What to expect from addition of Stage 2 heads to blower car?
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From: Bellevue, Wa
Re: What to expect from addition of Stage 2 heads to blower car? from what I have read and experienced myself, you can expect an increase of power under the curve down low, virtually no increase in peak power and I would venture to guess 1-2 psi drop.
check out some of the other posts for info that backs this up. as SJH has told us and it's been proven a few times, it's the blower that's the bottleneck, not the heads.
check out some of the other posts for info that backs this up. as SJH has told us and it's been proven a few times, it's the blower that's the bottleneck, not the heads.
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From: Phoenix, AZ
Re: What to expect from addition of Stage 2 heads to blower car? True. From what I've seen, the blower is going to push pretty much the same amount of air into the engine no matter what heads are on it (up to a point...) that's why you see a slight decrease in psi (that air is no longer backing up in the intake manifold and intake port). I doubt you're going to see much power with Stage II heads. In all honesty, your money might be better spent by buying a new set of LS6 heads and a "blower cam" that will better utilize the effects of forced induction. If you ever decide to change your setup to NA, the LS6 heads will be a nice platform to start from.
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From: Maple Grove MN
Re: What to expect from addition of Stage 2 heads to blower car? What is better about LS6 heads? I am eventually going to get a blower cam. Thats a must. Having more power down low is definately not a bad thing with a cent. supercharger since the blower gives you crap for boost down low. Its not too late to cancel the order for the heads. I just wanted to know what everybody had to say about it first.
Staging Lane
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From: Palm Beach, FL
Re: What to expect from addition of Stage 2 heads to blower car? you will see some gains..
more gains will be seen via cam profiles.
what you need is better exhaust flow..
even tho we have boost to improve the intake side we do not have a pump to remove the spent gases.
That's why velocity porting the exhaust is so important. If you just hog the crap out of them you won't be able to get any flow.
match this with a cam matched for your heads..
ROCKNROLL..
One of the better combo's on heads these days is to get a set of the 6.0 truck aluminum heads, I just got a set, they flow almost as well as LS6, same port designs, and larger chambers with unshrouded valves. You can lower your compression ratio a bit with these and some new gaskets. Light pocket porting makes the exhaust flow much better than the common LS1 head with porting.
Again, get a matching profile cam and springs.
more gains will be seen via cam profiles.
what you need is better exhaust flow..
even tho we have boost to improve the intake side we do not have a pump to remove the spent gases.
That's why velocity porting the exhaust is so important. If you just hog the crap out of them you won't be able to get any flow.
match this with a cam matched for your heads..
ROCKNROLL..
One of the better combo's on heads these days is to get a set of the 6.0 truck aluminum heads, I just got a set, they flow almost as well as LS6, same port designs, and larger chambers with unshrouded valves. You can lower your compression ratio a bit with these and some new gaskets. Light pocket porting makes the exhaust flow much better than the common LS1 head with porting.
Again, get a matching profile cam and springs.
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From: Maple Grove MN
Re: What to expect from addition of Stage 2 heads to blower car? Thanks for the info. I had heard about people using the 6L heads but I didnt know what was good about them. A little drop in compression would be nice.
<img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />
Justin
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Justin
Re: What to expect from addition of Stage 2 heads to blower car? Yeah LS6 heads might flow a little better, but arent they milled LS1 heads? The compression is higher so be carefull, from the factory the LS6 has 11:1 compression. Compared to an LS1s 10.3:1, might be just enough for your 9-11 psi to lift a head or detonate when on LS1 heads you would be pushing it.
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From: Maple Grove MN
What to expect from addition of Stage 2 heads to blower car? Well some of the problem I was having on the dyno was from lead coated O2 sensors. I still have a leak in the passenger side header. One of the bolts refused to go all the way in. So I decided to go ahead and get myself some new heads therefore eliminating the bad thread in my stock head. I think I was just looking for an excuse to get better heads. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> So with those two problems out of the way I'm all good as far as having my LTFTs where they should be. Better than positive 25 at WOT. <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> I ordered a set of Agostino Racing Stage 2 heads. What should I expect out of these heads as far as power if I was to take the easy way out and keep the stock cam? I've never installed heads or a cam before so I dont want to get myself in too deep at one time. I'm currently running 9-10 psi. How much does that usually drop with aftermarket heads?
Any info is appreciated.
Any info is appreciated.
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From: Chi-Town
Re: What to expect from addition of Stage 2 heads to blower car? better heads in a blown application will maybe add a little horsepower and just decrease the pressure in the intake (boost)
get the pressure back up to what it was before with the new heads and your gains should be significant....obviously this is easier with a turbo car
get the pressure back up to what it was before with the new heads and your gains should be significant....obviously this is easier with a turbo car
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From: Maple Grove MN
Re: What to expect from addition of Stage 2 heads to blower car? Yeah, that would be sweet to have a turbo. All ya need to do is turn up that boost control. Us SC guys have to change $80 pulleys. But I see your point about keeping the same boost to see bigger power gains. I'll probably go that route. How much lift can stock heads go to if you wanted to put in a bigger cam?
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From: Maple Grove MN
Re: What to expect from addition of Stage 2 heads to blower car? I'm also thinking maybe I should just get a good blower cam. Then when I take the heads off to replace the head gaskets with some thicker ones I could just get a basic port and polish job done to them to clean up any rough edges. I could get that done pretty cheap or I could just do it myself. That combo would probably yield better results I would think. What do you guys think of this cam? What would I need to make it work with my stock heads?
Good power adder cam. WIth stage 2 heads, headers, intake, pulley, tuning and torque converter, mid 11's NA ,and mid 10's with 125-150 shot are realistic Lift: .563/.563 Dur@.050: 224/228 LSA: 112 114
Would that be good for my setup? If not is there a better one? I found that one on LS1speed.com
<small>[ November 13, 2002, 11:49 AM: Message edited by: 1slowCamaro ]</small>
Good power adder cam. WIth stage 2 heads, headers, intake, pulley, tuning and torque converter, mid 11's NA ,and mid 10's with 125-150 shot are realistic Lift: .563/.563 Dur@.050: 224/228 LSA: 112 114
Would that be good for my setup? If not is there a better one? I found that one on LS1speed.com
<small>[ November 13, 2002, 11:49 AM: Message edited by: 1slowCamaro ]</small>
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From: Chi-Town
Re: What to expect from addition of Stage 2 heads to blower car? picking a cam is going to depend on head flow, overall combination, and header choice
Also you DONT EVER want to use a gasket to change compression ratio. The gasket is there to make your quench height and thats it....i do believe someone told me that LS1 pistons stock are .005 out of the hole
If that is true...you are gonna want a gasket that its somewhere in the .040-.045 compressed range
Also you DONT EVER want to use a gasket to change compression ratio. The gasket is there to make your quench height and thats it....i do believe someone told me that LS1 pistons stock are .005 out of the hole
If that is true...you are gonna want a gasket that its somewhere in the .040-.045 compressed range
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From: LS1.chat
Re: What to expect from addition of Stage 2 heads to blower car? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by JimmyKash:
<strong>Also you DONT EVER want to use a gasket to change compression ratio. The gasket is there to make your quench height and thats it....i do believe someone told me that LS1 pistons stock are .005 out of the hole
If that is true...you are gonna want a gasket that its somewhere in the .040-.045 compressed range</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif"><img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />
<strong>Also you DONT EVER want to use a gasket to change compression ratio. The gasket is there to make your quench height and thats it....i do believe someone told me that LS1 pistons stock are .005 out of the hole
If that is true...you are gonna want a gasket that its somewhere in the .040-.045 compressed range</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif"><img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />
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From: Maple Grove MN
Re: What to expect from addition of Stage 2 heads to blower car? Why do people tell me to use those cometic head gaskets then? They said you can get them in a lot of different thicknesses. I take it this is a bad thing.
Staging Lane
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From: Palm Beach, FL
Re: What to expect from addition of Stage 2 heads to blower car? ok guys one thing to remember is that turbos and blowers don't add a fixed HP.. they add percentages of NA horsepower..
if you start with a 200 HP engine you add 7-8 pounds innercooled you will see 45-50 percent more hp.. don't look at it as this blower adds 142 HP etc.. it makes more power by adding more atmosphere, so if sea level pressure is 14.5 psi.. you add 15# of boost you at 100% more atmosphere.. and thus as long as the inlet air temp is cooled back to ambient you will see about 100% more power ... it's that simple.. so if you make more NA power by adding heads and/or cams you will see more power by adding the same amount of boost as you did before.
one drawback is that people confuse boost vs CFM.. boost is realitive to the back pressure on your system... it's easy to make boost.. blowing into a mcdonalds straw creates boost.. a few pounds in fact.. but it won't make your car any faster.. CFM is what makes the power.. if you upgrade your head/cam and you don't have sufficient enough CFM in your blower you won't see much change...
<small>[ November 13, 2002, 08:02 PM: Message edited by: 10thanvhawk ]</small>
if you start with a 200 HP engine you add 7-8 pounds innercooled you will see 45-50 percent more hp.. don't look at it as this blower adds 142 HP etc.. it makes more power by adding more atmosphere, so if sea level pressure is 14.5 psi.. you add 15# of boost you at 100% more atmosphere.. and thus as long as the inlet air temp is cooled back to ambient you will see about 100% more power ... it's that simple.. so if you make more NA power by adding heads and/or cams you will see more power by adding the same amount of boost as you did before.
one drawback is that people confuse boost vs CFM.. boost is realitive to the back pressure on your system... it's easy to make boost.. blowing into a mcdonalds straw creates boost.. a few pounds in fact.. but it won't make your car any faster.. CFM is what makes the power.. if you upgrade your head/cam and you don't have sufficient enough CFM in your blower you won't see much change...
<small>[ November 13, 2002, 08:02 PM: Message edited by: 10thanvhawk ]</small>
Re: What to expect from addition of Stage 2 heads to blower car? Right, maybe I should go with a smaller pulley. After I had my heads ported and swapped my cam (221/224 561/561 112 lsa) I dropped from 9psi to 6-7 psi. If I run the 11psi pulley it should come back into 9 psi safely right? I am running 42# injectors,225 lph pump in tank, on top of the T Rex and stock pump. So is my fuel system adequate?
Right now Im sitting at 500rwhp 445rwtq. I gained 60rwhp with the Mac mid lengths, the cam, and the mild port job. But to be honest and support what the consensus of this subject says, I dont think the heads added any power.
I plan on getting a LS6 intake as well, and get it all fine tuned with LS1 edit.
Right now Im sitting at 500rwhp 445rwtq. I gained 60rwhp with the Mac mid lengths, the cam, and the mild port job. But to be honest and support what the consensus of this subject says, I dont think the heads added any power.
I plan on getting a LS6 intake as well, and get it all fine tuned with LS1 edit.
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From: Chi-Town
Re: What to expect from addition of Stage 2 heads to blower car? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 10thanvhawk:
if you start with a 200 HP engine you add 7-8 pounds innercooled you will see 45-50 percent more hp.. don't look at it as this blower adds 142 HP etc.. it makes more power by adding more atmosphere, so if sea level pressure is 14.5 psi.. you add 15# of boost you at 100% more atmosphere.. and thus as long as the inlet air temp is cooled back to ambient you will see about 100% more power ... it's that simple.. so if you make more NA power by adding heads and/or cams you will see more power by adding the same amount of boost as you did before.</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">this isnt necessarily true....it all depends on what the blower turbo can push out in terms of airflow in lbs/minute and how good your intake/heads are. I know a person that has a 383 sbf that went 11.70s on motor and with 12psi is going 9.20s @ 150 (traction limited) with a PT88 turbo.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">one drawback is that people confuse boost vs CFM.. boost is realitive to the back pressure on your system... it's easy to make boost.. blowing into a mcdonalds straw creates boost.. a few pounds in fact.. but it won't make your car any faster.. CFM is what makes the power.. if you upgrade your head/cam and you don't have sufficient enough CFM in your blower you won't see much change...</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">this is a good explanation...
<small>[ November 14, 2002, 08:44 AM: Message edited by: JimmyKash ]</small>
if you start with a 200 HP engine you add 7-8 pounds innercooled you will see 45-50 percent more hp.. don't look at it as this blower adds 142 HP etc.. it makes more power by adding more atmosphere, so if sea level pressure is 14.5 psi.. you add 15# of boost you at 100% more atmosphere.. and thus as long as the inlet air temp is cooled back to ambient you will see about 100% more power ... it's that simple.. so if you make more NA power by adding heads and/or cams you will see more power by adding the same amount of boost as you did before.</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">this isnt necessarily true....it all depends on what the blower turbo can push out in terms of airflow in lbs/minute and how good your intake/heads are. I know a person that has a 383 sbf that went 11.70s on motor and with 12psi is going 9.20s @ 150 (traction limited) with a PT88 turbo.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">one drawback is that people confuse boost vs CFM.. boost is realitive to the back pressure on your system... it's easy to make boost.. blowing into a mcdonalds straw creates boost.. a few pounds in fact.. but it won't make your car any faster.. CFM is what makes the power.. if you upgrade your head/cam and you don't have sufficient enough CFM in your blower you won't see much change...</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">this is a good explanation...
<small>[ November 14, 2002, 08:44 AM: Message edited by: JimmyKash ]</small>
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From: Maple Grove MN
Re: What to expect from addition of Stage 2 heads to blower car? So the moral of the story is that if you increase the amount of air your motor can flow by adding new heads/cam or whatever you will not see a significant gain unless you maintain the original boost level. Correct?
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From: Chi-Town
Re: What to expect from addition of Stage 2 heads to blower car? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 1slowCamaro:
<strong>So the moral of the story is that if you increase the amount of air your motor can flow by adding new heads/cam or whatever you will not see a significant gain unless you maintain the original boost level. Correct?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">eh, sorta
look at it this way:
heads/cam on a blower/turbo car with no change in pulley/wastegate pressure = a level 5 improvement (1-10 scale)
heads/cam on a blower/turbo car with a change in pulley/wastegate pressure to achieve the same pressure before heads/cam = a level 8 improvement
make more sense?
<strong>So the moral of the story is that if you increase the amount of air your motor can flow by adding new heads/cam or whatever you will not see a significant gain unless you maintain the original boost level. Correct?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">eh, sorta
look at it this way:
heads/cam on a blower/turbo car with no change in pulley/wastegate pressure = a level 5 improvement (1-10 scale)
heads/cam on a blower/turbo car with a change in pulley/wastegate pressure to achieve the same pressure before heads/cam = a level 8 improvement
make more sense?
