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I may be out in right field all on my own here, but to me the 71 Mustang in general is one of the ugliest mustangs ever produced right behind the Mustang II. I'd take a 4-eye fox body over a 71 any day of the week.
I have heard/read that many times over the years.......

R
 

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As I recall, the factories were not above supplying automotive publications ringers that were modified and/or tuned for better performance than the production versions sold in the dealerships.
Yes, and one would have to "assume" that this practice was done across the board and not just to the version of Mustang that a person doesn't like..........meaning, a 375HP 429 puts down better numbers than a 335HP 428 (both Drag Pack cars) in magazine tests from two different years, let's say 1970 and 1971, or it could be a CJ comparo, 370HP 429 and 335HP 428.............You would have to "assume" that Ford provided a "prime sample" in 1970 for testing and also a "prime sample" for testing in 1971............and the same magazines tested both, possibly even the same magazine editor(s), and the numbers were documented as they were posted.........

..................and then the whole "under rated from the factory" thing...........If one is "claimed" to be under rated, then you would have to assume that all were under rated, not just the personal preference car........

Back in the 1999-2001 time period Mustang Monthly did a 6 Mustang "Big Block Blowout" feature, 3 Mustangs were chassis dynoed here in Lakeland Florida same day, same dyno, same big fan blowing across the "open hood" cars. 1 - 1970 Grabber Blue Boss 429, 1 - 1967 390 GTA and my 1971 429 SCJ. A few weeks before in Georgia, 1 -1967 Shelby 428PI, 1 - 1968 Shelby 428CJ and 1 - 1969 Shelby 428CJ..............All cars had to either be restored or original drive train with no headers, smog pumps in place factory dual or single point dist., factory as possible cams, etc...............My car put down the best numbers at 248rwhp and the BOSS 429 was right behind me.........The Shelby's in Georgia all put down numbers in the mid-230's to almost 240rwhp..........The GTA 390 C6 was below 200rwhp, and I will just leave it there.....Also the Shelby's had both 4spd. and C6 in the mix for testing.

The owner of the BOSS 429 was crying foul and kept wanting another pull.........mid way through the clean/crisp 3rd pull the upper hose blew off and sprayed antifreeze all over his restored engine compartment and windshield and even on the roof paint, I grabbed towels and started to clean, quickly clean........The owner was saying something was the matter with the dyno.......and me? I had no idea, it was my first experience on a chassis dyno and it was a weird feeling AND 250ish rwhp Horsepower out of a "375HP" 429 Super Cobra Jet was kinda disappointing I will admit.......

So the magazine editor (Jeff Ford) who had overseen these three pulls as well as the pulls in Georgia to verify each pull for authenticity asked me if I knew that my car was running rich........like "real rich" as it pulled through the rpm range?.........I told him I have been trying to get the car to run right (clean up) with it's 1971 Ford Shop Manual listed 71 pri. jets and 83 sec. jets in the oem D1Z Holley 780, but could not get the car to not "Black smoke"............and I REALLY did not understand why, I am sure it did not act that way from Ford........So in the end, we did another Magazine feature called "Dyno Tuning for Power" in maybe 2001?......On a portable dyno in Lakeland Florida in the back grassy lot of the Mustang Monthly office. We spent the better part of an afternoon tweaking that D1Z 780 Holley to attempt to achieve nice clean/crisp dyno runs like the other Mustangs/Shelby's did in that previous dyno feature.................FINALLY, after many Holley bowl drains and re-jetting and secondary spring changes to lessen or increase the opening I ended up with 70 pri. and 76 sec. jets (down in the rear from the factory 83's) and the car picked up about 50rwhp and was just under 300rwhp........I could have tweaked it more but I was done, that engine had never been apart/restored, it showed 31K original miles and it currently had an original 4.11 Ford gear installed, when I bought it, it had a 4.57 gear with the original D.L. so I knew that old 429SCJ had seen some "turns" in the past and once we did about 6 chassis pulls to 5500rpm, I told Jeff "good enough", this is matching number drag pack car and I am not going to risk it any further...............

It was a good time, after the first/original dyno-pull session, The "Big Kahuna" was attached to me for my 71 429SCJ pulling ahead in the HP tests against those other formidable Mustangs, and the 2nd feature, Dyno-Tuning for Power" reinforced the "Kahuna" thing with a clean/crisp pull in the end.............But to be honest, that 1970 BOSS 429 could have used a little bit of Holley work also, and I mentioned to Jeff, that I had all of the parts to tweak it, all we need is this dyno, but the owner seemed uninterested so we did not mention it.........It was a BEAUTIFUL example of a restored Grabber Blue 1970 BOSS 429 and standing outside of that car when it was on the dyno pulling to 5500 or so!!......WHAT A FRICKIN HOSS!! and wayyyyy nicer than my Joe Lunchbox 1971 SCJ Mach 1........

R
 

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I may be out in right field all on my own here, but to me the 71 Mustang in general is one of the ugliest mustangs ever produced right behind the Mustang II. I'd take a 4-eye fox body over a 71 any day of the week.
I also really like the looks of the SN95 and the S550 so my tastes are weird to be sure.
We think a lot alike Kyle.
 

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Yes, and one would have to "assume" that this practice was done across the board and not just to the version of Mustang that a person doesn't like..........meaning, a 375HP 429 puts down better numbers than a 335HP 428 (both Drag Pack cars) in magazine tests from two different years, let's say 1970 and 1971, or it could be a CJ comparo, 370HP 429 and 335HP 428.............You would have to "assume" that Ford provided a "prime sample" in 1970 for testing and also a "prime sample" for testing in 1971............and the same magazines tested both, possibly even the same magazine editor(s), and the numbers were documented as they were posted.........

..................and then the whole "under rated from the factory" thing...........If one is "claimed" to be under rated, then you would have to assume that all were under rated, not just the personal preference car........

Back in the 1999-2001 time period Mustang Monthly did a 6 Mustang "Big Block Blowout" feature, 3 Mustangs were chassis dynoed here in Lakeland Florida same day, same dyno, same big fan blowing across the "open hood" cars. 1 - 1970 Grabber Blue Boss 429, 1 - 1967 390 GTA and my 1971 429 SCJ. A few weeks before in Georgia, 1 -1967 Shelby 428PI, 1 - 1968 Shelby 428CJ and 1 - 1969 Shelby 428CJ..............All cars had to either be restored or original drive train with no headers, smog pumps in place factory dual or single point dist., factory as possible cams, etc...............My car put down the best numbers at 248rwhp and the BOSS 429 was right behind me.........The Shelby's in Georgia all put down numbers in the mid-230's to almost 240rwhp..........The GTA 390 C6 was below 200rwhp, and I will just leave it there.....Also the Shelby's had both 4spd. and C6 in the mix for testing.

The owner of the BOSS 429 was crying foul and kept wanting another pull.........mid way through the clean/crisp 3rd pull the upper hose blew off and sprayed antifreeze all over his restored engine compartment and windshield and even on the roof paint, I grabbed towels and started to clean, quickly clean........The owner was saying something was the matter with the dyno.......and me? I had no idea, it was my first experience on a chassis dyno and it was a weird feeling AND 250ish rwhp Horsepower out of a "375HP" 429 Super Cobra Jet was kinda disappointing I will admit.......

So the magazine editor (Jeff Ford) who had overseen these three pulls as well as the pulls in Georgia to verify each pull for authenticity asked me if I knew that my car was running rich........like "real rich" as it pulled through the rpm range?.........I told him I have been trying to get the car to run right (clean up) with it's 1971 Ford Shop Manual listed 71 pri. jets and 83 sec. jets in the oem D1Z Holley 780, but could not get the car to not "Black smoke"............and I REALLY did not understand why, I am sure it did not act that way from Ford........So in the end, we did another Magazine feature called "Dyno Tuning for Power" in maybe 2001?......On a portable dyno in Lakeland Florida in the back grassy lot of the Mustang Monthly office. We spent the better part of an afternoon tweaking that D1Z 780 Holley to attempt to achieve nice clean/crisp dyno runs like the other Mustangs/Shelby's did in that previous dyno feature.................FINALLY, after many Holley bowl drains and re-jetting and secondary spring changes to lessen or increase the opening I ended up with 70 pri. and 76 sec. jets (down in the rear from the factory 83's) and the car picked up about 50rwhp and was just under 300rwhp........I could have tweaked it more but I was done, that engine had never been apart/restored, it showed 31K original miles and it currently had an original 4.11 Ford gear installed, when I bought it, it had a 4.57 gear with the original D.L. so I knew that old 429SCJ had seen some "turns" in the past and once we did about 6 chassis pulls to 5500rpm, I told Jeff "good enough", this is matching number drag pack car and I am not going to risk it any further...............

It was a good time, after the first/original dyno-pull session, The "Big Kahuna" was attached to me for my 71 429SCJ pulling ahead in the HP tests against those other formidable Mustangs, and the 2nd feature, Dyno-Tuning for Power" reinforced the "Kahuna" thing with a clean/crisp pull in the end.............But to be honest, that 1970 BOSS 429 could have used a little bit of Holley work also, and I mentioned to Jeff, that I had all of the parts to tweak it, all we need is this dyno, but the owner seemed uninterested so we did not mention it.........It was a BEAUTIFUL example of a restored Grabber Blue 1970 BOSS 429 and standing outside of that car when it was on the dyno pulling to 5500 or so!!......WHAT A FRICKIN HOSS!! and wayyyyy nicer than my Joe Lunchbox 1971 SCJ Mach 1........

R
My general recollection of that dyno shootout, was that it was less illustrative of providing a valid comparison between engines, and more illustrative of how "out of tune" and totally out-of-whack so many restored cars are out there. It really didn't draw any clean winner, just plenty of cars that weren't pulling what they should. And FWIW, my 27K original-mile 1967 S-code 390 would make your jaw drop. Never been apart, never been fiddled-with, and it is dialed-in to the nth degree, like a sewing machine. It ROCKS, it would knock your socks off. Definitely good for 220hp++ at the rear wheels. Those 390's get a bad rap, because again, so many out there are totally out of the sweet-zone with the timing, advance, dwell, and carb. I've taken rides in other peoples cars, and had to bite my tongue..

Also Robert, don't conflate old gross horsepower ratings with modern sae-net dyno rear-wheel ratings. 375 gross is something more like 310-325 net (at best), so 290-300 at the wheels wouldn't be unusual. In fact, that'd be pretty strong, indicating that 375 was a bit conservative..

Also, the 335 rating for the 428CJ truly was Ford "bullshitting", with the specific intension of stacking the deck in their favor for NHRA classification with the 50 original 1968 1/2 CJ cars. A well-tuned 428CJ is very close to a well-tuned 429CJ. Both were under-rated from the factory, but the 428 was under-rated by a MILE, whereas the 429 only by a city block. It was not a steady/predictable thing with those damn ratings. The factory ratings were just about as crazy and varied as the old road tests were.
 

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Never drove a boss 429. Found one in Long Beach California when I was in high school. Was $500. Had the cash on me but ignorant about mechanical issues. Brought my dad with me to look at it who was an awesome mechanic. I checked the numbers and was an actual boss 429! My wood wouldn’t stop!!!! But he reached under it and proceeded to peel have the underside off from rust. Back then never did body or paint. But he said if I bought it and drove it home he run me over following me home as soon as I hit a bump, passed on it. Wish I could revisit that decision more that I have some abilities. But, I did have a 69 Mach1 with a 351 with a 4 speed hurst shifter. Man that car could handle compared to my 68 fastback. Wish I still had that car but gave it to my brother who sold it…. The things we regret… that car was insanely fun. And now what the aftermarket does with 351 Windsor’s. Mmmm. But I’m going with a stroker for my 68 one I start on its restoration. Can’t wait!!!!!
 
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Ford also had some other stuff like a 1 3/8" spline on the BB 4 speed top loader as opposed to the 1 1/16" spine on the SB 4 speed top loader. They made a 9 3/8" removable 3rd member that would not fit in the 9" housing without modification. They also pondered, and I believe they built at least 1, a Hone-o-Drive 2 speed diff that had attached to the front of the 3rd member on the Cougar Eliminator with a lever in the cockpit to change gears ratios say from 3.50 to 4.30. It was never an option though. Too bad IMO.

I remember when the 351C came out in 1970 and all the Chevy guys were crying and complaining to NHRA because they could not catch the high revving, high output power that the 351C made. They bitched and hollered and cried so loud that NHRA penalized the 351C drivers by .1-.2 lbs. per horsepower in the professional catagories. Chevy didn't like the fact that Ford had and engine that their SB couldn't touch.
I remember the Hone-o-Drives, I think the power and torque capabilities from that day were many times in question as it relates to durability..........

Also, the CJ/SCJ C6 got the cast iron tail shaft housing vs. the alum. tail shaft housing on the other lesser HP C6 transmission applications........

R
 

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Magazine test results (0-60 and 1/4 mile times) were such a mixed bag of unscientific nonsense back in the day, that you simply can't point to published tests and really determine anything whatsoever. A Boss 351 performing slightly better than a 428CJ could simply be a matter of cooler/drier weather at a better hooking lower-altitude track. They did not correct their numbers for anything, as has been done for the last 40 years.

I've driven them all, I agree with Robert that the 1971 429SCJ is a formidable runner (probably stronger than Boss 351), and I'd also put out there that the Boss 429 has always been the victim of "urban myth", being accused of being a dog. That was never really the case. The Boss 429 was indeed detuned from the factory, smallish carb, smallish cam and restrictive exhausts manifolds. But lurking within were the makings for an exotic monster that none of the other engines we're discussing could ever hope to match. Buy all of these vehicles brand-new, and then start modding, you'll quickly realize that the Boss 429 gets crazy-powerful at an exponential rate compared to the others. In any case, a bone-stock Boss 429 is a 13.70's-13.80's machine, maybe quicker at the right track. The Boss 351 was never appreciably (if at all) faster than the Boss 429, but there are no good/valid track tests from back in the day to point to. Just rhetoric and rumor and the occasional Boss Nine at a humid track in a terrible state of tune and a horrific driver, only helping to further the misinformation about the car.

Peter Klute, many moons ago, did a GREAT "shootout" of bone-stock muscle cars. He knew they were stock, because they were all restored in his shop. It was about as equal a setting as you could hope for, all cars in proper tune at the same track on the same day running in the same weather. You'll be surprised what comes out on top. And I apologize in advance for the young dork in the NPD shirt... ;)

That was great. Of course a '69 B9 is my dream Gen I Muscle car.
 

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I am into boats too. Well Ford powered boats to be exact.

my boat rigging mentor (30 years ago) was an retired K-boat racer. He raced the 7-Litre class so it was strictly stock bore/stroke 427's (Chev & Ford) 426 Hemi's and my friend Drew with the only 429 Boss.

This was before roller valvetrains, cheater strokers etc, All N/A but no limits on compression, carburetors or early fuel injection. Everyone ran open headers.

Drew bought all his parts from Holman & Moody. He preferred 2 double pumper Holleys on top of a Weiand Tunnel ram as most of the other competitors did.

He dominated.

He never lost a race. Yes he could drive better than most, maybe all but he won on an enormous horsepower advantage. He could just pull away from anyone who got close.

After 5-straight Championships, he retired.

Then he started hearing rumors that he was a cheater and got really angry. 4 years after he retired, He pulled out his same ole' boat and took 2 more consecutive championships. He built his own engines in his garage and was up against teams with multiple boats, driver's and sponsors.

Now they started pulling his engines apart after races, convinced he was cheating. Never found one single infraction.

After his second championship out of retirement the APBA simply just outlawed the B9 in circle boat and racing and that was that.
 

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I remember the Hone-o-Drives, I think the power and torque capabilities from that day were many times in question as it relates to durability..........

Also, the CJ/SCJ C6 got the cast iron tail shaft housing vs. the alum. tail shaft housing on the other lesser HP C6 transmission applications........

R
The big drawback on the Hone-oDrive was that it was only rated for 500 HP. I believe it was BHP.
 

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My general recollection of that dyno shootout, was that it was less illustrative of providing a valid comparison between engines, and more illustrative of how "out of tune" and totally out-of-whack so many restored cars are out there. It really didn't draw any clean winner, just plenty of cars that weren't pulling what they should. And FWIW, my 27K original-mile 1967 S-code 390 would make your jaw drop. Never been apart, never been fiddled-with, and it is dialed-in to the nth degree, like a sewing machine. It ROCKS, it would knock your socks off. Definitely good for 220hp++ at the rear wheels. Those 390's get a bad rap, because again, so many out there are totally out of the sweet-zone with the timing, advance, dwell, and carb. I've taken rides in other peoples cars, and had to bite my tongue..

Also Robert, don't conflate old gross horsepower ratings with modern sae-net dyno rear-wheel ratings. 375 gross is something more like 310-325 net (at best), so 290-300 at the wheels wouldn't be unusual. In fact, that'd be pretty strong, indicating that 375 was a bit conservative..

Also, the 335 rating for the 428CJ truly was Ford "bullshitting", with the specific intension of stacking the deck in their favor for NHRA classification with the 50 original 1968 1/2 CJ cars. A well-tuned 428CJ is very close to a well-tuned 429CJ. Both were under-rated from the factory, but the 428 was under-rated by a MILE, whereas the 429 only by a city block. It was not a steady/predictable thing with those damn ratings. The factory ratings were just about as crazy and varied as the old road tests were.
Yes, I too had questions about the 428PI and CJ tests in Georgia. I remember at least one of the CJ's said that their engine had been restored to oem Ford specs and then dyno'ed and tweaked on the dyno for best numbers, then installed in the car, and it may have been both CJ's that got that treatment. <<If this was the case, there should have been no "out of tune" issues. Then there was the 428PI, if I remember correctly they were dual quad and 360HP? <<I don't remember for sure........and then among those 428 cars there was a C6...........BUT ALL cars chassis dyno'ed in a very close HP range...........within just a few HP.

Generally, and this could be wrong and a very generic overview, but most people "back in the day" would claim a 75hp loss between the flywheel and the tires on a manual trans. car and 100hp loss for an automatic, this would be the big automatic transmissions, C6, TH400 etc.. <<<<Very general I know and chassis dynos were not as prevalent to verify this on street fuel available at the time, but that was the thought back then...............These 428 cars were very close with relatively no difference between manual and auto at the rear wheels and no real difference in the PI?.........

R
 

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Ford also had some other stuff like a 1 3/8" spline on the BB 4 speed top loader as opposed to the 1 1/16" spine on the SB 4 speed top loader. They made a 9 3/8" removable 3rd member that would not fit in the 9" housing without modification. They also pondered, and I believe they built at least 1, a Hone-o-Drive 2 speed diff that had attached to the front of the 3rd member on the Cougar Eliminator with a lever in the cockpit to change gears ratios say from 3.50 to 4.30. It was never an option though. Too bad IMO.

I remember when the 351C came out in 1970 and all the Chevy guys were crying and complaining to NHRA because they could not catch the high revving, high output power that the 351C made. They bitched and hollered and cried so loud that NHRA penalized the 351C drivers by .1-.2 lbs. per horsepower in the professional catagories. Chevy didn't like the fact that Ford had and engine that their SB couldn't touch.
This discussion is jarring loose old dead brain cells.................In addition to the cast iron tail shaft on the CJ C6, didn't it also get an extra friction disc and separator plate inside one or more of the drums?.........and if I remember correctly the drum(s) was/were machined uniquely for that extra disc/plate?

R
 

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I am into boats too. Well Ford powered boats to be exact.

my boat rigging mentor (30 years ago) was an retired K-boat racer. He raced the 7-Litre class so it was strictly stock bore/stroke 427's (Chev & Ford) 426 Hemi's and my friend Drew with the only 429 Boss.

This was before roller valvetrains, cheater strokers etc, All N/A but no limits on compression, carburetors or early fuel injection. Everyone ran open headers.

Drew bought all his parts from Holman & Moody. He preferred 2 double pumper Holleys on top of a Weiand Tunnel ram as most of the other competitors did.

He dominated.

He never lost a race. Yes he could drive better than most, maybe all but he won on an enormous horsepower advantage. He could just pull away from anyone who got close.

After 5-straight Championships, he retired.

Then he started hearing rumors that he was a cheater and got really angry. 4 years after he retired, He pulled out his same ole' boat and took 2 more consecutive championships. He built his own engines in his garage and was up against teams with multiple boats, driver's and sponsors.

Now they started pulling his engines apart after races, convinced he was cheating. Never found one single infraction.

After his second championship out of retirement the APBA simply just outlawed the B9 in circle boat and racing and that was that.
What a great story!! And it reinforces my assertion that the Boss 429 got a bad rap... It wasn't so much about how it ran driving it off the dealer lot (as you could see in the video I posted, it ran pretty darned good), it was the POTENTIAL that you just drove off the lot with, if you were willing to purchase a few parts, spin a few wrenches, and allow those beautiful heads to breath.

My Boss 429 still has its original engine, but it's not original internally. It was performance-built by Earl Wade in the early 1980's. Earl was best known for being Dyno Don Nicholson's crew chief and engine builder. 494 stroker, built to the moon, topped off with a 850cfm Holley that originally belonged to a 1968 L88 Corvette (probably a take-off carb at Earl's shop). When I purchased the car in 1997, it had giant long-tube headers running through 3" exhaust and 2-chamber flowmasters. If I started it in the garage, dishes would rattle in my kitchen LOL. And it was fast. I waged a "from a roll" race against my own 506hp S351 supercharged Saleen (friend was driving my Saleen), and the Boss just walked away from it, N/A... Keep in mind that 506hp back in the gross hp Boss days would've been well over 600, and the Boss laughed at it.

But the car was so damn loud. And whenever I carried a passenger, if we hit a dip in the road, the headers would crash violently against the pavement. I feared that I might crack or damage one of those aluminum Boss heads. So I put factory manifolds back on it, and factory exhaust, and.... It absolutely neutered the car 2500rpm-up. You can only blow so much air through a straw. But it still has enough low end grunt to pull a freight train out of the mud LOL, and that's still fun to play with ;) .

Robert, Jeff Ford was riding shotgun with me back in the days when the Boss was running the big exhaust. I powershifted from 2nd-3rd, polyglasses spinning in a haze, and all of a sudden "POP!!", and I came off the gas, and I had lost a cylinder, and there was an unholy racket coming from under the hood. It was still barely running, and we limped it back into the shop. And I walked away, we went out for drinks, because I couldn't bring myself to begin figuring out what I had done. The following Monday, I figured it out. It blew the packing out from between the fitting and the core of my #3 plug, such that compression was blowing-out the circumference.

Scared the PISS out of us!! You should have seen the look on our faces when it happened! And it was just a plug, nothing else. We laugh about that to this very day. I've kept the plug on my desk all these years. You can freely slide the core back and forth 3/8" within the fitting.
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What a great story!! And it reinforces my assertion that the Boss 429 got a bad rap... It wasn't so much about how it ran driving it off the dealer lot (as you could see in the video I posted, it ran pretty darned good), it was the POTENTIAL that you just drove off the lot with, if you were willing to purchase a few parts, spin a few wrenches, and allow those beautiful heads to breath.

My Boss 429 still has its original engine, but it's not original internally. It was performance-built by Earl Wade in the early 1980's. Earl was best known for being Dyno Don Nicholson's crew chief and engine builder. 494 stroker, built to the moon, topped off with a 850cfm Holley that originally belonged to a 1968 L88 Corvette (probably a take-off carb at Earl's shop). When I purchased the car in 1997, it had giant long-tube headers running through 3" exhaust and 2-chamber flowmasters. If I started it in the garage, dishes would rattle in my kitchen LOL. And it was fast. I waged a "from a roll" race against my own 506hp S351 supercharged Saleen (friend was driving my Saleen), and the Boss just walked away from it, N/A... Keep in mind that 506hp back in the gross hp Boss days would've been well over 600, and the Boss laughed at it.

But the car was so damn loud. And whenever I carried a passenger, if we hit a dip in the road, the headers would crash violently against the pavement. I feared that I might crack or damage one of those aluminum Boss heads. So I put factory manifolds back on it, and factory exhaust, and.... It absolutely neutered the car 2500rpm-up. You can only blow so much air through a straw. But it still has enough low end grunt to pull a freight train out of the mud LOL, and that's still fun to play with ;) .

Robert, Jeff Ford was riding shotgun with me back in the days when the Boss was running the big exhaust. I powershifted from 2nd-3rd, polyglasses spinning in a haze, and all of a sudden "POP!!", and I came off the gas, and I had lost a cylinder, and there was an unholy racket coming from under the hood. It was still barely running, and we limped it back into the shop. And I walked away, we went out for drinks, because I couldn't bring myself to begin figuring out what I had done. The following Monday, I figured it out. It blew the packing out from between the fitting and the core of my #3 plug, such that compression was blowing-out the circumference.

Scared the PISS out of us!! You should have seen the look on our faces when it happened! And it was just a plug, nothing else. We laugh about that to this very day. I've kept the plug on my desk all these years. You can freely slide the core back and forth 3/8" within the fitting. View attachment 222168 View attachment 222169
Rick - I remember the time you handed me the keys to that Black BOSS 429 and I drove it from NPD to Silver Springs for the show/display around the NPD area, it was intimidating, a Man Car to handle, but also fun.......It was like my 429 SCJ Mach 1 except on steroids!! Bigger HP, Bigger gear, Wilder Ride (if you wanted it to be, but I was not going there)..........Much more "announcing its presents".........It was a Very Cool experience.

Also, as I left NPD for the show that morning, shortly down the service road I noticed the hood fluttering. When we got to the end of the service road I pulled to the side and found that the hood was not completely closed (on the secondary/safety latch), so I shut it completely and turned right on US40 toward Silver Springs. By then, the parade of NPD cars had passed and I finally caught up to the pack and was behind a Galaxie if i remember correctly...............Cool memory for sure!!

R
 

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Then there was the 428PI, if I remember correctly they were dual quad and 360HP? <<I don't remember for sure........and
R
All 428CI engines had a dual plane intake manifold with a single 4 BBL carb rated at 735 CFM. The 428PI was the exception in that it had an aluminum intake manifold with the same 735 CFM carb. That was the only difference and yes it was rated at 360 BHP.
 

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This discussion is jarring loose old dead brain cells.................In addition to the cast iron tail shaft on the CJ C6, didn't it also get an extra friction disc and separator plate inside one or more of the drums?.........and if I remember correctly the drum(s) was/were machined uniquely for that extra disc/plate?

R
Not sure about this Robert.
 

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All 428CI engines had a dual plane intake manifold with a single 4 BBL carb rated at 735 CFM. The 428PI was the exception in that it had an aluminum intake manifold with the same 735 CFM carb. That was the only difference and yes it was rated at 360 BHP.
1967 GT500's had a dual-4V 428PI, I think that's what Robert's referring to.
 

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1967 GT500's had a dual-4V 428PI, I think that's what Robert's referring to.
Could be and yes only the '67 Shelby GT500 with the 428CI engine had the dual quads which was rated at 390 BHP.
 

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I just looked to verify what I was thinking........the internet says 355hp for the 1967 GT500 428 w/420 torque, I was thinking 360........but I do not see 390hp anywhere.....

R
 

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I just looked to verify what I was thinking........the internet says 355hp for the 1967 GT500 428 w/420 torque, I was thinking 360........but I do not see 390hp anywhere.....

R
The 1967 Shelby GT500 was the only year that had 2 offerings for the 428CI engine, one of which was the 355 BHP/420 TQ version with a single 4 BBL and the other was the 390 BHP/465 TQ version with dual 4 BBL's.
 
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