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Why can't a SBF last like a SBC?


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Why can't a Ford 351W be built that will last? What is the difference between this block and a SBC 350?
No reason at all. Mine (302 stroked to 327) is on it's 7th year.

 

Even so, comparing a 350SBC to a 302SBF isn't really a fair compairsion; with the extra cubes it's going to be easier to get to the required power and torque levels for AI. A 351W is certainly a better comparison, but there aren't very many in AI. Of those, they seem to work fine. Robin's is on it's 3rd year with no problems, and he spins it to speeds that I won't disclose, but I guarantee are higher than your 350's are spinning.

 

Finally, given the sample size, I don't see where the SBC has proven to be any more reliable. Stan Berry and Rustic seem to have plenty of troubles with them.

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Finally, given the sample size, I don't see where the SBC has proven to be any more reliable. Stan Berry and Rustic seem to have plenty of troubles with them.

 

Yea... I had trouble that first year... threw a rod right through the side of the block... and one through the oil pan!!! But no real trouble since then Mine is a 383... put a bit more than 400/400 to the wheels.

 

Well then... what this thread tells me is that one of the main reasons given for allowing the swap (to keep more mustangs on the track by giving them a reliable motor) is hog wash.

 

I would say that it's obvious at this point that brand variety is not important to the directors... but I suppose it doesn't matter that much to me. I'll still be out there beating the shit out of my 3500 lb 4-door in an effort to support my side business. It's just a shame there isn't any effort to attract more diversity.

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As far as the ford main webbing cracking, about 4 years ago we started putting 4 bolt splayed main caps, on the 3 middle caps, and we have not had a block crack since. Tom Patton (past SCCA GT2 national champ) has been running this set up in his 289 sunbeam tiger with a sportsman block for over 4 years, and has not had a problem since. He had cracked 2 sportsman blocks previously. The engine we built for Jay Andrew ( AI National Champion) uses a stock 5 liter block with this conversion, and is on its 3rd season. We used to use a lot of girdles, but still had cracking problems. Now we either put the 4 bolt caps on, or leave the block alone. Paul, Paul's Automotive Engineering

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Paul makes some interesting points about how to make an SBF last and perhaps this would prevent some failures. However, I feel I need to address Chris's two points as they really bother me.

 

As to lack of evidence of SBF failures, I can point you to well over a dozen and probably closer to two dozen folks who have grenaded SBF's in American Iron due to block or crank failures. Read the lastest AI-West report and you'll see that Keith Parker's 331 expired with only a few weekends on it. I bet when they tear it down that something in the block broke which allowed the crank to walk and snap the rod. Jeff's motor is in my mind an anomaly as I honestly can't remember two weekends in a row where I didn't hear a report somewhere in the country of a blowed up SBF on track. Also note that I included the Modular 4V Ford in my thinking for allowing the Mustang SS. Hal Massey and Andy Bowman can spin you some tales about how well those motors last as they have each been through at least three or four of them in the last few years. So, like it or not, there is a problem with these engines not living long and healthy lives in a roadracing environment.

 

I also disagree that we've done nothing to try and promote the use of different chassis in AI. I've spent hours of time measuring cars, researching performance data, and then trying to get enthusiasts with different makes of ponycars and other domestics to come out and try racing with us. Despite the fact that I'm a recovering Mustang addict, I have really tried to get AI to be something other than Spec Mustang. I realize that I'm not going to win any arguments with some of you about brand loyalty and that train of thought, but I also think it's a bit unfair to accuse me and the other directors of not caring or not doing anything to try and grow the series.

 

So, enough ranting and I look forward to seeing more tech on how to make an SBF live in this environment. My approach was to spend the money for a 302-R block and then pay attention to both oiling and revs. Before I took those steps, I managed to kill 3 302's of which the blocks were stock late-model, Sportsman, and Mexican. Without the investment in the bottom end, these engines don't seem to live too long.

 

-JWL

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pendejoengineering

After tear down it was found that keiths motor failed not because of a engine part failure but because something had entered the oiling system. It is currently being examined to find where the particle had come from. if not for that the rod bearing would not have failed and that engine would still be running today.

 

Pen

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I also disagree that we've done nothing to try and promote the use of different chassis in AI. I've spent hours of time measuring cars, researching performance data, and then trying to get enthusiasts with different makes of ponycars and other domestics to come out and try racing with us. Despite the fact that I'm a recovering Mustang addict, I have really tried to get AI to be something other than Spec Mustang. I realize that I'm not going to win any arguments with some of you about brand loyalty and that train of thought, but I also think it's a bit unfair to accuse me and the other directors of not caring or not doing anything to try and grow the series.

-JWL

 

I apologize if offence was taken from my comment(s). But I have not heard of the efforts you are referring to... but I'm very glad they are being done.

 

To most of us, the only "action" we see is in the form of rule changes or rule interpretation. And in this arena, there doesn't seem to be any activity to encourage the use of anything except a blue oval.

 

I have even mentioned in the past that I would be willing to add some F-body parts to my business so that I could offer a contingency for Chevy guys in the Midwest... although I'm not sure it would be a good (read profitable) move for me. As it is now, the contingency programs don't seem to offer much for Chevys.

 

I would be more that willing to discuss such things off-forum if you would like.

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Paul makes some interesting points about how to make an SBF last and perhaps this would prevent some failures. However, I feel I need to address Chris's two points as they really bother me.

 

As to lack of evidence of SBF failures, I can point you to well over a dozen and probably closer to two dozen folks who have grenaded SBF's in American Iron due to block or crank failures. Read the lastest AI-West report and you'll see that Keith Parker's 331 expired with only a few weekends on it. I bet when they tear it down that something in the block broke which allowed the crank to walk and snap the rod. Jeff's motor is in my mind an anomaly as I honestly can't remember two weekends in a row where I didn't hear a report somewhere in the country of a blowed up SBF on track. Also note that I included the Modular 4V Ford in my thinking for allowing the Mustang SS. Hal Massey and Andy Bowman can spin you some tales about how well those motors last as they have each been through at least three or four of them in the last few years. So, like it or not, there is a problem with these engines not living long and healthy lives in a roadracing environment.

 

I also disagree that we've done nothing to try and promote the use of different chassis in AI. I've spent hours of time measuring cars, researching performance data, and then trying to get enthusiasts with different makes of ponycars and other domestics to come out and try racing with us. Despite the fact that I'm a recovering Mustang addict, I have really tried to get AI to be something other than Spec Mustang. I realize that I'm not going to win any arguments with some of you about brand loyalty and that train of thought, but I also think it's a bit unfair to accuse me and the other directors of not caring or not doing anything to try and grow the series.

 

So, enough ranting and I look forward to seeing more tech on how to make an SBF live in this environment. My approach was to spend the money for a 302-R block and then pay attention to both oiling and revs. Before I took those steps, I managed to kill 3 302's of which the blocks were stock late-model, Sportsman, and Mexican. Without the investment in the bottom end, these engines don't seem to live too long.

 

-JWL

 

As your experience so vividly shows all your hard work and efforts all too often go unappreciated and I for one appreciate all that you and NASA do to promote this class and that is one more reason why I am building a car to run with you guys.

 

Regarding SBF I have been building them since the early 60's and per my personal experience if the proper detail to oiling and careful attention is given to assembly they can be almost bullet proof. This will be the ultimate test in October and November when I run one in Mexico for 3000 miles. Keep up the good job.

 

Gary Faules

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Jeff's motor is in my mind an anomaly as I honestly can't remember two weekends in a row where I didn't hear a report somewhere in the country of a blowed up SBF on track.
Sure, there are plenty of reports of blowed up SBF's, and there have been plenty in our region, but I can't think of any in the OH/IN or Midwest regions that have been due to broken blocks recently. Plenty of bearing problems, valvetrain failures, etc., but we seem to have the block problems in check. Honestly, most of the failures to me seem like poor choice of parts, machining, or assemby.

 

For reference, my engine is a Sportsman block with a main girdle, forged crank & rods, and up until recently wasn't spun over 6250. Is it on borrowed time? You bet, but at this point it has given me more than enough trouble free service to be called "reliable".

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Grizlbits
Sure, there are plenty of reports of blowed up SBF's, and there have been plenty in our region, but I can't think of any in the OH/IN or Midwest regions that have been due to broken blocks recently.

 

Brian Groth split a block in Iowa 3 weeks ago.

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bmrracing

When I changed over from a vintage 65 mustang to a SN95 the 1 thing I notice almost imediately was loss of oil press in turns . With the old front sump pans I never lost oil press for even a instant, when I used the same engine in my 95 I lost oil press several times even with a accusump and ended up braking a Boss 302 crank and splitting a Boss 302 block ! I now have a Dart block forged crank etc . What has helped is oil restricters that make the mains primary, oil restricted to the lifters, Accusump,increased oil capacity in the pan, and a external oil pump It must be working the engine is 3 years old I turn it 7000. all the time every shift so I believe the way to make them live is details details on assembly and a outstanding oil system. I also found that Cantons 7 qt pan really isn't 7 qts in the sump actually it is 4.5. I read a article about oiling and at any given time there is 4 qts flying around the inside of the crank case and only 1 in the pan of a stock engine at 3000rpm and that is anybodys brand. So if you can imagine what 6-7000 rpm does + throw in turn G and brakeing decell into the mix a 7qt pan is at best marginal.

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I would say that it's obvious at this point that brand variety is not important to the directors... but I suppose it doesn't matter that much to me. I'll still be out there beating the shoo-shiddily-diddily out of my 3500 lb 4-door in an effort to support my side business. It's just a shame there isn't any effort to attract more diversity.

 

Not me - I'm totally against it. I think Fords ought to be Fords and Chevys ought to be Chevys. But that was all discussed in another thread.

 

As far as SBF's lasting, I'm on my 3rd year with a stock Ford Crate motor. All I added before putting it in was a HV oil pump and 7qt Canton pan. I will admit that I'm a little down on HP but that's because of the motor I ordered (GT40). I'm planning to order and run a new one next year (w/ the new 302 block) which will be one with a little more HP.

 

It's all about finishing races, good driving, and a total package. The motor is just one piece... It's really just that simple...

 

Good luck,

Ed

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To add to my original question:

 

"Why don't you guys build 351's instead of stroking a 302?"

 

We had 305's in our AGS cars when we went AI. After a couple seasons it was obvious we just couldn't spin them hard enough to get the hp and torque. Pulled them and built real simple 350's. Why spend all kinds of money on an inferior 302 when junkyards are full of 351's? I've heard several horror stories about 302's but have yet to hear anyone that broke a 351.

 

Sidney

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I would say that it's obvious at this point that brand variety is not important to the directors... but I suppose it doesn't matter that much to me. I'll still be out there beating the shoo-shiddily-diddily out of my 3500 lb 4-door in an effort to support my side business. It's just a shame there isn't any effort to attract more diversity.

 

Not me - I'm totally against it. I think Fords ought to be Fords and Chevys ought to be Chevys. But that was all discussed in another thread.

 

As far as SBF's lasting, I'm on my 3rd year with a stock Ford Crate motor. All I added before putting it in was a HV oil pump and 7qt Canton pan. I will admit that I'm a little down on HP but that's because of the motor I ordered (GT40). I'm planning to order and run a new one next year (w/ the new 302 block) which will be one with a little more HP.

 

It's all about finishing races, good driving, and a total package. The motor is just one piece... It's really just that simple...

 

Good luck,

Ed

 

Well said. Nail on the head! While there is no problem pumping up any Ford small block it's obvious that many are expecting far too much of them. Simply throwing lots of money into any engine will not make it reliable but in fact "simplicity" will. Building engines that produce too much horsepower comes at a price and that price in not cash... it's reliability. Too much horsepower makes for too little longevity. SBF have been around and involved in racing for years and they do not have a history of grenading until too much has been asked of them.

 

351's are a good choice as well but not as many have knowledge of what the key to building one is. Someone else said it earlier... proper installation of parts, quality of parts, and attention to details are what is key in a good motor. Too many guys are doing things to their engines simply because "That's what the other guys are doing."

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white_2kgt

So what I'm hearing is to build 351's vs 302's, what's the weight difference between a 302/351/SBC 350? I've got a Mod motor in there already, so I see each of them as the same amount of work to get it up and running.

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So what I'm hearing is to build 351's vs 302's, what's the weight difference between a 302/351/SBC 350? I've got a Mod motor in there already, so I see each of them as the same amount of work to get it up and running.

 

I will be interested to see what facts you will end up with. Don't forget there are several versions of 351's and while I do not know which one is best I do recall from years back some of them were bad right from the start thus making them less than desirable. One more thing to consider that I would be interested in learning about is I wonder if there are as many choices to chose from with regards to selections of various components (and price) as there are for 302/289 sb's.

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King Matt

There are plenty of parts choices for the 351-size block, especially if you want to build one using Cup-type parts. Probably the only thing that is somewhat lacking is a wide variety of EFI intakes.

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D Algozine

It seems interesting, that these Ford engines that don't hold up very well finished 1-8 at the a Nationals, and only one GM in the top 10.

If you're going to agrue that most of the engine failures are Fords, you also have to consider that nearly all of the engines are Fords.

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It seems interesting, that these Ford engines that don't hold up very well finished 1-8 at the a Nationals, and only one GM in the top 10.

If you're going to agrue that most of the engine failures are Fords, you also have to consider that nearly all of the engines are Fords.

 

BINGO!!!!

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It seems interesting, that these Ford engines that don't hold up very well finished 1-8 at the a Nationals, and only one GM in the top 10.

If you're going to agrue that most of the engine failures are Fords, you also have to consider that nearly all of the engines are Fords.

 

That's because they are the only ones that can keep up. LOL.

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bmrracing

A 351W will weigh in at about 45lb more than a 302. The only good 351 block is the very first series the 69 and 70 . the 71 isn't to bad but after that they get thin just like the 302. If you can find early 289 blocks they are very heavy in comparson to a late 302 about 5lb the early blocks don't break like the latter 302 block the late models are a very thin casting a process ford has been doing since the early 70's was to thin the castings out for cost savings and also better casting processes. The late 302 really should not be bored over .020 but routinely is taken out to .040 ford never designed the block to be rebuilt. The biggest down fall for the 351 is it has a very heavy crankshaft you really don't want to turn a stock bottom end 351 to more than 5500 you will be asking for trouble. Bearing life is not good in them because the main journal is almost 3.5" so that creates higher oil temps. There is no reson a AI car can't run a 302 for several years after all all you are looking to get out of one is around 320 rwhp and 330lbft of torque . that is not a very exotic engine.

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There is no reson a AI car can't run a 302 for several years after all all you are looking to get out of one is around 320 rwhp and 330lbft of torque . that is not a very exotic engine.

 

That's exactly correct Bill. Even back in 1968 Shelby put 302's in the GT350 with very little work at all including hydraulic lifters and their rated power (SAE gross) was estimated at 315 hp (235 kW) @ 5000 rpm and 333 ft·lbf (451 N·m) @ 3800 rpm. With today's technology and the long list of goodies available there's no telling what can be done to quench the thirst of those who can make an engine last. In my opinion, part of being a good driver isn't always about winning but in fact how you make your equipment last.

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that is not a very exotic engine.

 

Not until you try to have it make that power from 3000-6500 with big compression and restrictor plates...

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bmrracing

I have been running a 306 for 3 years 2 in AIX it makes 420 rwhp at 6750 rpm routinely spins well past 7500 . It is a Dart block the rest is essentialy over the counter parts. you can get exotic and make decent power, and the small block Ford can live. what kills them is trying to take power out by detuning, thats why I went to AIX I rather run there and let my engine live.

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I hear ya, Bill.

 

That's why the mosquito sprayer 187,000 mile 350 is coming out and a new 305 with stock heads is going in. I can't wait to see what 70 more RWHP will do.

 

Let 'er rip

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