FuelSlut Posted May 24, 2005 Report Share Posted May 24, 2005 so, i've come across a set of brand new LQ9 heads.... bone stock, brand new, virgin GM heads.... and i'm lookin down an empty glass to get my truck movin just a bit quicker. Does anyone have a good reccommendation as to.... what i should have done/do to the heads (cc/port etc.), what type/size valves i should go with.... must keep in mind that I am radix powered, and I do drive this truck everyday. Also, what camshaft size/duration etc. would go best as a combination.... since the radix falls high end... would/should I look for, a longer curve cam? I'm just trying to get some ideas together, any advise would help greatly.... thanks for the help & support, George Quote Link to comment Share on other sites More sharing options...
wkdivr Posted May 25, 2005 Report Share Posted May 25, 2005 Check out Vinci's page with truck cams. Looks like they have 2 that might work. Also, dig around ls1thech's site for blownchevy's posts on the cam he chose. I really wouldn't bother with headwork. Just my opinion, though. Quote Link to comment Share on other sites More sharing options...
FuelSlut Posted May 25, 2005 Author Report Share Posted May 25, 2005 whatever gets me outta the 13's.... im sitting pretty at 13.3 right now, if i'm doing a cam, i mite as well toss on the heads if i can get em worked for cheap ya know? Quote Link to comment Share on other sites More sharing options...
wkdivr Posted May 25, 2005 Report Share Posted May 25, 2005 A cam change is in the budget for my next mod. It should really complement the Radix! Chevyhiperformance got into the high 12's with their SS without touching heads or cam. Touching up the tune, and doing something to get the intercooler temps a little lower between rounds. Quote Link to comment Share on other sites More sharing options...
FuelSlut Posted May 25, 2005 Author Report Share Posted May 25, 2005 yeah, they also went down to a 2.75 pulley... not completely reccommended for everyday use, i guess i could buy one and use it just on track days and street adventures... but the only diff between my truck and CHPs is pretty much headers... well that and they went with a vig. torque converter, but i think im around the same stall as theirs... when bryan tuned my pcm he used most of what they used on chps.... so i dunno, maybe i should give in and get some headers... but if a cam is cheaper... and i have heads lyin around...??? i dunno Quote Link to comment Share on other sites More sharing options...
wkdivr Posted May 25, 2005 Report Share Posted May 25, 2005 GMHTP did an interesting article about a Radix blown 6.0 for a daily driven truck. It's in the March 05 issue. Pretty interesting stuff. Quote Link to comment Share on other sites More sharing options...
wkdivr Posted May 25, 2005 Report Share Posted May 25, 2005 As far as headers, I wouldn't do anything but long tubes. Stainless Works, or Dynatech Quote Link to comment Share on other sites More sharing options...
BigTex Posted May 25, 2005 Report Share Posted May 25, 2005 I'm more than happy with my ASM headers. I've been running a 2.75 pulley for the past few months. Quote Link to comment Share on other sites More sharing options...
FuelSlut Posted May 25, 2005 Author Report Share Posted May 25, 2005 i would love dynatech headers... but NASCAR loud is not what im looking for... i have corsa catback.... AHHH dont even meantion those headers... i would LOVE to sport em, but i dunno if i could deal with it all the time. Any cam spec reccomendations, anyone? anyone? Buler? Buler? Quote Link to comment Share on other sites More sharing options...
Justin Lamanna Posted May 25, 2005 Report Share Posted May 25, 2005 you'll get better gains from a cam than with headers on our supercharged trucks. probally save some money to. Quote Link to comment Share on other sites More sharing options...
SSLink Posted May 25, 2005 Report Share Posted May 25, 2005 (edited) I am running the LPE GT2-3 cam. Specs at 207/220-.573/.578-118.5 LSA. Good low-end punch off-idle and off-boost. I really don't think I need a bigger stall on the street. This cam was designed for F/I. Wide LSA and no overlap help build boost and give you a stock-smooth idle to boot. High lift to take full advantage of the blower and bigger exhaust duration to scavenge all the boosted airflow. I am sure you can find a bigger power cam but this one is great for daily driveability. I am running a set of factory LS6 heads I picked up cheap. Unusual with a blower because they bump compression to 10.8:1. However, with the Radix I am only seeing 9-10 PSI max boost and the combo works well on 93 or 94 octane. I left the ports untouched because I wanted good velocity on the low end and off-boost for driveability. I am sure though there is power to be gained with a little porting, particularly on the exhaust side. You'll get differing opinions but I don't think hogging the intake side is as important with F/I. I know where you're coming from with the longtubes. Tempting, but I didn't want to go that route either because of the noise level and tinny sound. Right now my truck rocks with good power and excellent street manners and no dirty looks from my neighbors like I used to get with my Camaro SS.This is the combo I was shooting for. Tube length supposedly isn't as important with F/I anyway, although the bigger diameter 2 3/4" primaries will help. Beserker, BenKey, Big Tex and Zippy are all good hands on the board experienced with heads/cam/blower setups. You should check in with them and use the search function for other opinions. As I am sure you know, a lot of tech experience and knowledge has been posted on this board since its inception. It's been a huge help to me. Based some of the research done recently by Zippy and H2Racer, you may be able to get into the 12's with just a smaller pulley, more fuel and a more aggressive tune. I plan on going to bigger injectors soon to try to squeeze a bit more from my setup. Good luck with your decisions and have fun! Edited May 25, 2005 by SSLink (see edit history) Quote Link to comment Share on other sites More sharing options...
zippy Posted May 25, 2005 Report Share Posted May 25, 2005 at your point it's tough on what to recomend. i'll poke around cams here in a few to see what i can come up with for your application. the new heads will be nice since it will allow you to change the valve springs with the heads off and be a direct bolt on. if you do any port work, make it more extensive on the exhaust side than on the intake. the intake side is boosted and at your level is better off left stock or with a mild touch up. the first place i'd recomend starting is with a fuel pump booster from magnuson and some larger injectors. this alone will allow for some much more agressive tuning and allow more room to grow. i'm not sure if you've checked your truck or not yet, but i'd bet it's lean with that smaller pulley on the blower. Quote Link to comment Share on other sites More sharing options...
misterp Posted May 25, 2005 Report Share Posted May 25, 2005 i would love dynatech headers... but NASCAR loud is not what im looking for... i have corsa catback.... AHHH dont even meantion those headers... i would LOVE to sport em, but i dunno if i could deal with it all the time. Any cam spec reccomendations, anyone? anyone? Buler? Buler? <{POST_SNAPBACK}> Dynamat; lots and lots of Dynamat! Quote Link to comment Share on other sites More sharing options...
2nd Sierra Posted May 25, 2005 Report Share Posted May 25, 2005 interesting i didn't know that about long tubes and f/i. The sound of my exhaust pretty much sucks right now in spite of having good quality long tubes and the corsa touring. At WOT it is loud. So shortie or mid length headers will improve sound quality without sacrificing power? sorry about the thread hijack btw I am running the LPE GT2-3 cam. Specs at 207/220-.573/.578-118.5 LSA. Good low-end punch off-idle and off-boost. I really don't think I need a bigger stall on the street. This cam was designed for F/I. Wide LSA and no overlap help build boost and give you a stock-smooth idle to boot. High lift to take full advantage of the blower and bigger exhaust duration to scavenge all the boosted airflow. I am sure you can find a bigger power cam but this one is great for daily driveability. I am running a set of factory LS6 heads I picked up cheap. Unusual with a blower because they bump compression to 10.8:1. However, with the Radix I am only seeing 9-10 PSI max boost and the combo works well on 93 or 94 octane. I left the ports untouched because I wanted good velocity on the low end and off-boost for driveability. I am sure though there is power to be gained with a little porting, particularly on the exhaust side. You'll get differing opinions but I don't think hogging the intake side is as important with F/I. I know where you're coming from with the longtubes. Tempting, but I didn't want to go that route either because of the noise level and tinny sound. Right now my truck rocks with good power and excellent street manners and no dirty looks from my neighbors like I used to get with my Camaro SS.This is the combo I was shooting for. Tube length supposedly isn't as important with F/I anyway, although the bigger diameter 2 3/4" primaries will help. Beserker, BenKey, Big Tex and Zippy are all good hands on the board experienced with heads/cam/blower setups. You should check in with them and use the search function for other opinions. As I am sure you know, a lot of tech experience and knowledge has been posted on this board since its inception. It's been a huge help to me. Based some of the research done recently by Zippy and H2Racer, you may be able to get into the 12's with just a smaller pulley, more fuel and a more aggressive tune. I plan on going to bigger injectors soon to try to squeeze a bit more from my setup. Good luck with your decisions and have fun! <{POST_SNAPBACK}> Quote Link to comment Share on other sites More sharing options...
SSLink Posted May 25, 2005 Report Share Posted May 25, 2005 (edited) interesting i didn't know that about long tubes and f/i. The sound of my exhaust pretty much sucks right now in spite of having good quality long tubes and the corsa touring. At WOT it is loud. So shortie or mid length headers will improve sound quality without sacrificing power? sorry about the thread hijack btw <{POST_SNAPBACK}> "Sound quality" is pretty subjective and pretty much in the realm of personal opinion. However, longtubes definitely make an exhaust system louder and IMHO also have a tinny resonance. If you're looking for an awesome musclecar/NASCAR sound there's nothing wrong with the "quality," but if you want a more refined tone that doesn't bleed everyone's ears as you drive by and sounds a little more OEM I think shorties are a nice compromise. With any header you will pick up a little increase in valvetrain noise but I can tell you it's not bad with my coated JBA's. The theory about longtubes and blowers/turbos is that the exhaust scavenging properties are not as useful with forced induction. Also, most FI guys choose cams with higher LSA's and less overlap and this also makes less use of the strengths of LT's. I am no exhaust guru but I have been told that with FI gains are more from the increase in primary diameter than from an increase in primary length. I am sure there are many who would disagree and I honestly have no hard evidence myself to back up the contention. On my setup the Touring muffler is quite tame except at WOT. Since you already have longtubes I am not sure it would be worth it to go to shorties or back to stock manifolds. You might lose power going down in primary diameter to what is available in shorties. You may want to try just mounting another straight-thru muffler like a Magnaflow in line with your Corsa to get the overall noise level down. Just a thought - are you still running cats? That also makes a big difference in sound level and rasp. Hope this helps. Edited May 25, 2005 by SSLink (see edit history) Quote Link to comment Share on other sites More sharing options...
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