Noob44

iTrader: (9)

I have been looking at this cam...

https://www.summitracing.com/parts/cca-54-463-11

In the notes it says you need cathedral port heads, but in the description area it says you can use it for LS3 rectangular port heads. Is this a mistake? Thanks for any input guys!

G Atsma

I would say it would work either way, though it should have a bit more duration split for the LS3 heads. Just my .02...

farmington

iTrader: (14)

that is a HUGE camshaft.

Mappinsj

not huge but it is on the large side. Not a donkey dick .700 lift cam

KW Baraka

iTrader: (7)

Yeah.....this IS a big freakin' cam.
What engine are you putting this in?
What's your projected compression ratio?
What's your car's weight (approximately) and projected use?

I would say that for 90% of the people building an LS engine, this is way more cam than you need.

KW

Mappinsj

I looked at lift not duration. Dear lord

KW Baraka

iTrader: (7)

LOL.....I kinda thought you simply missed that

KW

Noob44

iTrader: (9)

Its going in a LQ4 408 with 11.0:1 compression. The vehicle will be a 2004 Cadillac XLR. 80% weekend driver, 20% track. The shop I had my block work done at said thats the cam he recommends. He said they have had some great numbers put down with that one. figured I would start researching it and thats when I found the summit link with the contradicting info. Figured someone might know whats going on with it that smarter than me.

KCS

iTrader: (20)

Comp's website says it's intended for a cathedral port head. Summit probably copy and pasted the same thing for a bunch of cams regardless of application. Depending on what heads you have, it should work ok in a 408ci engine.

64post

iTrader: (5)

It's 23* of overlap, it will not be very tame.

KCS

iTrader: (20)

I don't think it will be THAT bad. Here's an idle vid of a smaller engine with more overlap:


It's a 383ci LS1 with an old TR V2 Stroker cam (247/251 112+2LSA). I would think a 408 would tame it down even more, even with a little more exhaust duration on the Comp Cam in the OP.

Double06

Probably too big for what you are doing. The LS3 rectangle port needs like 15 degrees between intake and exhaust. If you go a few more pages in the Comp Cam book they have the rectangle port section and the 247 intake lobe goes with a 263 exhaust lobe. Not to say you will not get good numbers but it will surge and be a little soggy down below. I have a similar cam in my 454 C6 Z06 but that is 50 more cubes and probably 600 pounds lighter. It works well puts out good power and TQ. I presume this is an automatic so you need a good converter. The question you have to ask yourself is do you want to cut 10-15 degrees off the intake and exhaust and have a better driving car all around for a loss of maybe 10 hp? The car even with a smaller cam will still have a nice idle - DO NOT BUY A CAM BASED ON ITS SOUND. Also the springs you need are the Comp 926 which have a nose load of 450 pounds so you better upgrade your valve train and your factory lifters, pushrods, rocker arms are not going to like the 450 pounds of load.

neblackshirts

Guess it all comes down to personal preference on how you want to car to act. But everyone here is offering some good advice and thought I'd offer my opinion.






Here's a run down of what I'm running and it's a 408cid motor




Heads - AFR Mongoose 230cc / 62cc
Injectors - 60# FAST
Intake - FAST 102MM
Throttle Body - FAST 102MM
Fuel Pump - Aeromotive Stealth 340
Block - LQ9 4.03"
Cam - Comp 243/251, .624/.624, 111+1 LSA
Crank - Lunati 4.00" Stroke
Pistons - JE 12cc Dished for 11:1 compression
Rods - Lunati 6.125" H-Beam


To be honest I'm on the fence with downsizing the camshaft as I rarely race the car and would rather enjoy it more so on the streets and maybe a small road trip now and then. But I have had numerous shops work on the Tune and so the last shop that tuned it "The Shop, Inc." here in Lincoln have been the only ones that could get it close to being livable. But everyone says between the large cam and 102TB it's a constant battle with cold starts and low air flow situations.
I also have 12-Bolt 3.73 a built 4l60e with a 3600 stall Yank converter which would be a must with a cam that size. I'm going to try out a set of Injector Dynamic injectors and a different throttle body to try and help matters but I'll probably end up changing the cam before much longer. Plus I'm thinking about doing a supercharger setup in the future.

JoeNova

The description at the bottom is for the Comp LSR series camshafts, not that particular cam.

Noob44

iTrader: (9)

This is exactly the kind of info I needed. I will definitely talk to him and see about cutting it down a bit. I appreciate all the info guys! Thanks a bunch guys

AINT SKEERED

iTrader: (2)

It will work well on a 408 bit i would go up in compression. 12.to 1 or so

64post

iTrader: (5)

KCS, I tried to buy that cam from Thunder racing but they had closed their doors.