Ragtop 99

iTrader: (7)

I'll bet you would see 20 RWHP from an ORP with dual cutouts compared with your current set-up.

look in external engine for a topic I did a couple weeks ago on the value of a good Y-Pipe. Even on my 346 I could see results from my improving my Y-Pipe.

Quickin

What do you mean by ORP and how can I have dual cut outs unless they are installed right after each collector?

Pro Stock John

iTrader: (34)

Dual cutouts before the cats would pick up power for sure.

Ditching the cats wil make power but the car will be come very loud.

Quickin

I have no room before the cats to put in cut outs. I would have to lose the high flow cats. How much louder would it be with the cut outs closed and no cats?

How about one cut out after the Y came together, would that give me some power?

Nine Ball

iTrader: (38)

There isn't any room on C5s to put the cutouts up front. F-body guys only use cutouts to bypass the muffler. On a C5, you put the cutouts at the back of your midpipes, just before they bend upwards to go over the rear axle. This will bypass your mufflers when they are open. You could possibly pick up 10-15 rwhp or more I'd imagine.

Removing the cats will increase your sound probably 1/2 I'd guess. They also tend to work as mufflers. I've seen some Corvette guys weld in straight thru bullet mufflers in the midpipe to help quiet an offroad system though.

Not sure your rings are bad, you might rig up an oil catch-can to be sure your PCV system isn't sucking the oil dry. My MTI 434ci was pulling in about a quart of oil at 1K miles thru the PCV when I was racing it. The catch-can caught all of it.

Tony

JF WS6

Quicken, offroad pipes are just straight pipes that will replace your cats. Actually, if you wanted the best I'd do a true dual 3" X-pipe setup through some race mufflers like Borla XR1's or something. It will be loud but it would sound good. Also, yes that cam that was recommended is fairly large, but if you want the 500+RWHP numbers that others have gotten you will have to run a bigger cam for that motor like they are also (yes it will probably lope a lil' bit).... but unfortunately as you know, performance is a trade off from comfort sometimes.

IMO, I think a large problem is your blown rings - that might give something back when you get them fixed properly (or could be oil consumption from the PCV like Tony said - check inside your TB for excessive oil buildup.) Also, what heads are on that motor? I'd go with stage III LS6 heads, possibly from someone other than ARE perhaps like GTP or something. Maybe you could have your ARE heads flowed on a independant bench somewhere to see if they flow what they are supposed to? Just something you may want to check out. Hope you get it figured out, and really, don't skimp on the cam and heads cause they will be key to making the power out of that large cube motor.

CHRISPY

Are you the guy that was getting tons of detonation and running Ed Wright tuning?

I bet your oil consumption is PCV related (like 9ball pointed out)

If you weren't the guy with Ed Wright tuning my apologies. If you are and you are hammering it with detonation then you NEED to relfash your PCM to stock and get on a dyno with wideband and LS1 edit.

Cats in your application are 20-25RWHP. I had dual carsound 3 inch cats in my 360 and gained 20RWHP removing them.
Cheers,
Chris

JF WS6

Actually Chris, I'm pretty sure he is the one with the Ed Wright tuning/detonation...... I just assumed he eventually got it wideband tuned on a dyno as everyone was telling him to do so.

CHRISPY

If he didn't and it was detonating like he said he will likely run into serious problems.

Big gamble on a expensive setup like that.

JF WS6

My thoughts exactly........ you don't want to skimp on dyno tuning with a $15K motor. Seems like the big strokers seem to have more issues with the PCV more so than stock cubes. Prolly time for a catch can on there.

Quickin

[quote]
It's dry as a bone.

When I ordered the motor I told ARE I wanted the best heads available, period. Of course not C5R heads though. So I would have expected stage III LS6 heads ported to flow around 330.
I'll know soon enough, the heads are going to Trevor Johnson for a flow check, inspection and a port job.

Thanks, thats my plan this time around, to get it right and to make the power that 436 ci should make.

CHRISPY

Are you still running the ed wright tuning or did you reflash and reprogram?

Quickin

Thats me. But it can't be the tune if using 100 octane cures it, right? I thought that if oil is getting by the rings at WOT I will get detonation and by using higher octane it will make it stop at WOT.

This catch can thing, how do I check to see if this is a possiblity? Just by checking to see if there's oil in the TB and the intake?
If it is the PCV sucking some oil, then I still have a detonation problem at part throttle under load and at WOT.

My power is low for a 436 anyway and fixing the oil problem won't help that, so there must be something up with the motor. Badly ported heads and bad rings are the popular opinion.
Also, I leave a trail of smoke behind when I give it allot pedal every time, or if I rev it in park.

CHRISPY

It most DEFINITELY can be the tune.

You could be running at 15:1 AF or higher and detonating like mad on pump gas.

Then by putting in 100 octane you get rid of audible detonation but are still running at EXTREMELY high temperatures in the combustion chambers, pinging and basically burning the **** out of everything.

You are going to ruin a perfectly good motor.

Also check the PCV setup. With the car idling remove the oil fill cap and place your hand over the opening and note if there is a lot of suction there. If there is excessive suction there you need to make adjustments to your PCV setup.

I can't stress enough HOW BAD IT IS TO BE RUNNING WITH THAT TUNE!!!! Why would you not reflash your PCM And get it properly dyno tuned? It doesnt make any sense. Running the motor like is going to KILL it...

Quickin

Still have Ed tuning. Only because of the oil burn issue and the detonation. I thought why waste my time with a tune if I'm burning 1.5 qrts every 300 miles. Thats the worst case of oil burn I've ever heard of. And the trail of smoke I leave behind points directly to bad rings.

Ed tunes the 2 fastest N/A LS1's in the country, I understand that a tune with the car on a dyno in front of you is the best, but this can't be an Ed problem, it has to be a motor problem. Can a bad tune make me burn that much oil or cause the trails of smoke I leave behind.

Another problem I have which a GM tech told me was coolant, if my car is at operating temp on a hot day and I turn the car off, for about 1 minute after shutdown I have drips of coolant that land on the top of my right-side header collector. It drips at a rate of about 1 drop per second for a minute or so. I've had to fill my radiator about 6 times in the past 3 months. This is just another issue that will be solved with the teardown. Maybe a head gasket.

CHRISPY

Read my post above. Your shitty tune has likely burnt/rattled everything in the motor plus blown headgaskets. EVERYTHING You have stated points to the tune. the PCV fix is simple to do but I think you have wasted a good motor

Quickin

When you say wasted, do you mean it's totally shot?

Because as long as I don't go WOT, the motor runs perfectly smooth and normal like any other motor. The detonation was heard one time, when I first heard it. Then I went WOT for some ATAP logs for a second time. It hasn't seen WOT since then.
If the motor got damaged would it still run perfectly smooth like it does?

Can detonation 2 times cause a head gasket to blow?

Quickin

OOPS, I missed this post, I'll try that right now with the oil cap.
So you think before I do anything I should have an LS1Edit dyno tune?

The A/F is set at 12.8-13.1

Quickin

Chris,

My car is at about 180 degrees (according to the gauge) and there isn't one tiny eency beency spec of suction from the oil fill port. Nothing at all, it's just dead static air.

I've already checked the TB and intake a couple times, there dry.

So, where else can oil be going?

JF WS6

Hmm....... Well, if you're getting no suction and you don't notice any kind of oil build up inside the TB/intake it appears that is probably not be the issue then. If you were detonating badly before I suppose it's possible your rings were damaged at some point causing the oil burning problem and also creating no vacuum in the engine because your rings are gone. You do seem to be burning more oil than what just a PCV problem alone would cause. Your A/F ratio sounds ok for your tune, but you don't know anything for sure until it's properly tuned as Chris was stressing it's possible it isn't what you think it is.

I dunno about your coolant issue but I was reading on the forced induction board and a couple people said ARE installed one of their head gaskets backwards (which could prematurely cause a blown head gasket) but I don't know if they installed the heads on your motor or not. Yeah, sounds like you need to have someone take it apart and have a look like you planned. You'll have to take the heads off anyway just for the head gasket fix. Hopefully when it's apart nothing is torn up/burnt up too bad cause it sounds like some damage has occurred. Atleast this way you can check the heads out and get yourself a little beefier cam in there. With stage III LS6 heads and a 436 with a bigger cam & open exhaust + all the boltons you should be something like 525RWHP or so I'd think. It's a big cube motor and should be laying down much bigger numbers. Although even with your oil burning problem I bet with a GOOD wideband tune you'd be closer to 500RWHP right now, although I probably wouldn't drive the car anymore until you get it taken apart. Good luck! Let us know what you find out.