Anybody done it?

Did it make much of a difference in power?

At what RPM range, just the top end or mid and low too?

Thanks in advance, Rich

I don't have the thorley, I put the calmini on mine and didn't notice any power gain at all. Shoulda stuck with the stock manifold and the 2 inch exhaust, oh well, it looks better than a rusty manifold, at least [img]images/graemlins/smirk.gif[/img]

Here's my situation:

I have a Thorley on my 1.6 8V that was on my 1.3. The Thorley and a 2.25" exhaust really helped the 1.3 but I am not able to tell you about the 1.6 improvement except by re-using the Thorley I was able to save some money.

Overall, the 1.6 swap is an improvement...

Same as Ack.... I did have it on a 1.3 and it made a sizeable gain, allowing higher top end and quicker throttle response. On my 1.6, I don't have a baseline to compare to, but I'm sure it would have come close to the same results.....
In my opinion, a header is worth it.....

Most of the time headders improve the top end - scavenging effect, sometimes even hurting mid and low end.
The Japs did a pretty good job of optimizing the exhaust for overall performance already.

I have the stock manifold on the 1.6 8V now, and want more low/mid range "poop" for crawling purposes.
Even with the low crawler t-case gears and 5.12's I find I'm pulling it about 2000 RPM. I'd like more twist.
That's why I asked. I was hoping that simple mod would help.
Thanks

Try using a higher back pressure muffler , the increase in exhaust pressure will somewhat lower the torque curve . Some engines it really helps....
Sarge