theoldwizard Posted December 20, 2009 Share Posted December 20, 2009 Any chance the 5.0 will improve highway mileage with cylinder de-activation strategies? Last I knew (2+ years ago), Ford has abandoned cylinder de-activation. Difficult to implement on OHC and problematic in conjunction with TIVCT. Quote Link to comment Share on other sites More sharing options...
Inselaffe Posted December 20, 2009 Share Posted December 20, 2009 (edited) I'm a bit nervous on this as I have heard there are a few people unhappy with the 3.5L due to lifter (okay, technically bucket) noise from excess clearance. I'm sure you'll deny this, but I've heard that the Coyote isn't DAMB but hydraulic lifter with roller finger follower with a similar setup to the previous Mod 4V, i.e. the HLA's on the inlet between the inlet port valve. Most basically I've heard it is not a Mod (castings are all different) but it still has Mod bore centres and almost Mod machining. I heard that was why Ford stayed away from DAMB valve gear for so long, is there any way of having an adjustable lash cap or bucket arrangement? Yes INA do them and the Germans have been using them for years, although strictly it becomes a DAHB. INA also have the cam-profile switchable hydraulic tappets (these are used by Porsche, Volvo and Jaguar). The power number from the "Coyote" is very impressive, but it is the torque number (if it has been reported correctly) that is nothing short of astonishing! 390lbft from a naturally aspirated 5.0 litre is about 13.3 Bar BMEP, which from a cross-plane V8 with it's inherent uneven firing per bank is extremely difficult to achieve. If I put this into context this beats BMW, Porsche, Audi, Maserati, Jaguar and only Toyota/Lexus beat this with a V8 and they are using DI. http://www.autoweek.com/article/20091218/DETROIT/912189996 From this article it says they are using TI-VCT I guess that it is the BorgWarner cam torque actuated system already used on the 3.0 V6 and by Jaguar on their V8. It also says that there are tuned exhaust manifolds, I would guess to achieve this torque they are using fabricated assymetric 270deg grouped exhaust manifolds (one bank groups cyls 1to3 & 2to4 and then the other bank groups 1to2 & 3to4). It would also have to have extremely low back pressure exhaust system (less than 250 mBar). A very low loss intake system, from the picture in the article the inlet pipes are enormous, the throttle is in a good position, the inlet runners have very good R/D ratio, and also it doesn't appear to have a MAF sensor. Without a MAF sensor they would have to use speed density and torque based mapping, which requires a lot of dyno work to ascertain a very detailed volumetric efficiency map. I do wonder if Dave Szczupak (before he left) had some influence in the targets for this engine. Perhaps a little credit could go to him. But not wishing to take too much away, I definitely doff my cap to the engineers in Dearborn for this one! Edited December 20, 2009 by Inselaffe Quote Link to comment Share on other sites More sharing options...
Edstock Posted December 20, 2009 Share Posted December 20, 2009 but it still has Mod bore centres No. They're wider. Quote Link to comment Share on other sites More sharing options...
Inselaffe Posted December 20, 2009 Share Posted December 20, 2009 No. They're wider. We shall find out soon enough! Quote Link to comment Share on other sites More sharing options...
theoldwizard Posted December 20, 2009 Share Posted December 20, 2009 (edited) I'm sure you'll deny this, but I've heard that the Coyote isn't DAMB but hydraulic lifter with roller finger follower with a similar setup to the previous Mod 4V, i.e. the HLA's on the inlet between the inlet port valve. Most basically I've heard it is not a Mod (castings are all different) but it still has Mod bore centres and almost Mod machining. You are correct, I'm telling you that some one is confusing the Ford Racing Five Oh Cammer (used in the FR500) with the Coyote. Coyote is definitely DAMB, with twin independent variable cam timing. Definitely different bore spacing than the modular (none of the cylinder bores are siamesed like the Five Oh Cammer). Edited December 20, 2009 by theoldwizard Quote Link to comment Share on other sites More sharing options...
White99GT Posted December 20, 2009 Share Posted December 20, 2009 Is the Coyote bore spacing known yet? Quote Link to comment Share on other sites More sharing options...
Swizco Posted December 21, 2009 Share Posted December 21, 2009 You are correct, I'm telling you that some one is confusing the Ford Racing Five Oh Cammer (used in the FR500) with the Coyote. Coyote is definitely DAMB, with twin independent variable cam timing. Definitely different bore spacing than the modular (none of the cylinder bores are siamesed like the Five Oh Cammer). This is a teachable moment: DAMB...? Cylinder bores 'siamesed'? Help us non-powertrain people with these terms, oh Engine-Guru! Quote Link to comment Share on other sites More sharing options...
jpd80 Posted December 21, 2009 Share Posted December 21, 2009 (edited) This is a teachable moment: DAMB...? Cylinder bores 'siamesed'? Help us non-powertrain people with these terms, oh Engine-Guru! DAMB: Direct acting mechanical Bucket. the buckets ride on the camshaft and operate the valves directly, unlike Roller Finger followers where the valves are actuated indirectly using a rocker or a finger. Siamesed cylinders is where there's no room for a water jacket between the cylinders, usually caused when the piston size is increased to gain maximum capacity out of the block. Edited December 21, 2009 by jpd80 Quote Link to comment Share on other sites More sharing options...
theoldwizard Posted December 21, 2009 Share Posted December 21, 2009 Swizco, the "bucket" is the thing just below the camshaft that sits on top of the valve, valve spring, valve keeper assembly. Yes, it is upside down. Footnote: Most DAMB engines use shims in the bucket to adjust for different valve to cam clearances. The 3.5/3.7L (and I'll bet the new 5.0L) actually use buckets with the top ground to different thicknesses. It might make assembly easier, but it will certainly make field adjustment more difficult (if required) as the mechanic will have to have an assortment of buckets. IIRC, there is no recommend interval for checking bucket to cam clearance on the 3.5/3.7L engine. Quote Link to comment Share on other sites More sharing options...
rkisler Posted December 21, 2009 Share Posted December 21, 2009 Swizco, the "bucket" is the thing just below the camshaft that sits on top of the valve, valve spring, valve keeper assembly. Yes, it is upside down. Footnote: Most DAMB engines use shims in the bucket to adjust for different valve to cam clearances. The 3.5/3.7L (and I'll bet the new 5.0L) actually use buckets with the top ground to different thicknesses. It might make assembly easier, but it will certainly make field adjustment more difficult (if required) as the mechanic will have to have an assortment of buckets. IIRC, there is no recommend interval for checking bucket to cam clearance on the 3.5/3.7L engine. Wizard (or jpd), a quick question. I have friends with various engines with direct actuating valves (for instance a Ducati and Honda Interceptor). The specs usually call for checking the clearance and shimming where necessary, and those checks on tolerances are usually every 6-12k or so. On the Ducati, it's been spot on each time over around 25k. So, I understand that motorcycles run at higher rpm's, but what enables Ford to build an engine that has "built for life" buckets that have no maintenance procedures and presumably (at least on paper) will always be within spec over the life of the engine? Is it materials technology? Or do the motorcycle manufacturers just want to give the shops some business? (The procedure on the V4 Interceptor takes about 8 hours as it requires removal of the 6 cams). Wizard, I'm sure you'll appreciate that the "ancient-by-comparison" rocker adjustment on my BMW RT only takes me a few minutes. Quote Link to comment Share on other sites More sharing options...
Swizco Posted December 21, 2009 Share Posted December 21, 2009 Swizco, the "bucket" is the thing just below the camshaft that sits on top of the valve, valve spring, valve keeper assembly. Yes, it is upside down. Footnote: Most DAMB engines use shims in the bucket to adjust for different valve to cam clearances. The 3.5/3.7L (and I'll bet the new 5.0L) actually use buckets with the top ground to different thicknesses. It might make assembly easier, but it will certainly make field adjustment more difficult (if required) as the mechanic will have to have an assortment of buckets. IIRC, there is no recommend interval for checking bucket to cam clearance on the 3.5/3.7L engine. Got it! I am familiar with the different valvetrain configurations, just not their definitions. I had shims in my old 1982 GS1100L street bike - I had them shimmed right on. I recall that with shims, you can adjust the valve clearances without pulling the cams. The Ford motors sound like valve adjustments will require a lot more work. Great stuff, guys! We need more tech-heavy content on this site (and in life). Quote Link to comment Share on other sites More sharing options...
Swizco Posted December 21, 2009 Share Posted December 21, 2009 Wizard (or jpd), a quick question. I have friends with various engines with direct actuating valves (for instance a Ducati and Honda Interceptor). The specs usually call for checking the clearance and shimming where necessary, and those checks on tolerances are usually every 6-12k or so. On the Ducati, it's been spot on each time over around 25k. So, I understand that motorcycles run at higher rpm's, but what enables Ford to build an engine that has "built for life" buckets that have no maintenance procedures and presumably (at least on paper) will always be within spec over the life of the engine? Is it materials technology? Or do the motorcycle manufacturers just want to give the shops some business? (The procedure on the V4 Interceptor takes about 8 hours as it requires removal of the 6 cams). Wizard, I'm sure you'll appreciate that the "ancient-by-comparison" rocker adjustment on my BMW RT only takes me a few minutes. I recall shimming my old 900SS required two shims per valve, due to the desmodromic configuration. What a pain in the a__: I wonder if that pic will work? Quote Link to comment Share on other sites More sharing options...
rkisler Posted December 21, 2009 Share Posted December 21, 2009 I recall shimming my old 900SS required two shims per valve, due to the desmodromic configuration. What a pain in the a__: I wonder if that pic will work? Yep, with a desmo, you have to adjust the up and the down.... Quote Link to comment Share on other sites More sharing options...
Project-Fairmont Posted December 21, 2009 Share Posted December 21, 2009 (edited) I hope not. I don't want my Mustang to sound like a Civic on the highway. Not a fan. I rented an SS with cylinder deactivation - it does not create a four cylinder sound, impossible really as an in-line four has crank pins on the same plane (flat) while a "4 cyl" V8 has cylinders firing using 90 degree crank pin phasing - sooo you still have a V8 growl as a result of exhaust imbalance. What you do get though is a strange vibration as the engine is put to sleep so-to-speak at a very low RPM. As I posted on BON (ford's competition forum), the 6.2 6A SS is a disjointed unresponsive drivetrain for sure. Also, a Ford took another Engine Masters competition - six of the top ten places were Fords including first place (388ci CHI head Cleveland)...runner up was a 435ci LS7. Ford motors have pretty much dominated the Engine Masters since its inception in 2002. http://www.cpgnation.com/forum/2009-engine...lenge-2864.html Edited December 21, 2009 by Project-Fairmont Quote Link to comment Share on other sites More sharing options...
MY93SHO Posted December 22, 2009 Share Posted December 22, 2009 Got it! I am familiar with the different valvetrain configurations, just not their definitions. I had shims in my old 1982 GS1100L street bike - I had them shimmed right on. I recall that with shims, you can adjust the valve clearances without pulling the cams. The Ford motors sound like valve adjustments will require a lot more work. Great stuff, guys! We need more tech-heavy content on this site (and in life). Kawasaki recommended checking the cam to bucket clearance every 5000 miles on my 1984 1100 LTD. After a while I got smart and checked mine during the winter. My clearances never changed for over 50,000 miles. My buddy bought a cheap Kawi 650 CSR that was a holdover. It was two years old but still in the crate. He treated that bike like a rented mule. Never checked the valves until it had 65,000 miles on it. Still within specs. I think the intervals are set by the lawyers to cover their asses. Quote Link to comment Share on other sites More sharing options...
Inselaffe Posted December 22, 2009 Share Posted December 22, 2009 (edited) Wizard (or jpd), a quick question. I have friends with various engines with direct actuating valves (for instance a Ducati and Honda Interceptor). The specs usually call for checking the clearance and shimming where necessary, and those checks on tolerances are usually every 6-12k or so. On the Ducati, it's been spot on each time over around 25k. So, I understand that motorcycles run at higher rpm's, but what enables Ford to build an engine that has "built for life" buckets that have no maintenance procedures and presumably (at least on paper) will always be within spec over the life of the engine? Is it materials technology? Or do the motorcycle manufacturers just want to give the shops some business? (The procedure on the V4 Interceptor takes about 8 hours as it requires removal of the 6 cams). Wizard, I'm sure you'll appreciate that the "ancient-by-comparison" rocker adjustment on my BMW RT only takes me a few minutes. I don't think these guys will be able to answer that, not many people can and I only know so much. What Ford have been able to do (with I guess a bit of help from Jaguar who have used this technique for decades) is achieve a "sweetspot" in balancing the cam-follower Hertzian contact stress, lubricant entrainment velocity and therefore oil film thickness by careful selection of the cam base circle size and design of the cam-follower acceleration profile for the typical operating range of passenger car engine. Material properties of the contact faces are obviously important but it is not necessarily about selecting the hardest most wear resistant material. It is about selecting material specifications that are consistently predictable and easy to control in the manufacturing process and designing the cam-follower behaviour to be within those limits. In the case of motorcycle engines the most important thing is power and this means opening the valves at much higher speeds. So controlling the valvetrain to not lose follower contact at high cam speeds further constrains the cam-profile design for acceptable contact stress and makes it is more difficult (if not impossible) to achieve that "sweetspot" with respect to lubricant entrainment velocity and therefore oil film thickness. Edited December 22, 2009 by Inselaffe Quote Link to comment Share on other sites More sharing options...
jpd80 Posted December 22, 2009 Share Posted December 22, 2009 (edited) DAMB has been around for a long time and Ford is fairly late to the party so of course others like European and Japanese car makers have already charted the course. I'm betting the after market will bring out cams and shim bucket adjustment kits for Ford's new engines. It's only natural for them to identify areas for improvement, pretty soon tune up shops will be ripping into Ecoboost V6 engines trying to extract 600 to 1200 hp - don't believe me , they do with the Falcon I-6...... Edited December 22, 2009 by jpd80 Quote Link to comment Share on other sites More sharing options...
rkisler Posted December 22, 2009 Share Posted December 22, 2009 I don't think these guys will be able to answer that, not many people can and I only know so much. What Ford have been able to do (with I guess a bit of help from Jaguar who have used this technique for decades) is achieve a "sweetspot" in balancing the cam-follower Hertzian contact stress, lubricant entrainment velocity and therefore oil film thickness by careful selection of the cam base circle size and design of the cam-follower acceleration profile for the typical operating range of passenger car engine. Material properties of the contact faces are obviously important but it is not necessarily about selecting the hardest most wear resistant material. It is about selecting material specifications that are consistently predictable and easy to control in the manufacturing process and designing the cam-follower behaviour to be within those limits. In the case of motorcycle engines the most important thing is power and this means opening the valves at much higher speeds. So controlling the valvetrain to not lose follower contact at high cam speeds further constrains the cam-profile design for acceptable contact stress and makes it is more difficult (if not impossible) to achieve that "sweetspot" with respect to lubricant entrainment velocity and therefore oil film thickness. Thanks a lot, Inselaffe! Yes, Jag does have a lot of experience. I think I'm correct in stating that Jaguar insisted that the V6 Duratec 3.0l go DAMB when it was turned NS for the D2 platform (LS/S-Type) as the base EW engine was RFF I think. The AJ V8 is DAMB. And the relatively new 3.5l Duratec is DAMB, so it makes sense for Ford to standardize head philosophy across the board. If done right, I would think there are some weight, cost, and efficiency gains vs. RFF, but I'm not well enough grounded to know. Your explantion sounds spot-on and is very helpful. Quote Link to comment Share on other sites More sharing options...
theoldwizard Posted December 22, 2009 Share Posted December 22, 2009 (edited) Yes, Jag does have a lot of experience. I think I'm correct in stating that Jaguar insisted that the V6 Duratec 3.0l go DAMB when it was turned NS for the D2 platform (LS/S-Type) as the base EW engine was RFF I think. To the best of my knowledge all Duratec 3.0L engine were/are RFF. The newer Duratec/EcoBoost 3.5/3.7L are DAMB. The Jag/Lincoln LS/Thunderbird V8 was the first DAMB in a Ford/Lincoln badged US vehicle. As far as "how do they get away with no recommend service", including not even checking clearance, I don't know. Lower RPM (compared to motorcycles engines), lower continuous power output (compared to 4 stroke outboards) helps a lot. I suspect better oil additives also helps a lot. Hardened valve seat (been around forever now) also helps. Better underhood/cabin noise insulation could also play a part if the customer never hears the buckets clicking against the cam ! Edited December 22, 2009 by theoldwizard Quote Link to comment Share on other sites More sharing options...
jpd80 Posted December 22, 2009 Share Posted December 22, 2009 (edited) To the best of my knowledge all Duratec 3.0L engine were/are RFF. The newer Duratec/EcoBoost 3.5/3.7L are DAMB. Duratec 30 was built with RFF and DAMB. Lincoln LS Duratec 30, Jaguar AJ30 and the Mazda version all had DAMB. Edited December 22, 2009 by jpd80 Quote Link to comment Share on other sites More sharing options...
Deanh Posted December 22, 2009 Share Posted December 22, 2009 Duratec 30 was built with RFF and DAMB.Lincoln LS Duratec 30, Jaguar AJ30 and the Mazda version all had DAMB. Scotty...."DAMB it Jim......" Quote Link to comment Share on other sites More sharing options...
theoldwizard Posted December 22, 2009 Share Posted December 22, 2009 Scotty...."DAMB it Jim......" Actually, that was probably McCoy ! Quote Link to comment Share on other sites More sharing options...
jpd80 Posted December 22, 2009 Share Posted December 22, 2009 Scotty...."DAMB it Jim......" Actually, that was probably McCoy ! That reminds me of National lampoon's Vacation - Welcome everyone, I am your DAMB guide, ArnieNow I'm about to take you through a fully functional power plant so please, no one wander off the DAMB tour and please take all the DAMB pictures you want. Now are there any DAMB questions? "Yeah, where can I get some DAMB bait" Quote Link to comment Share on other sites More sharing options...
Deanh Posted December 22, 2009 Share Posted December 22, 2009 Actually, that was probably McCoy ! DOH! Quote Link to comment Share on other sites More sharing options...
RichardJensen Posted December 23, 2009 Share Posted December 23, 2009 That was Homer. Quote Link to comment Share on other sites More sharing options...
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