BRAAP

Tony, I’m not trying to be rude here, but you did jump into this thread sort of “screaming” and posting with a demeaning attitude. Lighten up a little and just post your “theories” as you understand them in an effort to convey your idea in such a way that we would want to listen to you, not cram them down our throats with attitude. You will be more successful at getting your point across to others, (whether we agree with you or not), by communicating and explaining your theory, not ranting, raving and acting like a little kid who doesn’t get his way. Rest assured, we are listening and we honestly would like to fully understand your point, but please, quit trying to cram it down our throats, just explain it. As for the topic at hand and your theory that, “if Nissan designed and used a particular component or system, they did it for reason and it should be retained”, I offer this for thought…. On modern throttle valves, early ‘80’s and up, Nissan also added a coolant port to the throttle valves thus pumping 185+ degree coolant through and around the throttle valve. In fact, most, if not all auto makers are also doing this. (We tuners prefer to NOT preheat the incoming air charge). Nissan and all other automakers also installed Smog pumps on Z cars and spent LOTS of money in research and development, parts, manufacturing, etc on the smog pump. (We tuners prefer not to spend our engines Horsepower turning a pump that doesn’t increase our power output). Nissan as well as all other auto manufactures designed and used the EGR valve extensively… (We tuners prefer to keep the intake charge as pure as possible for maximum power, i.e. not diluted with inert gasses, there is already enough inert gas, Nitrogen, in the air that the engine must ingest as it is…). What do these components/systems have in common? They were all OEM designed and installed, with HUGES sums of money invested in R&D, manufacturing, parts, etc, but yet hot rodders from your weekend garage wrencher to your most successful tuner shops prefer not to use them. I think you get the idea I’m trying to convey here. Not ALL OEM ideas and designs are necessary or desirable for a performance engine, and even for some bone stock grocery getters, but if the car is a stocker, no sense in removing it right? FWIW, Rusch Motorsports eliminates the OE external coolant bypass on our engines that we build and/or install for most of our customers while utilizing a bypass such as the drilled thermostat, unless the customer wishes to retain the external bypass, then we leave it. .

Pete Very very nice. Looking forward to seeing more posts when you get it up and running. That valve cover came out pretty nice as well.

Phils head is about ready to ship. Just waiting on the Lash pads to arrive from Nissan, hopefully early this coming week, then a quick cold valve adjust, package, then off to Phil via UPS. This update is the valves, springs, spring seats and stem seals. When installing the valves, you should always use some form of lube on the valve stems even if it is just plain motor oil, we prefer to use high pressure assembly lube on the valve stem before installing. When installing valve stem seals, you want to make sure and use those little plastic condoms that are supplied in the stem seal package, (top picture, middle valve stem). This protects the seal itself from getting cut while going over the keeper grooves. Those little plastic stem covers are always too long so I always just cut it half. When installing these Ford V-6 Viton stem seals, you can use a 3/8” drive, 12mm deep well Craftsman socket to “gently” push the stem seal onto the guide and it will seat with a positive click. Be very careful and don’t’ get the seal cocked on the guide, but “gently” push it on using the palm of your hand. The socket, or whatever tool you are using, should “only” be touching the outer metal rim of the stem seal, NOT on the upper seal portion of the seal that surrounds the valve stem itself. When using the Felpro Viton seals like these, extra care needs to be taken as it is very easy to ruin the seals when installing them. The inner rubber lining of the seal itself can easily get caught and tear and then it will wad that rubber lining up on top of the guide itself causing the top of the seal to bulge out. We’ve had many a so called “mechanic” bring cylinder heads to us that they had just done a quickie valve job “themselves” for a customer, only to find that head they just assembled and installed now smokes terribly and they can’t figure out why. That is when they finally bring it to the machine shop to figure out what they did wrong. Most of the time we find that the stem seal was incorrectly installed, either they forgot to use the little plastic condom and the keeper groove tore the seal, or they wadded up the seal as described above, or they didn’t seat the seal all the way down on the guide itself and it popped off the guide. While on my soap box ranting about mechanics, the other bad habit these same mechanics have is with that scotch brite pad on the end of an angle head die grinder! I can’t remember how many heads I’ve resurfaced because a mechanic got over zealous with his “surfacing disc”. The common excuse given was, he wanted to save a head surfacing fee for the customer who came into their shop with a blown head gasket and thought it was just a bad gasket, (usually there is another reason WHY the gasket blew, but you can’t tell these guys that). They then go on to create another blown gasket as soon as they fire up the engine cause the head surface now has waves big enough on the deck, to surf on caused by their little air powered gasket remover. I’ve had to shave as much as .030” on one occasion to save a young mans attempt at cleaning the old gasket off of the customers cylinder head! He was fresh out of auto tech school and tried his darndest to remove ALL the old gasket material, and boy did he do a good job of removing that old gasket… as well as a lot of aluminum…. I still chuckle over that one… I really don’t have an issue with those buffing discs, we use them all the time. It is “how”, “when”, and “where” they are used that is key. Ok, enough ranting about mechanics. Here are tonight’s pics till the lash pads show up…

Clayborne, Glad we could help. You are welcome to PM or post publicly here if you feel that your questions might be something that would help others as well. In posting publicly here on the forum, you also get benefit of others chiming in with their ideas, possibly covering another angle that I or someone else didn’t think of. You can think of this forum as a HUGE “International High Performance Z car think tank”…. By combining the little bits of different ideas, concepts, and theories that others have speculated over and actually tried over the years, from guys all over the globe, helps shorten the learning curve for those just getting started, and also helps keep the old schoolers on top of what’s “hot” and what’s “not” in the world of Extreme Z cars… There was the Stone age, the Bronze age, the Industrial age, welcome to the Communications, or, Information age…. Isn’t the Internet wonderful?!?!!?

Clayborne, Well, the EDIS will spark the spark plugs al by itself, but the timing will be fixed at 10 degrees advanced. That is fine for starting and idling ONLY! And engine needs more advance as RPMs rise, up to around 3000 RPM or so. Typically between 36 and I’ve seen as much as 42 on some engines. EDIS will allow the user to have pretty much any timing curve they can conjure up, (better to match it to he what that particular engine needs), and as such, you either need Mega Squirt or Mega Jolt Lite Jr (stand alone EDIS controller only), to tell EDIS how much more advance you need, and when. In short, you will be able start up your engine on just EDIS, but if you want to drive the car around, you will need Mega Squirt or MegaJolt Lite Jr to control the EDIS system. Hope this helps…

WOW!!! I absolutely love the visual affect your intake and exhaust system leaves. We always see the polished and chrome parts from everyone else. You know, the “been done before”, syndrome. I personally prefer the more “industrial purposeful racers” look approach to power plant aesthetics, and I truly feel that you hit that mark. From a visual stand point, the wrinkle/satin black, satin aluminum, and gray exhaust wrap combination you have going on is in just the right balance. Gorgeous.

Very nice… We’ve all seen the Polished, or plain Black, Yellow, Red, Blue, etc valve covers. Nice to see some creative paint work being done on the ole Nissan Valve covers. In an effort to make our L-6 valve cover a little different than everyone else’s for our race car, I machined off the NISSAN OHC and then black wrinkle finished the valve cover. It came out pretty nice, but yours is much more stunning. Very nice. Simple, elegant, yet not like everyone else’s… Good work. Kudo’s…. BTW, what dopes your signature mean? "In the last 100 years of Flying, We have Never Left one up there!" As a Private pilot myself, I take that to mean that everything that has gone up, (aviation related since the Wright bros flight 100 years ago), has ALL come back down…. Am I on the right track here?

Just replied to your PM...

Here are some more shots of the valve train set up on Phils N-42. The first picture shows the rocker adjuster bushings being installed and cylinder # 2 with its valves installed using the soft springs. The exhaust valve has a .190” “test” lash pad installed. What we are doing with Phils head here in these pics is setting up the cam wipe pattern on the rockers. Our goal is to bring the wipe pattern to the rear, or the pivot end of the rocker wiping pad by juggling lash pad thicknesses and then fine tuning that by grinding the tips of the valve stems themselves if need be. In the 2nd picture you can see the exhaust valve all set up ready to check the cam wiping pattern. We start out with the Cam manufactures suggested lash pad thickness and then go from there, (we have on hand, one each, of Nissans different lash pad thickness available just for this operation). If the wipe pattern isn’t exactly where we want it, we try either a thinner or thicker lash pad, depending on which end of the rocker the wipe pattern shows up. Then we apply another thin coat of the non drying Prussian Blue to the rocker surface, reset the cold valve lash again, and check the wipe pattern once more. When using the valve seat cutting systems, as mentioned above, the valve seat depths are very consistent and in most instances, we will use only one, sometimes two, lash pad thicknesses depending on whether we had to sink the exhaust or intake valve valves for one reason or another, or in the case of Phils N-42 here, we turned down the +3mm exhaust valves down to +1mm and left a thicker than original valve margin, which in turn alters the installed height, we will then have to use different lash pad thickness for those respective valves. After verifying each and every valve for lash pad thickness, we then engrave each rocker to mark its installation location, as can be seen in the 3rd pic, cylinder #6 Intake and Exhaust rocker, (6I and 6E). This also helps expedite future tear downs as the rockers are now marked for their respective cam lobe. Also, with large cams that have very aggressive opening and closing ramps such as Phils here, the wiping pattern will tend to cover most of the rocker surface as compared to a stock or mild camshaft, which means it is even that much more critical to make absolutely sure that the cam is not riding beyond the rocker pad surface on either end. **update** Remember, lash pads come in .010” increments. Now for the budget DIYer who may only do this once or twice in his life, there really is no need to purchase one of every lash pad for doing this, though you will need at least one solid lash pad, not the OE .120” that has dish in the bottom. Any how, you can use snippets of old feeler gauges stacked under the solid lash pad to simulate thicker lash pads. Get that extra set of feeler gauges from either a yard sale or just buy an extra set from the local hardware store or Sears, they are CHEAP! Using Aviation tin snips, snip a few pieces of .010”. You can snip some of the .020” as well, just don’t get it confused with .010” when doing your measurements. If you think it you might get them confused, then just use as many .010” pieces as it takes. Snip them small enough to fit inside the retainer on top of the valve under a solid type lash pad, (not the stock dished style lash pad). You will use these scrap pieces of feeler gauge to simulate thicker lash pads. I.e. a .160” lash pad with two pieces of .010” gauge underneath is equivalent to a .180” lash pad.. You get the idea.

Wow, sure is a nice looking set up on all levels. Kudos to Jerry for a fantastic looking engine. So is that a harmonic damper built with either rubber or fluid isolated inertia ring or is it a solid crank hub pulley? Thanks for sharing,

We purchased 8 feet of the fuel rail extrusion from Ross machine for a few of our projects including my 240 race car, my V-8 Z, another L6 for a friend, …. If using the Rossmachine fuel rail and the OE injectors with the barbed fittings, there is plenty of meat for threading and for mounting brackets, so you won’t have issues there. The ends of the fuel rail will need to be drilled and tapped for 3/8 NPT or you could use some form of bolt on O-ring plug with fittings etc. I’ve included a couple pics of the Rossmachine extrusion that I machined for our L-28 powered 240 Z race car. I machined the O-ring pockets for the 14mm O-rings and custom fabbed the mounting brackets as well. As Moby mentioned, the O-ring style is a bit more labor intensive, (machine shop work only, not for the garage hobbyist), due to the precision of the O-ring bosses for sealing purposes. I do have enough fuel rail extrusion for another L-6 fuel rail and could build one drilled and tapped with 1/8” NPT for 6 injectors, one or two extra 1/8 NPT ports for anything else like cold start, fuel pressure gauge, etc., and both the ends drilled and tapped 3/8” NPT, for $160 plus shipping. Simply paint and bolt on. I also have a simple tubular fuel rail with injectors for sale that my father put together, it works, doesn’t leak. More details about it with pictures here… http://classifieds.hybridz.org/showproduct.php?product=1813 Our 240 Z race car project… http://www.msefi.com/viewtopic.php?t=15436

Moby, We are all looking forward to reading much more about these MSnS projects. Are any of them going DIS of any sort? I’m sure we’ll have a lot more questions…. Thanks for the update. Our MSnS-E Z car project.... http://www.msefi.com/viewtopic.php?t=15436

Olie, I guess the best answer to your question is, it would take less over all work to bring an N-42 to this level vs trying to do the same with an MN-47. The MN-47 is a round port head. The round exhaust ports, (with the liners still intact), are excellent for mild race and hot street engines. Also of note, All the round port heads, (N-47, MN-47, and P-79), have a smaller intake port. At approx 1/2 “ into the port, the port takes on a “D” shape, this helps bias the port centerline which in turn helps to aim the incoming air flow toward the center of the cylinder. This is great, but for maximum effort high RPM breathing, that smaller port is a hindrance to overall flow. These “D” shaped intake ports compliment the round exhaust ports nicely for mild to hot street, and mild race applications. Especially for a street engine that is asked to have some civility at part throttle conditions like having to drive through town back and forth to work and in stop and go traffic on your way to your favorite bonsai back road. These "D" shaped intake ports and round exhaust ports found on the N-47, P-79, and MN-47, in my opinion, offers the best performance with the least compromise in around town drivability and low end and mid range torque. The square exhaust ports of the N-42, E-88, and P-90, allow for considerable exhaust port alteration allowing the engine to breathe freer at the higher RPMS, though low rpm performance will suffer as a result. The Intake ports of these same heads are also larger than the intake ports in the N-47, MN-47 and P-79, so less carving. In short, the N-42 offers more “all out” potential, but at the cost of low rpm and part throttle drivability. This same radical head on a street engine that is to be driven around town would be a poor choice. This N-42 works best at WOT and above 4000 RPM, where as the round port heads do their best, (depending on how they are set up and built), from as low as 1500 RPM up to 6500 and will have decent manners around town. Here is a MN-47 in the "rough in" stage of chamber work. This MN-47 is going on Roger Waylands hot street L-28 powered 240 Z with an Electromotive L-7 cam and Triple Webers.

Currently 34 cc, will be between 34 and 35 when done.

Dave, With the cutters, some shops don’t lap as they feel there really is no need if the valves are sealing, (vacuum tested chambers). On all of our high performance head work, I do give the valves a quick lap. It doesn’t take long to do and this process also gives the builder a visual indication of the actual contact area between the valve and the seat itself.

On a per quote basis, Hahhahha But for you Cary?… I make vety vety special deal… Hmmm.. what are up to Cary? I can’t imagine you’d let someone else do your L-series cylinder head work?!?!?! You’re the type that does all his own work, especially really "creative" L-series port work…. Contact me off forum…

This started out as just an update on one of our own Hybrid member’s custom N-42 race head that we are currently working on turned into an informational session for those of you who don’t know what’s involved or have never seen what goes into building a custom L-series cylinder head. This is not a complete, concise progress report, by far, but it does highlight a few key elements that go into custom cylinder head work. Phil Reith, a member of this forum, was kind enough to allow us to photograph and document the progress of his cylinder head and make that progress public. Phil is having us build him a custom N-42 for his N/A road race project. This N-42 head started its new life having another shop in Phil’s local region perform all the initial welding. The injector ports and injector mounting holes have all been welded in. The center exhaust ports have had the outlets welded to more closely mimic the outlet size and shape of the other exhaust ports and the chambers have been welded in as well. Then Phil shipped the head to us for us to wave our magic wand over it. Immediately, we started out rough shaping the chambers, and then we had any deficits of material filled in by Russ Meeks, a local hot rodder here in Portland who performs our aluminum cylinder head welding. Then we replaced all the valve guides and seats, and gave the chambers a final rough shaping. This is where most of the work lies in the chambers and exhaust ports. Many hours of grinding, carving, shaping, measuring, checking, and carving some more go into this. Then we removed the press-in oil galley plugs, drill and tap them for ¼” pipe plugs, being very sure the front galley plug does NOT stick out into the path of the timing chain. We then go inside that forward oil galley and slot it accordingly to make sure the new screw-in plug doesn’t block off the front cam tower oil feed. Then we re-tap and chamfer all threaded holes. Today we just finished up with all the valve seat machine work including 4 and 5 angles on the valve seats. The valves themselves received a 30-degree back cut, and the heads of the exhaust valves have all been radiused as well. For valve-seat work, we only use Sunnen VSC seat cutters. Valve-seat cutting systems, like the Sunnen set up (there are other seat cutter systems used in other shops that are comparable) offer the highest quality and most consistent valve seat work available. The old hand held stone seat grinders are a thing of the past. The carbide cutters of these seat cutter systems have all three angles ground into them, with different valve face widths. For N/A engines, we use .040” intake seat widths, and .060” exhaust widths. We then set up the actual seat diameter as wide as we can, to the valves being used, without compromising valve face margins. This usually allows us to open up the ID of the seat itself using the Sunnen “bowl hog” cutter since the OE valve seats typically are slightly smaller than what is optimum for air flow. From an air flow standpoint, this is effectively like going to a slightly larger valve without the larger “valve head” shrouding the valve to the chamber wall. Of course this is a minor improvement, but every little bit helps. In the case of this custom N-42, the intake seat ID’s were opened up approx .5 mm more than OE, and being as the exhaust valves are 1mm larger, the effective seat opening is now approx 1.5mm larger than it used to be. We then go back after all the seats are cut and add the 4th and 5th angles, if space allows. Typical L-series heads receive at least 4 angles, sometimes there is room to get that 5th angle in. Each and every seat is EXACTLY the same width, diameter, and depth as the other corresponding intake and exhaust seats within the head, and all seats are concentric to the valve guides within .0005”. We use the Sunnen seat cutter system in conjunction with a bridge port style mill, and as such, we “dial in” and LOCK the cutter head to each and every seat exactly to the valve guide angle in both “X” and “Y” and then center up on the guide itself to within .0001” to maintain valve seat concentricity for 100% valve seal. Just to be sure that we have that 100% valve seal, each and every assembled cylinder head has its combustion chambers vacuum tested to verify 100% valve seal before the head goes out the door. If a valve doesn’t seal 100%, the head gets torn back down and a thorough inspection is performed to identify why that valve isn’t sealing and corrective action is taken. Then the valve seal is rechecked. The Bridge port mill does take a little longer to get the cutter set up to the valve seat as compared to the air float seat and guide machines using the same cutters, but the Bridgeport mill is more precise and more stable than the seat and guide machines. In my book, that extra time spent setting up on a Bridgeport is a small price to pay for a higher quality valve job. These pictures are of PReiths custom N-42 head during the seat cutting stage, (seat cutter can be seen in the pics hovering over an intake seat). The chambers will get a final surface prep, (they will look much nicer than this when done), the head will get a final surfacing, then the chambers will be CC’d to within less than ¼ CC of each other. During the initial seat cutting on cylinder heads such as this, which are utilizing a big lift cam, we will cut only one intake and one exhaust seat. Then we install an intake and exhaust valve using our “soft” springs with the retainers and keepers that are to be ran in this head. Then we measure spring installed height, retainer-to-valve stem seal clearance, etc, and make note of anything that needs adjusting. Then we go back and cut the valve seats to the depth that offers the least compromise without having to sink the valve too deep into the head. This allows adequate retainer-to-stem seal clearance and installed spring height. We also use spring shims of varying thickness to help adjust spring-installed height in order to maintain correct seat pressure. There are also a couple other techniques we will use to achieve more retainer-to-seal clearance such as machining down the under side of the retainers, but only up to within .010” of the keepers, no further, just as we did on this set up (see pics below). FWIW, the Fel-Pro Ford V-6 stem seals allow for considerably more retainer-to-seal clearance (the valve spring retainer “WILL” crash into the valve stem seal with big lift cams), and the Viton rubber is much more resistant to degradation over time vs. the OE style polycarbonate seals. These pics show the retainers as originally sent to us, and then modified by removing .050” material from the bottoms allowing for another .050” clearance between the retainer and the valve stem seal. This also lightens the retainers just a smidge. Note, the shorter Viton Ford V-6 stem seal next to an OE style polycarbonate seal, height mic, various spring shims, etc. We hope you all enjoyed this little peek into the world of custom cylinder head building…

I’ve been seriously eyeballing those same throttle bodies myself at the wrecking yard lately. Ron T. is contemplating them for his wifes L-20-B 510, (his MSnS-E experiment,.. for his E-30 BMW M-3) But of course Bryan isn’t revealing his OTHER really cool intake… at least not yet, that is…. MUUhhaahahahaha BTW Bryan, nice work on this intake. Very sharp.

LMAO… You’ve been reading TOO much KIT-PLANES!!! (Great magazine for the aviation enthusiast by the way…) In all seriousness, I have been contemplating a Vans RV kit or the Zenith CH801 with a either Eggenfellner Suby or one that I personally build… http://www.eggenfellneraircraft.com/ http://www.zenithair.com/stolch801/index1.html

When we originally did Daves Rack & Pinion on his VG30DETT 510, Drax240z conversion was pretty much how ours turned out, complete 240Z front suspension, including rack, cross member, struts, steering knuckles, etc, though our T/C rods ran back just like the Z car. This required notching the frame rail to accept custom built boxes that the T/C rod pivot attaches to. We then used some plate steel that bolted to the bottom side of the strut tower and the Z strut hat attached to that. Dave has since altered the suspension to some degree, maybe he’ll chime in and tell you the latest details of the current set up. DRAX, just curious how you dealt with clearing the rack & pinion tie rods with the forward facing T/C rods?

Yeup, Darius work. Darius car is one of the wildest. His diffuser is beautifully done. Patzky, so you’re a pilot? What ratings do you hold? What birds you normally fly? Private license here, SEL. C-172, C-152, Piper Cherokee Warrior . Also have an hour in my neighbors Grumman Widgeon