Heads and Cam Decision

The mods already done before the heads and cam were chosen were, long tube headers, new clutch which should take the extra power, intake manifold to help the engine breathe better, k&n air filter, different air lid, debaffled the WS6 hood, better fuel rails, injectors and pump. So can give the engine plenty of fuel, so nows the time to get more air into the engine. Its okay having a way to get more fuel in, but without getting more air in you wont get more power.

I have got a WideBand Oxegen sensor (WBO2), from Thunder Racing, this will let me know how lean or rich I'm running, without this you cant really do Wide Open Throttle (WOT) tuning safely. If you run lean at full throttle things will start melting.

The best way to choose the heads and cam combination is to choose ones that work great togeher. I got mine from the WS6 Store in America, the heads and cam are made by Patriot Performance, which I've heard great reveiws from them on www.ls1tech.com their mane guy is called Gunnar and regularly appears on that forum.

The heads and cam combination some with fancy coloured rockers which you wont see but I know they are there :O). Also had to get longer than stock push rods, 7.450" instead of stock 7.400" this is due to the base circle of the cam being smaller.

The cam spec is 226/226-112LSA 0.585"/0.585" so this means it has a duration of 226 degrees measured when the liff is over 0.050". The 112 is lobe seperation, the lower the number it tends to sound more like a lumpy old school car. I think stock came is 119 LSA. My aim was to sound like and old skool muscle car.However you can have hude valve opening times and huge overlap low LSA but it wouldn't be emmisions legal. The cam i choose has 2 degrees and is border line on getting it throgh emmisions, but I'll come to that when it goes in for its MOT/emmisions test.

How do I extimate power gains, well I purchased some software called Dynomation this was sold by Crane Cams. This software give you a good idea of what to expect from your mods, you do have to know flow numbers, exhaust length, cam duration, size of valves. Took a little while to get all the figures in for the LS1 engine, it came up about 380hp and 390ft/lbs tq. So how did i verify this, well I also have a Gtech meter, this measures G-Force/ Accelartion, and can also work out your HP/TQ, this came up with very simular numbers. So although I wont take it as exact figures but if it says 400hp, I would expect something around 390-410hp.

So what power gains can you expect from just the cam? Well it will depens on your other mods, if air cant get into the engine or you exhaust dosn't flow too good then the cam wont be working at its best.

Here is the stock engine with all my bolt ons:-

Here is the same engine with just the cam fitted:-

Well that does show gains, I wouldn't run that cam in the stock heads for long as the valve lift is too great for the stock valve springs. Thats why I chose some heads too. Lest soo what we get with the addition of shiny heads from Patriot performance, the flow numbers for these heads are published on their website.

Expected performance from All the bolt ons, Patriot Stage II Heads and Cam 226/226-112LSA 0.585"/0.585":-

A nice 120hp gain. 520hp/480tq at the flywheel.

Heads and Cam Installation

The heads and cam arrived around Feb 2007, its taken some time to find the time when i could take the car off the road for a week this ended up being around the 10th Aug 2007. Also nersious about doing the job. I did use a reference guide from LS1 How To this was extremly helpful. It estimates about 20 hours to do the job, allowing 2 hours to take off the intake and fuel system on the top of the engine. Well I knew I can do that in about 30mins as done it many times before. Hopeing everything else would go as well. However we did have some hurdles along the way.

I used my freinds garage. Ron's at Insane Creations, its fairly local in Denmead, about 2 miles away from home. Booked it in for a week incase anything went wrong, was hopeing the job would take 2 days. There was a few long nights, but in the end we got there, took from Saturday till Thursday to complete.

First the radiators came out, in the guide it said you can leave the air con connected and move the radiator when you slip the cam in and out, but due to the pipes being aluminum we wernt too keen on the idea incase they breaked. This time of year I dont use the air con anyway, so we desiced to take it all out of the car.

Its amazing how much space there is in the front now without the radiators. I can stand in the engine bay once again like I could on my '89 Firebird 2.8L V6, the space on that was due to a missing couple of cylinders.

Intake came off nicely. I did have my F.A.S.T LSX intake on the car for some time, but I took it off to port and polish it to match the ports on the heads. While this was off my car Tony from the car club sprayed it for me. A nice metalic blue. So the one that was just coming off the car was the stock one.

Pulley wheel came off okay, then undone the bolts for the timing gear. The old LS1 timing chain was a little slack, but then I dont know if its ever been changed, this engine is 130k miles old. This dosn't have to be changed, but it was advised so new oil pump ported and polish from SLP was going in aswell. This was some of out time consuming problems.