Turbo US200 Crossflow

pmuller9":1n6kykhf said:
Which roller rockers fit the head after the stud conversion. BBC?
It is noted in several places on the AUS forums that the Cleveland 1.73:1 roller rockers fit the crossflow head.
I also read where mike1157 had to switch to a 1.75:1 due to valvetrain geometry issues. I think those are a BBC application. I assume his issue arose from some tolerance stacking complication possibly due to the grind on his Tighe cam or the roller lifter conversion, or both.
 
I am not aware of a direct comparison, but there are some CI head flow numbers in the tech articles and this thread has a handful of numbers on the crossflow
 
Post #7077 gives all the Fordsix. com references the former board user XRGlens cfm numbers from stock to fully modified in page 354 of Mike1157 build-up


The Classic inlines and Vintage inlines head has larger ports, and more aiflow with less valve lift. They are neck and neck everywhere because Mike W benchmarked the Crossflow head. Even the 2V iron head out flowed the crossflow intake.

145 cfm at 435 thou lift stock for the HF-1 head, to 275 cfm high ported and welded at 600 thou lift.

https://www.stangnet.com/mustang-forums ... 79&slide=0
 
I am going to let my engine parts picking inexperience hang out and hope that one of you will take me by the hand and 'splain things to me like a toddler.
I got a second cam recommendation, this one from Camtech. I can see that this cam is a single pattern with more duration and lift. What I can't wrap my head around is translating these numbers into real world performance.

20190605080216-3c3b0e6d-sm.jpg


I need to go back thru mike1157's thread and see if I can dig up the specs on his cam for comparison. There is plenty of subjective documentation of how that combo performed for me to digest
 
Kelford Camtech is my supplier from 1993, ex Christchurch, South Island shareholdership.

Its a Danger Will Robertson Cam. Checking durations off the ramp can be 6 thou, or 10 thou for earky SB Chevies. 20 thou is used by some companies. 50 lift has become industry standard.

David Vizard gave exceptionall clues to cams, camminess, and turbo synchronisation in his Ford S.O.H.C Performance book in 1988. Let he who has wisdom understand....pmuller9 s cam calcs are just like Vizards Isky 134 example.

He discussed lobe centers, off boost and C4 automatic torque holes off idle and how to fix them with reducing duration when both intake and exhausts are open 30 thou.

Google SCRID xctasy Ford S.O.H.C, and you'll get my three posts.

Re-read the EAO/Pinto stuff. What works on those worjs better on Ford Sixes.

The "at lash" duration is calculated below using the standard calculations pmuller9 has posted(see below).

The cam is a lot more intense off the seat than Mikes; CMA's is down around the 235 mark for 50 thou duration. A 250 engine has a 25% stroke increase that dulls that savageness, but 253 at 50 is exceptionally savage, and a turbo 200 wont work at all well with it off boost.

Its very similar aside.

Im touch screening this, so cannot re-edit wrongly pushed "fat fingered fone fugg ups" without constant re-edits, so any words miss-spelt, im truley sorry.

I use Thou as a short hand slang term, and the System Internationale 0.552 when I see .552. I blurt out 30 thou over when I see a .030 over 351C.

Sign conventions like net and gross valve lift are like negative and postive wheel offset. They vary from place to place. My conventions might not be the same as proper US convention

The first readings are at lash durations, intake and exhaust. The second, at 50 thou (.050) durations intake then exhaust, the third brace of numbers, the average lobe center angle, the average of two, intake and exhaust. The forth set, the with 1.73:1 rocket ratio gross lift, minus the lash setting.

The grind is just like Mike1157's.

The total duration is a little less than the part race solid lifter cams from the early 1970's used in 265 Hemi Six Pack Chrysler Valiant Charger E49's, and the Phase II and Phase III GTHO 351C 4v Falcon four doors. The intensity, second figure, is far, far higher, so it reakky has a much more savage load stress curve, making it very noisy, with more noise than Mopar or Ford would ever except. At more than 220 degrees at 50 "thou", the engine will be unsympathetic to vacuum advance, low stall converters, a/c compressor cut in, and powersteering or 130 amp alterntor or electric fan cut in, so electronic or manual idle kick-in "throttle kicking" and "ignition ramp tip in" stratergies might be needed to tame ragardness from engine catch at 650 to create a stable 900+/- 50 rpm idle. The LCA average governs how the engines cam duration melds in with the cylinder size. Turbo engines with big cames should have 4 degrees more LCA than a cammed up carb engine. Most modern EFi engines start with 5 degrees more LCA from the factory to favor emissions and tame liw speed ragardness. 113 indicates its designed for an EFi engine, but LCA is not a band aid, its a mandatory requirement to manage reversion in the intake charge. In my opinion, its purpose is to allow pulse tuning.

On small 200 and 250 engines, Ford used the same 109 degree lobe center as the bigger 302C and 351C engines, and then just retarded the cam chain sprocket or crank sprocket for emissions compliance. In the 1985 speed density EFi era, Ford Europe and USA added LCA, and removed built in cam retard. In Australia, everything was VAM Meter EFi till the OHC in line, but the bottom end cars were CFi speed density, and Multipoint EFi still used the tighter lobe center.

Early in, FoMoCo had limited cam master profiles, cam changes were costly, and Fords late sixties Cobra Jet and Super Cobra Jet split duration cams were designed to save Ford money in reconguring the exhaust systems on emissions vehicles with thermactors. For LeMans, example is the GT40 289 and 427 LeMans Total Performance cams the intake exhaust duration was split with 18 less duration on exhaust; overscavening was provided by a special bunch in bananas exhaust.

Different philosphies to the days when cam grind cost was immense, now, its a growth industry which allows American cam grinders to rule the world with. Just remember, it was Clay Smith and heavy fuels and Hillbourne injection that got things moving. Everyone else then the world over copies USA cam grinders.

For gross lift at the valve, the normal max of the intake valve times (x) the curtain area are calculated using a factir of 0.30. If your lobe lift is 0.325, your solid lifter lash 6 thou (0.006) becomes lost motion and thats just 0.319 at the lobe and your rocker ratio might be measured as 1.75 instead of 1.73:1 advertised, then your lift at the valve is .319 x 1.75, or .558 at the valve. With a later larger intake valve of 1.84, your active .30 curtain area is bang on .552. Any lift over that isnt wasted lift, but you need to know that huge 2nd, 3rd and 4th factors need to be managed.

Very importantly, Ford Australia used 15 cc dishes in the little 200 cross flows instead of 5.5 cc pistons in the US 200 and 250. Peak lift at the valve was just 0.435, and any 200 with a 0.558 intake lift might get close to needing more than 8.5 cc of piston relief. The angles of the Aussie X flow valves are different and flatter than the Boss 302 and Cleveland 351 heads, but Be Carefull. The Boss 302 engines needed relief cuts with the 505 cams to avoid piston to valve contact in 8000 rpm situations.

The 250 cross flow used 21.9 to 27.9 cc piston dishes. The US 250 added another 18 cc by a 0.103 or greater piston shortfall.
 
That is a lot of info to process, thank you.
xctasy":3jyl13gg said:
The grind is just like Mike1157's.
Do you have his specs handy? I was able to find where he listed the lift(.529/.559) but have not found duration or LCA numbers yet.

Regarding pmuller, he pretty much called out the first cam before I even emailed any vendors for recommendations! I am curious how the two recommended cams differ in performance/drivability.

I am used to driving a 2.3T with a cam and larger turbo. 950rpm idle, 7500rpm red line, full boost(22psi) at 3400rpm, cruises easily at 25-3000rpm. 93oct fuel.

I am not looking for a 600rpm idle, and 1700rpm cruise. I will be running a manual trans and am not afraid to drop two gears from cruising speed to put a gap on somebody. I will have EFI, e-fans, and A/C. I do expect drivability similar to my 2.3, and the ability to stay on 93oct fuel, with much more power!
 
Search Mike1157's early posts here. Members mike1157, select anyone of his 181 posts. He asked me for a best choice roller cam spec after I gave him Psycho250's roller cam conversion data.



viewtopic.php?f=1&t=70927&start=50


Dean Tigue sent him three specs. I told him to get the widest lobe center angle.

A Bensons Turbo guy gave me advice on cam selection for 202 Holdens via a 1987 Australian Street Machine article. You just have to avoid overscavenging.
 
Will do. Probably easier than sifting thru the stangnet thread again, thanks.

Isn't it like 3am where you are? Don't you sleep?? :)
 
I've spent years asking for info, often with very little sucess, and many sarcastic responses from a lot of normally very great people. Since I do night shift construction professional services work for government projects, I don't mind helping out.

The worst thing is missinfo, the new antidote to free info sharing.


The cam specs are hard to find as Mike 1157 moved on when he found the FSP forum hard going and not performance orientated.

As I had a Fox Mustang 3.3, I retreated to Four Eyed Pride after many issues and a lot a hassle posting pictures here at Fordsix.com

Mike1157 lost acess to extra picture posting, and got out of FEP eventually.

I now remember that the cam specs are elseware; I've only copied them here in the past.

Once I get back to my desktop, I'll update the links below.

The Stangnet reference is:-

The page before this one...

https://www.stangnet.com/mustang-forums ... 3/page-376

The Four Eyed Pride reference is:-

Post#77
http://vb.foureyedpride.com/showthread. ... la-Monster)/page4

The Ford Six Performance ref is:-

Post#6

viewtopic.php?f=22&t=76080&p=585795#p585795
 
The 253/253 single pattern cam from Cam-tech has two shortcomings.
First it has way too much duration for the rpm range and power band you want the engine to run at.
Second if a log type manifold is being used rather than a long tube header, a profile with less exhaust duration will run with higher efficiency.
There are two parts to the exhaust cycle.
The first part is the blow-down where the exhaust valve opens and the high pressure enters the exhaust system and continues until the cylinder pressure equalizes some time after BDC.
This is where the turbocharger picks up the exhaust energy that would have been wasted.

Next is where the piston pushes out the remaining exhaust and whatever pressure remains against the piston is a pumping loss and any pressure in the cylinder at the time the intake valve opens can delay the beginning of the intake cycle along with intake port reversion at low rpm.

The times I have data logged the exhaust pressure of a long tube turbocharger exhaust system showed scavenging enough to bring exhaust pressure at the port down to zero.
A single pattern cam profile works under this condition.

A log style manifold doesn’t offer a high level of scavenging and in some cases non at all so it is better to reduce valve overlap and exhaust duration and increase the LSA to focus more on the blow-down portion of the exhaust cycle.

A profile with an .050” intake duration in the low to mid 240s will make good power between 7000 and 7500 rpm.
An exhaust duration with 8 to 10 degrees less duration than the intake with a 114 degree LSA will be more compatible with a log style exhaust manifold.
 
pmuller9":2gglsz5s said:
A profile with an .050” intake duration in the low to mid 240s will make good power between 7000 and 7500 rpm.
An exhaust duration with 8 to 10 degrees less duration than the intake with a 114 degree LSA will be more compatible with a log style exhaust manifold.
I read, "Get the Crow cam and stop fussin!" I don't doubt your experience here, but that guy hasn't answered my email since he told me the crossflow head won't go on my block. :nono: I asked about why the card specs a hyd lifter on a mechanical cam and what other spring options he has, but have gotten no response.

I am still exploring and learning. I will try to make up with Martin at Crow once I have satisfied all my curiosities. :unsure:
 
Don't worry about getting springs from the cam supplier.
You can get springs elsewhere.
Comp Cams has a conical spring that will work very well for your application.
Comp 7228, 136@1.800" with a 438 lbs/in spring rate.

What will the valve stem diameter be?
 
I was mostly only curious as I found the wrong lifter called out and thought maybe the listed spring was incorrect as well. I have given my cyl head guy free run to choose the valves/springs/retainers that will go in the head. He mentioned possibly dropping stem diameter, and beehive or conical springs as well. We have not talked further about that yet. That Comp spring does look nice 8)

With Crow gone incommunicado, Camtech being considerably cheaper, and having built a bit of conversation with Malcolm @ Camtech, I decided to try and reign in his choice based on info in this thread. I received this just a few minutes ago:
20190606222950-1d45ffc4-cu_s9999x200.png
 
As previously mentioned the turbo is big for a 200 cu in engine but you can run the 246/246 cam and push the rpm to keep the turbo happy.
The idle will need to be high around 1200 rpm.
For street use I would prefer to see 246/238 on a 114 LSA.
It would be much easier to tune and improve low end response as mentioned.
Hoping the ported head can show .600" intake flow numbers near 230 cfm.
 
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