ozconnection Posted September 27, 2009 Share Posted September 27, 2009 For those of you who don't know me, I'm running an L28 N42/N42 combination, mostly stock with a header and a 2.5 inch exhaust, stock cam, four barrel Holley and a 280ZX dizzy with an MSD 6AL. Stock head and compression. I changed over intake manifolds from the Arizona to the Nissan E32 four barrel intake. Virtually a straight swap, it took about an hour to do the lot. Very straightforward. The only difference is that with the Nissan manifold, I reconnected the under plenum water heater arrangement whereas I had left it disconnected with the Arizona. The Holley required some slight tuning to match the new manifold but the mixtures are as they should be, verified by my Innovate WBo2 data log. Now here is the issue, the Arizona could run with up to 17 degrees static timing. The dizzy puts in a verified extra 20 degrees, so it was total of 37 degrees BTDC @ 3500rpm. Premium unleaded, 98 octane/NGK BP6ES-II. With the Nissan manifold, I've had to back off timing to 7 degrees BTDC, 27 degrees total @ 3500rpm. Changed the plugs to BP7ES at 10 degrees but it still pinged, hence the drop to 7 degrees. Now it doesn't ping. Lost some top end power, but the midrange still feels ok. Why did this happen? Intake manifold too hot now with the water heating? (Fantastic start up though....just bump the starter and it bursts to life....very quiet idle, quite docile at low rpms, still loud at WOT though!) Outside temps hovering around 18-20 degrees celcius, not hot at all! Your thoughts and/or ideas? Cheers! Quote Link to comment Share on other sites More sharing options...
kolonelklink87 Posted September 28, 2009 Share Posted September 28, 2009 is there stock heat sheilding on the bottom of that manifold? I've still got some alloy lying around if you want we can cut some up for the job? the heat question could maybe be answered with a themometer gun thingo... michael has one... let me know and when you're east-ways next i'll get it off him. Quote Link to comment Share on other sites More sharing options...
ozconnection Posted September 28, 2009 Author Share Posted September 28, 2009 No, there isnt a heat shield under there. Unlike the EFI and the SU manifolds, there are no cast in bosses that allow for a factory fitment of one. Doesn't mean one can't be made for it though! I do have some aluminium sheeting here, how thick would you suggest? Yes, I know of those 'heat guns', and looked them up on ebay...not too expensive but not something I would necessarily use often enough to buy...I dunno, it could become useful....I'm coming over to your neck of the woods soon and I'll be curious as to how well they work! I've been nutting this one out and I'm reasonably convinced that the factory water heater plenum is working too well. I'm either going to disconnect it completely or put a valve in there that can reduce the flow/volume. I have another idea but I will see how all this works first. I would really like to see more ignition timing than what I have now, if only to recover some of that lost top end power. Thanks mate. Cheers. Quote Link to comment Share on other sites More sharing options...
kolonelklink87 Posted September 29, 2009 Share Posted September 29, 2009 I dont think it has to be terribly thick - I certainly not an expert but it seems to be effective in stoppping the radiating heat in a couple of ways - works as a physical barrier for air rising off the exaust. - Reflects infra red (i've heard this but im extremely dubious as to the amount of energy thats actually passed this way) - absorbs heat from one side and redistributes by emmiting heat from both sides (probably closer to the "reflecting heat" effect) I imagine if you painted the manifold side with a low heat conductance surface primer or accryllic powder coat etc etc you might get an even greater heat transmission back towards the exaust and away from the manifold. maybe you could keep the manifold virgin by connecting a sheild via the common exaust/intake manifold head studs? I don't know if that would work with extractors but probs with the stock sheild.... heck you could probs use the stock zx efi sheild, i have one lying around somewhere...? I'd agree the stock water heater is probably the place to start... if you dont want to lose it you could put a restrictor upstream to minimise hot water flow... if the line ran across from pre-thermostat to post thermostat I image a highly resticted line would only flow significantly when thermostat is closed... ...or i could be completely wrong:mrgreen: Quote Link to comment Share on other sites More sharing options...
ozconnection Posted October 4, 2009 Author Share Posted October 4, 2009 I've done some work and came up with the idea to use a 'tap' or water cock/valve to stop or regulate the flow of coolant through the intake manifold. I could've bypassed the manifold completely, with no coolant running through the manifold at all. However, I wanted the option to use the heated manifold for warmup during the cooler winter months (A problem with previous setups when I didn't hook up the coolant through the intake). Today I started my engine and let it warm up to the point of thermostat opening. I was able to touch the base of the manifold with my hand without it being really hot like the radiator and radiator hoses. This was with the valve shut. When I opened the valve to let the coolant flow, the temperature of the manifold increased quickly to match the temp. of the rest of the cooling system. I could get tricky here, and setup some kind of thermostat arrangement, coolant through the manifold to speed warmup, then shut when engine is warmed up sufficiently. That might be overcomplicating things...maybe? The potential problem I can see with this is to accidentally leave the water valve open and advance the timing to where the engine makes best power. Ping city! Hmmmm, how to have the best of both worlds........ automatically? Ideas? When I get the chance for better weather, I'll take my machine for a run and play around with the ignition timing. The E32 was only 3km/h slower on the 400 meter run (G Tech) compared to the Arizona manifold when last tested, and that's with 10 degrees less static timing. I can't wait! Quote Link to comment Share on other sites More sharing options...
kolonelklink87 Posted October 4, 2009 Share Posted October 4, 2009 Hmmmm, how to have the best of both worlds........ automatically? Ideas? Maybe use a thermo relay (like with electric fans) post thermostat... connected to a solenoid actuated valve closing mechanism... ? or go the opposite way and have a spring loaded closed valve which is opened by a solenoid that can be tiggered by an in-car switch? like an *electric choke* lol or get tricky mechanically and use positive cooling system pressure(like in the radiator when it warms up) to close the valve? Quote Link to comment Share on other sites More sharing options...
h4nsm0l3m4n Posted October 4, 2009 Share Posted October 4, 2009 That's a pretty neat idea, I've been considering doing something on my 4 bbl setup. They make solenoid valves, which turn flow on and off with a switch. Here is one such valve: http://www.summitracing.com/parts/MOR-23905/?image=large You can keep manual control of the valve with a switch or use some kind of automatic control via a thermostatic switch. Here are just a couple ideas: http://www.summitracing.com/parts/MOR-63760/?image=large http://www.summitracing.com/parts/HDA-3653/?image=large These parts are all a little on the expensive side. I'm sure you can find cheaper, more generic, alternatives. Post pics of what you end up doing! I'll be very interested to see Quote Link to comment Share on other sites More sharing options...
ozconnection Posted October 5, 2009 Author Share Posted October 5, 2009 That's a pretty neat idea, I've been considering doing something on my 4 bbl setup. They make solenoid valves, which turn flow on and off with a switch. Here is one such valve: http://www.summitracing.com/parts/MOR-23905/?image=large You can keep manual control of the valve with a switch or use some kind of automatic control via a thermostatic switch. Here are just a couple ideas: http://www.summitracing.com/parts/MOR-63760/?image=large http://www.summitracing.com/parts/HDA-3653/?image=large These parts are all a little on the expensive side. I'm sure you can find cheaper, more generic, alternatives. Post pics of what you end up doing! I'll be very interested to see Thanks for the links Stepan! Food for thought from the Klinkman too!! Cheers guys. I'll be looking locally for switches. The prices aren't too bad from summit, but the postage and packaging costs they charge are outa control. Pool and spa centres have switches that are suitable for this sort of thing from what I can remember reading in Autospeed. I'll go there and hunt around. I'll let you know how I get on. Thanks. Quote Link to comment Share on other sites More sharing options...
scampbell0093 Posted October 5, 2009 Share Posted October 5, 2009 1987 300ZX 5sp non turbo.id like some info from you guys....wanting to put an 02 xterra VG33ER supercharger on my motor,without any change to the electronics in my vehicle...its completely stock no modifications except to move the airbox to the bottom of the chin..whats the differences in cams,crank, timing, heads and assemblies.also whats the difference in the supercharger from a standard and automatic????the one i have is from an auto but i own a five speed,,not interested in changing that....can i just bolt the thing on and change a couple of plugs???hurtin for info here guys....people at nissan just looked at me like i was nuts....my eventual plan is a lotmore complicated but this is the thing i have to start with.....thanks Quote Link to comment Share on other sites More sharing options...
kolonelklink87 Posted October 5, 2009 Share Posted October 5, 2009 1987 300ZX 5sp non turbo.id like some info from you guys....wanting to put an 02 xterra VG33ER supercharger on my motor,without any change to the electronics in my vehicle... Before you get to carried away with the details to put the response simply it can't be done so far as i know. L28E ECU will not compensated adeqautely for extra air flow nor are the injectors and other fueling components up to the task. It's definately not a bolt on option without extensive Fabrication work. There are two possible outcome if you can connect it up. 1. engine wont run at all. 2. Engine runs super lean and detonates massively as soon as you run it hard - destroying all your hard work. This is not the appropriate place to ask these questions, do some reading around, check the FAQ sections, run some searches... odds are someone has done something similar to what you want to do and has posted thier procedure. welcome to hybridz. -pete Quote Link to comment Share on other sites More sharing options...
kolonelklink87 Posted October 5, 2009 Share Posted October 5, 2009 (edited) -- scrapt that he said 300zx... wrong engine, wrong section... just... wrong *sigh* Edited October 5, 2009 by kolonelklink87 tag post for deletion Quote Link to comment Share on other sites More sharing options...
ozconnection Posted October 5, 2009 Author Share Posted October 5, 2009 -- scrapt that he said 300zx... wrong engine, wrong section... just... wrong *sigh* Yes, I'll agree with that!!! Quote Link to comment Share on other sites More sharing options...
ozconnection Posted October 9, 2009 Author Share Posted October 9, 2009 Took the car for a spin this morning and had the opportunity to put the foot down near some industrial estates. I had the water valve turned off so that coolant wasn't flowing through the manifold. Pulled the car over and opened the bonnet to see how hot the intake manifold was.....it was cool to the touch!! The runners were cool, the base of the manifold wasn't hot, luke warm is a better description. None of what I'm saying is particularly scientific ie no actual temperatures recorded, but take it from me, I was a little surprised at how cool the manifold was after a belting! And the ignition timing hasn't been altered yet, still on 7 degrees static! The power felt really good. With the water valve open, I had all sorts of problems with pinging and power reduction because of the heat factor, at least 50 degrees celcius difference if I can say that, temperature variance between ambient and coolant temperatures. It's all to do with thermal management. The water valve idea brought my attention to this idea and the advantages of a cool manifold for power, but a warm/hot one for startup and emissions etc. The automatic valve arrangement is still something that I'm looking into, especially useful in the cooler winter months. We're moving into warmer weather now, so there isn't any urgency ATM. Still, I'll keep you posted. I will try and test the car with the G Tech soon and post the results. Cheers. Quote Link to comment Share on other sites More sharing options...
ozconnection Posted October 10, 2009 Author Share Posted October 10, 2009 Hmmmm, one of the duties that I have for my Datsun is towing. Yesterday, I hitched up the trailer and drove up the freeway with the Klinkman to pick up a cheap L24E I bought off ebay. Quite frankly, the performance of my L28 with the E32 manifold was very ordinary! No torque at low rpm's and pinging.....not all the time, but after climbing a hill and pressing the throttle a little closer to the floor would do it. Damn!! But why? Something is happening here, but do you think I can put my finger on it? Buggar! It's frustating man. I can't believe that the Nissan engineers all those years ago didn't try to build a manifold for their L20's that would work.....on L20's. When grafted onto a stock L28, I wouldn't have expected the results I'm getting. Sure, a top end monster it might not be, but I would've expected the high gas velocity through the whole manifold would have provided lots of torque. I can't feel it, maybe it's because the timing is so retarded? So many 'maybe's' and 'what if's?'. What else can I do? Cam timing? I could retard it since its fully advanced at the moment but I'm somewhat reluctant since I'm moving away from where I want my power/torque to be. I'm not saying I won't try it, but I'm guessing now....and searching for solutions in the dark. Any suggestions? I'm wondering if I have a fundamental component mismatch issue here. The solution would be to take it off and reinstal the trusty Arizona manifold. It's getting close! Cheers. Quote Link to comment Share on other sites More sharing options...
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