S1 and S2 block and heads are not the same.

Aussies never improved the S1 L67, because they never SAW one. They only have the L27 for Series 1. Let'* not confuse the issue here. The Series 1 L67 is virtually unknown to them.

Without changing ANY internals on my engine (on the SSEi), I was able to improve on the factory components (porting the LIM, TB, SC, and EM'*) and achieve the same level of performance as a S2 L67 with PEM'*, 3.4" pulley, and PCM. But I STILL am capable of beating the likes of BoneEvil and SilverBullet (not to mention CueBall) off the line and to the 60' mark, even though all 3 of those cars are in the 13'*. Even on the best run I ever had in spite of my lake of traction, I beat CueBall to the 1/8 mile. There'* alot more potential to these S1 L67'* than most people give credit to. Now you have to ask yourself:

Do I want power for everyday city driving, lane changes, sprints off the line, OR:
Do I want power for freeway passing.

The S1 will excel on the first scenario. The S2 will excel on the 2nd.
You can MATCH the freeway passing potential of the S2 with a S1 with some hard work, but it won't cost you as much as you think if you're willing to cut some metal.

(and they all have valvetrain work, and I haven't even touched mine yet).

ya and that is another point that i would like to make......Bill has the 1/4 mile time for a S1 right now....and did it with a LOW COST....that is what i like the most, i dont have lots of cash to dump into my cars, and Wren has done this with the least cash possible, and made them stout

Let'* simplify this:

Series 1:
Built for stoplight to stoplight, or the first half of a 1/4 mile race.


Series 2
Built for freeway passing, or the second half of a 1/4 mile race.

It really is that simple.


BOTH can be improved for the price of gaskets and some attention to detail on factory components.

sooo who is gonna make a Series 1/2

WOW, there'* some: going on by Pat!

give me boosty'* car,the zilla and a torch and i'll make you a series 1/2

In a sense, I'm close to a S1/S2 hybrid already. I've already converted my Gen2 L67 to a Gen3, and improved my top end to better than that of a stock S2 (but not quite to the top end of a modded S2 top end).

My next changes to the Gen3 M62 and LIM this winter may drastically change that.

if you give the S1 top end like the S2, i will love you forever....in a strong man love of course

The statements of stoplight to stoplight (S1) vs freeway (S2) are true, however they're not worldy different. These are marginal to small differences IMO, relative to eachother you're fully correct. Both are built to have much more torque and not rev a whole lot compared to the "norm" these days.

The S2 has the aftermarket down, you'll never run out of things to do to the motor. The S1 has a few parts in this country, but things like the roller rockers are much more conservative (.12 jump in ratio vs the .3 for some S2).

Headers would benefit a series 1 car, i'm sure of it. However, as stated before, our manifolds are a great factory design and have a huge flow rate, but they're still not setup to scavenge like a true header. I'd love to see someone get some headers built, and increase their upper power without killing anything low. My other understanding is that the valves are very close in the S1 heads, this makes enlarging them very difficult.

However some of the biggest advances have come recently thanks to a lot of work through folks like Bill, etc. If you'd like to do a lot of work yourself, and dig into the unknown, i'd suggest the S1, if you'd like access to a lot of part options, including bigger SC, turbos, large TB kits, etc, then go for S2.

Having owned both. I prefer the S2.

S1 had plenty of rubber burning torque, that is true. The PCM is unrestrictive and Bill, you are running a chip.

The S2 has the power, please..don't doubt that an S2 can spin tires etc as good as an S1, however the PCM is extremely restrictive to protect the transmission.

While Bill W has made great improvements to the S1 and it has shown impressive numbers, the amount of air being pushed with the 2.0 pulley versus the 3.4 I was running, the CAI vs my gutted stock airbox, fresh transmission vs my 165K bone stock, fully ported and polished intake vs never touched....and the list of inequities goes on. My point is not that much more work was done on Zilla, however we should factor things in on an equal basis if one wants to compare power for power S1 vs S2.

Meanwhile as I ramble on, I would steer a person toward a S2 97+ car. Mods are more readily available, lower cost if you aren't planning on cutting metal yourself and more power can be recognized for lower dollars.

My butt dyno stock for stock says S2 is the way to go for me. Hey...I own an S2