Boost Limit on 4 bolt heads
heads retorqued mid season after a few track days...torqued 10% over spec by suggestion of an arp rep
Im not a big blower expert , i prefer big laggy turbos, but i know it takes crazy HP to spin a blower. We figured it took like 300ish hp to spin my buddys F1R at 7500rpm at the power it was making
. Also assumed if it took "300hp" to spin the blower to make 1000 wheel horsepower, the motor was affectivley seeing 1300ish HP. Give or take a few .Blown06 says it does not show at the crank. So he maybe right.and i guess it would not, but id assume the motor is still under the added stresses of the blower and the power its sucking up to spin. That power is going some were and i assume cylinder pressures show the 150 lost HP though its not measurable at the crank.
so the way you "guessed your HP level at the crank wasnt super crazy. Though id asssume its closer to 1200. Either way no one cares thats not the real problem 500 or 2000hp you got some issues. Lol
As much as i loveee the LSX plarform this is the reason i went back to a dart block SBC. To build a 2000hp capable LS like my SBC would cost almost twice as much.
lol its the internet man, people love bustin other peoples *****. Just be glad were not on yellowbullet.
Im not a big blower expert , i prefer big laggy turbos, but i know it takes crazy HP to spin a blower. We figured it took like 300ish hp to spin my buddys F1R at 7500rpm at the power it was making
. Also assumed if it took "300hp" to spin the blower to make 1000 wheel horsepower, the motor was affectivley seeing 1300ish HP. Give or take a few .Blown06 says it does not show at the crank. So he maybe right.and i guess it would not, but id assume the motor is still under the added stresses of the blower and the power its sucking up to spin. That power is going some were and i assume cylinder pressures show the 150 lost HP though its not measurable at the crank.
so the way you "guessed your HP level at the crank wasnt super crazy. Though id asssume its closer to 1200. Either way no one cares thats not the real problem 500 or 2000hp you got some issues. Lol
As much as i loveee the LSX plarform this is the reason i went back to a dart block SBC. To build a 2000hp capable LS like my SBC would cost almost twice as much.
Im not a big blower expert , i prefer big laggy turbos, but i know it takes crazy HP to spin a blower. We figured it took like 300ish hp to spin my buddys F1R at 7500rpm at the power it was making
. Also assumed if it took "300hp" to spin the blower to make 1000 wheel horsepower, the motor was affectivley seeing 1300ish HP. Give or take a few .Blown06 says it does not show at the crank. So he maybe right.and i guess it would not, but id assume the motor is still under the added stresses of the blower and the power its sucking up to spin. That power is going some were and i assume cylinder pressures show the 150 lost HP though its not measurable at the crank.
so the way you "guessed your HP level at the crank wasnt super crazy. Though id asssume its closer to 1200. Either way no one cares thats not the real problem 500 or 2000hp you got some issues. Lol
As much as i loveee the LSX plarform this is the reason i went back to a dart block SBC. To build a 2000hp capable LS like my SBC would cost almost twice as much.
id just keep running it. At this point theres not a whole lot i dont think you can do. It runs and runs fine, no overheating or over preassure in the cooling system. Didnt torch out a gasket, maybe pull some timing to be safe and keep makin some passes. Sounds like standard race car issues lol
I'm beginning to think all of these "it'll hold this much power" comments are based a lot on what turbo guys are doing and is not quiet accurate for the centri blower guys. I'm still learning this (at a very steep learning curve with my stuff), but I am seeing a trend here. The problem is that probably 95+% of the fairly serious power people are using turbos so most of the tuning information that is posted on the web is from that. Hell, I'm the only guy in the truck world using a procharger at these levels....as far as the internet goes.
If you compared fuel flow numbers between a centri blower setup and a turbo setup at the same rwhp level, the blower is going to show a significant amount more fuel flow. This is because it takes a ton more power to spin the blower. So while a blower combo might show 1000 at the tire, the internal parts of the engine are seeing significantly more than that (I've heard as much as 300+ hp to drive the f2 on my truck). My fuel flow numbers are off the charts compared to other turbo trucks trapping the same as mine. I blame this for blower cars not being able to put as much power to the ground as their turbo counterpart especially on 4-bolt heads.
With that said, C5mtl, I don't think there is anything necessarily wrong with your stuff. You're just at a limit with the parts you have in the current configuration.
While I'm certainly not doing anything earth shattering new in the procharger world, I am sort of pioneering this path in using a late model truck(heavy) and using 4-bolt heads. My current combo is an iron 408 with an F2 procharger with 245cc Edelbrock heads. I've certainly had my share of issues with pushing water trying to make this work. Check out this video if you haven't seen it yet. What your looking at is the camera angle pointed up to the top, pointing at the radiator cap. I was overloading the overflow line quite a bit.
Here are some pics of the block decks after I tore it down. You can see that the head gasket was compromised on at least 6 of the 8 holes. I don't have pics of the heads or the gaskets. The gaskets were cometics with ARP studs (stock size) torqued to 80lbs. The good thing is that it ran 8.99 at 154 mph at 4110lbs like this.
To address the issue, I'm currently making a number of changes to the cooling system to help ward off this issue. I'm doing a full fill on the block and dry decking the heads. Also making the move to 1/2" studs. I'm gonna reverse cool the heads only via -6 lines pointing directly at the back of the combustion chambers and pulling water out of the heads via -8 lines where the steam ports used to be. Here are some pics of the heads so far.
I don't post my progress on this site much as I have a build thread going on the truck site. If your trying to push a 4-bolt set up with a blower......or like the truck, you can follow along at
http://www.performancetrucks.net/for...h-more-463288/
Just trying to offer what information I have gathered so far. I'm a pretty die hard procharger guy and always enjoy seeing others succeed with centri blowers. Sorry for the long post. lol
If you compared fuel flow numbers between a centri blower setup and a turbo setup at the same rwhp level, the blower is going to show a significant amount more fuel flow. This is because it takes a ton more power to spin the blower. So while a blower combo might show 1000 at the tire, the internal parts of the engine are seeing significantly more than that (I've heard as much as 300+ hp to drive the f2 on my truck). My fuel flow numbers are off the charts compared to other turbo trucks trapping the same as mine. I blame this for blower cars not being able to put as much power to the ground as their turbo counterpart especially on 4-bolt heads.
With that said, C5mtl, I don't think there is anything necessarily wrong with your stuff. You're just at a limit with the parts you have in the current configuration.
While I'm certainly not doing anything earth shattering new in the procharger world, I am sort of pioneering this path in using a late model truck(heavy) and using 4-bolt heads. My current combo is an iron 408 with an F2 procharger with 245cc Edelbrock heads. I've certainly had my share of issues with pushing water trying to make this work. Check out this video if you haven't seen it yet. What your looking at is the camera angle pointed up to the top, pointing at the radiator cap. I was overloading the overflow line quite a bit.
Here are some pics of the block decks after I tore it down. You can see that the head gasket was compromised on at least 6 of the 8 holes. I don't have pics of the heads or the gaskets. The gaskets were cometics with ARP studs (stock size) torqued to 80lbs. The good thing is that it ran 8.99 at 154 mph at 4110lbs like this.
To address the issue, I'm currently making a number of changes to the cooling system to help ward off this issue. I'm doing a full fill on the block and dry decking the heads. Also making the move to 1/2" studs. I'm gonna reverse cool the heads only via -6 lines pointing directly at the back of the combustion chambers and pulling water out of the heads via -8 lines where the steam ports used to be. Here are some pics of the heads so far.
I don't post my progress on this site much as I have a build thread going on the truck site. If your trying to push a 4-bolt set up with a blower......or like the truck, you can follow along at
http://www.performancetrucks.net/for...h-more-463288/
Just trying to offer what information I have gathered so far. I'm a pretty die hard procharger guy and always enjoy seeing others succeed with centri blowers. Sorry for the long post. lol
I'm beginning to think all of these "it'll hold this much power" comments are based a lot on what turbo guys are doing and is not quiet accurate for the centri blower guys. I'm still learning this (at a very steep learning curve with my stuff), but I am seeing a trend here. The problem is that probably 95+% of the fairly serious power people are using turbos so most of the tuning information that is posted on the web is from that. Hell, I'm the only guy in the truck world using a procharger at these levels....as far as the internet goes.
If you compared fuel flow numbers between a centri blower setup and a turbo setup at the same rwhp level, the blower is going to show a significant amount more fuel flow. This is because it takes a ton more power to spin the blower. So while a blower combo might show 1000 at the tire, the internal parts of the engine are seeing significantly more than that (I've heard as much as 300+ hp to drive the f2 on my truck). My fuel flow numbers are off the charts compared to other turbo trucks trapping the same as mine. I blame this for blower cars not being able to put as much power to the ground as their turbo counterpart especially on 4-bolt heads.
With that said, C5mtl, I don't think there is anything necessarily wrong with your stuff. You're just at a limit with the parts you have in the current configuration.
While I'm certainly not doing anything earth shattering new in the procharger world, I am sort of pioneering this path in using a late model truck(heavy) and using 4-bolt heads. My current combo is an iron 408 with an F2 procharger with 245cc Edelbrock heads. I've certainly had my share of issues with pushing water trying to make this work. Check out this video if you haven't seen it yet. What your looking at is the camera angle pointed up to the top, pointing at the radiator cap. I was overloading the overflow line quite a bit.
Here are some pics of the block decks after I tore it down. You can see that the head gasket was compromised on at least 6 of the 8 holes. I don't have pics of the heads or the gaskets. The gaskets were cometics with ARP studs (stock size) torqued to 80lbs. The good thing is that it ran 8.99 at 154 mph at 4110lbs like this.
To address the issue, I'm currently making a number of changes to the cooling system to help ward off this issue. I'm doing a full fill on the block and dry decking the heads. Also making the move to 1/2" studs. I'm gonna reverse cool the heads only via -6 lines pointing directly at the back of the combustion chambers and pulling water out of the heads via -8 lines where the steam ports used to be. Here are some pics of the heads so far.
I don't post my progress on this site much as I have a build thread going on the truck site. If your trying to push a 4-bolt set up with a blower......or like the truck, you can follow along at
http://www.performancetrucks.net/for...h-more-463288/
Just trying to offer what information I have gathered so far. I'm a pretty die hard procharger guy and always enjoy seeing others succeed with centri blowers. Sorry for the long post. lol
If you compared fuel flow numbers between a centri blower setup and a turbo setup at the same rwhp level, the blower is going to show a significant amount more fuel flow. This is because it takes a ton more power to spin the blower. So while a blower combo might show 1000 at the tire, the internal parts of the engine are seeing significantly more than that (I've heard as much as 300+ hp to drive the f2 on my truck). My fuel flow numbers are off the charts compared to other turbo trucks trapping the same as mine. I blame this for blower cars not being able to put as much power to the ground as their turbo counterpart especially on 4-bolt heads.
With that said, C5mtl, I don't think there is anything necessarily wrong with your stuff. You're just at a limit with the parts you have in the current configuration.
While I'm certainly not doing anything earth shattering new in the procharger world, I am sort of pioneering this path in using a late model truck(heavy) and using 4-bolt heads. My current combo is an iron 408 with an F2 procharger with 245cc Edelbrock heads. I've certainly had my share of issues with pushing water trying to make this work. Check out this video if you haven't seen it yet. What your looking at is the camera angle pointed up to the top, pointing at the radiator cap. I was overloading the overflow line quite a bit.
Here are some pics of the block decks after I tore it down. You can see that the head gasket was compromised on at least 6 of the 8 holes. I don't have pics of the heads or the gaskets. The gaskets were cometics with ARP studs (stock size) torqued to 80lbs. The good thing is that it ran 8.99 at 154 mph at 4110lbs like this.
To address the issue, I'm currently making a number of changes to the cooling system to help ward off this issue. I'm doing a full fill on the block and dry decking the heads. Also making the move to 1/2" studs. I'm gonna reverse cool the heads only via -6 lines pointing directly at the back of the combustion chambers and pulling water out of the heads via -8 lines where the steam ports used to be. Here are some pics of the heads so far.
I don't post my progress on this site much as I have a build thread going on the truck site. If your trying to push a 4-bolt set up with a blower......or like the truck, you can follow along at
http://www.performancetrucks.net/for...h-more-463288/
Just trying to offer what information I have gathered so far. I'm a pretty die hard procharger guy and always enjoy seeing others succeed with centri blowers. Sorry for the long post. lol
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My old 365 with ls9 gaskets and my 402 with felpros have both seen 30 lbs boost from my garrett 88mm. stock size arp studs with a tfs head. I have yet to have any headlifting. I pulled a wrist pin out of the wesico piston and bent the stock crank on the 365. But I'm also 3200lbs. I plan on traping 175
I don't know how accurate those calculators are but the guys going 160-161 in X275 at 3300 with an 88 is showing they need to make 2250hp.... I just don't see am 88 being able to flow that much. if you put the ET they are running the HP level drops by about 300HP. if I put my weight and ET of 4.59 is shows 1300 rwhp. I'm not trying to have a "record" or any BS like that, I just have a goal and I'll get there even if I need to swap heads which will likely be the original TFS ls3 heads I originally had since I bought a Mast intake lol.
I can't remember if he went 70's. But lets say he went 4.75. According to the Wallace calculator it took about 1450 horsepower to run 75 at 2960 (his weight).
Using the same calculator at your 2800lbs and to run 4.50, it would take 1620 horsepower. So you'd have to make nearly 200 more than him in calculator land. Don't let his comments fool you, those guys know exactly what they are doing.
The only person that I know of that has surpassed the 1600 horsepower mark on 4-bolt heads is Kurt Urban, and when asked he will tell you he never did get the heads sealed up. Dry deck or methanol won't matter imo, it'll still be pushing the gasket out and at that level be torching the **** out of the block and head each time.
I hope you do it, but it's a crazy goal with a factory head especially. It's always nice to get a new internet hero every now and then.
Using the same calculator at your 2800lbs and to run 4.50, it would take 1620 horsepower. So you'd have to make nearly 200 more than him in calculator land. Don't let his comments fool you, those guys know exactly what they are doing.
The only person that I know of that has surpassed the 1600 horsepower mark on 4-bolt heads is Kurt Urban, and when asked he will tell you he never did get the heads sealed up. Dry deck or methanol won't matter imo, it'll still be pushing the gasket out and at that level be torching the **** out of the block and head each time.
I hope you do it, but it's a crazy goal with a factory head especially. It's always nice to get a new internet hero every now and then.
It's gonna be a while, been spending alot of money on this thing. I want to hit the track beginning of the year, I'll give you a holler travis maybe we can meet up haven't seen you in a while.
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I've managed to run a 5.08@143 at 3500# with some old ET 4 bolt heads.
I've always lived by the belief that timing is the devil! I keep mine in check.
AFR also plays a huge part I believe People want to flood these things with lots of gas and I think that lifts them too.
Fine tuning what you have. Its alot easier to add more CO2 on the gate vs studying your logs and making adjustments.
Those are some of the things I've done. I'm taking mine back out mid Jan if weather is good and see about getting that 4 sec time slip!
I've always lived by the belief that timing is the devil! I keep mine in check.
AFR also plays a huge part I believe People want to flood these things with lots of gas and I think that lifts them too.
Fine tuning what you have. Its alot easier to add more CO2 on the gate vs studying your logs and making adjustments.
Those are some of the things I've done. I'm taking mine back out mid Jan if weather is good and see about getting that 4 sec time slip!
I've managed to run a 5.08@143 at 3500# with some old ET 4 bolt heads.
I've always lived by the belief that timing is the devil! I keep mine in check.
AFR also plays a huge part I believe People want to flood these things with lots of gas and I think that lifts them too.
Fine tuning what you have. Its alot easier to add more CO2 on the gate vs studying your logs and making adjustments.
Those are some of the things I've done. I'm taking mine back out mid Jan if weather is good and see about getting that 4 sec time slip!
I've always lived by the belief that timing is the devil! I keep mine in check.
AFR also plays a huge part I believe People want to flood these things with lots of gas and I think that lifts them too.
Fine tuning what you have. Its alot easier to add more CO2 on the gate vs studying your logs and making adjustments.
Those are some of the things I've done. I'm taking mine back out mid Jan if weather is good and see about getting that 4 sec time slip!
I don't know how accurate those calculators are but the guys going 160-161 in X275 at 3300 with an 88 is showing they need to make 2250hp.... I just don't see am 88 being able to flow that much. if you put the ET they are running the HP level drops by about 300HP. if I put my weight and ET of 4.59 is shows 1300 rwhp. I'm not trying to have a "record" or any BS like that, I just have a goal and I'll get there even if I need to swap heads which will likely be the original TFS ls3 heads I originally had since I bought a Mast intake lol.
I don't think those are as accurate on a turbo app as the power under the curve is higher than a blower car. stock48 ran 8.22 at 164 mph @3400 lbs with a stock lower end 6.0 cast pistons,rods and bolts,hell his whole engine is stock minus a mild port on the heads. and I do not think that much power as posted above is possible on stock parts. I do however believe he makes 1100 to 1200 and torque near the same and an extreamly efficient car/drivetrain. and the fact that a turbo car makes more power down low and pulls harder on shift recovery.
I don't think those are as accurate on a turbo app as the power under the curve is higher than a blower car. stock48 ran 8.22 at 164 mph @3400 lbs with a stock lower end 6.0 cast pistons,rods and bolts,hell his whole engine is stock minus a mild port on the heads. and I do not think that much power as posted above is possible on stock parts. I do however believe he makes 1100 to 1200 and torque near the same and an extreamly efficient car/drivetrain. and the fact that a turbo car makes more power down low and pulls harder on shift recovery.