VR V8 EFI in Opel Monza

[Gse]

Today i got some Ford 289-302 headers from the unfriendly postman

The fit 1:1 to the ports of the 304 only the header flange bolt pattern sucks,i take a grinder cut the welds loose and weld my own laser cut header flanges on the headers..
The fit even into the chassie rails of the engine bay,the clearance is very tight,but shut be enough for the engine to move a bit wenn u rev it up.

There is only one big thing i dont like,they are shaped that they end right above the steering rack,so i need to short it and weld me a tube with a 45% degree angle on them...

I,ll post pics here while u people are asleep lol

 

[VR38]

Good to hear some progress.

 

[dags061]

Cant wait to see photos of the finished car. I want to import one into Aus one day when i have a bit of money.I lived in switzerland 11 years and the first time i saw a Monza I almost crashed my car.Why didnt Holden make them as well as Commodores.

 

[Reinhoud]

Hmmm, useless post, so I deleted it...

 

[juiceie vh sle]

chuck some pics up of the modified headers im interested as to see how they look. never would of thought ford headers match up 1:1 . great build by the way really unique. must be frustrating being over seas though trying to order everything.

 

[Gse]

Well i laughed to hard....

My driver side/australian passenger side fits really good,i could use that header with hardly any changing,but the Australian driver side or my passenger side is rubbish,i have my starter there now,and the 4-1 collector is:

1:to big it doesnt fit between engine mount and startermotor
2:the header is way to long,it almost comes to the bottom of the K-frame
3:the header is to wide,it would hit the chassie rail..

So i took a diffent path now,i got me some 48mm outside and 43mm inside diameter 90degree bends that i will will weld to the header plates i have,and i will copie the stock cast iron VR headers in mirror vieuw,i will lead the driver side (aus passenger side) between trannie and block just as a stock VR has..I will use 2 inch pipe for the header as max..

But i have twin 1 3/4 pipes with one muffler each and no cats...Will that be enough or do i need a bigger exhaust,i am reading a lot about exhaust on 304/308:
Some use a single 2.5 inche pipe others use a 2.25ince to 2.5inche pipe others use twin 2.5 inch..some use twin 2.5 inch to 3 inch..and so on in aus u have combinations..

My 304 is 100% stock only has a Greenfoam tune and will runn on LPG most of the time with a impco 425 LPG mixer..I am not after big power or anything i just want the thing running well and perform nice,i know the bigger the better but,i have twin pipes hanging under the car,and i did the maths twin 1 3/4 pipes have the flow surface as single 2.5 inch pipe,i have just 2 mufflers in the middle of the car and thats it...So the flow in these 1 3/4 inche pipes is okay..

What u people think?

 

[Haydz]

good work i didn't know this was still going. about pipe sizes i reckon single 2.5 would be all you want for a stock engine. standard on a commodores is single 2.25.

 

[VR38]

I would be using twin 2" at minimum.
IMO 1 3/4 is too small to get any sort of decent muffler.

 

[vkberlina]

Twin 2.5" into a single 3"

 

[Gse]

My crank can move 0.15-0.2mm in and out the block in other terms i have endplay that i dont like,the engine did 308.000km and i have the feeling it had a rebuild,cause i find liqued gasket everywhere (intake manifold sump timing cover).
The engine ran well and had grunt enough according to Jason/Greenfoam who did the memcal tune and he drove plenty of 304,s and told me that the engine was performing well,it burned no oil and used no water...Shut i worrie abouth this or just bolt the trannie back on now?????

Cheers Ben