I picked out these items for my tired LS1 today:

BTR Stage 3 cam
LS6 intake
LS3 head gasket kit
CNC ported 243 heads

My power goal is 400 HP at the wheels and still have good street manners and no codes. Long tubes and high-flow cats don't pass smog in my neck of the woods, so I have to stick with the stock exhaust. Are my expectations realistic?

Thanks,
D

 

BTR stage 3?, with stock exhaust?, and good street manners?!

NO

 

I'd have to agree Navy on this...with my own 2cents. All an engine is an air pump that makes cool noises

Here is what I see

• That cam...is pretty aggressive. I'd stick with something in the 228/228 .600/.600 lift if you want to maintain street drivability (TSP or BTR). If this is a race car for you...then swing big...but big cam's have big cam manners.
• The ported CnC heads, that's what you want in your quest for 400 WHP so if you can afford it, go for it.
• LS6 intake...yesssssssirrrrr

Where your plan ***** the bed is the stock manifolds and exhaust. It's why I started my post with the air pump analogy. Essentially you are providing the engine with ALL THE CAPABILITY IN THE WORLD to inhale more fuel and air...then chocking the absolute **** out of it on the exhale. Its ying and yang...the more air in...you gotta make the changes to get that exhaust out. THIS my friend...is what makes hurssssspurs and torxs

Not saying that your parts list wont work (as you can always upgrade to headers or exhaust later), you just wont be reaping the max benefits until you do. Don't shoot for mythical HP figures...lot of good money has been wasted in pursuit of it. I'd say LS6 intake, cam, lifters, trunion kit for rockers and you see how the car feels. If that aint enough stank for your...drop the 1,800 in heads and headers...and keep on rolling towards your satisfactions meter. It just seems like a waste of money to spend close to two grand for better breathing heads...all to be chocked up by stock manifolds and exhaust.

My 2 cents.

Joe

 

Joe,

Thanks for the take here. So, in a strict smog arena, how do I get around this? I dropped by my local emission guy's shop yesterday and just asked him outright if he would fail with some high flow cats, and he told me they scan it and visually inspect. He said if the cat is moved further south, is smaller than expected, or if the O2 has a spacer on it, it's a fail. He also said I am allowed one not ready, which the high flows would produce, so any other code and I would fail.

How many of these "hurssssspurs" am I leaving on the table with the cast iron manifold? I can live with 20-25.. 40+... I would probably have regrets.

Can the stage 3 be tuned to a happy state under 2000 RPM? It's a convertible that will never see the track. She's my weekend warrior that sometimes has to transport my wife on leisurely drives.. (Another reason to pass on the headers.. ) But I want to bring it up to current power numbers, such as the base C7 produces. I realize they get there with more cubes and more fuel, but I am hoping I can find a sweet spot where I can leave a dust cloud behind me when I want, and still maneuver a parking spot at a McDonalds drive-thru..

400 not possible without headers?

Thanks,
D

 

I to live in a metro area with emissions test every two years. The law here in Virginia is as such...anything 25 years and younger gets a visual and an OBDII test. No codes, not CEL = PASS. The VISUAL is where the inspector has discretion. Does he wanna crawl his fat A$$ up under the car or not . More stringent inspectors look at the emission sticker under the hood and if its missing anything, has the secondary air disconnected [headers], or has ANY modifications to the OE emission design...they have the right...to fail you. The shops I go to, the inspectors all have cool cars to so as LONG as im OBDII compliant...it passes. I recommend you find a similar workshop where they will just plug up your OBDII and hand you a pass and give you a compliment on your long tube headers

As far as the hurrrspurs, its kind of hard to say but I'd suspect 20 or less. Cant really think of these items in singular terms as they all work in concert to move fuel and air [and in the case of headers and tube...exhaust]. Plenty of guys rocking stock manifolds with axle back exhausts making good power and have no heartburn when waiting in the inspection line.

The Stage 3 cam...i'm new to the LS world but in basic terms...its a SBC 350 is how i like to think about it. Having owned several muscle cars with SBC 350/400 with big cams, I know that they can be a pain in the *** to tune and make behave how you want [which by your own admission is to take your lady for a nice ride and goose the skinny pedal from time to time]. Big cams = stalling at lights, sketch brakes due to low vacuum to the break booster, smelling like fuel because the carb has to be tuned as such to keep it happy idling at 950 rpms lol This is my experience with carb'ed V8 chevy applications that I can personally attest to. Maybe someone else chimes in to provide actual feedback on the cam as it pertains to an LS1, but in my general experience, and over cam'ed 5.7 always leave the owner disappointed.

A MUCHHHHHHHHHH cheaper and instant gratification mod to achieve your goals would be a gear change. Are you rocking 2.73? If so, a nice 3.42 gear swap would be felt in acceleration with no adverse effects to drivability [especially if you have a manual 6 speed]. If you want instant pep in how the car feels while accelerating...gears, gears, gear. I'd do the intake, keep my 241 heads, spend the money saved from the 243 ported heads...and do a gear set swap. Stop light to stop light...GEARS!!!!

Just providing you with options.

 

If you CANT pass the SMOG test/inspection. Here is what I would do, Purchase a true COLD AIR INTAKE SET UP, (I have the VARARAM) Add the LS6 intake, Ported LS throttle body, GEARS and a good tune. You could purchase a used LS6 complete exhaust set up for a little better STOCK exhaust. I gave a friend my stock LS6 complete exhaust (Manifolds low mile CATs and mid pipe. ) He was very happy with it.

Is it a Automatic or manual transmission C5? How many miles on the car?

NOTE-1 If you are going to have the car TUNED, I strongly recommend starting off with a fresh set of plug wires and plugs, and new O2 Sensors.

I agree! A big cam regardless of what else you do, will be tough to tune and drive. I have a big cam and many supportive other MODs that need to be added to the list to support that cam Mine ZO6 has 243/243, 610 lift, cam, Patriot Ported Heads, Caddy Racing Lifters, FAST 90 Ported intake, 90MM ported TB, 42 lb/hr injectors, VARARAM, Stainless works headers/full exhaust, high flow cats and a proper tune. It makes 450 wheel HP.
When you go much past 400 - 420 wheel HP, you have to worry about breaking other stuff and spending that much more money. The stock A4 Transmission does NOT survive long with adding lots of power. Big Cams in an automatic require better automatic clutches and other internal mods, a high stall converter and different shift point programming. If you have a lot of miles on the car, a manual trans may suffer OEM clutch issues. and or Torque tube issues.

Make the car more fun to drive. The gears will put a big grin on your face. While you are making the car better, think about some new shocks and maybe adding a better sway bar set up if you have a base FE-1 or F45 suspension. Good used Z-51 or ZO6 suspension parts can be had pretty cheep. I used the C6 ZO6 Shocks on my ZO6 and couldn't be happier with them. They are a direct bolt in up grade and improvement on ANY C5.
I had the F-45 Optional Suspension Selective Real Time Damping on my 98 Coupe. Its the Absolute WORST thing GM ever put on a C5! If you have that mess, Tune it OUT and get a real suspension under it!
If the shocks on your car are STOCK and never have been changed, its WAAAAAAAYYYYYYY PAST TIME to change them.

Here's a suspension chart for you to look over:

http://www.c5registry.com/membersonl...uspension.htm\
BC

 

So glad I'm not the only old schooler in here.. I had a '70 Challenger in high school, one cylinder no compression, that chopped and smelled like that! I'm grateful for your input here... and am ecstatic no one has turned this thread into a boost flame-war..

I have the T56 with the stock 3:42s. Don't think I haven't already thought about dropping them down to 3.90s or more. I would NEVER do 172 MPH top speed anyway..

 

It's a convert just turning 90K. I searched high and low to find one in torch red with the black interior, MN6, and Z51 package. I have already upgraded the sway bars, end-links, and urethane bushings. It takes corners like a boss! It does need new shocks, the alignment I had done last month couldn't correct the camber on the front right, so I know it's sagging a bit.

Fortunately, the engine will be out of the car tomorrow. I already ordered an Exedy stage 1 clutch kit, Tick master, and a new GM OEM slave. I think I will upgrade to the LS2 dual roller timing chain kit and replace the front and rear main seals. While it's out of the car, I might as well do these things.

 

Define "strict smog area." If you're going to go to a stage 3 cam (stages are useless to me. SPECS are where its at.), I doubt youll be passing any smog tests. But again, where is this strict area, and can you find a decent, performance minded, car guy inspector? If you can, great. But asking anyone's stage 3 cam to pass emissions (the idle alone will be a 10 square foot red flag) is asking a lot.....

 

ALL 6 speed manuals came with 3.42 gears stock. Only an A4 would have a 2.73. Some A4 cars had the optional G92, 3.15 gears, which are better, but still not as good as a 3.42.....

 

Well, I say strict as in UHP is starting to pull over coal rollers and report the diesel shops that passed them. I imagine pulling over loud cammed cars aren't far behind. However, I do have to pass a visual. In Salt Lake County, I understand they are taking pics of the C.A.R.B. numbers on the cats. They aren't doing that in my county, yet, but if we fail many more PM10 red days, I am sure the EPA is going to tighten the noose.

You're right in that the cam would fail a sniffer, but so far we did away with those with EEC-IV. Hopefully by the time they bring them back I will have a Vintage tag..

 

This was my baseline before any mods. With just a Donaldson cold air and a Dynamax Super Turbo axle-back, I am only losing 28 HP through the T56 and stock manifolds. Not bad for a 24 year-old car!



So, based on this pull, I only need to pick up 83.3 WHP to get to my goal of 400 with the parts I listed above. Shouldn't the stage 3 cam alone put me in that ball-park?

Anxious to see any feedback here.

D

Edit: Added 36 lb injectors to the mix. Being the stock ones are 26 lb and 24 years-old, I just upgraded and won't look back.

I am really hoping the tune can make this rig driveable and still make me 100 WHP gain. If not, 3.90s might be on the way.

 

I don't know if the cam alone will get you in the ballpark. I'm thinking at least 60whp, with supporting mods....a lot will depend on the "stage" 3 cams specs. To reiterate, if you have to pass a sniffer, I doubt very seriously you'll pass. But, I've certainly been wrong before. For reference only, I have a 232°/250°, .610" lift, on a 112 LSA Futral by Cammotion cam in an LS7. Even with the bigger cubes to help "tame" the cam, no inspector worth his salt would pass my car. The idle alone, while not super radical, is far from stock. Good luck to you.........

EDIT. After seeing the CNC 243s, I was about to say I'm pretty sure you’ll make it. But now that I've read your post, and seen averagejoesautos reply about you running your stock exhaust manifolds, I'll now say no. I agree with averagejoesautos, that the exhaust is going to cork it up pretty good. Running the stock manifolds on an engine like this is like baking a great cake then shorting it in the frosting department!! This will be even worse if running the early style, '97-'00 manifolds. The '01 and up are a bit better, but not good enough for what you're doing. If you do this, it will certainly run much faster than stock. But your engine will be one of those engines you've read about that will gain 50+hp when you go to headers. My .02.....

 

So, help me apply a little logic here. If my baseline Dynojet had only lost 28 HP between the crank and the wheels, (a loss of 8.5%), and I add another 100 to 125 HP to the crank.. If the scale were linear (which I know it's not.. it's more about flow and vacuum scavenging). Even if I lost 10-12% after the mods, I would still mathematically come out with around 413, which is about where I expect to be.. Does this logic not apply? I am seeing in other posts where cat deletes are only picking up about 8-10 HP, so I am assuming based on my own dyno that the stock manifolds and cats actually do flow fairly well. The tuner doing the work said he would be more concerned with the extra flow blowing them out eventually. At 24 years-old, he mentioned that it might even happen on the dyno during a pull..

Plan B.. I am looking at buying a small chunk of land in the middle of no-where that I can drag a trailer on and stick a mailbox out front. Then I can register in some remote county and get some Hooker Blackhearts with high-flow cats. Lol

 

How are you relating a cam selection + stock exhaust to drivability? This doesn't compute for me.

 

Is there a SC kit that could meet your emission requirements? If so you might be ahead in both power and ability to pass emissions.

 

Yeah, I can add air all I want and still pass. I am actually beginning to think I should have gone down that path instead. The problem was and always has been the clutch. If the clutch had already been done, I would have pinned the crank and never looked back. But I have gone down the HCI road, and I am fighting emission issues all the way.

 

[QUOTE=grinder11;1606715342]I don't know if the cam alone will get you in the ballpark. I'm thinking at least 60whp, with supporting mods....a lot will depend on the "stage" 3 cams specs. To reiterate, if you have to pass a sniffer, I doubt very seriously you'll pass. But, I've certainly been wrong before. For reference only, I have a 232°/250°, .610" lift, on a 112 LSA Futral by Cammotion cam in an LS7. Even with the bigger cubes to help "tame" the cam, no inspector worth his salt would pass my car. The idle alone, while not super radical, is far from stock. Good luck to you.........

EDIT. After seeing the CNC 243s, I was about to say I'm pretty sure you’ll make it. But now that I've read your post, and seen averagejoesautos reply about you running your stock exhaust manifolds, I'll now say no. I agree with averagejoesautos, that the exhaust is going to cork it up pretty good. Running the stock manifolds on an engine like this is like baking a great cake then shorting it in the frosting department!! This will be even worse if running the early style, '97-'00 manifolds. The '01 and up are a bit better, but not good enough for what you're doing. If you do this, it will certainly run much faster than stock. But your engine will be one of those engines you've read about that will gain 50+hp when you go to headers. My .02.....[

So, the plan changed (again)... Everyone says they have parts, but then nothing ships and you get buckets of excuses..

Here is where I am today:

Engine is out of the car, here are the parts I actually could get:[list]

• AFR as cast 215 Mongoose heads
• BTR Stage 3 cam 231/244 .630″/.615″ 112.5+2.5 with titanium retainers and .660 lift springs
• BTR 1.7 rockers with trunion upgrade
• LS6 Intake
• Alphainjection 550cc fuel injectors
• Front and rear main seals
• Billet double roller timing kit
• Melling high volume oil pump
• New NGK plugs and wires
• Exedy Stage 1 clutch assembly
• Tick master
• GM slave
• HP tuners Dynotune
  
  Still gonna be stock LS1 manifolds H-pipe, and cats with the Donaldson CAI, Dynomax SuperTurbo axle back exhaust.
  
  Still hoping to pick up about 80-85 WHP without the headers. This would put me at about 450 at the crank, and hopefully 400 at the wheels. I am supposed to get it back Wednesday, but I think it will be more like Thursday, maybe Friday.

 

So, I got the new heads and cam installed, picked up the car from the shop last night. As I was driving home, I started noticing what I thought was clutch chatter, like maybe a throw out bearing or something. But this morning, I put about 50 miles on it, and it has gotten worse. It's definitely a tick in bank 2, probably in number 6 or 8. It's most loud at 1800-2000 RPM in 4th gear.

The lifters, trunions, pushrods, springs, valves, etc. are all new. I'm going to have to take it back to the shop on Tuesday after the holiday weekend. Do I need to park it until then? Am I damaging anything? Or is this just some kind of break-in period where something needs to seat or settle down?

Thanks for the look,
-D

 

Sorry I can't assist, but I'm curious who did your install?