speedtigger

iTrader: (16)

I have completed my build and it is a great success. I just wish I had more lope in the idle. So, I am considering putting in a new, larger cam profile. I have a pretty good idea, what I would design, but I thought it would be fun if everyone said what they thought would be ideal. I have already sent Patrick G $25 bux, so when he is done, we can compare what we all came up with to what he suggests. Fun stuff.

Parameters:
The cam must utilize my existing PAC 1518 beehive springs.
I will be shifting no higher than 6500 RPM.
The cam must have enough vacuum to run my power brakes.
I want to maximize power, but I don't want to beat the hell out of my springs. I drive my car a lot.
I will not be changing my torque converter or rear gear.

Here is the set up.
1965 Skylark - 3500 lbs.
LQ9 with PRC Stage 1 CNC LS6 heads
10.88:1 compression
Performer RPM intake
Holley/Pro-Systems 780 CFM HP series carburetor
MSD 6010 ingition
Current Camshaft - 222/224 .566/.568 112 lobe separation on 110 Intake Center Line
Th200-4R transmission
3000 RPM Circle D converter
3.90 rear gear
28" tall tire

I will go first. I am thinking a Torquer V2 with a 110 lobe separation would be perfect. So: 232/234 .596/.598 on 110.

Here is a picture of the subject.

garygnu

he knows cams better then 99.9% of the people on here,I would go with what he specs out.

speedtigger

iTrader: (16)

Well that isn't very much fun is it? Come on Gary. Start spitting out some numbers. Let's see what you got. I am killing time til' I leave for the track and this is entertainment.

intenseblue

iTrader: (1)

I see it getting a lower duration with a wider split. Could be wrong though

STAR

iTrader: (1)

I will guess something like a 226/236 112+3

speedtigger

iTrader: (16)

The car ran a 7.46 at 92 in the 1/8th tonight with the little cam. That performance is discouraging me from messing with the formula.

zacht

iTrader: (18)

ill shoot a number!

230/236 .580/.590 110+4

kinglt-1

iTrader: (26)

228/234 .60x .60x 111+4

itsslow98

iTrader: (18)

EPS 226/234 112 or EPS 230/238 112

Your 3000 stall is gonna limit driveability with a bigger cam then what you have.

lemons12

iTrader: (71)

226/228 .588 112

However.. I'm not sure I would go through the hassle and money for that swap.

Converter and 6500 rpm will limit you going too large.

speedtigger

iTrader: (16)

That may be true too. I was shifting at 6200 at the track tonight and had high 1.6 60' times. Everything seems to be working well together. A bigger cam would have to hurt the 60' times with this 3000 converter.

lemons12

iTrader: (71)

Have you considered moving to a 3600? That would set you in the 1.5x area and knock a solid .15-.20 off your et.
The difference on the street wouldn't be too noticeable, nothing you couldn't get use to after a weekend cruise.
I know, I know.. You said you won't change! Just curious why I suppose since the difference is so small but the performance is nice.

I just think that along with a bit larger cam.... Possibly 7.1s@95 1.5 short time in the same DA?

If not I understand..

PREDATOR-Z

increase overlap without increasing durations too much. Also look at a trans brake, which will raise your stall take off speed.

HAZ-Matt

iTrader: (8)

What is the current idle speed? Perhaps you should just lower it to make it more lumpy.

speedtigger

iTrader: (16)

It is at 700 to 750 in gear. Anything lower than that and it gets a little fussy.

smg267

iTrader: (23)

I usually charge to spec cams but I'll let this one go today.

/ .666 .666 LSA

Advanced Induction

iTrader: (2)

Depending on the mileage you'd like to get out of your springs & the swap interval you're amenable to, I'd likely not change cams. Much of what is being discussed is toward the opposite end of the range of aggressiveness out there.

Tall tire, not a great deal of gear, not a great deal of converter, etc.... Perhaps another mild grind in the same duration range on a tighter lobe separation if you really want the noise w/o being detrimental to spring life & how it runs.

seadoo

No doubt go with what Pred.Z or AI says.... AI is the king of LT1's and really are showing what they got with the GenIII+ now too. and Pred. Z is great at designing cams that make KILLER torque!

I would think your cam on a 110 would be great! But also talk with EPS, their lobes make great power and are the easiest on the valvetrain out of any other lobes. I bet Geoff could do their famous 222/226 115 on a 112 or lower for more lope. Search threads for EPS 222/226 you will find all kinds of killer numbers.

BTW, here is a thread about EPS's 222/226 on a smooth as silk, stock longblock LS6 in a camaro. really impressive. https://ls1tech.com/forums/dynamomet...results-2.html

01ssreda4

iTrader: (96)

Go bigger duration on your cam like a V2 and your car will be slower at the track. You combo is working well together now, jumping to a low 230s cam will throw that out the window IMO. I wouldn't switch cams at your point just for sound while possibly losing performance.

speedtigger

iTrader: (16)

Interesting thoughts guys. I was shifting at 6200. I did not test different shift points. 6200 just sounded and felt right to me. I would like to see it pull hard to a 6500 shift point. The car was dead hooking when flashing the converter from 1800 RPM. I did not look to see what it was flashing to. The 60's were in the high 1.6s. I was thrilled with that. If the car 60' slightly slower, but made up for it in ET hustling out the back door, I would take that trade off. On the street, that is a better situation as this car will never dead hook on the street.

I have to say though, we would not even be having this conversation if the car had more thump at idle. This camshaft reminds me of an old Chevrolet small block Chevy cam we used to call "The 151 Cam" (because of the GM part number). That cam ran fantastic in street cars, but it had one of those idles that was neither here nor there. It did not lope steady and it would not idle totally smooth, so it always just kind of sounded like that car was poorly tuned. Great cam lousy idle.

I have read from a few guys who take the TSP 228 cam and grind it on 110 lobe separation and have great results. That might achieve what I want without making the bottom too soggy. I am not in any hurry to tear into this engine again any time soon, but I would enjoy the cruising experience more with some thump while sitting at a light.