Dalesc4

Hi guys

I have. Stock std 88
Just ordered headers and having a custom exhust fitted

I would like to replace heads

What do u guys recommend ?

Will also do a cam at same time

What do u guys run ?

Will the stock mainifold be enough

It's hard in Australia to get the right info

Thanks dale

vader86

Current D-port 113s are a good head, it depends on what you want from the car. Heads and cam and intake should be matched together, and which one you get depends on what you want from the car.

Dalesc4

I would like around 400hp at the wheels
It's a manual car

Thanks for any advise

Dale

Churchkey

The torque # is always higher until the engine reaches 5200 rpm & gets into the HP curve. The entire TPI, heads & exhaust are choke points, the engine basically hits a breathing wall at 5K.

113 heads have small runners + valve lift cannot exceed .500 without incurring retainer to guide interference + the valve diameter is small. Combustion chamber CC is 58. The heads need some work for bigger cam use. They are good heads if torque is the concern.

If 400 hp at the wheels is the goal you need 6000+ rpm which will require an intake, heads, cam, full exhaust & a gear. Depending on the new head combustion chamber size you may also need domed pistons to reestablish compression ratio. For a street vehicle on pump gas dynamic compression ratio should be your concern it will basically be determined when the intake valve closes completely. IE: intake valve event after BDC (the beginning of the compression stroke).