Replacing N/T 4G63 head with Turbo 4G63 head; should I swap cams?

[JusMX141]

I'm replacing the head on the 6-bolt 4G63 in a customer's 1G Talon non-turbo with one from a '95 Talon TSi. The engine is getting a full rebuild as well- it has nearly 200k on it.

I'm already well aware that the heads are interchangeable; my question is would it be wise to swap the non-turbo cams into the turbo head to keep the non-turbo cam profile in the car, or should I leave the turbo cams in the head as an "upgrade"?

I believe the higher lift of the turbo cams would probably move the powerband to the upper end of the RPM scale, but I'm not sure if it would make the car undriveable or not (by taking away too much low-end torque.)

If anyone has done such a swap, feel free to chime in.

 

[1_2befast]

I don't know how to verify it, but I think the N/A cams are actually more aggressive.

 

[bento]

The turbo cams are more agressive than the non turbo cams. The duration on the turbo 1g heads are 256 both intake and exhaust. I believe the duration of the non turbo cams are somewhere in the 240 range.

 

[JusMX141]

After month's worth of research and interviewing the correct individuals, I found it best to stick with the non-turbo cams.

While the intake cams are nearly identical between the two engines, the exhaust cam on the turbo engine offers far less backpressure as it's designed to be used with the turbo creating more backpressure than the non-turbos exhaust system will yeild. The result would be a loss in low end torque, which is not what my customer wanted.

You're a year too late, guys. I forgot this thread even existed.

 

[Tyeler18]

wow talk about a dead thread

 

[jmss123]

Hi, a friend has a 4G63 Turbo 6bolt 1g engine with bad head, he is kind of short of money and wants to know if he can use a NA head from a 6bolt engine that he found in a junk yard really cheap, so if someone here knows something please help.

 

[jrohner]

Hi, a friend has a 4G63 Turbo 6bolt 1g engine with bad head, he is kind of short of money and wants to know if he can use a NA head from a 6bolt engine that he found in a junk yard really cheap, so if someone here knows something please help.

The turbo and non-turbo heads are the same. The cams also are said to have the same duration, it's just that the lobe separation is different making the overlap different.