stock bottom LE2 cc306 and 5psi?? hp est
02-06-2011, 09:17 PM
#21
Comp's tech line can not be trusted to spec a cam, I don't think you will find anyone knowledgeable who will say otherwise. They do have folks in the company, but they are not talking to every kid who dials an 800 number.
I also think you are being optimistic on your expected results, NA and boosted. With a better heads and a custom cam the highest 6psi blower stock shortblock setup I know of is a little over 480rwhp. IMO you would be real lucky to hit 450rwhp.
I also think you are being optimistic on your expected results, NA and boosted. With a better heads and a custom cam the highest 6psi blower stock shortblock setup I know of is a little over 480rwhp. IMO you would be real lucky to hit 450rwhp.
02-06-2011, 09:24 PM
#22
TECH Resident
iTrader: (13)
Join Date: Nov 2005
Location: west phx
Posts: 782
Likes: 0
Received 0 Likes
on
0 Posts
and fyi for a rear mount turbo setup wrapped stock exhaust manifolds are far superior to long tubes. with a a turbo setup you want to keep the heat in the exhaust, and the stock manifolds do a way better job of that
02-06-2011, 10:57 PM
#24
TECH Fanatic
Thread Starter
iTrader: (8)
Join Date: Jan 2011
Location: Pinellas Park Florida
Posts: 1,550
Likes: 0
Received 0 Likes
on
0 Posts
This is the best responce yet. Tech line or not i already have this cam so im going to try it out and see what it does, When the bottom end id built in the future a new cam will be used. I just wanted to hear some good opinions and numbers on what the set up might make. I wont be to surprised if it makes in the 488rwhp range on 6 psi if nt a little more.
02-06-2011, 11:00 PM
#25
TECH Fanatic
Thread Starter
iTrader: (8)
Join Date: Jan 2011
Location: Pinellas Park Florida
Posts: 1,550
Likes: 0
Received 0 Likes
on
0 Posts
As for the 4 bolt diss, if the car was making over 550rwhp i might consider it a must, but i dont plan on spinning the motor past 6500 or pushing the motor on boost to hard. So i think 600 plus a rebuild for 4 bolt is silly yes
02-07-2011, 12:50 AM
#29
TECH Fanatic
iTrader: (2)
Join Date: Dec 2010
Location: Oklahoma
Posts: 1,084
Likes: 0
Received 0 Likes
on
0 Posts
The hydraulic intensity is greater on the 503 than the 306 which is why it would make a better boosted cam than the 306. The 306's and 503's durations at .050" lift are opposite each other, with the 503's lift being a little bit smaller. The longer duration of the exhaust lobe without added lift gives it much more advantage in boosted applications. With the longer duration in the area it matters, the exhaust gases can escape, but the valve actually closes earlier keeping the intake air from blowing by. Also with the boost the cam doesn't NEED more lift. Duration is actually preferred.
You also don't NEED the intake events to happen earlier you need the exhaust stroke to flow well but also need the valve to close soon enough so that boost doesn't flow right out of the intake to the exhaust.
02-07-2011, 01:50 AM
#30
The 503 is the better OPTION than the 306.
The hydraulic intensity is greater on the 503 than the 306 which is why it would make a better boosted cam than the 306. The 306's and 503's durations at .050" lift are opposite each other, with the 503's lift being a little bit smaller. The longer duration of the exhaust lobe without added lift gives it much more advantage in boosted applications. With the longer duration in the area it matters, the exhaust gases can escape, but the valve actually closes earlier keeping the intake air from blowing by. Also with the boost the cam doesn't NEED more lift. Duration is actually preferred.
You also don't NEED the intake events to happen earlier you need the exhaust stroke to flow well but also need the valve to close soon enough so that boost doesn't flow right out of the intake to the exhaust.
The hydraulic intensity is greater on the 503 than the 306 which is why it would make a better boosted cam than the 306. The 306's and 503's durations at .050" lift are opposite each other, with the 503's lift being a little bit smaller. The longer duration of the exhaust lobe without added lift gives it much more advantage in boosted applications. With the longer duration in the area it matters, the exhaust gases can escape, but the valve actually closes earlier keeping the intake air from blowing by. Also with the boost the cam doesn't NEED more lift. Duration is actually preferred.
You also don't NEED the intake events to happen earlier you need the exhaust stroke to flow well but also need the valve to close soon enough so that boost doesn't flow right out of the intake to the exhaust.
02-07-2011, 07:31 AM
#33
TECH Fanatic
Thread Starter
iTrader: (8)
Join Date: Jan 2011
Location: Pinellas Park Florida
Posts: 1,550
Likes: 0
Received 0 Likes
on
0 Posts
lol I asked numbers not what CAMSHAFT i should use. And what machine work Jay the motor is a STOCK short block with 70k miles on it, if i had machine work done then new rods and lower compression piston would go in. As for a fail box, or breaking something, well anything is possible but i dotn see anything breaking with only 5 psi, and what would be cnsidered a fail box? a motor that does not make any power at all? cause im sure its going to run and make some kinda power. As for the cam , are there better cams....yes...... is this the best possible cam chioice..... Maybe not...... maybe so.... I wanted to test this cam with a few othere to see what kinda power they make and where they make the power in the rpm band.....
So thanks for the cam diss but thats not what i asked about. lets take the turbo out of the ? all together since its confusing some.
What should the cc306 make with an LE2 top end and LT headers?rwhp
So thanks for the cam diss but thats not what i asked about. lets take the turbo out of the ? all together since its confusing some.
What should the cc306 make with an LE2 top end and LT headers?rwhp
02-07-2011, 09:17 AM
#36
TECH Fanatic
iTrader: (11)
Join Date: Sep 2005
Location: fort walton beach,fl
Posts: 1,954
Likes: 0
Received 0 Likes
on
0 Posts
Coming from experience in turboing a stock bottom end'd motor and speaking on behalf of a (lt1), YOU NEED rod bolts the stock ones are not designed to hold the power levels you will see for long. YOU NEED wrapped exhaust to keep the heat to spool the turbo especially on a but mount..I noticed an immediate boost response improvement from trying my front mount unwrapped vs wrapped the boost came on sooner and stronger after wrapping. From experience on a 112 lsa cam YOU NEED a BIG Waste Gate...on a 38mm waste gate i could not control boost any lower than 8-9 psi ..as it just wasn't big enough to bleed off the needed exhaust to stop spooling and spiking , 36 psi inj's would work for 5psi... but, as soon as you hit 8+ boost spikes you will lean and melt a piston...42 psi injectors minimum.
the cam and head choice will already have you at 400rwhp at the crank more like 450-460+? adding a turbo on 8psi boost spike? more like 590+- at the crank....so Broken rod bolts,broken transmission, and new thread. 5psi will be less destructive ..but,save for a trans because it will let go until you build the **** out of it ...i went thru 3 stock ones until i got a built running on 8psi ,
So...from experience on a stock bottom (ls1) with an exhaust bleeding 112lsa cam ,put rod bolts in it, use 42psi inj's,wrap it up,save for a trans,use a big *** trans cooler,dont let it lean...
the cam and head choice will already have you at 400rwhp at the crank more like 450-460+? adding a turbo on 8psi boost spike? more like 590+- at the crank....so Broken rod bolts,broken transmission, and new thread. 5psi will be less destructive ..but,save for a trans because it will let go until you build the **** out of it ...i went thru 3 stock ones until i got a built running on 8psi ,
So...from experience on a stock bottom (ls1) with an exhaust bleeding 112lsa cam ,put rod bolts in it, use 42psi inj's,wrap it up,save for a trans,use a big *** trans cooler,dont let it lean...
Last edited by defaultexistence; 02-07-2011 at 03:20 PM.
02-07-2011, 09:43 AM
#38
WoW, I mean..... Do you... like Owch my *****? lol I guess what I and everyone else are sayinf is we have seen these posts before that ended up with follow up posts of "Yup got it running" and then Going to the track" or "Gona street race a cobra" to more threads that read "New Turbo Engine build" and "Where can I buy a good boost LT1 crate engine". It takes a while for them to admit it but they eventually get to the part where a rod bolt fails and pops a hole in the side of the block or a piston shaters, or what ever. Point is why take the risk on a 70K mile bottom end? Maybe on a vette bottom end maybe but I would still have the rod bolts changed. Like you said at that point just change the pistons and hell why not go through it. Problem is they only made so many LTx engines and I hate to see one go to the waist side on purpose.
02-07-2011, 10:59 AM
#40
TECH Fanatic
iTrader: (2)
Join Date: Dec 2010
Location: Oklahoma
Posts: 1,084
Likes: 0
Received 0 Likes
on
0 Posts
Sorry didn't mean to **** in your cereal or anything. The 306 WILL make power.... but the rpm range for that cam and your stock short block don't match for the turbo setup, but since you asked I could see if you installed it with the 5 psi spring you making anywhere from 460-470 rwhp. remember that the stock rods will only hold ~500 rwhp at least that is a good # to go off of.