The Porsche 944 is a bit of a dice roll for Lemons racing. On one hand, it’s got a lot of the stuff that makes for a successful endurance car–good handling, strong brakes, enough power to stay out of its own way–but on the other, it’s relatively complex and potentially expen…
it's got a bit of a rod knock, but it should go another 20k mi
That is an awesome bit of motor-mayhem. Had to have been fun to be there when it happened.
That is very catastrophic. I know the blocks can crack, but it usually looks a bit different. I would be curious to see if the balancer, crank, and flywheel match. I also wonder if the balancer lost its balance or slipped. Of course fuel related detonation and high RPM are also factors. To add a bit of randomness, some blocks were definitely better than others. I know they were progressively lightened during the 1980s and early 1990s. Towards the end of 302 production, I can imagine that a lot of the molds were probably on their last legs.
That had to be bad luck. That engine was campaigned by Ford in the '60's. Even LeMans.
Holy crap. I've seen stock 302 blocks that split down the middle due to going above the 500HP limit, but I've never seen something that comprehensively broken
Ummmm.....Wow. Hope there was a warranty from the JY. I have never seen a crank just snap like that.
The Monster Miata I bought a couple of years ago suffered something similar. (It's why I was able to buy a completed swap V-8 Miata for $2,000) The 5.0 crank broke just ahead of the last two rods who then beat their way out of the block. Not quite as hard on the bellhousing but it broke off the input shaft of the transmission.
PO's "mechanic" then pulled the fancy heads and custom oil pan and slapped them on a new JY block pulled from an Explorer. Unfortunately he "repaired" the oil pan with JB Weld and black RTV. Some of that came loose and made its way into an oil journal. (this happened 6 months after I sold the thing) The stopped up oil journal caused the engine to lock up while the current owner was just cruising along a country road. Last I'd heard it has been rebuilt yet again and is a happy car.
jharry3 said:That had to be bad luck. That engine was campaigned by Ford in the '60's. Even LeMans.
The blocks were lightened and therefore weakened all through out the run, especially during the timeframe that block likely came from.
Also competition prepped engines from the factory and one pulled from a yard with some fancy parts slapped on it are not equivalent.
The crank may have been dropped at some point and the failure finally happened due to the abuse that racing generates versus just plodding along to the store or work.
I'd also be curious to know if the bellhousing adapter to the Porsche torque tube was properly built with tight enough tolerences? That is a LONG shaft and Porsche went through a lot of work to ensure the front of shaft was supported properly.
In reply to Stefan (Forum Supporter) :
Yeah, that would be my first guess, the trans adapter was made out of wood? lol One of the most successful lemons cars ran a 5.0 from an 85 mustang.
Endurance racing is running until it breaks and then try to run it even more.
Stefan (Forum Supporter) said:I'd also be curious to know if the bellhousing adapter to the Porsche torque tube was properly built with tight enough tolerences? That is a LONG shaft and Porsche went through a lot of work to ensure the front of shaft was supported properly.
Agreed. This is a pretty odd failure mode for a SBF.
The is why you should ALWAYS tow your lemons car with another lemons car. So you can swap the decals and continue the race.
Porsche 944 Body, Mustang Engine, Chevy Corvette Wheels...I hope it had a Honda ashtray and Toyota floor mats.
How much force is required for some of the metal detritus to make it through the firewall/transmission tunnel?
I would be glad I still had my right foot intact if I was driving a car that suffered that type of failure.
jharry3 said:That had to be bad luck. That engine was campaigned by Ford in the '60's. Even LeMans.
And it was really hard to make them last 24 hours. The Gulf team had to do a lot of work to keep them together and it took years to get it worked out.
JB Weld to the rescue!
What about a porsche powered fox body?
We had pretty good luck with the 302 in our champcar RX7. I believe it had about 100 or so race hours until a timing issue after switching carbs melted a piston.
Other than the "Boss" 302 block that had 4 bolt mains and "Mexican" and late "B50" blocks none of the production 302 blocks were intended for high performance use or in this case racing. If used that way you need to make a number of mods to keep them together. In keeping in the sprit of Lemons most teams using this engine don't do any of that but I have to say that the mods made to mate this engine to the Porsche drivetrain would have to be the main factor in this failure or the engine was just near the end of it's life to begin with.
BTY- The 289 and early 302 blocks were heavier castings and did hold up better but as mentioned over the years Ford lighten the blocks to save money. The Boss block is nearly 50 lbs heavier than the lightest of the 302 production blocks.
Long time since I've been inside a good ol murican V8, but should a plain-jane 302 JY grocery-getter have a super-deep cast oil pan, intake ports the size of those, notched piston crowns, and an externally balanced flywheel??
jharry3 said:That had to be bad luck. That engine was campaigned by Ford in the '60's. Even LeMans.
And the A/Sedan racers would break cranks on a regular basis. And this was ith the 28oz-in external balance, not the 50oz-in of the newer engines, which are more likely to break the crank at extended high RPM. Although it's usually the FRONT journal that breaks off not the rear!
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