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View Full Version : 50 oz vs 28 oz balancing on strokers

Mitch P
08-23-2002, 06:41 AM
I have been told 50oz balancing on strokers won't work by some, will work by others. I have some $$$ invested in good SFI balancer and flexplate already from the 302; if I decide to go stroked, what will work best?

Thanks.

Mitch
racer7088
08-23-2002, 07:16 AM
Mitch,

With the 50 Oz deal you have to remove a LOT of metal from the crank since it's made to be able to go 28 even with heavy parts. If you have reasnable parts and the heavy balancer and flywheel you have to remove a tremendous amount of weight compared to the 28.
BigDawg
09-08-2002, 11:59 AM
If your going to a stroker, don't even consider a late model 50oz imbalance. Without proper aftermarket balancing the accuracy of the 50 oz. kits is less than desired. Also it's more difficult to aftermarket balance at 50 oz, sometimes less precise and usually is more costly - Go 28oz or 0oz for 6500+RPM
fordman
09-08-2002, 02:34 PM
it may cost a little more ,but i would go with 0 internaly balance.I have a 393 and it has worked fine for me for 4 yrs. Good luck :)
Mitch P
09-09-2002, 04:55 AM
Got 28oz balancing, as the motor won't go above 6200.
ForceFed306
09-30-2002, 01:12 PM
Perfect topic for me to jump in on...
I had my motor built by a local engine shop and the guy that ran it was a Ford supervisor recommend through a friend of a friend. That was the first screw up. Unfortunately, he has caused me more grief than happiness. One of the many things he screwed up included balancing my rotating assembly. The crank was ordered as a 50oz. imbalance piece (forged) because I had a 50oz. SFI Motorsport balancer. Instead, they sent me a 28oz piece. My engine builder sent it with the balancer and flywheel to the balancing company and told be (after the fact) that they had to remove a ton of metal to balance it. Well, duh! I was a bit t'd with both him (for not notifying me first) and the retailer for sending the wrong crank.

Long story short, I got the 28oz. crank in a with less metal and a 50oz balancer. It's a Pro-line crank and it's accompanied by Eagle H-beams, Probe Pistons, Early 70's Mexican block, and Probe steel girdle. I just pulled the lower end for an inspection (<50 miles on it and a dyno pull) and decided to install H-bearings and run a hone through it (it has some very light scracthes). While I'm in it, would it be worth replacing the crank with a 28oz piece?

The combo should make >500rwhp and spin to around 6k.

Thanks,
Andy
FAH-Q Racing
10-01-2002, 12:46 PM
The only time a 50oz balance is ok is when building a grocery getter 408 using a 400m crank, and thats because to use a 28oz requires expensive mallory metal in the crank to balance, as to where if you use a 50oz on that particular setup, you dont have to add mallory metal.
ForceFed306
10-01-2002, 02:05 PM
So your basically telling me to throw a 28oz crank in there and get rid of the 50oz balancer. Right?

Thx
Mitch P
10-02-2002, 04:51 AM
50 oz balanced parts serve a purpose as bolt-ons to a stock motor to meet SFI requirements. As was pointed out in the first responses to the thread, 28oz or internal balancing is better because it moves the weight off the ends of the crank. If you have it apart, replace the crank. ProPower performance will set you up with a decent SFI balancer and flywheel for a fair cost.
ForceFed306
10-02-2002, 05:50 AM
Thx - needed someone to justify the added expense!

Andy
Mitch P
10-02-2002, 06:02 AM
Andy - look at your signature tag. :D I quit using mine because of all the mods I listed. There is absolutely NO justification for the money we spend on our cars - but we do it anyway!
ForceFed306
10-02-2002, 08:06 AM
That's no joke. The toughest part of it all is explaining it to my future wife. LOL. Now I'm trying to decide if I shouldn't just buy a 331 rotating assembly and sell the crank,rods,pistons I have. Although, my logic (do it while your in there) usually gets me into trouble later! :)

Andy
Mitch P
10-02-2002, 08:12 AM
It's worse if you're already married like me - the nagging doesn't stop! Brian Tooley from TEA feels there's more power and potential by not going stroked; he bases this on the current Renegade field and the hp gained vs. the weight penalty. I got a nice deal on mine and it priced out the same as a 306 kit. I'm using a Sportsman 302 block (some like it, some don't).

Since mine is basically for short street cruising and local Ford events, I'm not concerned with weight penalties. But, because a stroker is considered a power adder, I'll have to step up to a different class that allows combos - stroker and blower. I'm only a trophy racer anyway. If we can get into the low 10's - high 9's, that's all I care about.
ForceFed306
10-02-2002, 09:30 AM
Married, man - that's why I'm doing it while I still can!

My initial thinking on the 306 was that I could get away with more boost, rev higher, and leave the starting line smoother. With a 331, of course the weight penalty gets you but the torque gain can make up for it. If I have any sense left, I'll stay with the 306.
I'm more concerned with getting the car running period than planning my racing career. Try 3 years without being able to even drive your stang!

Andy
Mitch P
10-02-2002, 09:35 AM
Yep, single is definitely the time. My wife likes the classis 'stangs with no mods whatsoever.

Your idea on the 306 is good; I wanted to go in the same direction but when I got offered a good 342/347 kit, I had to go with it.

Mine has been down about a month or so. We've been really lucky about it breaking; we were going 10's with almost 100k on a junkyard shortblock that had pre '93 forged pistons and a main support. I really want it back up and running, but I'm taking my time and doing a little bit every day.

Good luck!