Tony D

The costs of the triple carbs are now almost identical to a set of ITB's. Comparing stock EFI plenum to Triple Mikunis or DCOEs is a serious 'apples to oranges' comparison. The dyno sheets WERE up here, in regards to our Bonneville L28, which ran, in turn, a Predator Four-Barrel, 45DCOE's, and then TWM ITB's. In each iteration there was an increase in power and civility of the exact same engine--a very important fact to realize is ALL that was changed was intake type (the TecII Ignition merely ramped identically to our recurved distributor): The Predator made 217 Hp and just didn't pull well over 6,500 rpms, it idled at 2,200 rpms. The 45 DCOE's made considerably more HP, with a power peak of 7,500 rpms, it idled at 1,700 rpms. The 45mm TWM ITB's made 17~20 more Horsepowerthan the DCOE's at 7,500 rpms, and 40 HP More at the new power peak of 8,250 rpms. Idle was wherever we wanted it: it would pop along at 450 rpms, and start easily in 39F weather on a 1,900 fast idle, and come down as it warmed up to a curbe idle of 950. This can be attributed to pumping loss restriction? Below 6,500 a four barrel seems to be competitive, above that Triple ITB's or DOCE/Webers are the power kings. You will always need a larger carb to get the same HP as an ITB. We could have made this same power with 55 DCO's, but they would NOT have been applicable to run on our L20A later when we switched classes downsize. That's a lot of money to pay for something you can only use on one of two engines you have!

Anecdote: When Don was alive he was found by many to be somewhat...uh "Abrasive"... In fact in the old Z Car Magazine he had a column which was proudly "Curmudgeon" or something... I approached him at MSA back in the 90's as well, as someone pointed to him and said "he can recurve your distributor"... I went up and introduced myself and said so and so said you can recurve my distributor, what are we looking at for pricing and lead time? "$476, and when I get to it, you'll get it." And back he went to his conversation. "OK, fair enough" thought I... Poking back into the conversation I merely added "Do you have a card or something so I can call you later and make arrangements?" He seemed a bit shocked, but handed me a card and went back to his conversation paying me no more mind. So I called him two weeks later, told him who I was...we started talking about the build, what I wanted, yadda yadda yadda and somewhere in there I mentioned "I kick myself in the ass for ever selling my SUN Distributor Machine, for what I would have paid to ship it I could just do this myself and not wait..." Don asked quickly "You had your own Sun Machine? Why?" I explained we had one when I trained back in Michigan, that I got a deal on a surplus unit at a military disposal auction but sold it, a Sioux Valve Grinding Machine, and one of those old Sit on the Block Top Boring Bars back to another fellow bidder with a shop because I was hopelessly overweight on household baggage and was maximizing my weight on Datsun Parts and not machine tools which I convinced myself were plentiful in the USA... "So much for that stupid decision." Ended up talking to Don for about two hours and in the end he says "What did I tell you for the distributor recurve?" I said "$476" He just started laughing..."well, I was right again!" He apologized saying he gets approached all the time at car shows from guys with grand ideas but who just want everything for free. He says "I got a set of weights here, should be just what you need, give me your address and I can get them in the mail tomorrow." $20! Came in a heavy business envelope with three stamps on it. "DPE, Milpitas" was the return address. And he was right, they were spot on what I wanted them to do. In so many ways I watch this exact same scenario play out on internet boards to this day and think "Man, if I acted like these guys today, I'd have lost hours of free advice and discussion with a veritable L-Engine Genius!" I mean, once he determined your bonafides, he opened up quite a bit especially if you were not a competitior and understood his side of the business and people always ripping him off (which I understood all too well!) When we took over a distributor there in Milpitas and they made me interim service manager I was almost jumping out of my skin to go...all after work was 'see if I can get over to Don's' just to talk about nothing in particular. Just hang and hope for osmosis to kick in. It was a sad day when he passed on, we are all less without him.

This is how you lift a head off with a helper. Installation is the reverse of removal. Note assistant was present to photodocument the process. This really should be put in the FAQ, the pictures make it so much clearer, huh?

THERE we have the answer. You're fine, you just have to lift it level... if you tilt, it will bind. I've never pulled the studs to remove the head, it kind of defeats the purpose of having them there in the first place! LOL Oh, I got a photo for this comment regarding a helper... Let me get my phone and see if I can attach it... mowhahahaha!

it's all a nice exercise... Have titanium valves, retainers, spring keepers? Well then lighten that reciprocating end and run a lighter spring, you might be good to 24,000 rpms! stock nissan rockers on our bonneville engine were stable to 13,000 rpms in our testing. I think valve, spring, and cam profile selection play a much more critical role. If you note the E-Motive guys polished theirs similar to TimZ. We didn't even do that, though I have in the past on other engines (Yamaha....)

Did you feel that resistance on your head on installation? I've taken mine on and off for tech inspection I can't count the times and not had this issue. Was the head warped from overheating, possibly?

I sent you a drawing of the groove we use for the static seal on our gearboxes. Captures the O-Ring in whatever component you want to machine the groove. Ip to you if you want to machine the head to hold the O-Ring and keep a simple flat valve cover, or vice versa. When I get the O-Ring spec drawing I'll let you know--that way you can scale what you have to whatever O-Ring you decide to use, wherever. Seems to keep the throw off from the pinions at bay, they're slinging oil out at 45,000+ rpms directly at the splitline joint!

Derek, Is the valve cover O-Ring Groove square or trapezoid? Our gearboxes use a trapezoid cut o-ring groove on the splitline. We can do that easily because the cutter can enter from multiple points around it...you would have to plunge in and go... That trapezoid holds that O-Ring in place so you really don't have to glue it except around 25mm at each endpoint where oil can enter from the gearbox. I would assume with this one you could either superglue the O-Ring stock and then put it in place or maybe butt the ends and apply a dab of Loctite 598 / Permatex Ultrablack to seal the oil intrusion point. It makes it kind of nice as you lift the cover off and the O-Ring is held fast and doesn't fall all over stuff.

sorry, missed all of them. You can plug both the bypasses and plug the heater core fittings as long as you use a thermostat with a couple of big holes in it, a bypass cooler setup, or provide for circulation of the pump while it's warming up. On a race car, a restrictor plate or double 8mm hole in a standard thermostat should provide more than enough flow so the pump doesn't cavitate at startup cold and pump dead headed into the block. The idea is to give that flow somewhere to go, and in this case, it goes to the radiator so you end up heating up ALL the water in the system, instead of just what is in the block (internal recirculation till thermostat opens) so it takes a bit longer. Just idle it in the pits with the fan off or cover a bunch of the radiator with cardboard to bring it all up to temperature before putting any serious load on it. An easy lap around most tracks gettting the tires up to temperature will accomplish this. I try to keep a thermostat in most things unless it's all balls out racer that sees idle for warmup and 3500+ the rest of the time. Removing the bypasses and plugging the flow to the heater will insure 100% cooling capacity is available for the engine. It's obligatory on 300 hp, at 200 you can still run a thermostat with the two holes punched in it (or a -6 bleeder line from the lower thermostat housing to the radiator hot tank) to keep the flow and prevent cavitation. Bluntly, the heater and bypass represent shunts of the radiator, and decrease total possible heat rejection. The bypasses should be eliminated in all racing cars for maximum cooling. Heater with a core, yes. NEVER loop it, PLUG the holes like when the heater valve is ÖFF"! Good Luck

I have always used pump outlet/block pressure which should be identical. The problem using above the head gasket is that the orifices restrict the flow and you don't see the pump cavitating, and in most cases the thermostat is wide open so all you get is cap pressure which can be maintained with quite a bit of coolant loss. There is a block drain fitting on the left side at the very back. That is where I put my block pressure line. You will see it flutter and drop when your lower radiator hose collapses from suction out of the radiator, you will see flutter when it cavitates. It will be an interesting learning curve.... Absolutely though, if you cut a hose and start pumping coolant out, you will see that go to nothing fast. Some people put a hobbs switch in that sensing point that triggers below cap pressure (and you bypass it with a rocker swtich during warmup)... It can ground the magneto, kill the ignition, light a big red CHECK WATER light...whatever....

The 240Z is what we in the Export World called the Fairlady Z... Only 417 of the Fairlady Z received the S20 DOHC, and they were referred to as "Fairlady Z 432... There were Fairlady Z's, and Fairlady 240Z's, and for a short time before recall Fairlady 260Z's. The Fairlady Z was the SOCH 2.0 Liter Japan Market only S30... Where it all began. It was a continuation of the Nissan/Datsun Sports Car Line started in the early days of the company, and which received the ""Fairlady"appellation in the 1950's in conjunction with the release of the movie "My Fair Lady"... True Story.

REALLY APPRECIATE THE UPDATE! Like anything else, government meddling drives up prices. Most of this is recordkeeping and compliance burden. Given what it removes 9every bit of rust...man... Almost worth a U-Haul and the Gas to Phoenix for a Drop and Pickup, huh?

His brother posted the Obit on FB earlier, with service details for those in the local area: http://www.memorialsolutions.com/sitemaker/sites/JOHNSO8/m/?p=memorial&id=2024962

The Eurospec L28ET was factory rated at 200 bhp with 300.000 mile reliability. I think 200 hp is well within the realm of safe engine modification.

This is the wonderful advantage of an RHD Car, just keep that window closed and kick it out the left side!

Just remember this, optimal face size is 35mm. You can flow 230cfm through that face juncture. If you are porting so the injector notch isn't showing anymore, you're doing it wrong unless you're running 55 DCOE's. Even then, head juncture is 40-43mm and the notch still exists. What evidence to prove the flow is hurt by leaving those notches in there? I'd like to see it other than just someone claiming "it makes turbulence" especially in lieu of the fact that dyno numbers show the SCCA allowable "port matching" on the manifold and head 1" either direction of the gasket surface doesn't reap any performance reward, but if done improperly can hurt performance. The flow is in the bowl and short side radius, not the diameter of the runner or removing injector notches. 35mm is more that big enough to allow most triple manifolds to taper no more than 7 degrees to hit the throttle plate diameter at the carb/manifold flange. Proper angle-tapered porting of the Triple Manifold is more fruitful, depending on which one you have. Most for L28's now come near 35mm already and have the proper taper from 40 to 35 or 45 to 35 at the head flange.

An adjustable gear may move it up somewhat, but there likely will be a torque tradeoff made (it will be peakier, loss at the bottom). There is only so much you can do with the L28 cam which peaks at around 5300. An L20A cam, or L26 C cam was the hot ticket from my recollection. They will pull all the way up to a power peak at 6500. The difference in the two, you see the characteristic HP curve is very similar, timing will move it left or right, not up or down. The torque curve is the same, it will move SLIGHTLY upward, but there will reach a point that the bottom end just go away completely. The torque is VERY dependent on proper timing events. It will move a LITTLE, but it will get peakier. The HP will move somewhat left or right...we are talking 2 to 4 degrees max. It appears run 12 had a better, wider torque curve, and the HP curve was proper. The Red Traces though higher and WAY to early, and my bet is you will be able to move them where the blue traces are, without affecting much on the bottom end, the torque falls off WAY to early on the blue traces as does the HP. I think the timing is slightly off, maybe 2 degrees. Get that adjustable cam gear and get the events proper...or just reference it, and then go 2 degrees one way, and 2 degrees the other. That will show you which way will gain you what you want.

It bears repeating my DCOE N42 experience with the butt dyno... With the 40 DCOE's and header it sounded great, FELT fast as hell, but dynoed at 87RWHP Changing ignition leads, putting an all stock 76 EFI system onto the car (including stock exhaust manifold with MSA downpipe to the same 2.5" Crush-Bent Exhaust) and changing plug wires with the stock air box and K&N filter in it had EVERYBODY saying the car was "torquey at the bottom end" and "fell off up top"... Consensus from multiple Butt Dynos was the car was more tractable due to the torque, but wasn't as 'fast'... Of course, it also Dynoed at 147 RWHP at the same shop and same dyno the DCOES were set up... Now, the DCOE's were NOT optimized. But the sounds and the WAY they seemed to have an "on-off" switch throttle response convinced EVERYBODY including me that they had gobs of power over a stock setup. Of course, and properly set up DCOE set should make more...but the point of this post was the butt dyno was worthless in any manner of empirical evaluation and gave universal 100% incorrect feedback. :

Rayjay external wastegate worked OK to limit boost to around 12 psi. It was connected off the brake booster line with a "T" before the check valve. A boost controller in that line usually had a bleeder hole upstream from the ball-check adjustable controller and the wg actuator... You definitely want to limit it, that turbo will go to 21 psi without a problem, and quicker than you think! The hole was for the carburetor de-icing on the Carter YH that normally bolts to the front of that turbo. In cold or even cool areas with any kind of humidity at partial throttle, especially off-idle the original one-barrel would ice up like a big dog without exhaust heat circulating through that tubing and connected to those two holes! Carb sucked air in from the air cleaner, through that base plate, and through the carb base. Welcome to using parts from non-watercooled engines! ;^P

Run off to the jungle to get chimps throwing crap at me through the fence, work 176 hours, and come back to find all this...

There is a smog forum for california legalities. Guys with supercars usually have the means to not worry about a $1,000 deductible. In the Datsun world, most of these owners are one paycheck away from selling the project to make rent or eat so playing fast and loose with insurance than can say "denied" and not even pay out $2,500 for a decent replacement junker to roll in and get to work can suck bigtime. Yeah, you can get a 'garaging address' where they don't do smogs, and send all your documents to that address (CA plate renewal, new registrations and stickers, etc...) but for all that matter if you are circumventing the law why the hell would you want to pay CA prices for essentially saying the car is in LA? May as well retain the LA plates until MADE to change them. Insure it there, register it there.... all depends if your job needs you to have a CA license or not.

Everybody is an expert now, thanks to YouTube and Herocam!

Nissan Legal wanted at one time to sue all the Z-Car Clubs in the Nation because of the very same issue. These are the same people who tried to trademark the letter "Z". They have lawyers, money, and time. Gotta dance the dance and not use their trademarks unless you have that little disclaimer somewhere in the ad you always see (the words 240Z, 240SX, blah blah blah indicates only suitability for application and not an endorsement or whatever they always write by Nissan, Nissan North America, or Nissan Motor Corporation... Welcome to Murrica! Don't forget the fight Mr. Nissan had with his websites that predated the Auto Manufacturer!

Oh, and if the thermal switch is turning your fan on later than 175F, its likely too late. If you have read my prior posts on e-fan setup, the above test to determine slowest speed stable temp you get on a hot day dictates where your fan turns on so it's not running while going down the freeway or even in city streets. It will only come on in stop and go and come on early enough to prevent nucleate boiling from starting and becoming a problem. I set mine to turn on 10F above where my temperature stabilized on that 110F day, right around 175. I could see the temp rise on the stock gauge, hear the fan kick on and watch it go back to lower temperature then shut back off. Cycled nicely in stop and go, and has since 1990!

I got to mention on the Engine Masters that they don't discount the slippage on the Nissan unit. The fan blades are at a governed speed. That is why they come up with a whirr and then stablize flat in pitch and noise. Unless the engine is uphill in the summer towing a load and radiator temps get hot enough to reengage the slip clutch it will not take over a given horsepower.... That said.... Do you still have the 160F thermostat in it? If you are reaching 195, where is this measured and on what kind of gauge? What PSI is your radiator cap, and what is your glycol/water mix percentage? In short, with a 3.36 rear gear, in fifth gear WITH NO FAN WHATSOEVER, running 30 mph, on a 110F Palm Springs Day, your engine should run 165-170F with a 160 thermostat. If it doesn't your system is deficient in heat rejection or circulation. Do NOT loop the heater core. Plug it. Do not let the external bypass line stay open in hot weather. You should be able to cool a stock or even hot rodded engine of 250 hp with a standard three core copper and brass radiator. The biggest thing you can to to suppress nucleate boiling is to run a higher pressure cap. 16 is a minimum, but a 24 or 30# cap will keep the steam from forming pockets and causing a runaway overheating issue. Now, you state 'overheating' but 220 is warm...not necessarily overheated. You need to specify which thermostat you have as the temperature at the back of the head will be 15-20F higher than what you sense at the thermostat outlet at the front of the engine. This is why the back cylinders detonate so often. Most curious on where the temperatures are coming from...either I missed it in reading the thread, or it hasn't been mentioned.