Having just got the busted (fuel pump) bolt out of the block of the xflow and got it up and running again I was thinking about carby setups. I'm getting a new manifold and a Holley in a couple of months (probably a 465). What I was wondering about was has anyone done a twin weber setup for a XFLOW?
I know there are a few tripple webber jobs, but they are 45mm sidedraught jobs, what about a twin 34ADM setup?
Given they go alright with a sorted weber, they should absolutely hammer with two of them. I'm assuming no one manufactures anything like this. What would you be looking at for someone to make one up or a pair of 3 cylinder manifolds each with their own weber?
This might be a bloody stupid idea, then again if you could set it up properly it'd be a monster.
465's work pretty well. Redline's been making manifolds for them for years. Vacuum secondaries and small primaries (about 180cfm I think) mean they're pretty good on a big six - as good or better everyday fuel economy and more power when you need it than a 350 Holley. There's a few 250's out there running Holley 500's, but I reckon that's asking for trouble - too big and only 2 very big barrells.
As long as you're not flogging the arse off it all day everyday it shouldn't be a problem.
Damn that's some juice. With the jetted weber I get about 14L/100km when I go easy and about 20-22L/100km when I'm not so gentle. I just got a 450 Holley w/mechanical secondaries & I'm getting the redline manifold in a week or so. How hard was it to setup?
At the moment the setup is 250 with a reco ULP head, Perry extractors, 2 1/2" exhaust, redline 9" assembly & air filter. U reckon a 450's overkill eh? The attraction of a 4 barrell was the better secondary setup and lower consumption when on primaries. The bloke who had it before reckoned it was cammed, but I don't know he was full of **** about one or two things. All the same she should absolutely hammer with the new setup and if the carby's too big, I'll just have to get a bigger cam.
I'd love to setup the twin weber system though. I'll look at it down the track if I can find somone who can fabricate a manifold. Probably be easier to get an adaptor made up to fit to a Redline 4 barrell manifold...
Cheers for the feedback. I could do with some advice setting the 450 up as I haven't fitted a Holley before and don't have too much experience with them.
Mid 15's aint bad for a NA XFLOW, so thats making about 50kw over stock.
One of the (few) local mechanics who hot fords up reckons he can get 180rwhp out of a 250 with just cam, lifters extractors, exhaust, 450 Holley & manifold. That'd be about 180kw. You reckon they might be exagerating?
Other thing they mentioned was stroking the 250 using 221 rods?? ever heard of that? I know the 221 head's an absolute killer on a pre-XFLOW, but I would've thought you'd be asking for trouble stroking a 250 any further.
i reckon the twin weber with custom manifold/s is an excellent idea. i dont reckon the manifolds would be too hard to make for someone who can weld aluminium. i suppose the easiest way i can think of is chopping up a few manifolds and mating them together - cheap as chips from wreckers or classifieds. joining the two carbies together wouldnt be too hard either. u'd only have to modify one of the throttle shafts to accomodate a linkage between the two. great idea - i love it. if you do decide to do it, let me know how u go
Mid 15's aint bad for a NA XFLOW, so thats making about 50kw over stock.
One of the (few) local mechanics who hot fords up reckons he can get 180rwhp out of a 250 with just cam, lifters extractors, exhaust, 450 Holley & manifold. That'd be about 180kw. You reckon they might be exagerating?
Other thing they mentioned was stroking the 250 using 221 rods?? ever heard of that? I know the 221 head's an absolute killer on a pre-XFLOW, but I would've thought you'd be asking for trouble stroking a 250 any further.
I'd say they might be spanking it. My engine has been completely rebuilt with a shaved and ported head with oversize valves, redline 4 bbl and 465 holley, genie extractors, lumpy cam (.495lift int+exh 214 duration @ .050) and a custom cold air intake and it makes 150rwhp (116rwkw). I would love to see any straight 6 making more than that because the cam would have to be wild to get 180rwhp... almost undriveable on the street.
Destroking to a 3.3 crank and rods is popular in turbo applications and using the 221 bottom end and the non crossflow 2v head is a wicked combo when being used for racing, but again they are not thet good on the street becaue of the extreme cam that has to be used.
The 450 should be an easy fit. You shouldn't need to change anything except the kickdown cable bracket if its an auto. My bracket was custom made by the local tranny shop when the new auto was installed. I mistyped in my previous post... a 390 holley 4 bbl would be a good choice for a mild cam/extractors but do not bother installing bigger intake/exhaust manifolds unless you put in a bigger cam. The stock crossflow cams are absolutely pathetic and you won't get anywhere near the best out of your engine unless an aftermarket cam is installed.
Cheers guys. I've put a deposit down on the manifold - cost $260!!!!! And that was cheapest in town by $40. They're getting it shipped over late this month. Can't wait. Will the accelerator cable be alright or do I want something like a v8 cable off a XD or an XE?
I'd still rather do the twin webers, but I'd *#@$ it up for sure.
I'll be able to fit the EFI rocker cover I got and setup for the 250 the other day - had the old one off and was fitting the EFI cover when I found out that the throttle nudger on the webersticks out about 3mm too far - end result? Lot's of swearing and cleaning blue sealant off the head & cover and putting the old one back on. The EFI cover looks so much better than the carby job.
Do you reckon it's worth going to a dyno or just to a carby joint to get the Holley tuned to the 250?
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