Help with Dispalcement
Life Time NCM #2196
Joined: Sep 2004
Posts: 82,596
Likes: 1,712
From: Converse TX
Under the curve is also for bragging only on the streets as my setup on the street has no traction until somewhere in 4th if I do not modulate the throttle
I personally would say that the $1500 is worth it to have the larger bore. However, you will be able to make 700whp on either motor, and if it is a true street car that is going to see the track very little, the 347 may make sense. You will have plenty of trq for the street, and more of it is only going to be a hindrance. The area under the curve will be better on the 402, but if you cant hook it, then there is no point. A lot of it is going to have to do with driving style and preference.
To summarize, I would get the 402 if it were me b/c I would eventually want more power and it is easier to do with the larger motor. Also, while at the current power level it is less stress on the motor. However, there is a reason why ECS and other shops use 347's in their big packages. With boost, especially in a street car, you dont need the larger cubes to make power. If the $1500 is really not in your budget, you will not be disappointed with the 347.
To summarize, I would get the 402 if it were me b/c I would eventually want more power and it is easier to do with the larger motor. Also, while at the current power level it is less stress on the motor. However, there is a reason why ECS and other shops use 347's in their big packages. With boost, especially in a street car, you dont need the larger cubes to make power. If the $1500 is really not in your budget, you will not be disappointed with the 347.
If you are on a budget get the 347 and spend the extra on supporting mods for this HP level, like a strut brace, better clutch for the MN6 and new Auto for those and output shafts and DTE strut braces--$1500 will not cover those mods I know I have them and just installed a OZ Textralia Twin Disk about $1300 shipped to my door. After 5k on my setup there in nothing but smiles on my face and one smokey clutch
If you want 700 rwhp you need more than a blower, TT to support it, just ask the others on this board and they will let you know once you hit these levels the game changes, and the cost increases big time. I did all of those mods when I put together my setup and plan for 20K as a min to do this to support this level, and labor on top of that if you are like me. Just some more food for thought for those wanting the big hp, what else you need to run with it. Just my 2c on this and for me I love getting blowing everytime I drive
Thread Starter
Burning Brakes
Joined: Feb 2006
Posts: 844
Likes: 46
From: Southaven MS
I made my decision and went with a 347 to be built by Texas Speed. I ordered it with Scat rods with arp 2000 bolts, stock crank, arp main studs, 8.6cc dish diamond racing pistons, and heavy duty steel top rings. I figured this motor will make all I can put down and it was cheaper. It should be ready in 3 weeks.
