righto along with the shaker mod, I think I've got enough in the budget for a set of heads and manifolds, I'm playing with my EF V8 by the way and have enough background ( aircraft and deisel technician trades) to do it myself, just no idea of cost, I'm not going silly just want tough and drivable.

So after my limited research can anyone give me a rough guide as to what I'm up for price wise to get,

- a set of GT40 heads S/H or new (if they are what I should go for or is there better/cheaper option) they will be port and polished,

- AU Explorer upper and lower manifold (again is this what I'm after or is there better/cheaper option) and

- a 2031/2030 cam (which one is best for street driving),

- as well as a set of roller rockers and new lifters (still hydraulics ?) and

- is it worth investing in a set of cam gears vice the chain and sprockets.

and is there anything I have missed in the top end, I've already done the MAF and TB,

Rough Prices for you:

GT40Ps - $1000
Manifold - $1000
Rockers - $450
Cam - $500-700 (the latter as you should get new springs)

GT40P's are the heads to look for and wil cost $1000-1200 2nd hand, they are fitted to all AU V8's so they are relatively easy to find. They probably don't need any porting but if you can get it cheap or do it yourself then you may as well while they are off.

For the ntake, again look for the AU Explorer manifold, should cost around $600 2nd hand (maybe cheaper if you can get the heads and intake together).

The 2030 and 2031 cams are pretty similar, 2030 is a bit more agressive and uses 1.6 ratio rockers while the 2031 uses 1.72's (I would go the 2030). Shop around and you should be able to pick up the cam for around $400-450. You will also need to upgrade the springs and retainers so add another $200-$250 for them.

You don't need new lifters, the 5L windsors use roller lifters which really dont wear. It is a good idea to dismantle them and clean them out while you have the engine apart though. Also don't go for a gear drive, a decent rollmaster double row timing chain is all you need.

What injectors are you running? If they are still the stock 19lb injectors you may need to look at an adjustable fuel pressure regulator to bump up the pressure a bit, otherwise you will probably find you will be leaning out up high.

thanks guys, bit steeper than I thought, it's been a while since I rebuilt an engine, I guess being a later model than I used to play with doesn't help.

question on the fuel pressure, will the stock pump handle upgraded injectors and I suspect I need to get the MAF looked at as well.

My stock pump maxed out at 180rwkw but some have got 220+rwkw out of theirs. A Walbro 255l/hr intank pump will only cost around $200 and flows enough for 600hp. And yes you will need a new MAF if you change injectors, C&L are the only aftermarket MAFs available at the moment and have interchangable tubes to calibrate the meter for different size injectors.

I've already got a 70mm PRo-M MAF from MrLandau , but it's calibrate to the stock injectors, is it easy enough to re-cal them?

Because they are only recalibrated in the US it often works out cheaper to buy a new one, although Pro-M have gone out of business and the company who has taken them over isn't producing MAF's yet. You may still be OK with the stock injectors, you can get 160-180rwkw out of them and with your planned mods you will still be around that power level. You will need an adjustable fuel pressure reg to help out at full throttle though.

hey wow im going thru almost exactly the same steps... and am wondering the same things... i probably will get a new timing chain, and if im not too strapped for cash i'l even get a highflow/more efficient water pump(edelbrock make em)..

thing is, i havent done MAF/TB yet so i'l be getting an edelbrock 70mm TB and C&L 73mm MAF calibrated to 19# injectors, and lata on i'l get an adjustable fuel reg, bigger injectors, and tweecer all at the same time to tune it all in properly(so that the ECU gets the right LOAD values).

i DO however have a set of GT40p heads and il be porting the exhaust side a bit coz theres lots of room for improvement there.

and as far as manifold goes, i'm going for a trickflow/edelbrock one.. much better than explorer.. and easier to get than what i really wanted, - a GT40 tubular.

as far as cam goes, i'l probs get a crane 2030 too, with all the appropriate valve train gear...

The US pumps don't fit the aussie cars as far as I am aware, different leangths. But you really don't need anything better than stock, even on extremely modified engines they still keep them nice and cool.




You can't take much material out of the heads because there are coolant passages extremely close to the surface. There is a bit of room for improvement in the GT40P's but unles you are running a stroker you won't see all that much difference. If you can get it done cheaply, then go ahead and you will be a few kw ahead.



Again, the aftermarket intakes do flow better but don't give huge results unless you are running stokers etc. The guys in the US are getting very similar results with the explorers. The trickflows and edelbrocks are quite reasonably priced these days so they are still a good option, but if you find a cheap explorer around the place you can save some money and get similar results.

ah ok that writes that off then...



ah ok... stil tho, from looking at the port itself then the marks from wherethe gasket was, theres lots of material... aswell as that the GT40ps are known for, aswell as GT40s and E7s for having a restrictive exhaust port.



yeh thats it i probably will be going stroker lata on down the track... plus i want the prettiness of a new manifold... but if a cheap 2nd hand explorer turns up i'l get that.. till then i know a cheap trickflow thats up for sale so i'l chase that.

If you dont want to do a computer change, or a new computer to tune, you will need to source an ELII intake that hes the EGR in it, so as to run all of your standard electronics. Not sure how they run disconnected.
AU's have no provision for EGR at all.

You can run without the EGR but they are more likely to ping, if that happens you just have to back the timing of 1 or 2 degrees.

This step that your talking about is there for a reason, so DO NOT port match your exhaust ports. The step helps to prevent reversion back in to the cylinder on overlap. You can change the tune of your motor by where this step occurs between the header and the port. I assume that it occurs on the top of the port similar to the 6's as this due to the nature of the bend in the headers helps to build a better bottom to mid range torque.

i didnt know that...

but ok ill take ya word for it.. makes sense.

il still be porting the heads a little bit... only costin me a couple hundred anyway coz its not gonna be a big super accurate job, and ill probs stick with std valve size etc too.

I can highly reccomend the RPMII manifold by Edelbrock. This manifold alone gave me .5sec and 3 mph on the quarter with my basically stock 5.0 on NOS.
Brett