23 replies to this topic

[TerrA LX]

You are not supposed to change anything on a ADR 27a motor... but... Brock/HDT got away with alot (altho how much was actually was legal is another debate re; Holden split)

Aside from keeping everything in place ie; manifolds etc you are open to cam/roller rockers, compression and porting if not too excessive.

[REDA9X]

Easiest way to make power is make it breath. Extractors and an open aircleaner is pretty simple and cheap and no one will look twice, especially if you turn up to rego checks with the original aircleaner fitted. balancing makes a massive difference too.

[axistr]

My Hatch has a 383 S/B and I had to get a polution test on it when I got my engineers cirtificate for ADR27A, I was a bit concerned as the engine is running a 288 duration cam .525 lift, 780cfm Holly, 195 inlet runners heads, extractors, 10.6-1 compression, and to my surprise I killed it and by a big margin. I carn't remember what the exact figures were but you can build high performance engines to comply you just need to plan out the engine components well before putting it togeather.

[ReplicarSLR]

Easiest way to make power is make it breath. Extractors and an open aircleaner is pretty simple and cheap and no one will look twice, especially if you turn up to rego checks with the original aircleaner fitted. balancing makes a massive difference too.

yep soon as you have put it over the pits, flip the standard aircleaner lid upside down still seals around the aircleaner element but doesnt seal on the lower part and allows air to be drawn in all around rather than just through the snorkel. If you get pulled over just play dumb if they pick it and say, 'oh I didn't realise it was upside down' and flip it back over then and there...LOL

[yel327]

The standard inlet on an ADR27A 308 is one of the reasons the HX engines are so poor compare to a HJ. They are the same 9.7:1 bottom end and heads are very close apart from the EGR ports. The cams are retarded too.

Apart from exhaust, cam and mild head work as already mentioned there is something you can do, and 2 x ways to do it:

 

1. Fit a KC 25308 inlet, these are pretty good and modelled off the blue HDT manifold.

2. Change to a pair of blue/black heads, either stock or with some mild portwork and fit a HDT manifold. Even B cast heads if you can find them.

 

Run a street grind (even a HDT grind) cam, set it up properly with adjustable timing gear. Get a HEI dizzy and graph it to suit. Get it tuned.

 

You can fit extractors, but the stock manifolds with a good exhaust work OK if heads are standard.

[tuxedoss]

So what's the difference between a HJ and HX inlet manifold that makes such a difference.

[TerrA LX]

^ yeah all that EGR crap was a load of bullshit back in the day, not much has changed, that last holden V8's didn't even have it.

[yel327]

Here is a manifold:

http://www.ebay.com....c#ht_114wt_1170

[yel327]

So what's the difference between a HJ and HX inlet manifold that makes such a difference.

 

The way they flow. Early ones are good, almost as good as a Performer. Later red ones are dogs. Here is an old Street Machine article from the early 80's. What it tells you is the stock red ADR27A manifold is severly restricting flow, and you won't get much benefit from better heads or cam. The early manifold or a Performer is capable or much more so you can achieve better results with a better cam and maybe some mild head work.

Attached Files

•  Performer003.jpg   164.4K   8 downloads
•  Performer004.jpg   136.04K   4 downloads

[yel327]

You don't need EGR on a manual V8 ADR27A car, only autos had it. The newer Performers have the provision for it I think.

[yel327]

For the pollution red one that'd probably be close to correct.

Edited by yel327, 23 May 2013 - 07:34 AM.

[rexy]

Just build what you want. The chances of being pinged for a pollution issue are virtually zero unless you aggravate the authorities by driving like a tool.

[yel327]

The car will have to pass annual rego inspections in NSW Rexy.

[rexy]

Are they really that picky?
My experience in Victoria the police state is that the authorities really don't care about emissions stuff on cars from that era. Neither the RWC bloke or the vicroads inspection nazis made any comment about the multiple missing emission components and non compliant add ons the last time I registered a car.

[yel327]

It depends who does it. Some wouldn't have a clue, some have been stung by the EPA knocking on their door after defecting a car a few days after it passed a pink slip so are picky.

[rexy]

Funny story.
Got interviewed by a senior member of the EMBONA armed robbery task force the other week.
Was pulled by a bloke in plain clothes in an unmarked car and directed to pull over into a side street.
Thank god it turns out he was a fellow hoon and merely wanted to chat about the car.
Now interestingly he wouldn't have realised what exactly was missing and clearly that wasn't his focus.
The amount of polished metal produces enough glare to hide the finer details anyway...

As always a friendly and intelligent response kept the interaction on an even keel.