So here we go mods this is round 2 on this one since i lost the first one.
This is to help new LS1 guys just coming into our forums as a guide with basic bolt ons both cost and performace results. I strongly recommend for every one to do their own research and find out what works best for their set up.
Lets start with the disclaimer. First off no two engines or two cars are a like, results will vary. This is only to act as a guide for basic bolt ons, other supporting mods may have direct results on performace and durability.
As i am sure you are aware by now you own one bad %$! engine. Unfortunately the rest of the drive line is not so lucky. Please read the following Notes and plan your build accordingly.
M6 (T56 6-speed) guys are a little bit on the lucky side with a very strong and sound 6 speed. The transmission with a good clutch can handle a good bit of power and should be sound up to the point where you will need to start building the bottom end of the engine.
A4 (4L60 4-speed) The 4L60 is a good bit weaker then the 6-speed cars. All it takes is a good set of sticky tires and a good stall converter can destroy a stock 4L60 even under stock horse power.
10-Bolts are crap. If you plan on doing any real mods start saving up for a 9 inch or a 12-bolt and save your self a lot of pain. The A4 cars are a little less harsh on the factory rear then the M6 cars tend to be. However even built 10-bolts have been known to fail by bolted cars.
When starting to take on any project it is important to keep in mind your end goal. For example building a high CR (compression ratio) engine when you are planing to go FI (Forced induction) in the future.
1. (Lid/Intake) $150-$250 5-8 RWHP
This is a great first mod if you are the lucky guy that just picked up a stock LS1 car. The factory lid was designed to drown out sound from the intake system. Upgrading your factory Lid/intake and Filter is cheap and effective first mod. SLP and Whisper both make good lids and vortec offers a two intake designs for the F-body.
2. (Cat Back) $250-$1000 4-12 RWHP
This mod is more for sound then performace. The factory cat back exhaust does a fair job of moving air out of the engine. If you dont want to spend a ton of money most exhaust shops can hook a F-body up with a custom Cat-back for around $250-$350 bucks. Bolt on Cat-Backs can be a little pricey, ranging from $350-$1000.
3. (Y-pipe) $180-$400 8-18 RWHP
This is where the money is in the exhuast system. Catless Y-pipes run around $200 and can add a nice little tone to your factory exhaust. If you live in a area where emissions are critical then a Y-pipe with high flow cats is still a great mod and can still net some good gains.
4. (Intake Manifold) $300-$800 12-17 RWHP
A very good and simple mod there are a few options out there. The LS6 manifold is a good upgrade over the factory LS1 manifold. People have reported 7-12 RWHP. you can pick up a used LS6 manifold for $300-$350. The FAST manifold is a good upgrade as well but it comes with a hefty price of around $800 for a little more flow over the LS6 and will show about 17 RWHP gains on well bolted cars. I PERSONALY recommend staying away from the BBK and Warrior intakes as they tend to heat soak and not breathe as well as the LS6 and FAST do.
5. (Headers) $350-$700 12-18 RWHP
This is a nother great upgrade. The factory manifolds are good but there is room for improvement especially as your air demads increase. Headers can also add a little deeper grow to your exhaust system. When buying headers it is very important to factor in the cost of installing them. If you have owned you car more than a day then you have noticed you dont have a lot of room. This is not a job for the non-mechanically inclined. Most muffler shops charge around $400-$450 to install them on a F-body.
6. (Valve Springs) $180-$280 3-7 RWHP
Its no secret that our factory springs suck. Even at 6000 RPM's the factory springs are about at there limit. Most people will only see a one or two horse power gain at the wheels. This is not to underplay the importance of this mod. If a factory spring should fail and cause you to float a valve you could be in for a heavy repair bill. This is a mod that i recommend for just about any one that plans on doing any real mods or has a few good miles on their car. This is a must for cam swaps and guys that plan on turning higher RPM's.
7. (Dyno Tune/Hand Tuner) $250-$400 10-25 RWHP
This could be one of the most under played mods of all time. We are lucky to be able to retune our factory computers to do some amazing things. HP tuners is a great option at about the same cost as a hand tuner it is no where near as limited and can handle almost unlimited tuning freedom. You will have to have a good LSX shop tune in the car so be prepared for the additional cost. Most shops charge around $400 this normally includes the inital dyno tune and additional tuning that may come up from future mods and is by far the best way to get the most out of your cars computer system. Now on to the hand tuners. GM high Tech did a shoot out on hand tuners a few months back. They found that a near stock LS1 would gain on average around 15 peak RWHP and about the same torque from just a simple tuner. What is more impressive is the tuners picked up power every where in the power band.
8. (Cam) $300-$500 20-70 RWHP
This is the holy grail for the LS1. Cams produce huge power gains even from small hot-cam. The one down side to cam swaps is the additional cost. Most shops charge around $350-$450 for the swap. With any LS1 cam swaps valve springs are a must and a re-tune may be needed depending on the size and lobe of the cam. I also recommend hardend push rods for added security. The pay off can be as much as 40 RWHP on a mild very drive friendly street cam. One thing i can not stess enough the need to do your own research and find what works best for you. I PERSONALLY recommend mild cams over huge lugers. Making power in the Low-Mid of the power band where you can use it can make for a much more enjoyable cam.
9. (Throttle Body) $180-$280 1-3 RWHP
This is a good budget mod. You will not see any large power gains from your TB. Dyno test show little to no gain. The positive is you will notice a small increase in responsiveness. Note that supercharged and Small Turbo guys will see no improvement on stock bottom cars.
10. (Mass Air Flow meter "MAF") $200-$350 HP-NA
This is one mod that i PERSONALLY feel is a waste of money. Many experienced LSX tuners will agree the factory MAF is able to support more power then your stock bottom end can handle. Aftermarket MAF's can cause tuning issue and are prone to fail. The stock unit is good to well over the the 500 HP mark where some tuners switch over to SD (speed density)
11. (Fuel Rails) $150-$300 NA
Your factory fuel rails can support more HP then your stock bottom end can handle.
There is no substitute for good research. It is important to get imformation from multiple sources and find out what works best for your application.
Tuning is critical major engine damage can accure with out proper tuning. Having a good shop that knows what they are doing goes a long way to securing the durability of your engine.