i know i asked this question before ,but i guses i wanted some second opinon I am using my 71 2 bolt main block , i have forged JE Pistons , H-beam Eagle rods ,Steel 331 Eagle stroker crank ,and a Mallory 6 ingnitions box to retard timming for NOS. my engine makes 450 HP -450 TQ in gross messurment ,and spins 6500 rpm shifts.. i want to add a carb wet plate NOS system for a 100 shot of NOS, i feel good about my internals ,but my big question is my block going to stay together or split down the Valley , i gusses my question is any advice on NOS experince and how strong is 71 block is ,please if u talking any hp ## tell me if ur talking in gross messurment or WHP. thanks
Your block is a strong as the Mex block. Whatever the MEx block will stand so will yours, the only thing different between the two are the main caps. What splits them is excessive rpms and stroke, not the HP output. The NOS isn't going to help things though. If you want more power, build a bigger engine to start with.
Aren't stock blocks prone to lower end cracking at 550hp +?? Here's some grenade pics. http://www.460ford.com/forum/showthread.php?t=103161
It's not the power level that cracks em, it's the stress applied to the block with the longer rod throws and rpms combined that does it.
The 331 has a great rod to stroke ratio,however I`d agree w/ the other guys,550 on nitros would be pushing the envelope a bit.If you want to go that route,I`d get a Dart 4 bolt blk. & your worries would be over for a while,anytime you start throwing those power adders on it`s going to shorten the life of the eng.
Ultimately it depends on how it is used. A 600 horse 302 that only sees limited track use would probably last a long time where used soley for racing it would have a better chance for failure.
I like the ole saying the Carroll Shelby made famous a lot of years ago, "Horsepower sells cars and torque wins races", couldn't be more true. You say you motor is making 450hp and 450lbft of torque......at what RPM is this calculated.....that is a lot of torque for a little 347....... If you are actually making 450lbft of torque and are putting 100 shot of NO2, your block is the weak link and even if you only run it with NO2 once or twice a year................the block will come is going to come apart. Remember, torque is a twisting force......and with 450lbft of torque you are just about to the limit of the factory block. Even the Mexican block which has bigger mains and more material around the main web won't take much more torque than you are producing now.......a two bolt main OE 302 will not take the kind of torque you are going to throwing at it.............do yourself a favor and look for a 4bolt main block, or put a diaper on the motor and use the 100 shot..............and expect to be filling that diaper sometime in the future.......will all of your nice crank/rod pieces................IMHO
I agree! run it until it blows! that will give you an excuse to build a better stronger motor I was talking to my engine builder and was going for 500hp with a standard 302 running a super charger. well we were going to use a girdle to help hold it together but even with the girdle the 500 mark was pressing my luck so I decided to pickup a dart block and shoot for a grand to the wheels so now I have a motor to terrorize before the new one is built
The Mex has no more meat in the webs than his 71 block. The main caps are the only thing different between the Mex and the other 68-79 302 blocks (excepting the D8VE-A3A, which also has the big main caps)
