Neutral, 28oz, 50oz balanced??

[FastDriver]

ok good so the flywheel will be easy install then lol...
Yeah i'm doin a 331 since you don't have to clearance asnything on the block... anything over a 331 you have to start cutting.... and trust me i want to take as little as i can away from the block... It's a mexican block so it should be good to go i'm shooting to be at 550RWHP.... I think i may end up putting the forged crank in since i won't be able to sleep otherwise.... Yeah the turbo setup is able to put about 700hp out.... I know everyones allway hept up on displacement but i see no real reason for it. I like the turbo setup so i kept the stroker to a minimum.... I was even happy with the 306 had plenty of power on the street outa boost and just nasty in boost... So hopefully the 331 will give it a little more low end TQ and still be easy on the block....

You've been talking about using a dart block since the beginning of the thread. With a mexican block and only 550 rwhp, a cast crank will be fine. Mexican or not, you're still going to be pushing the limits of the ford 302 casting.

You don't have to worry about the block in regards to the 331 vs. a 347. The only "cutting" you'd have to do would be at the bottom of the cylinder sleeves where the increased angle between the piston and the connecting rod would otherwise cause it to hit.

The thing you have to worry about is the compression height of the piston. In a turbo application, you also want to set the ringlands as low as possible (Honestly I forgot why), and you want have as much piston skirt as possible to reduce the amount that the piston can rock back and forth between the cylinder walls. When you increase the stroke the only way to keep the compression height and the location of the ringlands is to decrease the connecting rod length. You're going to lose even more piston skirt, though. I don't think that rocking pistons is really that big of an issue. It's just one that has been mentioned to me. I chose to go with a 331 because I got a great deal on a billet crankshaft, and rods. If I could've gotten 5.315" rods of the same quality for the same price, I would've built a 347 turbo. The extra displacement wouldn't have any negative effects on the reliability or durability of the engine. The extra cubes might slightly help in spooling.

Chris

 

[Rick 91GT]

Go with a forged crank (cast should only be used up to about 600hp) also upgrade the rod bolts to ARP 2000 for piece of mind, although a stock 8740 should be fine in your application.

The small increase in stroke would help spool the turbo slightly, I have no issues building a 3.4 stroke 5.4 rod combo for a healthy turbo application.

The 3.25" stroke combo will still require you to notch the bottom of the cylinders for rod bolt clearance, no matter if you use a I beam or an H-beam. What rods are you using? What brand piston, and does it have a .912" or a .927" pin (I'd use a .927" with that power level) Notching the botto of the cylinder does not effect the strength in any way, you need the meat in the mains, the cylinder walls and the deck of the block. The Mexican should be good into the 700 range, I'd like to see 4 bolt caps on the center 3 but that will cost you another $600 or so easily.

Here's a picture of a notched cylinder wall for a customers 331, 3.25" stroke, 5.4" rod this was a Man-O-war block but the notch is the same....disregard the inside chamfer on the bore, that is to clear long strokes 4.0"+

When using forged internals Eagle or SCAT the Scat is slightly higher $$ for me to go internal depending on what piston and bore size is used.

:OT: Rich, I got your message, I am currently on vacation but have been trying to get ahold of one of my buddies about his shortblock. I have limted access depending on my wireless signal so I returning e-mails as I can.

 

[JS94cobra]

I am building a 331 with a stock block, cast crank and forged pistons/rods. Cast steel cranks are good to around 500 hp. Anything more I would go with the forged crank good to 1000 hp. The entire Eagle kit is under $2,000 crank, rods pistons, and if you are going to use a dart block not the mexican block I would internally balance the rotating assembly. I believe Eagle forged cranks are already internally balanced. I'm going with a 28 oz imbalance on my setup for the fact I will not be reving past 5500 and I am most likely going with a sq s-trim with only 6lbs boost so I should be ok.

 

[Rick 91GT]

Yes eagle has a new 4340 forged style internal balance crank out that is extre heavy in the counter weights so they usually do not require heavy metal to go "internal". I know I can get the kit in the $1450 range or so...

I would never spend the money to go internal on a cast crank...


The only issue with a CAST crank in a blower car is SNOUT strength, there is an extreme amount of stree put on the snout and a cast crank just is not made for that, that is why I try to push most blower customers to a forged set-up if at all possible.

 

[JS94cobra]

Yes eagle has a new 4340 forged style internal balance crank out that is extre heavy in the counter weights so they usually do not require heavy metal to go "internal". I know I can get the kit in the $1450 range or so...

I would never spend the money to go internal on a cast crank...


The only issue with a CAST crank in a blower car is SNOUT strength, there is an extreme amount of stree put on the snout and a cast crank just is not made for that, that is why I try to push most blower customers to a forged set-up if at all possible.

I understand what you are saying with the snout strength. As boost increases does snout stress increase too? If I were to run just 6 pounds would you say reconsider the blower idea? I didn't get a forged crank because of the limitations already on the stock block.

 

[88Stang331]

:OT: Rich, I got your message, I am currently on vacation but have been trying to get ahold of one of my buddies about his shortblock. I have limted access depending on my wireless signal so I returning e-mails as I can.

No problem, I was trying to not call you every day lol then i remembered you were on Vacation. Anyway, i will look forward to hearing from you when i hear from you.

 

[FastDriver]

Hi Rick,


Honestly, it sounds like this guy doesn't yet know what his goals are. He was talking about a Dart block and now a mexican. Regardless, I agree with your advice except for the following:

The small increase in stroke would help spool the turbo slightly, I have no issues building a 3.4 stroke 5.4 rod combo for a healthy turbo application.

That small increase (15-16 cubic inches) is not going to make much of a difference (less than 100 rpm) difference spooling a turbo. Why would you trade that small an increase in spool time for the strength and design of the piston? Especially considering you don't even have to if you use a 5.315" rod.

Chris

 

[Rick 91GT]

Hi Rick,


Honestly, it sounds like this guy doesn't yet know what his goals are. He was talking about a Dart block and now a mexican. Regardless, I agree with your advice except for the following:



That small increase (15-16 cubic inches) is not going to make much of a difference (less than 100 rpm) difference spooling a turbo. Why would you trade that small an increase in spool time for the strength and design of the piston? Especially considering you don't even have to if you use a 5.315" rod.

Chris

Chris, yes there are many variables with the longer rod, and many things can be done with a custom piston to give integrity and strength. It depends on budget, over all expectations and use of the vehicles. They say the longer stroke will help spool the turbo quicker but there are a ton of variables to that statement, which you and I both know.

I have a set of custom diamonds for a customer currently, 4.125" bore 3.4" stroke, 5.4" rod and they are very nice

 

[Rick 91GT]

I understand what you are saying with the snout strength. As boost increases does snout stress increase too? If I were to run just 6 pounds would you say reconsider the blower idea? I didn't get a forged crank because of the limitations already on the stock block.

The snout is stressed due to the blower pulley being so far out off the end of the snout. Belt tension also has a huge impact..

I have run cast crank blower motors for customers, you just have to be aware of the things I mentioned above, and tune conservativly.

 

[RyanSG]

LOl no at the time i didn't know what i was going to do, untill i got the $5100 price tag for just the short block... Unfortunatly yes i wish i coulda went with the dart, however hp wise as well as money wise the mexican block turned out to be the more reasonable choice... May not have been the best but to him his own..... I'm not to worried about the crank b/c of the 28oz balance and no blower, the person who owned my old short block (now dead) hd an s-trim with 15 psi, and i also had an sc-trim with 12 psi on it for most of it's life... then i went turbo and ran 13.5psi and blew it to hell basicly... however the spring is gone and a psi spring and boost controller is going in for the dyno tune over 6psi... I honestly just think my old short blok was going bad dude to improper balanceing (was getting vibrations) haveing a blower on tight enough to play violin on it..... got some pix for ya'll to see

So you can see why i was jumping to a dart block etc.... basicly was ranting, sorry for the confusion, i've never built a lower end or really had much of a choice in building one so i was pretty much searching for some help. But all the recomendations were def considered and thought about! Hopefully this one hlds up and makes a great street car for me to enjoy....

 

[FastDriver]

When you grenade a block, you don't do it half-assed do you?

 

[FastDriver]

did that damage your heads?

 

[fidstang]

LOl no at the time i didn't know what i was going to do, untill i got the $5100 price tag for just the short block... Unfortunatly yes i wish i coulda went with the dart, however hp wise as well as money wise the mexican block turned out to be the more reasonable choice... May not have been the best but to him his own..... I'm not to worried about the crank b/c of the 28oz balance and no blower, the person who owned my old short block (now dead) hd an s-trim with 15 psi, and i also had an sc-trim with 12 psi on it for most of it's life... then i went turbo and ran 13.5psi and blew it to hell basicly... however the spring is gone and a psi spring and boost controller is going in for the dyno tune over 6psi... I honestly just think my old short blok was going bad dude to improper balanceing (was getting vibrations) haveing a blower on tight enough to play violin on it..... got some pix for ya'll to see

[edited to remove pictures - Mod]

So you can see why i was jumping to a dart block etc.... basicly was ranting, sorry for the confusion, i've never built a lower end or really had much of a choice in building one so i was pretty much searching for some help. But all the recomendations were def considered and thought about! Hopefully this one hlds up and makes a great street car for me to enjoy....

OMFG! That hurts just to look at it. Sorry! I can only imagine what it felt like when you heard it happen and when you finally looked under the hood to see that!

 

[JS94cobra]

what internals were used on that block that blew?

 

[RyanSG]

lol

Yeah man i was pretty much ready to cry... got it inspected the day b4... was runnen great! went to work that day to show everyone... All i did was put it in neutral and was ready to turn the key off and that happend... Hard to beleive it went down at 900rpm eh? I still can't really beleive it lived for 15 miles of highway and back roads all the way to work and died in a parking space.... However the good this is the heads were in perfect condition! It did however shear the oil pump off, broke the waterpump in half, and bent my distributor and oil pump shaft... Def more then i had thought woulda been destroyed....
The motor was just a stock block, cast iron crank and forged pistons.... Like i said b4 it's had 500RWHP with a supercharger all it's life, and then a turbo at the end.. however i think the damage was done by the time i put the turbo on... I was getting vibrations etc at certain RPMs.... So i think it was on it's way.... My engine builder came back with a cost of about $1600 for the balanced and assembled short block... The new combo is goin to be
-331, cast steel crank
-Hbeam rods (forged)
-Probe dished forged pistons

I'm still trying to find a good cam to use but i guess i'll have to call up crane or comp cams and see what they would suggest etc... If you guys have any suggestions let me know i like knowen what other ppl are runnen and how they like it etc.... Hopefully though this motor will take about 520RWHP and be a great street/strip motor... Guess we'll have to see!

 

[fidstang]

Yeah man i was pretty much ready to cry... got it inspected the day b4... was runnen great! went to work that day to show everyone... All i did was put it in neutral and was ready to turn the key off and that happend... Hard to beleive it went down at 900rpm eh? I still can't really beleive it lived for 15 miles of highway and back roads all the way to work and died in a parking space.... However the good this is the heads were in perfect condition! It did however shear the water pump off, broke the waterpump in half, and bent my distributor... Def more then i had thought woulda been destroyed....
The motor was just a stock block, cast iron crank and forged pistons.... Like i said b4 it's had 500RWHP with a supercharger all it's life, and then a turbo at the end.. however i think the damage was done by the time i put the turbo on... I was getting vibrations etc ant certain RPMs.... So i think it was on it's way.... My engine builder came back with a cost of about $1600 for the balanced and assembled short block... The new combo is goin to be
-331, cast steel crank
-Hbeam rods (forged)
-Probe dished forged pistons

I'm still trying to find a good cam to use but i guess i'll have to call up crane or comp cams and see what they would suggest etc... If you guys have any suggestions let me know i like knowen what other ppl are runnen and how they like it etc.... Hopefully though this motor will take about 520RWHP and be a great street/strip motor... Guess we'll have to see!

Keep us informed! Don't forget the pics when the motors done.

 

[FastDriver]

OMFG! That hurts just to look at it. Sorry! I can only imagine what it felt like when you heard it happen and when you finally looked under the hood to see that!

It isn't necessary to repost 6 pictures. That just takes up more space and makes the page harder to load for people with a slow connection.

Chris