300bhp/ton

Background:

Ok I've been faffing about for far too long on which setup I'd like to run, in short it's meant I so far have purchased very little.

But I think I've crakced it, I just need some help designing the cam.


Setup:

The setup will consist of a built 346ci LS1 running LQ9 heads (Stage 2 or 3 from TSP most likely) with ~9.5:1 SCR and a D1SC Procharger. With the usual bolt ons and supporting mods(LT's, LS6 intake, head bolts, oil pump, fuel system, etc.).

I will be aiming for ~14psi of boost


The cam?:

If we assume a cam like this 239/242 .649/.610 on a 111LSA (TSP MS4) is a pretty bad **** of a n/a cam.

What I am after is an equivalent cam in terms of extremeness but more suited to a supercharger application. However I would still like to retain as much lope as possible.

I would be after PEAK Hp at somewhere around 6200-6400rpm with the ability to shift at 6500-6700rpm.

PREDATOR-Z

In supercharger applications, you do not want too much overlap. It is counter productive since you'll be bleeding boost.
Also i would go for a clean 9.0:1 SCR to use 1 BAR without Meth.

But if you insist:
230/236, .592/.602, 115lsa (this would be the highest I would go)
232/238, .595/.605, 115lsa
236/242, .595/.610, 115lsa
238/244, .605/.612, 115lsa

300bhp/ton

Cool, so what would be the affect (HP and performance wise) by going for something like 236/242, .595/.610, 115lsa compared to 230/236, .592/.602, 115lsa?

PREDATOR-Z

When you FI you rely more on boost and not cam size.
If you want my advice, go with a 224/230 .581/.590 114+1. That cam is plenty for a street setup. Now if you want a loud note, then do it via exhaust.

300bhp/ton

True but I'm a little limited on what fuel I can run so my thinking was along the lines of if I can't quite support the boost I wanted then maybe a more wild cam could offer up a tad more performance.

How about an extreme street setup?

Yeah already got a LM, but I love the sound a cammed motor makes, that spluttering loping sound.

JakeFusion

iTrader: (7)

I hate to say this, but when I ran a turbo Supra and a supercharged Stang, the more cam you have the better off you are in terms of power. Boost can be whatever you want to run it at, but the goal is to make more power per pound of boost. So, if you pulley it for 14lbs and only get 9lbs due to headers/camshaft but still make more power than someone else at 14lbs, then you've done what you wanted, no?

Also, remember inlet and exhaust restrictions can up boost - I'd go for the highest flowing intake and exhaust possible, because boost numbers are all well and good, but if you pulley for 14 and get 9, then you can pulley again for an actual 14psi and really make some power. That way you make more power with less boost or much higher power once the boost is really cranked up.

I'd go with a G5X3 from LG on a 114 or the MS3 and some really agressive springs.

LSX-Racer

Agree with this.
Not this though.
The Arizona Power guys have a nice blower grind.

Sean Collins

with your heads i personally would think a camshaft like this might serve you better.

232 int 244 exhuast 114icl 585 lift int 590 exhuast 114 LSA. it'll look wierd in the calculator but it will make power. its gonna be a bear to idle though.

1997bird

iTrader: (2)

The custom cam that I had groud for my cousin's 'vette' is rated at 302 int/exh 234@.050 (that is on a BBC dia cam on the LS1 core it is more like 240 or 242) with .578" lift int/exh with a 112 LSA & 108 int centerline. It idles without any problem's and has great streetability on his 346 stock bottom end. But was origonally designed for the new LS2 short block we will be building this summer. It is going to be a twin turbo set up at 16 lbs. of boost.

mvonada

Camp Cams has a great piece of software for $24.95. You plug in the values of the engine and cam, it will tell you the horsepower & torque output of each cam configuration you plug in. Takes the "what do you think" and guess work out of it.
www.compcams.com

Good luck

allngn_c5

iTrader: (3)

LG Motorsports also offers custom Blower Cams. Just call for details.

2000TransAmWS6

iTrader: (12)

not trying to steal this thread, but i was just wondering...

it seems to me that with a FI motor you would want less valve overlap, so that you could put more air into the cylinders.
is this the right line of thinking?

PREDATOR-Z

If you pulley 14 but only make 9 you are overcammed. Too much overlap will bleed alot and there is where your boost is going, out the exhaust.
as usual it is a matter of combo.
Why does everyone always have this bigger is better gang ho attitude.
balance, poeple balance ie : equilibrium.

JakeFusion

iTrader: (7)

I just noticed I said inlet and exhaust restrictions up boost... that's wrong. Inlet restrictions kill boost and exhaust restrictions up boost. High flowing intakes will actually increase boost while high flowing headers will decrease boost. Together they equal out but give way more power.

For cams, yes too much overlap may allow boost seep, but I really don't think 8-12 degrees of overlap is going to be that much. A T-Rex would probably be too much with 25 degrees of overlap, though.

I ran Comp XE-R 238/240 116 on my 4.6 mod motor and I picked up 70rwhp with the cams and lost 1lbs of boost (with a twin-screw and headers). Granted, the 4.6 mod is a bit different than the LS1 in how it responds to cams, but that cam had 8 degrees of overlap.

Also, I'm not really sure how much overlap it would take to loose 4lbs of boost or more. I should have been more clear with that. The point is, you can bleed off boost and make more power. I'd rather make more power with less boost if possible.

STRIPSTAR

iTrader: (4)

Listen to Predator. You dont need a cam that barely fits on a FI car. You want more exhaust duration and a 114-115 LSA. It will still sound bad *** - 226-230 range is prob about right.
The heavy overlap cams that bleed boost off is usualy only desirable in a motor with too much compresion ratio in the motor.

JPH

iTrader: (2)

222/228 .576/.588 On A 115.

Patrick G

iTrader: (14)

A couple of things to consider:

You may be leaving a lot of torque and hp on the table with a static compression ratio of 9.0:1. 10.0:1 with that blower will make you more power at 14psi. If you plan on running 20-30 lbs of boost, then yes, a lower SCR of 9:1 will work better. But for the average Procharger person (7-14 psi), 9.0:1 is a little too conservative.

Next, overlap can help you with a blower much in the same way it can NA. Although you can run an LS6 cam with very little overlap, shooting for around 10 degrees of overlap (at .050") is pretty smart. If you make 650 rwhp, you need an exhaust lobe close to what you'd run on a 650 rwhp NA motor. You also want an intake valve closing point appropriate for a 650 rwhp motor, but you only need the duration of a 375 rwhp motor if running 14psi (since you're packing twice the air in the same amount of time). Make sense? Pretty complicated on the surface, but it all makes beautiful music in the end. PM me if you want a custom cam profile.

Sean Collins

I just read your post and the only thing you have siad thus far that makes any sense is about the exhuast lobe.

IVO IVC isn't supercritical FI period. thats what the blower is for.Unless of course your an all out pro50 car. Pick a conservative lobe to make good power. Use the boost to make what you can't. Watch Going to big on the exhuast you will hit a point were you bleed of more volume then you gain in cylinder clearing. This will depend on RPM. the cam specs i eluded to should flatline for TQ at 5800 and 6400 for power using a stock LS6 intake. the blower of course will in thoery VIA boost building push the TQ curve out a bit further but not to much. a 246ish exhuast lobe should work well for that air volume.

A word about exhuast here get 1 7/8 headers and a good 4inch single or dual 3inch system. Avoid Flowmaster or other Sound canceling wave design Mufflers. Spin tech Magnaflow etc build the correct types of mufflers for the application. You will find you Engine will become very exhuast sensitive. I once saw a 598 14-71 SC big block pick up 100hp and 120lb ft just by uncapping the headers and it already had dual 4inch.

The rules of FI club

First rule of FI club. Stop worrying about HP per LB of Boost unless you are dealing with a turbocharger.Superchargers are insane power hogs to begin with. The cam for a Turbo application would look very different to work effectively.

Second Rule of FI club. Don't go up on compression unless you can afford the fuel. I think 9.0:1 is a damn smart goal. Workable on pump fuel without to many durability issues.

Third rule of the FI Club don't take advice on supercharger cams from people who don't work with turbos and superchargers alot.

I see so many **** poor running Supercharged and Turbocharged cars i want to pull my hair out.

to adress the compression deal with making power. the idea with a FI application is not to create higher total cylinder pressures but add more volume to in fact extend the pistons Ideal working zone Via Crank Angle Rod Ratio and cylinder Filling. If you can delay the burn and fill the cylinder with the extra Feul/Air will hopefully if everything is timmed right end up having the combustion cycle take place later at a point in the slide crank mechanism where its more beneficial to making TQ with the extra volume.

PREDATOR-Z

Hi Patrick,
Why the change of approach from this thread?
https://ls1tech.com/forums/showthrea...light=camshaft

In England (which is where 300bhp/ton) the octane is similar to California standards and this is why I recomended 9.0:1

When i was FI, unless it was a track setup, lower overlap cams were much more fun to drive.

I think 300bhp/ton should give more input as to the functionality of his desired setup.

PREDATOR-Z

Yeap exactly what I said, basicaly use boost to make the power by filling the cylinder with the biggest charge. That doesn't need to much overlap.
Keep in mind we are talking pump fuel and street setup.