Mach 1 heads

[Ellik]

With the search button gone, let me throw this out there:

What gains could be seen with swapping unported '03/04 heads onto an Intake/exhaust car w/

1) stock '01 cams
2) Mach 1 cams
3) Terminator cams

worthwhile or not?

 

[01 Venom]

Damn if only the search button was here. Tons of info on this posted all over the place.

 

[Ellik]

I know...... and no way to get it, and I have to make up my mind in the next 13 hours if Im going to buy a complete set of heads... or not

I'll settle with the abridged version from a really smart person who read all those posts and remembers the gist of it.

 

[Torch10th]

The heads are an improvement yes, but going unported c heads to unported 03+ castings, isn't going to yield a ton of gain.

The low speed velocity is much better on the 03+ casting, so the gains you do see will be lower in the RPM range. Which of course is welcome.

The Mach 1 and Terminator cams are the same, no difference.

The 01 cams installed in the 03+ castings should keep the power in the same RPM band, or close to, as the factory 99/01 cars. Likely with a torque bump in the lower RPM's.

I would say this though. With the amount of work it takes to do a head swap, I'd almost just pickup a Mach 1 motor and do an R&R on the factory engine.

 

[na svt]

Go with the 96-98 intake cams and any of the exhaust cams (96-98, 99/01 or 03/04). These cams are used in NMRA factory stock 4v motors along with those heads and work great..to the tune of over 370rwhp/370rqtq. You won't see that in a lowere compression street motor but there are gains to be made by going with them.

 

[na svt]

The low speed velocity is much better on the 03+ casting, so the gains you do see will be lower in the RPM range.

Please explain low speed velocity is better? That makes no sense.

 

[Ellik]

^ thats what Im looking for. Thanks!

 

[Torch10th]

Please explain low speed velocity is better? That makes no sense.

Meaning the speed at which airflow passes through the heads. Flow numbers aren't completely indicative of this. Higher velocity aids in power production. The 03+ castings are better in this aspect than the c heads. They do of course reach sonic velocity sooner, but this is one of the reasons the 03+ castings make more power, lower in the rpm range than the c heads.

 

[na svt]

Meaning the speed at which airflow passes through the heads. Flow numbers aren't completely indicative of this. Higher velocity aids in power production. The 03+ castings are better in this aspect than the c heads. They do of course reach sonic velocity sooner, but this is one of the reasons the 03+ castings make more power, lower in the rpm range than the c heads.

I'm not quite sure what you meant by "low speed velocity is better"??? Yes, velocity is key to making power, especially low rpm power, but the velocity of the heads you are comparing is about the same. The difference is in the intake port design and the size of the exhaust ports.