righto, i have just purchased a cobra inlet manifold, some gt40p heads, and some underdrive pulleys. Which i am quite bloody pleased about, as ive been wanting to get them for a bloody long time now.

anyways....

What will i need to fit these, obviously gaskets for each head, gaskets for the manifold, but is there anything else i will need to get or anything else that i will need to replace in order to fit these items? as in different bolts for the heads, different bolts for the manifold etc..

Also wanting to know if the standard throttle body will fit onto the cobra manifold? i will be upgrading to a larger one in the near future, but not quite yet. What sort of size would people recommend for this setup?

And with the underdrive pulleys, what exactly is required, i have never really looked into it that much. Is it just replaceing the standard pulleys with different ones?

And for the last question, headers for the gt40p's. Can you fit headers designed for the E7 heads? i have read somewhere that you cant, and somewhere that you can, so im just wanting to clear that up.

I think that is it. If you could help me out with these questions, it would be muchly appreciated.

Cheers

BEN

Some say use new head bolts whenever you take the heads off so you could spend some more money there. Also use 90* plug leads to clear your extractors but you may need to either bolt in the 2nd plug on the pass side before you fit the pipes or make a skinny socket to clear the pipe if you choose to fit the plug after the extractors. 65mm throttle would be a good upgrade too. Underdrive pullies are easy peasy to fit.

If you need a hand fitting all this jazz on your Fairlane, drop me a PM as I only live at Kurri.

Don't go bigger than 65mm for the throttle body.

How many underdrive pullies did you get 2 or 3? Should have gotten a crank, alternator and waterpump pulley. It should be a matter of just changing em over.

And headers that fit E7's will fit gt40ps, just the clearance of the sparkplug due to angle is a pain.

Yeah i was thinking to change them, but are they all the same size as the ones on the E7's? And are the bolts on the manifold the same saize as on the HO manifold?



I have genie extrators to fit the E7's ready to go on, but you saying that the leads may come horribly close to the extrator pipe on one of the holes. Hmm might be better off getting different headers to go on, i really dont want to be having issues with burning leads etc.... The extractors that suit the gt40p's are off a AU series 3, yes?



Yeah thought as much, its just a direct replacement as far as i have heard.



Actually i only got the street series, the one with the crank and a shorter belt. i actually didnt even know there were two types untill you rought it up. Do you think it would be a better idea to get the race series instead, as i still have time to stop the order?

Also got a 1" spacer for the cobra manifold. The question is will the manifold fit under the bonnet with it fitted? and what will it exactly do?

au extractors will not fit on your car they will foul on the K frame mount next to the shock tower. Plug angles from my experience aren't anywhere near as bad as people say. I have GT40P's on my LTD and i run hi-tech headers designed for e-series and they couldn't fit better, i also run 45 degree plug boots not 90 and have had no problems. I just had a set of top gun 8.8mm custom leads made a little longer than normal to fit my billet ignition lead covers and i got them made with a 45 angle not 90 on the boots as in my case cleared the extractor much better.

hi mate, well done on the parts purchase, youll love it when she back together.

prety sure you will need new bolts for the cobra manifold, same as explorer i think. ive been told that a 1 inch spacer wont fit under the bonnet but i havent tried it but in saying that you should have got new longer bolts with the spacer so if it clears the bonnet you should be right for bolts. the spacer stops heat transfering from lower half of intake to the top half of the intake and also makes the intake runners longer witch will help it make more torque. with the cobra manifold you wont need your egr spacer as the cobra has inbuilt egr and t/body should be a straight swap, i think. as for extractors you should be right, its a tight fit but with some 90deg boots and some heat tape you will be fine. with the pulleys you said you could stop the order? i would, and get the race kit for $280 odd last i looked, alt, waterpump and crank pulley, makes a nice lil diference on a stockish 5ltr. prob the only other thing i can think of (at this hour of the morning) would be upgrading the stock maf as this will now be your biggest restriction along with the stock t/body.

Nice selection of parts you have there mate. Should make for a nice improvement over what you have now.

With the cobra manifold you may need new plenum gasket(s). One if your not running the spacer or wou'll need two if your are going to run the specer. Also if the bolts that come with it to join the upper to the lower are to suit the 1" spacer you may need to source some smaller ones. I reccomend using a Fel-Pro 1250 intake gasket set to fit the manifold. As far as clearance goes with the spacer, just get the lower bolted down into place then just check clearance to bonnet with the spacer and upper plenum just sitting there, some playdough ontop of the plenum will help measure, personally i think it'll be too close so you may want to swap it for a 3/8" or 1/2" one or run without it.

The heads should bolt on fine. I do reccomend going for a new set of head bolts/studs like a set of ARP's for some added insurance. Headers shouldn't be an issue, just check clearances as they go back on. If its too tight, i know "schnoods" runs Advance headers which are made for GT40P's onto e-series. I can tell you though that extractors made for AU will not fit e-series due to steering arm clearnce etc.
Aong with these heads i REALLY recommend going for a set of Yella Terra 1.7 roller rockers to get a bit more lift out of he stock HO cam. I have heard of some nice results in doing so. Will make for a nice torquey combo. Will make the whole job abit more worthwhile.

Underdrives i would cancel the order for the street series and go for a set of the race series ones. As said this is the 3 piece kit and maintains stock belt size. Used these on my ute when she was pretty much stock and found a nice improvement.

As far as throttle body goes, you will be best off running a 65mm unit. The stock t/b will be a major bottleneck with this set-up along with the MAF. Let me know as i have a 65mm T/B and matching EGR spacer here of an AU XR8 that i am willing to part with.
With the MAF you may be able to pick up a larger housing (70/75mm) from an AU XR8. These can be fitted with no-tune and some people have done so successfully but others have ran into lean issues. Best bet is to try one out but have your car on the dyno to have AFR's checked out in all conditions. Only other option is to have it tuned with the larger MAF then an upgrade to larger injectors would be the go. This would get the most out of the combo.
But in saying all that, you will still see nice gains with that combo with still running the 55mm MAF and 19lb injectors.

Without turning this into a catfest, why do you guys not like the street series pullies? "Race" pullies have 3 pullies with the standard belt so that you can run your car in traffic without the thing overheating on idle and so that your alternator can pump juice back into your battery when you have a mega stereo running whilst the motor is idling. They still underdrive your accessories the same.

Street series will work the same greyskull. Keep the difference and use it for a larger throttle body and then MAF. Remember to keep the card you get with the shorter belt so that you know the size when the time comes to replace it down the track.

okie dokie...

I have cancelled the order for the street underdrive's and will be on the look out for the race series (either second hand or brand new). A lot of people have told me to go the race series instead of the street.

But what i will need to know is, if the manifold with the spacer will fit under the bonnet, i will check it out when i get it, but i just wanna know if it will fit before hand. I have been told the cobra and 1" spacer will fit under a EB/ED bonnet, so just wondering whether it will fit in the later e series. i cant see thier being too much difference.

And pardon my ignornace, but i havent really looked into it before. but what will aftermarket roller rockers do for me. Are the Yella Terra 1.7's the best way to go, and what sort of price can you pick them up for? as i think old mate who im buying the manifold off has some for sale aswell.

And for the last question for today (i think anyways) where is the best place to buy new head bolts/studs and manifold bolts from? Someone befroe mentioned ARP's? is that a brand or a shop that sells them.

Cheers

BEN

roller rockers put less strain on the valve springs and such, but personally with the setup your going to have i wouldn't bother but i dare say most people on here will suggest to do so. I've done a touch more engine work on mine than u intend on doing to yours and i haven't got yella terra roller rockers or anything like that and i haven't had a problem so far. They are an expensive bit of kit to.

Definately go the YT 1.7 roller rockers.
The main improvement for your setup is that the 1.7 ratio rockers will provide a tad more lift over your stock 1.6 ratio ones.
Works nicely with the stock cam.

ARP is a brand, can get them through Rocket Industries or pretty much any performance shop.
Rocket are generally pretty good pricewise, I'd lean towards going direct through them, chase up the part numbers for them off Summit or something and fire rocket an Email for a quote.

The roller rockers he has for sale are the FMS 1.7 roller rockers. Are they just as good as the yella terra ones?

STeady, i shall take your advice and get them through rocket, sounds like a good plan!

Cheers people, this is muchly appreciated.
Im sure there will be more to come though

The FMS rockers are made by Crane USA. Have a look at the part numbers and when you get them, post it up and I'll look in my FR catalogue to see if they fit under your pressed steel rocker covers.

I have been told taht they will fit, but unfortuantly i wont be getting the roller rockers, as he wanted a tad too much for them in my book.
I will invest in some r/rockers when i purchase the heads in a month or so. probally get some nice rocker covers too

It should all becoming together nicely soon