Sam280Z

I don't think that windshields are tempered. If they were, wouldn't the outer layer of glass crumble when hit by a stone? http://en.wikipedia.org/wiki/Windshield That said, even normal glass is extreemly ridgid. Once it deflects any appreciable amount, it breaks.

Take out the spark plugs so that there wll be no compression. Try to turn the motor over by hand (wrench on the crankshaft pully bolt). It should turn easily. If you put the wrong bearings in, you will have to disassemble and replace them with the correct ones.

Years ago ACT had a problem with hollow rivets stretching limiting disengagement. They subsequently went to solid rivets to fix the problem. I bought one about four years ago which never worked due to the belleville spring splitting in half. I had to spend an inordinate amount of time with their "customer service" to get it remedied. Ended up using a Spec clutch and haven't looked back.

I agree. If you don't care how the car idles or drives on the hwy at low throttle, there is no strong reason to use sequential. However, these are the exact reasons I switched to and advocate sequential. If you are using MS3 - the MS3xX gives you a myriad of additional inputs and outputs besides the ability to run sequential for $90 - quite a bargain. I also agree that you should get good injectors with the correct spray pattern that can be controlled at the pulse widths required to idle and cruise.

It took me a bit to figure out what you had going on with the 0s in the two VE tables. Neat way to use the primary and secondary fuel load. Do you know that you can do the same thing with table switching? (but it would be VE Table 1 and VE Table 3.) Primary and secondary load was implemented more to blend VE values and allow a mix of tuning algorithms. But the way you're using them works fine. In fact, I think you can get an effective 31x31 VE table if you combine table switching with this approach. Although I think your engine only *needs* the 16x16 resolution. Your VE table is pretty flat. I don't think you *need* all those RPM bins. In fact, going to 20psi, you might want more MAP bins. It doesn't look like your version of TunerStudio has table smoothing (last button on upper right of dialog is grey). That might only be available in the betas. It is very helpful. I like to run VEAL for a while and then smooth the changed areas before running again. You end up with a nice smooth table that needs fewer bins. How are you monitoring for knock? A lot of the tunes posted here are for really low compression engines (like 7:1). The most advance I've run is 36deg @ 3000RPM. But that was on carbureted NA engines Something that might help with the idle is turning on the idle advance and idle ve. You can set the curve up to bump the advance a lot at slow speeds and also turn on idle rpm timing correction.

He's using the DIY trigger wheel in the optical dizzy. It gives both cam and crank position.. I see that you are not using the settings for the second trigger active on as shown here: http://www.diyautotune.com/tech_articles/using_diyautotune_nissan_trigger_discs.htm. You have second trigger active on rising edge. I'm using the instructions' setting of Poll level and have it set to Low. Is there a benefit to using rising edge? I'm asking because my tooth #1 angle is at 228deg and yours is at 259deg which are both different than DIY's setting of 345. How did you tune your advance table? Which firmware are you running? Can you post your msq file?

I can't recommend any based on experience. I'm running staged injection. My larger injectors are marginally too large for a good idle / cruise. (I'm using Siemens Deka 63 lb/hr injectors which are good for over 500 HP.) Another thing to look for is a single cone spray pattern. Many newer injectors have a split pattern to spray through dual intake valve heads. This will result in fuel being sprayed on the port walls. Dual cone injectors will work, just not optimally. If I remember, there are some 440 cc/min Volvo injectors that I was considering at one time. They are green pencil style. Sam

Tim, With a single set of injectors that large (I assume you mean 660 cc/min) you will benefit from sequential. It can be done with batch, but I think you will find tuning idle and cruise much easier and get more repeatable results with sequential. Make sure you get high impedance injectors that can be controlled at low pulse widths. Sam

On its own, sequential won't get you significantly more HP than batch. It will let you get much better idle and cruise characteristics when you do things chasing HP that would otherwise create issues in these areas (aggressive cams, large injectors, etc...). It will also allow you to squeeze a bit more efficiency (MPG) out of the motor over batch. I think the MS3X is worth the money, but because of the added input/output channels more that just sequential (although, sequential is nice). Sam

Which injectors are you going to use? HP goals? Additional things you want to control: fast idle, boost control, etc...? I'm using the innovate lc1 and am happy with it.

You really need to make sure that the carbs are balanced - both at idle and at speed. This requires a couple of tools - the flow meter and an adapter: http://www.alamomotorsports.com/weber/synchronizers.html http://www.alamomotorsports.com/weber/STE_40.jpg Out of balance carbs can make one bank run really lean as it attempts to get additional air from the other carb through the balance tube. Air makes it through easily while the fuel has a harder time. THis is most prominent at small throttle openings. You can get an idea of if the carbs are close to balanced by listening to the air flow through a piece of heater-hose held perpendicular to each throat and comparing the sound. I do not trust this method for actually setting the balance. The hose can also be used to listen for vacuum leaks at all joining surfaces. I personally do not have a high opinion of the DGV carbs as they are fitted on the L6. I have had better luck with SUs. Did you rotate the cam to close the valves before you took the wire brush to the head? I doesn't sound like it, but this is what you should have done to protect the valve seats of the open valves. Leak down test will tell you if there is a problem there. You might want to put a vacuum gauge on it as well to make sure you are still getting steady vacuum. I also strongly recommend getting the following books and using their methods for verifying the cam timing: http://www.amazon.com/Rebuild-Your-Nissan-Datsun-Engine/dp/1931128030 http://www.amazon.com/Modify-Your-Nissan-Datsun-Engine/dp/1931128049/ref=pd_bxgy_b_img_y

Can you describe what you did for this repair more explicitly? It sounds like you attempted to remove the head to clean the carbon and tried not to disturb the cam position. Have you verified the cam timing, or are you trusting that it went back together correctly? Did you take the same approach with the carbs? When was the last time the carb bowl covers came off? Are they clean inside? Just because they were working before doesn't mean that they will work now. You have moved them around, possibly disrupting the linkage or loosening dirt that can clog a passage. How have you verified the carb balance? Are your spark plugs tight / wires seated and good? Have you checked your ignition timing? Leakdown test? These are all things I would check based on 25 years of my experience screwing stuff up... If you want to mechanically clean the backs of the valves, the only proper way is to disassemble. Sam

I couldn't tell from your first post what car or engine this was on. I assume you are running 3 or 4 screw SU's? What have you done to verify the tune and balance of the carbs? "If the stock cam has something like .440" lift, .030-.040" reduction in the passage way would significantly reduce airflow in my opinion." While that is true, it will not have a large effect at idle. I doubt the effect is even measurable at idle. Think about it... The only thing that is affecting airflow is the throttle. The engine is turning over slowly, giving the maximum amount of time for the valve to be open. I'm pretty sure your problem lies elsewhere. Sam

I think you are putting the solution before the problem. If I understand your first post correctly, you replaced the headgasket and while the head was off, you cleaned the combustion chambers. Since the #3 intake valve was open, you cleaned it, but did not turn the camshaft to clean the others. Now you have a lumpy idle which you are attributing to the differences in the deposits on the valves. Deposits will normally affect running by absorbing gasoline and affecting the ECU's ability to control the mixture. It doesn't sound like the types of deposits you have are the normal fluffy type that affect engine running in this manner. I don't think that hard, glassy deposits can affect fuel flow or air flow (especiall at idle) enough to cause your problems. I think it is more likely that you have another problem. I'd start with a leakdown test and checking for intake leaks. I think it is more likely that you inadvertently scratched the valve or seat on #3 or have an intake gasket leak. Sam

I'll be doing the fab work myself. I have to build at least 3 right now (2 for my motors). It is definitely not a hollow box. I disagree that the MS3 and 3X is more complex. More expensive, yes. Complex, no. A few extra wires for the injectors and spark and almost everything you will want to add on later is built in. The problem with ITB turbos is that you don't know what you need until you find out that what you have doesn't work. Been there done that. I.e. last major project was welding stock intake flange on to be able to run small injectors at the ports. Check out my build thread: http://forums.hybridz.org/topic/102280-ms3-w-ms3x-install-l6-turbo-sequential-injection-boost-control/ The MAF algorithm is going through a major redesign right now. It looks very promising. http://www.msextra.com/forums/viewtopic.php?f=125&t=50605 James indicates that he wishes to back port to MS2extra as well. Sam

How much of an interest is there in a type 2 knock off and what would be the going price? I have the CAD plans 90% done to build one for myself (CNC and welded). My car was totaled and I was going to do this when I move the driveline over to my other project - but I could accelerate this aspect of the project. I've been keeping my eyes out for a type 2, but they don't come up anymore. I should have bought one when they were $300. Currently running cartech plenum. BTW, I would use MS3 with MS3X. Looking like the new MAF algorithm will be the holy grail... Sam

I just bolted it on. No problems. http://forums.hybridz.org/topic/110340-trying-to-find-a-source-for-15mm-head-gasket-for-l28-turbo/

http://www.shopengineparts.com/parts.aspx?eid=965&cid=24&type=engine&vtype=Import+Auto&make=Nissan&model=L-Series+Inline+6 They say it's not for turbo, but I'm unaware of anything the precludes its use. i'm using one on my turbo motor with no problems. Sam

http://atlanticz.ca/zclub/techtips/hydrauliclifter/lifter+cleaning.pdf

I'm pretty sure while it might "work", i.e. the car will stop, it likely won't work worth a damn and has the potential to be really dangerous. Weight transfer during braking will unload the rear wheels. The much larger brakes back there will be more prone to locking, and without much lighter pedal pressures, they will. Worst case result would be a brake you can't touch without losing control of the car. I wouldn't risk it. If the cylinders are not too corroded, you can stick a repair kit in there for a just a few dollars and it will likely last until April, when you can do it right. Sam

http://www.lincolnelectric.com/en-us/support/welding-solutions/Pages/compact-welders.aspx

miata 2 gauge pod on my 77: https://plus.google.com/u/0/photos/110595327894846974778/albums/5847680414105477217/5850522264572523234?pid=5850522264572523234&oid=110595327894846974778 Used zip ties to close up the back a bit and then used a heatgun to relax the plastic so it would stay that way. Attached to the stock trim piece with 2 small zipties around the back and through a hole drilled in the pod. It wraps around the a-pillar from the glass all the way around the door weatherstrip attachment. Sam

No problem. If you follow the instructions at msextra, it will work.

If you really need it done quick, can you find someone in the area who knows megasquirt and can help you?

Yes it will work like that. Why do you think the wideband will read completely wrong? Most of the fuel injected cars ever produced used batch injection which all fired at the same time (280Z and 280ZX included). The kit you point to is for a DIYPNP controller. It will not work on a regular MS2. But you do not *need* sequential. It will run fine on batch. I understand that you "just want to get the car running for right this minute", but I think you need to stop and do a lot of reading at the link I provided. If you've never done anything like this before you need to get a better understanding of the system. You run the risk of damaging the engine. Worse yet, in the quest to get it done quickly by attacking individual issues as you discover them, it will definitely take longer than if you take a couple hours and read up on of EFI and the specifics of the MS system.