Does anyone have a similar engine build to mine and can you recommend, or tell me what camshaft would get me to my 425-440RWHP and TQ goals? You can see my whole build in the conversion/swap section here on LS1tech.com

2004 LQ4 .020 over Speed Pro Hypereutetic pistons, crank turned .010/.010, 317 heads with 04 ZO6 springs and cam,Dougs 1 3/4" headers, 2 1/2 dual exhaust with X pipe and 40 series Flowmaster mufflers,200R4 transmission with 2500RPM stall,GM 12 bolt 3.73 posi.

Original tune was lean(see graph),with Ls1 intake and stock TB. Since dyno/tune, Ive swapped to an LS6 intake,Janzer(Sp?)ported/polished TB. I bought 42gph injectors but have not istalled them because they would require a retune. Because I hate paying or doing things over and over I want to do a LS3 intake,injectors,heads,cam swap and tune all at once.

Winter swap plans include LS3 cylinder heads,LS3/L78 Intake with stock LS3 fuel rail and 39-42gph(stock LS3)injectors,92 or 102mm throttle body and which cam?

Texas Speed 224R or 228R,

Futural 224/232 621/612 -114 +4, or

have Patrick G spec a cam?

 

I'm running an LQ4 with stock L92 heads, and a stock LS3 intake/rails/injectors, and Nick Williams 92mm TB. And with fuel issues (pressure dropped from 60psi to 30 psi at around 5500-5600rpms, because of a wiring issue) I was still able to make 418rwhp/400rwtq right before it cut fuel with my TSP 231/236 cam, on a base tune, with no tweaking. They wouldn't mess with the tune any because of the fuel issues. The cam still has about another 1000rpms or more before it reaches its peak numbers, and it's still technically not tuned. So, I figure that'd easily meet the goals that you're looking for. With fuel issues resolved, and tuned, I'm thinking I should see ~470rwhp, or so. So, I'd recommend the TSP 231/236 to anyone. But, nothing could probably beat having Pat G spec you a custom cam for your goals. As for your other cam choices, a TSP 224R or 228R would probably be a poor choice, as they're spec'd for cathedral port heads instead of the L92/LS3 rectangle ports.

 

Thanks for your input. Are your L92's unmilled? unported?Are your LQ4 pistons dished/stock? If so WOW low compression and still great#s.That was one of my questions,that if you don't mill will the increase in cam lift and duration off set the loss in compression? Most likely not,but I do not want to flycut my pistons,I would rather mill the heads to increase compression and/or run a different cam.

Any one else?

 

Yep, unmilled, unported, and stock/dished LQ4's. I figured it'd still be a pretty good powerhouse N/A, and later on, the lower compression would be good for boost, if I keep it.

 

With 6.0L I would at least get a 232 range cam and easily meet your 440rwhp goal, it will still be a baby cam with that displacement. A 224 or 228 cam is considered small for a ls1. I would get a cam spec'd from PatG or Geoff @ eps that really know their stuff though like you said.

I think Lq4's with l92s and ls3 manifolds have been above 440rwhp with tiny 224 cams.

 

I would also concur with the above opinions. With your displacement and those heads, I would stick to something in the low 230's intake duration to mid/high 230's exhaust. Patrick G knows best with these setups.

 

The question here is were do you want to make you power?

Yes the 230+ duration cams make power, but typically they do not reach 400lbs of tq until 4500+ rpms...... The key to building a street application is building a combination that makes power in usuable ranges ie idle-4500..... Too many max effort cams are thrown around here and promoted or cams that are great for racing dyno's..... I have personally driven some of these max effort cams and they drive like crap from idle-4500 but it looked good and made power on the dyno.... Dyno's are to be used for tuning purposes only, but the unfortunate thing is guys build their combinations and setups to perform well on a dyno vs actual real world street..... If max effort is your concern..... then the car should be setup for the strip, now your talking about shedding weight, better suspension, etc........ If a street appilcation is the goal... I want the best avg power vs best max power.... Because true professionals know that the car that makes the best avg power will be the winner on the street..... and sometimes the strip...

Example:

take 2 cars of equal weight, equal setup etc...... and the same combination, same cam lobe family, same split, different intake duration.....

1.car makes 400LBs of TQ from 2500-6200
2.car makes 400lbs of TQ from 4500-6200

Now which one would be the faster car on the street? I would take 1. all day for a street car.... We spend 98% of our driving time in the idle-4500rpm range.... we spend less than 2% of the time at 5500-6500... So why set up a street car for less than 2% of the time?

"Horsepower sells cars, Torque wins races"-Caroll Shelby.... Horsepower is sexy, but torque is wins races... and running a higher intake duration, holding everything constant is only shifting your torque curve out or extending the point where maxium cylinder pressure reached......

By shifting out your torque curve with extended intake durations, now if its an automatic, to get to that outward shifted torque band, then a higher stall is required..... Example-Now where talking about a 3600-4000stall... A lot of guys really don't have an understanding of what their doing especially following some of the myths going around...... Higher stall and more throttle required to reach that particular powerband, kills mpg...... More rpm required to make power = more stress on the valvetrain and engine itself... High rpm motors do not last long... 20-30k tops(I am talking about motors spun to high rpms consistantly)....

I think the

Futural 224/232 621/612 (out of these choices)- but if the higher rpm is desired 114+2 instead of the +4 to not shorten your power stroke too much....

I would run it on a 112+3 or a 113+4 and call it a day.....

With the Lq4 qnd milling your heads, you will be limited on the max comp you can run anyways and when you start milling down into .030-.040 range, not the issue of quench and geometry of flow issues arise truth be told.....

For a street car stay within the 222-227 range.... Intake duration
6-8* split on the cam, .590-.625 on the lift and a LSA 112-114 and keep the overalp in check around 0-4 and you should be fine.......... 450 easy.... The 227/235 LSL lobes have seem to work in this combination and trap well 120's MPH......

PS do not port and hogg out the heads either....... just mill them for a compression bump....
Also ditch the slowmasters, you don't need any backpressure, especially with L92 heads.....

 

bozzhawg thanks for all the info and your opinion. I could not agree more with your thoughts on all out high RPM/Dyno queens vs under the curve power where you drive it cars. I will consider the Futural cam as well as a Patrick G spec cam.Thanks again.

 

Any one else have a recommendation? Similiar build w/ dyno #s?