302 max torque and power?

Lynn Larsen

Lynn Larsen
Ross,

The issue Drew was referring to, re: cracking, is not necessarily an issue that 4 bolt vs 2 bolt main caps is going to resolve. It is an issue with the meatiness of the webbing that holds the whole block together. Below is a picture of the result of too much power and not enough webbing strength:
 

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Sandy

Gulf GT40
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That is crazy, I have never seen something like that. How common is that picture for the stock blocks?

Sandy
 

Lynn Larsen

Lynn Larsen
Sandy,

I don't think that happens that frequently since not many stock blocks don't get taken to the >600 hp level. But it does happen as is witnessed by the fact that the guys in Scott's post are making girdles to add strength. Also, those that have seen it happen say that is happens exactly like the block in the photo.

Lynn
 
This will help make more power as well I believe. Because of less cyl. distortion. My engine's cylinders will be honed with a cyl. deck torque plate, mains torqued & valley girdle installed. This should go a long way to keeping the bores round during operation.

Oh and Sandy a 80's -90's vintage SBF will do this sometimes as low as 450 HP, depending on how loaded the engine block gets. Meaning a drag race holeshot where the tires really hook good.
Just my .02

Scott
 

Russ Noble

GT40s Supporter
Lifetime Supporter
Ross,

Get to the corner as fast as possible !
That was pretty much the entire Can Am theory.
Build as much HP as you can afford.
Build as much brake as you can afford.
As long as you can accelerate and decelerate faster than the next guy, the corners will pretty much take care of themselves.

Happy Easter !

Regards,
S

Sad but true. Scott has hit the nail on the head, although there are always exceptions to the general rule. I would add put the biggest stickiest rubber on that you can afford.

Someone's bound to jump in and say this is a Cobra Forum penis building exercise, :dead:but if Ross is running in a class where the top guys have 600hp, he's fighting with one arm tied behind his back if he's giving away 150 hp or more.

I agree with Flatchat's statement though, that superior aerodynamics and handling will help negate some of the hp defecit. Unfortunately even if you do outdrive and pass a higher hp car in the corners etc, and the crowds love that, the start/finish is usually along a straight, about where you get gobbled up by the hp!:mad:

The SBF engine forums are full of photos like Lynns the consensus seems to be 450 hp as the max safe limit for the stock 302 block although some have been documented at less than that. No doubt if the tune is way out, that's not going to help.

Some guys maintain that girdles are only good for stopping your parts falling onto the road after the block has split. I wouldn't know, but I'm sure an engine builder will comment. Personally, unless the regs say you have to run the stock block, I'd rather save the money and complication of the girdles and put it towards a stronger block. Whatever the V8 Supercars run seem to be pretty reliable.

Slight thread drift here, I've hunted on the net for regs for the V8 Supercar motors but haven't found anything. I wanted to have a look at them just out of interest. Can any Aussies point me in the right direction?

Cheers,
 

Russ Noble

GT40s Supporter
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My block is listed on the build sheet as a B50 and I'm pretty sure it's a Sportsman.Please correct me anyone if I'm wrong.It was originally 2 bolt mains but has been upgraded to 4 bolt during a 2003 freshen up.Steel crank and rods so I don't think there will be a strength issue.
Ross

Ross, not wishing to rain on your parade but I just stumbled across this new thread which talks about B50 blocks.

Ford Racing B50 Block - Hardcore 5.0 - The Mustang Drag Racers Forum

It's not a bad SBF forum, IMHO, with a lot of participation from suppliers etc but take it for what it's worth, it's the only comment I've come across on them. But then I haven't really been looking. At this point the thread has only been running for a day, so there could be a lot more info to come in yet.

Cheers
 
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302 R Block, billit rotoating assy, 10.3-1 compression. 536hp/422lbft of torque. 8100 rpm shift point 9000 rpm red line.
 

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Ross Nicol

GT40s Supporter
I'd say it's a 302 with a 9000 rpm rev limit and the 422 torque.Nice motor!
What size are the carbies? they look like IDA webers.Russ I'll keep an eye on that mustang site. I think when the guy says the cracked B50 blocks were only 400hp motors there is more to it,abuse was mentioned but possible poor assembly wasn't.
Ross
 
It's a 306, (.030" over). Everything in it was designed by me. None of it is off the shelf.
Those are IDA's. It dynoed with an 830 Holley pro series on a super Victor intake. I have having a custom EFI stack intake made for it with 52mm t-bodies.
The only time I have seen a 5.0 block break like that is when they try to put 17lbs of boost to it for to long.
 
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Russ Noble

GT40s Supporter
Lifetime Supporter
Ross, if you're coming over for SFOS as planned in Feb you don't want to spend all that money to be sitting in the pits going nowhere with a pool of oil and water under your car! Bearing in mind what it's going to cost to get here a few thou for a decent block is a drop in the ocean. Hope you can come over with a 600 hp motor!:pepper:

Cheers,
 

Ross Nicol

GT40s Supporter
Don't worry Russ this motor has been running in a race car all it's life and has proven to be reliable. It powered the Daytona coupe ( that Peter Brock was killed in ) from 2001 through to 2005 when I bought it and I have raced it for nearly a year now.So it's very much proven and no doubt credit must be given to the builder RPM engines in California who reckon it was ok to rev to 8000 rpm all day long.I've been changing gear at 7000 but I may up that to 7500 if what I'm about to do improves the breathing up there.
Ross
 
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