Thread: 4.6 into '81 two door

Thanks, I knew about the Holley's, but what would be the best single carb to use ?

Roger

Not really sure, I'd stick to the twin side drafts myself. I'm sure someone will be able to assist there though - there's bound to be something.

Not sure if anyone is still mucking around with the Quadrajet? They used to be readily tunable to different engine sizes and power outputs.

Edelbrock do some, and their design is different to the Holley and the Holley clones so it may be ok as far as fuel starvation goes, but I'm not talking from any experience at all.

EDIT - just done some googling, the Quadrajet is still alive and well it would seem and is readily available in Australia both second hand and reconditioned - although some of the prices of the recoed ones will make your eyes water...

how much is throttle body injection these days ...

These guys fit it and get it working on the side of the road in the snow ... and she fires up and runs first try

https://youtu.be/3EkWEjTBZ9Y?list=PL12C0C916CECEA3BC

That way you avoid the offroad issues of carbies and will have a heap more power than using the old twin side drafts.

seeya
Shane L.

.....I would really like to get away from the old sidedrafts, mine are about had it.This vehicle originally came from Mt Isa, so its had a bit of a hard life, but surprisingly low mileage, and now its down here in Tassie.Bit of a climate change !!

Roger

Originally Posted by DoubleChevron

how much is throttle body injection these days ...

These guys fit it and get it working on the side of the road in the snow ... and she fires up and runs first try

https://youtu.be/3EkWEjTBZ9Y?list=PL12C0C916CECEA3BC

That way you avoid the offroad issues of carbies and will have a heap more power than using the old twin side drafts.

seeya
Shane L.

I like that a lot!

Wonder what sort of price it runs to.... BRB...

EDIT - around $2.5K US. A little steep, but a nice setup and about the simplest way to install EFI I would think. On something that's worth a few dollars to start with, ok I would think but on an old Landy...

Some Americans have suggested the Holly injection system that replaces a holly carb but is very very expensive - but is install and forget as it learns runs about $2500 - $3000 depending on what you actually do.

There are new offroad inlet manifolds and carbs RPI in the UK suggest Edelbrock Weber 500 CFM conversion - expensive if I buy from the UK but cheaper locally - not sure about offroad use but is probably OK.

Americans also suggested the Holly Truck Avenger 670cfm carb but it is too big for a 4.6 but their 470CFM would suit better - locally sellers advise that it is an offroad carb and not suitable for onroad use or towing due to high fuel use.

Two 175CD carbs are on the limit for a 4.6 (my 5.3l Jag has 4) and revised jetting is not ideal but they do work and are well known and simple and reliable - so if you just want an engine to run OK with still high fuel consumption they are an alternative.

Oh back to injection - I mentioned a 4CUIX hotwire system of a 3.9 cheap and simple but different fuel pump needed - speaking to an acquaintance last night - he has a 5.1 RV8 in his 101 - get 16 l/100km now 101 owners will be really envious - he runs the 4CUIX on the 5.1 and still running the restrictive 101 manifolds so the 4CUIX on the 4.6 would be a cheap alternative for an early RR.



Garry

Originally Posted by yumastepside

.....I would really like to get away from the old sidedrafts, mine are about had it.This vehicle originally came from Mt Isa, so its had a bit of a hard life, but surprisingly low mileage, and now its down here in Tassie.Bit of a climate change !!

Roger

There's a bloke just near Essendon airport who reconditioned my Strombergs and did lovely job. His name is Tony at B & M Fuel Systems. I'm sure he would be able to rejet yours to run a 4.6. As long as you don't want to rev the engine too much.. Can't get enough air through too run the engine at high revs or so I was told. Would be quite torquey though.
You have to be careful of the CD175s with auto choke..apparently a PIA.
By the way I had a Quadrajet on a small block Chevy in a Rangy a long time ago . Didn't like it much because of the sudden jump in power when the extra jets opened up.

I've got the Edelbrock Performer 500 which is actually based on a Weber design. Yes I know its not yet running but all feedback from states (Mark at D&D fabrications -http://aluminumv8.com/) are that this carby is good off road.
Price from him jetted for your use was very reasonable I paid $325 US a few years ago. Manifold - again I brought an Edelbrock performer locally for less than price of carby. While not as good as Holley fuel injection not too bad for money spent.