304 extractors?

[v8commy]

do extractors make a big difference or are they just talked up to be more effective than they are ie replacing headers with extractors would it make a huge power difference? and has anyone used a certain type of extractor in a 308 injection top conversion in vk? as ive been told standard headers fit good but will i have problems with aftermarkets?

 

[jimmyd17]

i had pacemaker extractors on my old VH 308 (factory 308 heads). i'm pretty sure they bolt up the same to the injected 304 heads. i don't know if VB-VL extractors are different to VN-VS in terms of fitting in the car, but i doubt they'd be different. you might have to double check that with someone who knows for sure.

~ edit ~ lol, i was wrong on both counts. 308 carb & 304 injected heads are different for extractors... read posts below.

in terms of performance, on a stock motor it probably wouldnt make a huge difference. perhaps just noticable.

 

[383 hatch]

No, injected heads need different extractors to HQ (carby) style heads due to the port layout. For injected heads in a VK, you will need specific "conversion headers" as the VN extractors won't fit around the VK steering rack. You can buy them off the shelf from Pacemaker.

Depends on what is done to the engine, for a stock injected 5 litre, i think your better off sticking with the stock VN tubular style headers. IMO, i reckon they work better on a stocker.

 

[dirt drifter]

yes they make a difference, probably not the greatest difference though, my old vrss made 20rwhp more with pacie's and hi flow cats (it already had a cat back system)
pacemaker, and i'm sure other brands. make extractors to suit efi heads (symmetrical ports) into early commodores. the stock heads of that vintage were a siamese port so u need the proper extractors. dunno if stock vn-vs headers fit a first gen, anyone tried?
edit: blown V6 hatch beat me to it

 

[ari666]

without a cam there isnt much point. but yeah, as mentioned, pacemakers are the only one i have found so far with direct bolt on headers. 750 is the cheapest i got so far

 

[greenfoam]

On a stock 304 you will go backwards with pacemakers compared to the VN/HSV tube headers (came stock on all VN's and all the VN-VS HSV's), with a cam with a fair bit of overlap then you will be better off with pacemakers

 

[DANNY8]

without a cam there isnt much point. but yeah, as mentioned, pacemakers are the only one i have found so far with direct bolt on headers. 750 is the cheapest i got so far

There's a company on ebay that sell them for about $600 posted to ya door. And they fit with manual and power steering racks, not just power steering like the pacies.

 

[ari666]

link pls

 

[DANNY8]

Just checked again and they're $580 plus postage. He quoted me $38 for postage (rural SA).

HEADERS EXTRACTORS 5L EFI V8 TO VB VC VH VK COMMODORE - eBay Extractors, Exhausts, Car Parts, Accessories, Cars, Bikes, Boats. (end time 12-Mar-10 21:55:34 AEDST)

 

[v8commy]

im gonna run a crane 286,anti pump lifters,bosch 910 pump, blue tops, pod filter, motorvator y piece,catback sytem aww and a 25thou head shave