 but the strength with forced induction shoul dbe fine

if you going N/A then a nice worked 347 should go 11's. seen a few cars on here with a nice 347 run 11's all day long. its all based on what you want. forced inductino, n20, or N/A

i might buy a car with a worked 347 with n20, so that should be fine also.
 

TT91

Active Member
May 23, 2003
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Paramus, NJ
Nov 4, 2004
#3
  • Nov 4, 2004
  • #3
that e-cam is designed for 302 cubic inches, if you decide to go with a stroker, get rid of it and get something aimed towards your specific application, not a off the shelf 302 cam
 
L

Lilwhitepony

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Mar 1, 2004
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Nov 8, 2004
#4
  • Nov 8, 2004
  • #4
What kinda cam should I go for? I'm probably gonna end up going N/A
 
L

Lilwhitepony

New Member
Mar 1, 2004
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Nov 8, 2004
#5
  • Nov 8, 2004
  • #5
Also I know on a 347 you have to notch the bottom of the cylinders out for the connecting rods, do you have to do the same for a 331?
 
M

mackey

Active Member
Jan 25, 2003
1,284
1
38
Beverly, Massachusetts
Nov 8, 2004
#6
  • Nov 8, 2004
  • #6
Another vote for the 347... I would go with a custom ground cam to maximize your combo. There are many different places to get cams ground including Ed Curtis of FTI (Flowtech Induction).
 

hllon4whls

BANNED
Founding Member
Jan 17, 2002
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46
Covington
Nov 8, 2004
#7
  • Nov 8, 2004
  • #7
You need a cam matched to you combo and driving style.

A big huge cam will be fun for a while and will make tons of power at 3500 and up, but enventualy the fun wears off and it becomes a pain.

My vote is for a 331. A nice build and you should be looking at some nice HP levels.

It is not rocket science, but needs to be thought out more than, "I am using this cam because I heard it is fast." Lunati, comp, FTI, or your engine builder are good places to ask about cams. It makes a difference what gear ratio, vehicle weight, compression ratio, etc.

Most import thing to do when you build a motor is be honest. Be honest with what you want, what you expect and esp what you dont want.
 
8

87fcoupe

New Member
Sep 27, 2004
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Nov 8, 2004
#8
  • Nov 8, 2004
  • #8
Another vote for a custom cam.I would say 331 or 347 you choose,but definite a custom cam.
 
T

tjm73

Founding Member
Aug 3, 2000
2,418
2
48
Rush, NY
Nov 8, 2004
#9
  • Nov 8, 2004
  • #9
Lilwhitepony said:
Also I know on a 347 you have to notch the bottom of the cylinders out for the connecting rods, do you have to do the same for a 331?
Click to expand...

I have read that you do not need to notch the bottom of the cyclinders for the 331.

I vote 347 and I also agree about the custom cam if you are looking for maximum performance.

There are 2 types of 347 storkers too. One uses 5.4" rods and the piston pin intersects the oil control ring land. The other uses a 5.315" in which the piston pin does not interesect the oil control ring lands. I would use the later...in fact it is what I am saving up to buy currently.
 

N8Miller

I need NOS....make it 2 of the big ones
Founding Member
Jul 26, 2000
2,661
0
0
Kingston, PA, USA
Nov 8, 2004
#10
  • Nov 8, 2004
  • #10
matt,
you know i have a 331 and i enjoy it. would i do a 347 if i had to do it all over again.... doubt it. nothing against the 347, but i like the way that my motor runs/feels. It is setup for me, and thats what makes me happy.
I want more power now, but it has to do more with swapping bolt-ons (bigger t-body & MAF) rather than switching the motor. Either way, you will make the power that your looking for!

edit: i talked to you in another post about that Ecam. if your on a budget, get an OTS cam. There is nothing wrong wtih them, but get one that is setup for what your looking for. Something not too big, not too agressive., etc etc.......
 
M

manpowermustang

Member
Sep 25, 2004
228
0
16
Milwaukee, Wi
Nov 8, 2004
#11
  • Nov 8, 2004
  • #11
And another vote for 347. I did mine over the winter and notched the block myself. I was inpressed how easy it was to do. I would probably get a secnog set of crank and rod bearings for the moch up to notch it. If not you'll trash your new ones in the process. I love my 347 but have stock gears and it sucks with em, to boggy with to low of R's.
 

TT91

Active Member
May 23, 2003
1,536
0
36
Paramus, NJ
Nov 9, 2004
#12
  • Nov 9, 2004
  • #12
another vote for 331, and they DO REQUIRE the block to be notched.

Here u can see where my block had to be notched. It isnt much, but needs to be done in order the for rod bolts to clear.

 

TT91

Active Member
May 23, 2003
1,536
0
36
Paramus, NJ
Nov 9, 2004
#13
  • Nov 9, 2004
  • #13
Heres a better pic of the "notching"

 

KDK1988GT

Founding Member
Jan 7, 2002
1,937
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37
Fredericton
Nov 9, 2004
#14
  • Nov 9, 2004
  • #14
D.S.S for me

I went with a 331 D.S.S kit.. have had good luck with it.. working on making a few changes for next summer..

I did not need to "notch"

Went with a Comp Cam... 224 234 Duration and 555 565 lift.. and 1.6 rockers.
 
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