twin ignition head temps?
 

Do any of the builders here have thoughts on whether or not using a twinplug setup on something like a 9.5:1 2.5L street engine would help reduce cylinder head temps or make the engine last any longer than normal? I understand it would be unnecessary, but would there be any benefit? Would it make oil temps more manageable or make the car run better on regular pump gas?

TIA

Hi Shuie,

The timing reduction would lower cylinder head temps by lowering cylinder pressure BTDC. The lower cylinder pressure would also guard against detonation.

It will also give you a wee bit more power because you can run less advance.

I would love to twin plug the2.5l in my 914/6 ... but is the expense worth the gain? Maybe 5% more hp? What is the overall cost? $3k ish?

I doubt it would be 5%. Maybe 1%. The real reason to do it is to allow for higher compression ratios (which on an old 911 requires a high-domed piston), which will make more power.

Its more than 1%, all things being equal.

The gains transcend just BHP,.......you get improved throttle response, improved drivability, and lower cylinder head temps (which on a hot day, help VE's).