BRAAP

Chewie, You are thinking in the right direction, though that route to your good idea is probably not the best way to achieve that ideal port. To fill the coolant passages and reshape the ports would work from an airflow standpoint quite well, but the engine wouldn’t last as the combustion chambers now have no place to dissipate the heat to. There is another way to achieve the results you are asking about and this topic comes up once in a while in causal bench race sessions. I have seen pictures of an L-series race head, (I think it was in one of the how to modify and race your Datsun books), where the entrance for the intake ports were raised substantially. They were raised up to the valve cover rail, maybe even were raised up into the valve cover if memory serves, in an effort to straighten out the port which is less restrictive than a curved port. It was over 10 years ago the last time I saw that picture. Anyhow, in carving out the region around the ports to that extreme and rewelding in new port walls so to speak, (tubing, or just building/welding the port walls up), there “should” be no cooling issues, (other than any that currently exist). Recently, there has been talk of taking an existing head and raising the intake ports substantially as well as the exhaust, requiring extensive hacking and welding to this poor existing head. I feel that when attempting to go to this extreme, that every aspect for improvements, such as the port shape, size, taper, etc, from the valve seat to the manifold mounting surface should be taken into consideration. As you stated, this would really only benefit full tilt mega RPM race engines. Maximizing the ports as they are currently cast, (i.e. no welding or building up of new port walls), I feel will get 95% of the extreme guys approx 90% of what the two valve design will allow. Going for that extra 5-10%, would require an awful lot of hacking, welding, and machining and it is still just a 2 valve head, (not that there is anything wrong with that). At this level, with so many 4 valve inline 6 cylinder engines readily available, (and other engine choices), you have to be really dedicated to the L-6. Though I do feel this extreme L-head should be built at least once if for no other reason than, we can! Here is an example of optimizing the existing intake port entrance by essentially raising the roof without taking any material off the port floor. This custom Rusch Motorsports N-42 head has extensive valve unshrouding and extensive exhaust bowl work as well, yet no welding or building up of the ports. With a mild .465” lift cam, Ron Tylers custom intake manifold, WOLF 3d EFI and DIS, this 8.2:1 compression L-28 pulls through 7000 RPM. Now we just need to build this customer a solid bottom end with some compression to match the head, cam, and induction.. Here is a link to that project… http://forums.hybridz.org/showthread.php?t=117607

Ron, Don’t you have some pressing EMS questions to answer, coil brackets or diff mounts to design? Oh, don’t forget… Ferraris are RED- Ford emblem is… blue… Hot chics wear RED dresses, Monica Lewinsky wore BLUE. Coke-a Cola over Pepsi. Killians RED over Pabst BLUE ribbon

Hmm.. Sounds like the old school Mechanical injection, ala Kinsler, Hilborn etc.. Do you have any more info on this?

Chewie, Are you talking about using something like Block filler to fill up the coolant passages in the head and then carving out the ports to something more optimum in shape and size?

Dad gave me the…. Keep it up and it’s….

Cary, What about the standard WRX, did they come with the R-160 or R-180? Those STi R-180’s. Are all those LSD? Is the LSD clutch or Viscous? What ratios, any 3.36 or please oh please a 3.15? What about frogs?

I have also heard that the Q came with the R-230, though I’m not sure what years or models. I do know that the ’96 model year Q-45 has the R-200-V. My ’96 Q-45 has the R-200 V and according to my factory Infiniti Q-45 service manual, all ’96 Q’s have the same R-200-V.

This “$#!@” of a “$@&^” is “$^&!*" biting “*#&$%” …and add a few other colorful metaphors. Not fair. Terry posts a video with a car that has a HybridZ plate, the subject line says it all, and I have to wait till tomorrow AM before I can see it!!!! Our darn satellite is on the fritz right now, (DIRECWAY SUCKS!! This happens on occasion for 24 hour stints), so I’m stuck with Dial up at 26.4 Kbps connection speed, till tomorrow AM!!!! Larry, Is the rain affecting you in any way? I’m hearing it should let up for the 4th.

Whew… Thanks guys for jumping in on this one. Too many unknown left out details for one guy to diagnose. I think he is relatively new to automotive and Z car mechanics and I was beginning to think I was all alone in helping him. A couple more of these chasing our tails posts and I was considering tool shedding this thread and just sending him a Haynes manual.

Ron, I think the “pile” he was referring to is "your car"…

Just ran across another interesting tidbit on the Cerbera V-8. Apparently the cylinder banks are not Vee’d at 90 degrees, but rather at 75 degrees, which would make it an odd fire V-8… Hmmm.. Unless they manufactured the crank with the crank pins off-set 15 degrees, (like the GM 4.3 V6, Buick even fire 90 degree V-6, etc) .. Hmm…. Can anyone dig up a picture of a Cerbera single plane crank? (I don’t trust the details 100% in tech articles) http://www.pistonheads.com/tvr/cerbera/faq.htm

The only options I am aware of to retain the OE hood latch is convert to DIS, install an LT 1, A Scarab type conversion, (the SBC is mounted much further forward), or SBF, (or other front dizzy V-8). Personally, I think a dual latch set up such as the Vette uses, would be nice, no idea how much hassle it would be to install on the Z car… Or just us the JTR hood latch idea. It works and works well and with some creative work, grinding etc, I'm sure it can be made to look OE.

You know IR manifolds are my favorite don’t you. .. The only thing I would change about the Yellow cars intake is, I would add another pair of air horns...

Ok, well first find out where your clutch fluid went, (leaky master cylinder, cracked flex hose at the tranny or leaky slave cylinder), then when you get the clutch operational, try swapping out the starter. I just had a thought. When you were cranking the engine with starter, during this eissue, was the car in Neutral? This is only relevant due to your lack of clutch fluid…,

Do you have an RB conversion in your 280-ZX or is it the original Datsun L-28ET? In regards to the L-28, (could apply to the RB as well), are you sure it is starving of fuel and not being excessively fueled? If is it being excessively fueled, evidence will be black smoke from the tail pipe and black sooty spark plugs. I say this because a very common typical issue is the connections for the OE water temp sensor commonly have issues, corrosion, etc. If the ECU sees infinite resistance, (an open water temp signal to the ECU, not to be confused with the water temp sender for the temp gauge, separate sender all together), the car usually starts fine, but as the engine arms up, it runs worse and worse from being pig rich, i.e. too much fuel. If it is starving for fuel, look for vacuum leaks between the Air Flow meter and the intake manifold and check all other vacuum lines that come off the intake manifold.

A quick use of the Hybrid Z Search engine brought up several threads regarding Datsun 6 cylinder firing orders. I’m feeling nice today so I’ll throw you a bone... Firing order for all Datsun L-6 engines is 1-5-3-6-2-4. With the #1 cylinder at TDC of the compression stroke, the dizzy rotor should be pointing towards the front of the car. The rotor spins counter clockwise. This site is a wealth of information and the people are friendly. As such, before posting general simple questions, please do a search using the search function. Makes better use of the available bandwidth when that question has already been answered before. Thank you, Paul

The last couple years of BMW cars have taken on a rather Korean-esque auotmaker appearance..

That car is truly a stunning example of excellence in design, style, and engineering, as implemented in a Z car. Thank you for sharing John.

Very cool. Thanks for sharing. They sure like Nitrous over there. Don't see much Nitrous run on L-6's over here...

You are correct in that an engine can function without an idle speed controller, whether it be a stepper motor type or the bimetal strip type. For a street engine, you will be compromising either cold running idle speed or have a high engine idle speed when the engine is warm if you eliminate the cold idle speed compensation. My personal L-28 Z aka BRAAP, with the stock EFI, ran without the factory idle speed compensation, (the air flow regulator). I then used the set screw that adjusts the throttle plate “closed” position to a point the engine would idle where I wanted, reset the TPS, and that was it. Now in doing this I made a major compromise. That was when the engine was full warm, idle speed was between 1000 and 1100 RPM. When the engine was full cold on a cold winter day, say 32 degrees, upon initial start up, the engine would barley idle on its own at 500-600 RPM. Fuel injector pulse width was optimized for AFR only. Another example is my L-28 Mega squirt EFI race car. I did the same exact thing, no idle air controller. Difference there was I utilized a later 280-ZX remote idle speed adjuster attached to the bottom of the manifold instead of just adjusting the throttle valve “closed” position. I set the warm idle speed where I wanted it, and that was that. I had to baby sit the gas pedal on cold start for a couple minutes till the engine warmed up to the point it would maintain its own idle, small compromise for race car. In both scenarios, I only adjusted the fuel injector pulse width for a stable idle. With Mega squirt on the race car, I used our LM-1 and dialed in a 14:1 AFR. Here is the BRAAP car… Here is the Race car…

AH... Yes, I stand corrected. Prior to the tall ratio diff, (between the trans and diff as you stated), the torque loads would be substantial.

It will clunk as you load and unload it, i.e. on and off the throttel, just like a bad U-joint that has a lot of slop in it.

Thank you guys. The red badge is truly an honor.

This is one of my favorites. Renault F-1 engine on the engine dyno simulating the car being driven around the Italian circuit, Monza. The mixture cloud standoff from the reversion is just cool.

This sort of follows the theme of this thread. Motorcycle powered cars. (Super bikes have the exotic exhaust note we are after, right?) Lots of cool wicked quick cars and links.. http://thekneeslider.com/motorcycle-powered-cars/