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Andrew Davies

crossflow street/strip build

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ok guys im about to start planning my engine for my daily but first uasage : will only drive 10 mins to work with no freeway usage so low gears will be on the list.
car is a 86 xf wagon that i have started doing mods on in prep for the new engine so far i have converted to single rail with a sports tuff exedy clutch, removed hub fan and converted to twin 12 inch thermos, installed pacemaker extractors with 100 cell high flow cat (to keep legalish) single 2.5 inch pipe and single straight through muffler.
i have built a few clevo's, windsors and 355's but i love the xflow and this is my 7th xf and i just enjoy driving it.
i build harley motors for a side gig also.
im not shy about running large cams.
so a few questions for those guys on here that have built these motors that might sway my direction on my build:
for my suggested combo would you stretch the budget for spool rods/ross piston ? i would rather hyper pistons so it wouldnt take as long to warm up and make clearances right  but thats up for debate.
should i modify my own sump to add volume (sheety by trade so mods wont be hard) if not what sumps are available ?
has anyone used crows steel rockers CRFX177 ? i have always used yella terra but these are cheap and crow recomends them for all of their listed cams hyd and solid.

so my plan is open for discussion and suggestions.
 

either hyper pistons and arp rod bolts or spool rods/ross pistons

comp i want around 11-1 but will have to cc the head after i port it to see what i can make it close to.
mls head gasket
arp studs for head and bottom end

already have a cain 4bbl manifold (looks new)
i have a 4bbl 600dp carb being built with 4 corner air bleeds and drop leg boosters
cam im aiming for around 250ish@0.50 
head porting i will do myself ( blending valve seats and radiusing short turn polishing exhaust ports only and port matching) nothing extreme.
ignition i have a est dist atm but looking at going tfi/msd6al 
has anyone used this rocker cover  ? http://kustombitz.mobile034.com/p/460373/ford-crossflow-41-finned-tall-alloy-valve-cover---polished-fins-and-sides.html
cam choice will be based on where my static comp lands so if it ends up higher than i want i will bleed a touch off with tightening the lsa.

some cams comp examples
11-1 250 single pattern 110lsa 560int 580exh lift
11.5-1 255int 260 exh 106lsa 580-600 lift
or should i just go with crow 14806 ?
these will depend on flow results after porting
diff will get upgraded after engine, lsd or tru track with 3.7's

any input appreciated

yes a barra would be cheaper and make more power but i have been there and like a challenge. 

if i can make 250rwhp i would be happy.

 

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I have never built a Crossy but I've learnt lots from here.

The old regulars who are experts rarely chime in nowadays so we're left with us to carry the torch.

They're just engines, so if you've screwed a few together before, you'll have no dramas building a reasonably stout street combo. Making one go like a V8 takes a lot more time, money and expertise than it would to just build a V8. It's something you'd do if you just really love crossys.

I would treat the rods as if they were stock Windsors. A set of ARPs should have it hang together fine up to 6k, but past that and the crank harmonics start playing havoc with the bottom end and cam timing. You'll start to need a massive balancer, good crank/rod balancing, maybe use an EF-EL crank (counterweighted).

Building past one horse per cube on these starts to become expensive. Using the yardstick of V8 builds that go one horse per cube, you'll need quite a lot more camshaft than they do (due to small ports/valves, big cylinders) requiring a stout top end.

Revving beyond that needs good breathing, and it's hard to fit bigger valves in a bore that small without compromises. The ports are pretty well-shaped, with generally smooth transitions and decent castings. They're not horrible like a standard 2V clevo, so it's harder to get the same gains. For instance, my clevo 2Vs only have about 3 hours of port work in them, but I reckon that's easily gained them 10%, just by smoothing the bowl and short turn, and tapering the guide boss. On a Crossy, you might spend 3 times that amount to get the same increase, because the ports are better to start with. The small valve size is the biggest hurdle. I think the actual problem is that they will end up touching each other if too big. Also, special machining of the seat inserts is needed so one will clear the other.

You need specific knowledge of these ports to get the best out of them without going backwards. This knowledge is so specific, that the gurus generally keep their work a secret, as it's their speciality business (speedway, etc).

The alloy head can take some compression, but I wouldn't go too silly. Aim for a dynamic comp of around 8.5 (online calculators are available) but that requires selecting a cam to suit.

Which brings me to camshaft. I always say... Start with the cam and build the engine around it. 250 at 0.050 on a 108 LSA is pretty damn wild, that would be a real handful of an engine with those cam specs. I mean... Full race spec. I would expect static comp to need more than 11:1 with that much cam. I wouldn't be surprised if you would rather need something around the 230 @ 0.050" on a 110 LSA. This of course needs beefier springs (mandatory anyway) and retainers, pushrods are a funny length (something like Buick V8 fits) so upgrading them could be a bit of a task. Clevo roller rockers are a bolt-on, so no trouble there if you want to source some other than the ones you mentioned.

Being a wagon... I know they're pretty heavy (I have an XE) so you'll want torque to get it moving. I would focus on filling out the torque curve rather than aiming for absolute top-end. Play to the engine's strengths I reckon.

Your induction side seems pretty sorted. 600 will get you the power you need, maybe even a little bit on the large side, but ok down leg boosters will help at lower rpm. General rule is target HP x 2 equals CFM needed.

I honestly don't think you'll get to 250rwhp without cubic amounts of money thrown at it. I think 200 is a more realistic figure and even that has to be a pretty healthy street engine. Keep in mind, they had half that standard.

250rwhp is way beyond even NA Barra territory, and they have heads that flow nearly double what a stock crossy can.

Sorry I don't have any proven "X list of parts equals Y amount of horsepower" formula, just a general approach from what I've learnt myself over the years and from others on here who actually do tinker with these things.

You seem to be on top of most of it, but I think the hp figure you quoted will be hard to reach without speciality parts and know-how

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considered boost? they respond very well to boost. 


the head i had worked on a fairly stock otherwise engine(flat tops, compression 11:1, cam way way too small LPGgas cam with higher lift mainly) was CNC ported from something they'd proven worked well (for them) had bigger intake valves only, and pocket ported mainly, intake runners were big enough to keep air speed was My understanding. 
 

 

 

 

for a WILD NA with a fair amount of info shared i'd always suggest a read of slydogs thread.. he's gradually changed over the years and it's now turbo and rarely gets updated lately

the other person i'd suggest reading about is Ando76  on NA builds

 

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Re: sump mods... normally, you can never have too much oil, so I'd say go for it... But if you're only doing short trips, the oil will always be cold, and even more oil will stay cold for longer. So I wouldn't bother modding the sump unless you knew that the oil capacity and temperature would be an issue.

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Gerg has already posted a good guide. & yes they get can expensive once your looking at over 250hp flywheel, they are only 140hp stock with carb,

Crow roller rockers will need 7/16" studs & guide plates, I'd go with Yella terra. I run the flat top polished version of Aussiespeed rocker cover, brought from Ron/Kustom bitz as well.

Key to power on Crossflow is head work, there is also a thread on xflow head porting in the Crossflow section, standard flow around 175cfm@.550", ported street head tend to be around the 205-215CFM@.550" quite a few ported heads tend to flow upto .550" then become harder to get higher lift flow. my CNC head flowed 236cfm at .550" & upto 250cfm @.650". A lower flowing head will need more camshaft duration to make similar power. Auto would be nicer for the strip,

 

My XF ute made 252rwhp rebuilt myself, balanced, 250 crossflow with hypertec pistons, resized rods with ARP bolts, C2 CNC ported head, 237@50 550" hyd cam, street terra rockers, crow moly pushrods, aussiespeed 4 barrel, QFT600 Vac sec, stock BW51 & regraphed XE/XF dissy (for now), 3.45LSD, figures say 10.1:1 Comp, still yet to race it after being tuned.

build thread below

 

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ford_man thanks for sharing your combo !
i thought i would need more comp and cam to reach 250 rwhp
yes the crow rockers need guide plates and machining for studs but the yella terra rocker to suite solid cams need this too (street terra are bolt ons that suite hyd cams but over twice the price of the crow units).
may i ask what brand piston you used ? i would rather use a hyp piston over forgies to keep cost down and it will be daily driven.
so i might be on track with more comp/cam to making 250rwhp also easier with a manual.
yes an auto would be nicer to drive but i like the manual.
i dont want boost on this car as i dont want to do engineers otherewise i would barra it.
thanks for the feedback guys muchly appreciated !

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I got scorpion rockers and some stepped studs and guideplates from summit. Was far cheaper than the yella terra option, freight out of the states was on par with out of oz too (New Zealander).

Since you have swapped to a rail, i recommend ironforce flywheels. Billet and half the weight, literally, of the xf flywheel. Swap your ringgear on and go. I had to drill out the mounting boltholes as i have the older block/crank. Ymmv.

And they look great.931e22ec99714126dbb7d399d003d295.jpg

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Pistons are Hypertec 20.5cc dish 3.7"/0.020" https://www.precisionintl.com/v/ford-australia-falcon-xf-4-1-1986-1993-petrol-ute/c/100000-standard/107000-rotating-assembly-components/107101-pistons Have also seen Silv-o-lite 3328H which is similar specs to ACL's crossflow 9411 8CC dish piston,

Yes was aiming for 10.8-11:1ish comp but head was measured at 49cc, I dare say the flow from the head helps to make up for it, or head CC is off?? but does have dished face EVL valves.

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a bit of an update

my spool rods and ross forgies have turned up.
have sourced another engine with a spare 4 speed cheap and stripped it down.

engine was out of an xe but it has a rubber crank seal and an unmarked hf4 head with a 52cc chamber.
bore is standard size, not that it matters because it will be going 40 thou over to suite the pistons.

i have started porting the head so far : gasket matched intake and exhaust, blended valve seats, stream lined around the valve guide.
still have to polish up the exhaust ports and unshroud the valves in the chamber.
unsure what it will flow but should make a bit of difference.
head will have new valve guides installed and a 3 angle valve job and a skim.
i will need to talk to my machine shop to find out what m.l.s head gaskets are available so i can work out comp ratio.
block will be decked to 0.
still undecided on cam atm if budget allows i would like a solid roller not so i can go bigger on cam but for not having to run in the cam and swap springs out.

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sorry for the late update, machine shop only just returned my stuff.
so they decked block to 0 then realised comp was 12.8-1 so they machined a small dish in my pistons and went with a 60thou mls head gasket.
crow sent wrong cam, i ordered the 14806 and got the 14626 still have to work out my final comp with this stick to see if it will work or ping its ass off.
machine shop forgot welsh plugs and fuel pump block plate (maybe more havent had a good look).
still waiting for my engine paint to show up (hopefully this week so i can start assembly on the weekend).
also crow didnt send a dizzy gear so that leads me to my next question : 
im currently running an est dizzy and im not sure if it will fit my new block (im sure its an xe block) ? 
not a big issue as i still have to order pushrods after i assemble and measure.
slow progress is still progress !
to make things worse my old engine is now hammering oil and coolant from the head gasket so i better get a move on !

xblock.jpg

xhead.jpg

xparts.jpg

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engine mostly assembled.
had to cut up some clevo guide plates and run them individually.
sent pushrods back to get some stock length ones because they are a perfect fit (we knew it would be hard to guess after all the changes).
left to do :
install a new bush and cam gear onto dizzy

waiting on pushrods so i can finish top end assembly
install oil filter

install water pump

install rear welsh plugs

install ballancer

install electric fuel pump and wire into car
then when i get a free weekend swap her in !

sorry for the slow progress (had a few issues with machine shop).

psstoons.jpg

stud.jpg

guide.jpg

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On 9/28/2021 at 6:45 PM, Andrew Davies said:

also crow didnt send a dizzy gear so that leads me to my next question : 
im currently running an est dizzy and im not sure if it will fit my new block (im sure its an xe block) ? 

missed this post, 

@Andrew Davies if it's an XD ALLOY  head block or later it will fit the EST or TFI or XE electronic dizzy no problem, (only the iron head has the big shaft points dizzy)

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engine has been in and out 3 times, chasing low oil pressure issue.
originally had a melling oil pump that dropped pressure 15 mins into bedding in the cam so swapped it out for a j.p pump.
now oil light comes on at idle but goes out at around 1k rpm.
going to put a guage on and see what its doing.
does anyone know what pressure the light comes on at ?
this thing is doing my bloody head in !
both pumps are std volume.
open for any suggestions !

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engine has been in and out 3 times, chasing low oil pressure issue.
originally had a melling oil pump that dropped pressure 15 mins into bedding in the cam so swapped it out for a j.p pump.
now oil light comes on at idle but goes out at around 1k rpm.
going to put a guage on and see what its doing.
does anyone know what pressure the light comes on at ?
this thing is doing my bloody head in !
both pumps are std volume.
open for any suggestions !
The idiot light is normally set at around 5 psi, so if it comes on when you're into it, it's already too late. At idle is less damaging but still not good. Something tells me that 2 out of 2 "bad" oil pumps isn't an oil pump issue at all. I think there's something wrong elsewhere in the engine.

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