Concrete evidence of blown engine on boost?
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Weird that people still refuse to believe this car can handle boost when poth procharger and that turbo company have threads here with very detailed info on their REAL life experiances with FI on this engine. If the pistons were so horrible, much much cheaper than any previous Mustang EVER! I doubt very much any company would hassle with trying to make a super charger or turbo for it.
If a 10.1:1 compression aluminum 4 banger built by Honda can handle 8-9psi reliably why can't this 9.8:1 V-8 handle 6-8psi?
If a 10.1:1 compression aluminum 4 banger built by Honda can handle 8-9psi reliably why can't this 9.8:1 V-8 handle 6-8psi?
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Originally posted by nynvolt@March 5, 2005, 9:18 AM
Weird that people still refuse to believe this car can handle boost when poth procharger and that turbo company have threads here with very detailed info on their REAL life experiances with FI on this engine. If the pistons were so horrible, much much cheaper than any previous Mustang EVER! I doubt very much any company would hassle with trying to make a super charger or turbo for it.
If a 10.1:1 compression aluminum 4 banger built by Honda can handle 8-9psi reliably why can't this 9.8:1 V-8 handle 6-8psi?
Weird that people still refuse to believe this car can handle boost when poth procharger and that turbo company have threads here with very detailed info on their REAL life experiances with FI on this engine. If the pistons were so horrible, much much cheaper than any previous Mustang EVER! I doubt very much any company would hassle with trying to make a super charger or turbo for it.
If a 10.1:1 compression aluminum 4 banger built by Honda can handle 8-9psi reliably why can't this 9.8:1 V-8 handle 6-8psi?
Look to see what kind of pistons are in that Honda 4 banger you are talking about.
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From: New Carlisle, Ohio (20 miles north of Dayton)
Originally posted by nynvolt@March 5, 2005, 9:18 AM
Weird that people still refuse to believe this car can handle boost when poth procharger and that turbo company have threads here with very detailed info on their REAL life experiances with FI on this engine. If the pistons were so horrible, much much cheaper than any previous Mustang EVER! I doubt very much any company would hassle with trying to make a super charger or turbo for it.
If a 10.1:1 compression aluminum 4 banger built by Honda can handle 8-9psi reliably why can't this 9.8:1 V-8 handle 6-8psi?
Weird that people still refuse to believe this car can handle boost when poth procharger and that turbo company have threads here with very detailed info on their REAL life experiances with FI on this engine. If the pistons were so horrible, much much cheaper than any previous Mustang EVER! I doubt very much any company would hassle with trying to make a super charger or turbo for it.
If a 10.1:1 compression aluminum 4 banger built by Honda can handle 8-9psi reliably why can't this 9.8:1 V-8 handle 6-8psi?
Nynvolt,
I am not sure what your engine building experience is and PLEASE don't think I am talking down to you or anyone else. I may just be a little older than most of you and have had more time in my life to make dumb mistakes. I have personally put 3 supercharger engines together in the last 10 years. The 1st one was the stock 96 Cobra that blew. The next two are still running on 8 lbs of boost with no problems with forged components. In the first place a good blower motor should start with a 8.5/1 compression ratio not 10/1. The forged components can take the forces of detontion that will happen due too poor fuel or bad tune at WOT. And as far as these manufactures selling systems, why not if they have buyers. They are not telling you you can't damage you engine. I wish I could post my Kennebell manuals. He repeatedly warns the customer about the dangers of detontion and the resulting severe engine damage that can occur. This warning is repeated many times in his installation manuals. As far as the Honda goes I have no knowledge about them. Maybe they already have forged parts. The bottom line supercharging any engine increased cylinder pressures. The more boost the higher the pressures. The 1st component to see this pressure is the top of the pistons. BTW 6 lbs of boost is good for about 75 horsepower. Trust me its worth the cost.
70Mach1Owner
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Since we're talking about Hondas, it should be pointed out that they are not bulletproof either. The H22 Prelude motors are notorious for weak ringlands, and whaddaya know, the experienced Honda guys say NEVER boost a 'Lude past 6 psi on stock pistons.
I'm not arguing that the '05's are or are not boostable, I just wanted to point out that the piston design is apparently different from the earlier 4.6's.
I'm not arguing that the '05's are or are not boostable, I just wanted to point out that the piston design is apparently different from the earlier 4.6's.
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From: SandyEggo
Just got off the phone with JBA. They did an article last month in Hot Rod with the Vortech equipped auto. It will be on the stands in about three months. Anyway, a guy from SCT did the tuning, but wasn't comfortable with the auto because of the "throttle by wire." At 5800 rpm, they got 404 RWHP and 383 TQ. That was at 9.9 lbs of boost. He said that equates to about 540 FWHP. They were so uncomfortable with it, they removed it from the customers car until they develop the right program for the auto.
He said he's the 05's should be o.k. with up to 10 lbs of boost. That's with everything being perfect. I'm thinking 8 lbs, would be very o.k. Depending on the which SC you go with, an install can run from $1,500 to $2,500.
He said he's the 05's should be o.k. with up to 10 lbs of boost. That's with everything being perfect. I'm thinking 8 lbs, would be very o.k. Depending on the which SC you go with, an install can run from $1,500 to $2,500.
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I realize that applying any logic whatsoever to the auto industry is kind of :crazy: but here goes just a little ... since all the ford street legal s/c's are 6 psi then it would seem that boost up to that point would be fine for these engines. Granted what was done in the past doesnt mean much for the future or present but its something.
Also, the guy from procharger (Freeman?) has a new thread about the procharger times and he says the car is running at 8 psi on a stock engine ... for whatever that maybe worth ... here is to hoping that it will handle the 8 pounds (or more).
Also, the guy from procharger (Freeman?) has a new thread about the procharger times and he says the car is running at 8 psi on a stock engine ... for whatever that maybe worth ... here is to hoping that it will handle the 8 pounds (or more).
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The 10.1:1 was just and example because many have said the compression on the 3V was too high for boost, which ideally if you built it from the ground up it is. Any motor will blow if not tuned right and too much boost is aplied, no argument there. Just been way too much of the "anything over 4psi will be a bomb" on the net about these engines.
I have zero engine building experiance, unless you consider helping my dad when I was a kid by handing him the tools and getting his beer.
The Honda motors are generally boosted to around 4-6psi without any engine building at all.
Sorry to sound defensive, just growing tired of people espousing internet rumor as fact about this specific motor.
I have zero engine building experiance, unless you consider helping my dad when I was a kid by handing him the tools and getting his beer.
The Honda motors are generally boosted to around 4-6psi without any engine building at all.Sorry to sound defensive, just growing tired of people espousing internet rumor as fact about this specific motor.
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Originally posted by nynvolt@March 5, 2005, 7:17 PM
The 10.1:1 was just and example because many have said the compression on the 3V was too high for boost, which ideally if you built it from the ground up it is. Any motor will blow if not tuned right and too much boost is aplied, no argument there. Just been way too much of the "anything over 4psi will be a bomb" on the net about these engines.
I have zero engine building experiance, unless you consider helping my dad when I was a kid by handing him the tools and getting his beer. The Honda motors are generally boosted to around 4-6psi without any engine building at all.
Sorry to sound defensive, just growing tired of people espousing internet rumor as fact about this specific motor.
The 10.1:1 was just and example because many have said the compression on the 3V was too high for boost, which ideally if you built it from the ground up it is. Any motor will blow if not tuned right and too much boost is aplied, no argument there. Just been way too much of the "anything over 4psi will be a bomb" on the net about these engines.
I have zero engine building experiance, unless you consider helping my dad when I was a kid by handing him the tools and getting his beer.
The Honda motors are generally boosted to around 4-6psi without any engine building at all.Sorry to sound defensive, just growing tired of people espousing internet rumor as fact about this specific motor.
Nynvolt,
Absolutley no offense taken. Just tring to help. I want all stangers to get all the horsepower they are looking for. But I want it to be safe power. I sit and read the rumors and unfounded accusations about alot of topics on this site but keep my mouth shut about alot of it because I may not have any personal experience to share, just opinions. We all know what they say about opinions. I have real world experiences to share on this topic. For what its worth, if I where to look at putting another blower on a stang I would not puchase another one unless it had some sort of intercooler like the Whipple or Procharger. It is the pistons that are the weakest point in all 4.6 engines regardless of the model year. But it is the detonation that occurs from supercharging that will kill ANY engines if it occurs to much. Intercooling will help alot to prevent detonation. The other hint I would give is problably the hardest for any motorhead to follow. DON'T GET GREEDY!!! Keep the boost respectable on a stock motor. Trust me it only takes a few seconds of bad judgement to harm you engine. Best of luck to you.
70Mach1Owner
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Great thread with lots of good info! One point I would like to make is that the tune is more important than psi (up to reasonable levels). You can have a poor tune with 4 psi and you will blow your engine. You can have a great tune with 10psi and have a happy engine life. True, cylinder pressures play a role, but prevention of detonation is more important for these engines (as is limiting RPM).
There are plenty of stock turbo vehicles running comparitively high boost pressures, all without forged internals. My WRX runs about 14psi stock from the factory, but it comes with a tune that is pig rich to prevent detonation. It isn't what I'd call a great tune, but it is safe. There are great aftermarket tunes available that up the boost to 16-17psi without issue. Even with an 8:1 compression ration, those are some high cylinder pressures!
6psi is probably the safe limit for non-intercooled power adders on the Mustang. If you are going with a good intercooler, though, there is no reason why you can't up the boost a couple more psi as long as you have a good tune.
That said, it is true that we still don't seem to have a side by side comparison of the 2005 internals against the previous years. We really need this to put to rest all speculation. I wish some of the kit manufacturers (Kenne-Bell, Vortech, Whipple, etc...) would do this with some sort of a write-up if they have actually torn down these engines to really examine them.
There are plenty of stock turbo vehicles running comparitively high boost pressures, all without forged internals. My WRX runs about 14psi stock from the factory, but it comes with a tune that is pig rich to prevent detonation. It isn't what I'd call a great tune, but it is safe. There are great aftermarket tunes available that up the boost to 16-17psi without issue. Even with an 8:1 compression ration, those are some high cylinder pressures!
6psi is probably the safe limit for non-intercooled power adders on the Mustang. If you are going with a good intercooler, though, there is no reason why you can't up the boost a couple more psi as long as you have a good tune.
That said, it is true that we still don't seem to have a side by side comparison of the 2005 internals against the previous years. We really need this to put to rest all speculation. I wish some of the kit manufacturers (Kenne-Bell, Vortech, Whipple, etc...) would do this with some sort of a write-up if they have actually torn down these engines to really examine them.
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Originally posted by Import-Slaya@March 6, 2005, 7:18 AM
Great thread with lots of good info! One point I would like to make is that the tune is more important than psi (up to reasonable levels). You can have a poor tune with 4 psi and you will blow your engine. You can have a great tune with 10psi and have a happy engine life. True, cylinder pressures play a role, but prevention of detonation is more important for these engines (as is limiting RPM).
There are plenty of stock turbo vehicles running comparitively high boost pressures, all without forged internals. My WRX runs about 14psi stock from the factory, but it comes with a tune that is pig rich to prevent detonation. It isn't what I'd call a great tune, but it is safe. There are great aftermarket tunes available that up the boost to 16-17psi without issue. Even with an 8:1 compression ration, those are some high cylinder pressures!
6psi is probably the safe limit for non-intercooled power adders on the Mustang. If you are going with a good intercooler, though, there is no reason why you can't up the boost a couple more psi as long as you have a good tune.
That said, it is true that we still don't seem to have a side by side comparison of the 2005 internals against the previous years. We really need this to put to rest all speculation. I wish some of the kit manufacturers (Kenne-Bell, Vortech, Whipple, etc...) would do this with some sort of a write-up if they have actually torn down these engines to really examine them.
Great thread with lots of good info! One point I would like to make is that the tune is more important than psi (up to reasonable levels). You can have a poor tune with 4 psi and you will blow your engine. You can have a great tune with 10psi and have a happy engine life. True, cylinder pressures play a role, but prevention of detonation is more important for these engines (as is limiting RPM).
There are plenty of stock turbo vehicles running comparitively high boost pressures, all without forged internals. My WRX runs about 14psi stock from the factory, but it comes with a tune that is pig rich to prevent detonation. It isn't what I'd call a great tune, but it is safe. There are great aftermarket tunes available that up the boost to 16-17psi without issue. Even with an 8:1 compression ration, those are some high cylinder pressures!
6psi is probably the safe limit for non-intercooled power adders on the Mustang. If you are going with a good intercooler, though, there is no reason why you can't up the boost a couple more psi as long as you have a good tune.
That said, it is true that we still don't seem to have a side by side comparison of the 2005 internals against the previous years. We really need this to put to rest all speculation. I wish some of the kit manufacturers (Kenne-Bell, Vortech, Whipple, etc...) would do this with some sort of a write-up if they have actually torn down these engines to really examine them.
Import-Slaya
You make a very good point about RPM and Air fuel ratio. What happens with alot of these supercharger kits is at WOT they tend to go lean to the point that it enhances detontion. To keep the price of alot of the kits down and to make sure the vehicle can still pass emission tests the fuel system upgrades that are really needed for proper tune is not possible. These kit manufactures have to make sure they are still 50 states legal. Your WRX going pig rich is a good thing for engine safety. It knocks off a few ponies by will make detontion much less likely. In the installtion manuals from Kennebell on my 96 Cobra he warns about not taking the RPM above 6000 because the airfuel mixture goes way lean. It tough to remember that when you have a 7200 RPM redline. Kennbell knows the motor needs larger injectors to suppy the fuel required at the higher RPM but can't supply them in the kits because of the emission restrictions for non- boost running. It is like everthing else in life. A COMPROMISE. And all other street legal kits have the same limitations.
70MACH1OWNER
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And don't forget you are comparing apples to oranges when you look at these small 4 bangers. The diameter of the cylinder makes a HUGE difference in detonation resistance of an engine. Basically, the faster the flame front reaches are points in the chamber, the less time you have for detonation to occour. The flame propogation speed does not increase just because you have a larger cylinder, so you end up with more time for detonation to occour, and a higher probability that it WILL occour.
The short upshot is that a small cylinder is GENERALLY able to run higher cylinder pressures (either via static compression ratio or boost) before detonation is likely than a large cylinder. So those statements saying "but my Honda can run 10:1 and 8 psi with no issues, so the Mustang should be able to also..." are not quite on the mark. Ever notic how high the compression ratio is on the 600cc bikes?
The short upshot is that a small cylinder is GENERALLY able to run higher cylinder pressures (either via static compression ratio or boost) before detonation is likely than a large cylinder. So those statements saying "but my Honda can run 10:1 and 8 psi with no issues, so the Mustang should be able to also..." are not quite on the mark. Ever notic how high the compression ratio is on the 600cc bikes?
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Originally posted by 70MACH1OWNER@March 4, 2005, 5:02 PM
I personally believe that the Ford 4.6 is an awesome engine in its stock form and the Kennebell Superchargers are the best. Bottom line is never exceed 6 lbs of boost on a stock motor. And if you feel the need for speed then yank to motor and build it with forged stuff. It is also a must to run the best gas possible. 93 octane minimum.
What happens when you up the boost is the engine starts to detonate. At WOT it is like hitting the top of your pistons with a sledge hammer. The stock cast pistons and rods can't take it. One 1/4 mile run was all it took for mine. I should have been running 100 octane for that boost level but could not get it at the time. Bad decision on my part. And by the way the computer and the knock sensors cannot react fast enough to back the timing off when this detonation starts. I check my computer to see if it had any codes for detonation and it was clean. I learned the hard way as most of us do. Just be careful. If you search the net for 4.6 Mod Motor blow ups you will find it happens just like I decribed above. ALOT!!!!
70Mach1Owner
I personally believe that the Ford 4.6 is an awesome engine in its stock form and the Kennebell Superchargers are the best. Bottom line is never exceed 6 lbs of boost on a stock motor. And if you feel the need for speed then yank to motor and build it with forged stuff. It is also a must to run the best gas possible. 93 octane minimum.
What happens when you up the boost is the engine starts to detonate. At WOT it is like hitting the top of your pistons with a sledge hammer. The stock cast pistons and rods can't take it. One 1/4 mile run was all it took for mine. I should have been running 100 octane for that boost level but could not get it at the time. Bad decision on my part. And by the way the computer and the knock sensors cannot react fast enough to back the timing off when this detonation starts. I check my computer to see if it had any codes for detonation and it was clean. I learned the hard way as most of us do. Just be careful. If you search the net for 4.6 Mod Motor blow ups you will find it happens just like I decribed above. ALOT!!!!
70Mach1Owner
There are a lot of people out there running KB blowers at 9+ psi with proper tunes and no problems at all. I personally ran a Novi 2000 at 11psi with NO INTERCOOLER for over a year before I sold the car last August, and the current owner is still running the car at that boost level. With a very conservative tune I made 429rwhp/404rwtq. This was on 93 octane pump gas.
The 4.6L motor can handle 8-10psi of boost without any problem, IF THE TUNE IS CORRECT. If you get greedy on timing or don't get the A/F ratio right, you will grenade the motor.
I don't see any reason whatsoever the 3V motors will be any different.
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Originally posted by MrMorden+March 7, 2005, 8:47 AM--><div class='quotetop'>QUOTE(MrMorden @ March 7, 2005, 8:47 AM)</div><div class='quotemain'><!--QuoteBegin-70MACH1OWNER@March 4, 2005, 5:02 PM
I personally believe that the Ford 4.6 is an awesome engine in its stock form and the Kennebell Superchargers are the best. Bottom line is never exceed 6 lbs of boost on a stock motor. And if you feel the need for speed then yank to motor and build it with forged stuff. It is also a must to run the best gas possible. 93 octane minimum.
What happens when you up the boost is the engine starts to detonate. At WOT it is like hitting the top of your pistons with a sledge hammer. The stock cast pistons and rods can't take it. One 1/4 mile run was all it took for mine. I should have been running 100 octane for that boost level but could not get it at the time. Bad decision on my part. And by the way the computer and the knock sensors cannot react fast enough to back the timing off when this detonation starts. I check my computer to see if it had any codes for detonation and it was clean. I learned the hard way as most of us do. Just be careful. If you search the net for 4.6 Mod Motor blow ups you will find it happens just like I decribed above. ALOT!!!!
70Mach1Owner
I personally believe that the Ford 4.6 is an awesome engine in its stock form and the Kennebell Superchargers are the best. Bottom line is never exceed 6 lbs of boost on a stock motor. And if you feel the need for speed then yank to motor and build it with forged stuff. It is also a must to run the best gas possible. 93 octane minimum.
What happens when you up the boost is the engine starts to detonate. At WOT it is like hitting the top of your pistons with a sledge hammer. The stock cast pistons and rods can't take it. One 1/4 mile run was all it took for mine. I should have been running 100 octane for that boost level but could not get it at the time. Bad decision on my part. And by the way the computer and the knock sensors cannot react fast enough to back the timing off when this detonation starts. I check my computer to see if it had any codes for detonation and it was clean. I learned the hard way as most of us do. Just be careful. If you search the net for 4.6 Mod Motor blow ups you will find it happens just like I decribed above. ALOT!!!!
70Mach1Owner
There are a lot of people out there running KB blowers at 9+ psi with proper tunes and no problems at all. I personally ran a Novi 2000 at 11psi with NO INTERCOOLER for over a year before I sold the car last August, and the current owner is still running the car at that boost level. With a very conservative tune I made 429rwhp/404rwtq. This was on 93 octane pump gas.
The 4.6L motor can handle 8-10psi of boost without any problem, IF THE TUNE IS CORRECT. If you get greedy on timing or don't get the A/F ratio right, you will grenade the motor.
I don't see any reason whatsoever the 3V motors will be any different.
[/b][/quote]
Andy,
I completely agree with you. It was detonation that destroyed that motor. As far as it being in proper tune. All I can say I had installed everything that I was supposed to for that kit. It had a new chip for 8 lbs, I installed the boost-a-pump that Kennebell requires to increase fuel requirements. I admit to not running the 100 octane unleaded fuel that he required. The bottom line I agree that your tune had better be perfect. If you review my later posts on this thread I think you will see that all I am saying is that the pistons in these engines will not accept anything less than a perfect tune. Just a few seconds of detonation will destroy them. So that is why I suggest keeping the boost to 6 lbs to stay on the safe side. Forged conponents can simply take more of a pounding. Most of the people that install superchargers on their cars will do what the manufacture states and run it at WOT. They will not take it to a good tuner and have it checked out on the dyno to make sure everything is correct. If that tune or chip is not perfect than these engines can be damaged in just a few seconds.
70Mach1Owner
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Originally posted by 70MACH1OWNER@March 7, 2005, 1:56 PM
Andy,
I completely agree with you. It was detonation that destroyed that motor. As far as it being in proper tune. All I can say I had installed everything that I was supposed to for that kit. It had a new chip for 8 lbs, I installed the boost-a-pump that Kennebell requires to increase fuel requirements. I admit to not running the 100 octane unleaded fuel that he required. The bottom line I agree that your tune had better be perfect. If you review my later posts on this thread I think you will see that all I am saying is that the pistons in these engines will not accept anything less than a perfect tune. Just a few seconds of detonation will destroy them. So that is why I suggest keeping the boost to 6 lbs to stay on the safe side. Forged conponents can simply take more of a pounding. Most of the people that install superchargers on their cars will do what the manufacture states and run it at WOT. They will not take it to a good tuner and have it checked out on the dyno to make sure everything is correct. If that tune or chip is not perfect than these engines can be damaged in just a few seconds.
70Mach1Owner
Andy,
I completely agree with you. It was detonation that destroyed that motor. As far as it being in proper tune. All I can say I had installed everything that I was supposed to for that kit. It had a new chip for 8 lbs, I installed the boost-a-pump that Kennebell requires to increase fuel requirements. I admit to not running the 100 octane unleaded fuel that he required. The bottom line I agree that your tune had better be perfect. If you review my later posts on this thread I think you will see that all I am saying is that the pistons in these engines will not accept anything less than a perfect tune. Just a few seconds of detonation will destroy them. So that is why I suggest keeping the boost to 6 lbs to stay on the safe side. Forged conponents can simply take more of a pounding. Most of the people that install superchargers on their cars will do what the manufacture states and run it at WOT. They will not take it to a good tuner and have it checked out on the dyno to make sure everything is correct. If that tune or chip is not perfect than these engines can be damaged in just a few seconds.
70Mach1Owner
Was this an intercooled kit? Who recommended 100 octane gas, the tuner or Kenne Bell? Something doesn't seem quite right, because I know there are people out there running 10psi+ on premium pump gas with Kenne Bell kits...
You are 100% correct, it really only takes a second or two of detonation at high rpm to wreck a motor. timing should be kept conservative and the a/f nice and fat. I'd rather leave a few horsepower on the table than replace the motor.
Best of luck!
Andy
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Originally posted by MrMorden+March 7, 2005, 10:04 PM--><div class='quotetop'>QUOTE(MrMorden @ March 7, 2005, 10:04 PM)</div><div class='quotemain'><!--QuoteBegin-70MACH1OWNER@March 7, 2005, 1:56 PM
Andy,
I completely agree with you. It was detonation that destroyed that motor. As far as it being in proper tune. All I can say I had installed everything that I was supposed to for that kit. It had a new chip for 8 lbs, I installed the boost-a-pump that Kennebell requires to increase fuel requirements. I admit to not running the 100 octane unleaded fuel that he required. The bottom line I agree that your tune had better be perfect. If you review my later posts on this thread I think you will see that all I am saying is that the pistons in these engines will not accept anything less than a perfect tune. Just a few seconds of detonation will destroy them. So that is why I suggest keeping the boost to 6 lbs to stay on the safe side. Forged conponents can simply take more of a pounding. Most of the people that install superchargers on their cars will do what the manufacture states and run it at WOT. They will not take it to a good tuner and have it checked out on the dyno to make sure everything is correct. If that tune or chip is not perfect than these engines can be damaged in just a few seconds.
70Mach1Owner
Andy,
I completely agree with you. It was detonation that destroyed that motor. As far as it being in proper tune. All I can say I had installed everything that I was supposed to for that kit. It had a new chip for 8 lbs, I installed the boost-a-pump that Kennebell requires to increase fuel requirements. I admit to not running the 100 octane unleaded fuel that he required. The bottom line I agree that your tune had better be perfect. If you review my later posts on this thread I think you will see that all I am saying is that the pistons in these engines will not accept anything less than a perfect tune. Just a few seconds of detonation will destroy them. So that is why I suggest keeping the boost to 6 lbs to stay on the safe side. Forged conponents can simply take more of a pounding. Most of the people that install superchargers on their cars will do what the manufacture states and run it at WOT. They will not take it to a good tuner and have it checked out on the dyno to make sure everything is correct. If that tune or chip is not perfect than these engines can be damaged in just a few seconds.
70Mach1Owner
Was this an intercooled kit? Who recommended 100 octane gas, the tuner or Kenne Bell? Something doesn't seem quite right, because I know there are people out there running 10psi+ on premium pump gas with Kenne Bell kits...
You are 100% correct, it really only takes a second or two of detonation at high rpm to wreck a motor. timing should be kept conservative and the a/f nice and fat. I'd rather leave a few horsepower on the table than replace the motor.
Best of luck!
Andy
[/b][/quote]
Andy,
No it was not an intercooled kit. This was a 96 Cobra and Kennebell did not offer an intercooler at that time. It was Kennebell that suggested that on any kit of 8 lbs or more you needed to run 100 octane unleaded fuel. I don't know if that was over kill on his part or not. What you have to remember is that motor started at a 10.5 / 1 compression ratio. Thats starting awful high to put a blower on. For what it's worth I was running 94 octane plus 2 bottles of octane boost when mine blew. I don't know how they run 10 lbs or more today. They must pull out a bunch of timing to keep them alive.
70Mach1onwer
Bullitt Member
Joined: October 4, 2004
Posts: 238
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I see the issues now. 10.5 compression plus no intercooler...I forgot about the higher Cobra CR. My GT was running 9.4 CR, and that makes a big difference.
Plus the twin-screws make more heat than a centrifugal blower, so you definitely would have benefitted from an intercooler! And I can believe you needed race gas with that setup, absolutely.
The KB guys I know are running intercooled kits on GTs with 8.5-9.5 compression, or intecooled kits on 03/04 Cobras with all forged parts.
The GTs can go to 11psi, the Cobras to 14 or more...
Plus the twin-screws make more heat than a centrifugal blower, so you definitely would have benefitted from an intercooler! And I can believe you needed race gas with that setup, absolutely.
The KB guys I know are running intercooled kits on GTs with 8.5-9.5 compression, or intecooled kits on 03/04 Cobras with all forged parts.
The GTs can go to 11psi, the Cobras to 14 or more...
Bullitt Member
Joined: October 12, 2004
Posts: 312
Likes: 0
Its all about the tune and the knowledge of the driver.
Like any 4.6 of the past dont run it lean and dont bounce the rev limiter.
Just about any engine can handle a moderate amount of boost (under 8 pounds). But people always like to forcast the worst. (it will be the hottest summer ever, coldest winter, car cant be modified.) :lmao:
Like any 4.6 of the past dont run it lean and dont bounce the rev limiter.
Just about any engine can handle a moderate amount of boost (under 8 pounds). But people always like to forcast the worst. (it will be the hottest summer ever, coldest winter, car cant be modified.) :lmao:
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