Anyone have Dyno Results for FI 4.6l before and after ported heads?
09-12-2012, 09:18 PM
#1
Anyone have Dyno Results for FI 4.6l before and after ported heads?
Hi All,
My JDM Short Block 5.0 stroker is done. I am planning on running a 15lb pulley on my KB 2.6 with a Stage II Comp Cams grind that uses the stock springs.
My target rwhp goal is a max of 650 rwhp. My tranny is a new Magnum XL with a 2.66 first gear and a RST clutch.
I am trying to find out if the extra $2000 or so is worth it to port the stock heads.
My guess is that the boost would drop a little (which is good for heat) and it would yield about 20 to 30 rwhp, but if anyone has done this, I would love to hear the results.
If just adding the Stage II cams at 15 lbs of boost and Methanol/water injection will get me 625 to 650 rwhp, then I will do that.
My JDM Short Block 5.0 stroker is done. I am planning on running a 15lb pulley on my KB 2.6 with a Stage II Comp Cams grind that uses the stock springs.
My target rwhp goal is a max of 650 rwhp. My tranny is a new Magnum XL with a 2.66 first gear and a RST clutch.
I am trying to find out if the extra $2000 or so is worth it to port the stock heads.
My guess is that the boost would drop a little (which is good for heat) and it would yield about 20 to 30 rwhp, but if anyone has done this, I would love to hear the results.
If just adding the Stage II cams at 15 lbs of boost and Methanol/water injection will get me 625 to 650 rwhp, then I will do that.
09-14-2012, 11:07 AM
#2
2nd Gear Member
Join Date: Nov 2007
Location: CO
Posts: 439
I don't have the comparison for FI but I do for N/A. Probably won't suite your needs. I have done quite a bit of research on H2O/Meth injection though. I like the idea, but I've come to the conclusion that it is best used as a last resort to get the absolute most out of a given power combination.
I think I'd do the heads before H2O/Meth and upgrade the valve springs while the heads are out. Since you already have FI and built motor, I think the heads would be money well spent. P&P'd heads will improve volumetric efficiency of the motor-blower combination. You might lose a little torque on the bottom end, but with a stroker and KB, that really shouldn't be much of an issue. The top end will really open up and your HP curve should climb all the way to red-line. My tuner sent my heads to Total Engine Airflow and with an upgraded spring set, I think I paid $1800.
H2O/Meth might get you to your HP goal for fewer dollars, but it adds a level of complexity that may not be necessary, and not very many tuners are keen on tuning for it. You need to make sure you find not only a good tuner, but someone who is good at tuning for H2O/Meth. If the system should fail for any reason, you could do serious damage to your motor in short order. H2O/Meth is a chemical bandaid for increased heat. It is likely to increase HP and TQ across the board, but the shape of the curves probably won't change much. If your peak HP is at 5800 and redline is 6500, are you really gaining where you want to? For a daily driver that never sees the track, the answer may be yes. At the track the answer is probably not. The guys that manufacture the H2O/Meth kits will tell you how you can improve fuel efficiency for daily driving, but you have to keep in mind they are trying to sell you something. I haven't seen too many actuall user accounts of improved fuel efficiency or drivability with H2O/Meth. The most common observation I've seen among users seems to be that when they do pull the heads after having used H2O/Meth is that they are as clean and shiney as the day they were born.
Ideally, you do both and set up an aggressive H2O/Meth tune for the track that is essentially a race-gas tune, only you have the advantage of being able to using pump gas. Maybe you go so far as upping the boost at the track.
I think I'd do the heads before H2O/Meth and upgrade the valve springs while the heads are out. Since you already have FI and built motor, I think the heads would be money well spent. P&P'd heads will improve volumetric efficiency of the motor-blower combination. You might lose a little torque on the bottom end, but with a stroker and KB, that really shouldn't be much of an issue. The top end will really open up and your HP curve should climb all the way to red-line. My tuner sent my heads to Total Engine Airflow and with an upgraded spring set, I think I paid $1800.
H2O/Meth might get you to your HP goal for fewer dollars, but it adds a level of complexity that may not be necessary, and not very many tuners are keen on tuning for it. You need to make sure you find not only a good tuner, but someone who is good at tuning for H2O/Meth. If the system should fail for any reason, you could do serious damage to your motor in short order. H2O/Meth is a chemical bandaid for increased heat. It is likely to increase HP and TQ across the board, but the shape of the curves probably won't change much. If your peak HP is at 5800 and redline is 6500, are you really gaining where you want to? For a daily driver that never sees the track, the answer may be yes. At the track the answer is probably not. The guys that manufacture the H2O/Meth kits will tell you how you can improve fuel efficiency for daily driving, but you have to keep in mind they are trying to sell you something. I haven't seen too many actuall user accounts of improved fuel efficiency or drivability with H2O/Meth. The most common observation I've seen among users seems to be that when they do pull the heads after having used H2O/Meth is that they are as clean and shiney as the day they were born.
Ideally, you do both and set up an aggressive H2O/Meth tune for the track that is essentially a race-gas tune, only you have the advantage of being able to using pump gas. Maybe you go so far as upping the boost at the track.
09-14-2012, 11:33 AM
#3
4th Gear Member
Join Date: Feb 2008
Location: Georgia
Posts: 1,761
Meth injection is not the way to go with a KB, it's a very temp solution..
OP, at 15PSI on a KB I would highly reccomend getting a larger heat exchanger, larger intercooler expansion tank, and maybe even a larger coolant expansion tank.. That will help a lot in keeping it cool.. KBs run hot, real hot and the last thing you want is your car to start pulling timing because of the IAT2s..
As for heads, I'd be interested in seeing this too.. I've been thinking about doing mine but don't know if it's really worth it. Or just getting lower CR pistons and upping the boost..
On that note though, I don't think you'll have any problem reaching your power goal with a built stroker and 15PSI.. What kind of stroker did you go with?
OP, at 15PSI on a KB I would highly reccomend getting a larger heat exchanger, larger intercooler expansion tank, and maybe even a larger coolant expansion tank.. That will help a lot in keeping it cool.. KBs run hot, real hot and the last thing you want is your car to start pulling timing because of the IAT2s..
As for heads, I'd be interested in seeing this too.. I've been thinking about doing mine but don't know if it's really worth it. Or just getting lower CR pistons and upping the boost..
On that note though, I don't think you'll have any problem reaching your power goal with a built stroker and 15PSI.. What kind of stroker did you go with?
09-14-2012, 02:27 PM
#4
trexgawd - I have a JDM 4.6 Stroker with the best I can put in the short block. I was not using the meth injection for timing advance, I am using the meth with a small nozzle as a fail safe for bad gas. I am running 22 degrees right now and want to keep it there. I already have 2 heat exchangers with 3 spal fans. Aluminum tubing. My actual coolant temp after 1 hour of traffic in 90 degree weather never topped 107 degrees.
breathegood - I was just curious about dyno results with the KB because I am using a 127205 stage II nsr cam (maybe will change out the springs because the boost might pull open the stock springs) and I wanted to justify the cost... I am just using the meth as a fail safe with a small nozzle at 10lbs +, not to advance the timing... I also considered E85, but the difference in the ethanol content in this region pump to pump and season to season is a hassle.
breathegood - I was just curious about dyno results with the KB because I am using a 127205 stage II nsr cam (maybe will change out the springs because the boost might pull open the stock springs) and I wanted to justify the cost... I am just using the meth as a fail safe with a small nozzle at 10lbs +, not to advance the timing... I also considered E85, but the difference in the ethanol content in this region pump to pump and season to season is a hassle.
09-14-2012, 02:53 PM
#5
4th Gear Member
Join Date: Feb 2008
Location: Georgia
Posts: 1,761
Honestly I would give it a run first.. I have mine making around 500 rear at 10PSI... I would imagine with a stroker and 5 pounds more, and you're keeping it cool you'll be good to go.. The 2.6 can breath some air pretty well.. Any idea what your CR is with that stroker kit?
09-14-2012, 03:59 PM
#6
Stock compression 9.8:1. Most builders use that compression for the street from what I see...
I don't have the comparison for FI but I do for N/A. Probably won't suite your needs. I have done quite a bit of research on H2O/Meth injection though. I like the idea, but I've come to the conclusion that it is best used as a last resort to get the absolute most out of a given power combination.
I think I'd do the heads before H2O/Meth and upgrade the valve springs while the heads are out. Since you already have FI and built motor, I think the heads would be money well spent. P&P'd heads will improve volumetric efficiency of the motor-blower combination. You might lose a little torque on the bottom end, but with a stroker and KB, that really shouldn't be much of an issue. The top end will really open up and your HP curve should climb all the way to red-line. My tuner sent my heads to Total Engine Airflow and with an upgraded spring set, I think I paid $1800.
H2O/Meth might get you to your HP goal for fewer dollars, but it adds a level of complexity that may not be necessary, and not very many tuners are keen on tuning for it. You need to make sure you find not only a good tuner, but someone who is good at tuning for H2O/Meth. If the system should fail for any reason, you could do serious damage to your motor in short order. H2O/Meth is a chemical bandaid for increased heat. It is likely to increase HP and TQ across the board, but the shape of the curves probably won't change much. If your peak HP is at 5800 and redline is 6500, are you really gaining where you want to? For a daily driver that never sees the track, the answer may be yes. At the track the answer is probably not. The guys that manufacture the H2O/Meth kits will tell you how you can improve fuel efficiency for daily driving, but you have to keep in mind they are trying to sell you something. I haven't seen too many actuall user accounts of improved fuel efficiency or drivability with H2O/Meth. The most common observation I've seen among users seems to be that when they do pull the heads after having used H2O/Meth is that they are as clean and shiney as the day they were born.
Ideally, you do both and set up an aggressive H2O/Meth tune for the track that is essentially a race-gas tune, only you have the advantage of being able to using pump gas. Maybe you go so far as upping the boost at the track.
I think I'd do the heads before H2O/Meth and upgrade the valve springs while the heads are out. Since you already have FI and built motor, I think the heads would be money well spent. P&P'd heads will improve volumetric efficiency of the motor-blower combination. You might lose a little torque on the bottom end, but with a stroker and KB, that really shouldn't be much of an issue. The top end will really open up and your HP curve should climb all the way to red-line. My tuner sent my heads to Total Engine Airflow and with an upgraded spring set, I think I paid $1800.
H2O/Meth might get you to your HP goal for fewer dollars, but it adds a level of complexity that may not be necessary, and not very many tuners are keen on tuning for it. You need to make sure you find not only a good tuner, but someone who is good at tuning for H2O/Meth. If the system should fail for any reason, you could do serious damage to your motor in short order. H2O/Meth is a chemical bandaid for increased heat. It is likely to increase HP and TQ across the board, but the shape of the curves probably won't change much. If your peak HP is at 5800 and redline is 6500, are you really gaining where you want to? For a daily driver that never sees the track, the answer may be yes. At the track the answer is probably not. The guys that manufacture the H2O/Meth kits will tell you how you can improve fuel efficiency for daily driving, but you have to keep in mind they are trying to sell you something. I haven't seen too many actuall user accounts of improved fuel efficiency or drivability with H2O/Meth. The most common observation I've seen among users seems to be that when they do pull the heads after having used H2O/Meth is that they are as clean and shiney as the day they were born.
Ideally, you do both and set up an aggressive H2O/Meth tune for the track that is essentially a race-gas tune, only you have the advantage of being able to using pump gas. Maybe you go so far as upping the boost at the track.
Meth injection is not the way to go with a KB, it's a very temp solution..
OP, at 15PSI on a KB I would highly reccomend getting a larger heat exchanger, larger intercooler expansion tank, and maybe even a larger coolant expansion tank.. That will help a lot in keeping it cool.. KBs run hot, real hot and the last thing you want is your car to start pulling timing because of the IAT2s..
As for heads, I'd be interested in seeing this too.. I've been thinking about doing mine but don't know if it's really worth it. Or just getting lower CR pistons and upping the boost..
On that note though, I don't think you'll have any problem reaching your power goal with a built stroker and 15PSI.. What kind of stroker did you go with?
OP, at 15PSI on a KB I would highly reccomend getting a larger heat exchanger, larger intercooler expansion tank, and maybe even a larger coolant expansion tank.. That will help a lot in keeping it cool.. KBs run hot, real hot and the last thing you want is your car to start pulling timing because of the IAT2s..
As for heads, I'd be interested in seeing this too.. I've been thinking about doing mine but don't know if it's really worth it. Or just getting lower CR pistons and upping the boost..
On that note though, I don't think you'll have any problem reaching your power goal with a built stroker and 15PSI.. What kind of stroker did you go with?
Honestly I would give it a run first.. I have mine making around 500 rear at 10PSI... I would imagine with a stroker and 5 pounds more, and you're keeping it cool you'll be good to go.. The 2.6 can breath some air pretty well.. Any idea what your CR is with that stroker kit?
09-14-2012, 04:38 PM
#7
4th Gear Member
Join Date: Feb 2008
Location: Georgia
Posts: 1,761
09-19-2012, 09:07 AM
#8
2nd Gear Member
Join Date: Nov 2007
Location: CO
Posts: 439
1) Insurance - build and tune your setup to attain the HP goal without H2O/Meth, add H2O/Meth with minimal re-tuning and drive away. You get peace of mind but very little performance advantage. If it fails, you can still drive it home. $/HP = very high.
2) Maximum performance - You have pushed your setup to it's limit and you want more. Add H2O/Meth, tune for it and trust that it won't fail. You get the maximum performance out of your setup, but if it fails, your car is on the tow truck. $/HP = reasonably low
There really isn't much in between when it comes to H2O/Meth injection.....at least from the research that I have done. For 625-650 whp @15psi, I think you're going to need heads regardless.
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