Gollum

Don't make assumptions!!! That's the #1 way to ruin something, wether it be building a motor or having a fun night out with friends. Check the block code. Pull a spark plug and get a flashlight shining in there to check for piston dish. KNOW what you have FIRST, then move on from there. Check ECU, does it have the NA pinout, or the turbo pinout? What color are the injectors? P90's don't just magically fall from the sky to land on NA engines. That motor was put together by someone, which means it's now your wonderful job to find out exactly what they did or didn't do.

If the low miles are accurate, then it might not be out of range at all. If it were a 150k motor I'd be curious as to the high results on a cold motor, but not a reason to be concerned about. Test variances are more important than actual numbers in my opinion anyways. I'd be happy with anything between 120-160, but a variance of more than 10% between cylinders would have me searching. Check valve clearance if that checks out, perform a leak down. Then if it seems like there's a leak do the oil squirt test (compression test, add oil into cylinder, check again, compare).

That's a very good question... I just bought a new digital caliper. I have a P90 and P79 sitting in my two Z cars. Maybe I should take off some valve covers and check it out for ya? Soonest I could get to it would be.... friday I think.

I agree, stock L28ET combo is your best bet to get this done. Don't worry about X head or X block. Stock turbo longblock will take 350hp all day long as long as the EFI is working right. All that said though, there haven't been THAT many cases of P79 liners breaking, several people on this board have run them just fine. Taking them out isn't that big of a deal though. There haven't actually been many people at all reporting detonation issues on flat top motors who are actually running a good EFI setup. The guys running high PSI are usually running dish pistons because it IS the most logical way to get to 400hp as beyond. To 300hp, either is a fine option and has been done. I honestly don't know where so many people are getting all this blown out of proportion information. Most of the actual blown motors I've encountered involved some VERY bad ingredients into the pot. Examples would be people trying to use a NA ECU, or a NA dizzy, or the crappy '81 system, or using NA injectors, or never even doing some basic tuning via fuel pressure regulation. People trying to increase boost and/or other mods without doing supporting EFI mods will ALWAYS be at risk to blow something up, no matter WHAT the compression is. If my '82 L28ET with 7.4:1 compression can run on CA 87 octane, I'm pretty darn convinced that it'd run 8.3:1 on CA 91 just fine. Now, I WOULD have to back the timing out a little, as the flame travel distance and time just got reduced dramatically with the increased quench. But what this says it that my required timing is less, but many people assume this means that the detonation threshold is lower. Also don't forget that at higher than stock boost levels more timing needs to be pulled as required timing is reduced yet again. Running any more than 10psi is asking for trouble on a stock turbo ECU, and running more than 1 psi is asking for trouble on a NA ECU. In all this though, to run non-stock setups a programmable ECU is a must in my opinion, and as such it IS NOT a budget option. I just wish people would quit throwing out blanket statements without showing proof that I have yet to actually see. One of these days I'm going to build a 10+:1 motor and make 400hp on it just to show it can be done. Might be a while but I WILL do it. And I'll have scientific results, such as dyno plots and logs to show power differences at various timing levels.

Yes, just not on an '81 block. In that year there were some other differences, mostly in the EFI setup.

+1,000,000 No reason to over think this. Just get a running longblock and throw it in. Shouldn't cost more than $500imo

If you're trying to keep a low budget on it, then it sounds like you know what to do. Run what you have, the cam + P90 + carbs. It wouldn't cost much to do the typical .080 P90 shave and install the shorter valves, but it can be very time consuming, or pricey for the gain if you're having a shop do 100% of the work. But will it run fine with what you have? Yes. How much power will it make? Depends way more on a million things other than compression. Yes compression matters a great deal, but chamber prep, port work, intake arrangement, carb tune, etc all matter just as much in the grand scheme of things. If you need a number though, I'd say 175whp is totally achievable by most people with that head, cam, and compression combo if everything else is done well. Some might get more, but many others get less, simply because they overlook details and just throw money into their project instead of research and patience.

Nope, this is all entirely impossible. Can't be done. The best thing to do is to just leave it stock... ... Okay, now for the real answer. All L heads will fit ALL L blocks (providing they're I4 head and block or I6 head and block). The setup might not be "ideal" but they all bolt up just fine. So yes, the P90A head will fit just fine and operate same as any other P90 head. The hydraulic lifters can definitely go beyond 5500rpm and should NOT be producing less power than the solid lifter heads. Problems arise when lifters go bad and start sucking power from your motor. Replacement lifters ARE difficult to find, but I've seen multiple motors with original hydraulic lifters running just fine to this day. Use whatever you can find or have. Fallow the path of least resistance. I know for me, lifter noise is the least of my concerns with my motor, but if I had super quiet exhaust and such maybe that'd be on the table for consideration.

Please do keep posting, for as much as you're stirring the pot I think it's good to do so every so often. Gets us all off our feet and DOING something, not just bench racing. Some of our very discussions on here have lead to some of the most interesting resources on the net (in my humble opinion). For example, we've really set a stake in the ground around here regarding engine weight. While most forums just let whatever fly, we take pride in putting out FACTS. Guys get high quality scales and give REAL WORLD weight figures, not some "X motor weighs X much" without details. Usually pictures are involved as added proof to show what was included and that nobody's fudging numbers. We've come to expect a VERY high standard around here. And if your engines really do live up to this hype, then you'll be in good company. Unfortunately our level of expectancy also comes into play regarding grammar. It's not that we're all high and mighty, we just want people to be understood around here. We have many people on these forums who speak english as a second, or even third language that have better grammar and typing skills than most high school students here in the USA. And they get their thoughts known and considered much more than the average high school student for all that hard work. Just a period and a comma here and there to make sense of what you're trying to say can make all the difference. You build amazing engines, where every detail matters. What if you thought it was just "whatever" when it came to making sure you had a perfectly clean engine before assembly? Just a little bit of that effort is usually what the moderators are looking for around here. I'll admit I've been having a hard time understanding some of your points, and hopefully that will change. But don't give up just because we're a bit harsh around here. We all have a bit of thick skin, and you're doing your best to test ours so I ask that you bear with us as we bear with you.

Electromotive had some good solutions to the very problems you mentioned, some of which has been discussed on this very site. We're not as much a bunch of shade tree mechanics as you might think. Temps will ALWAYS be an issue at 300hp per liter, but teams like electromotive proved it could be done on the L motor. I think we're actually in a much better situation today as 1. we're not bound to some of the limitations they had in their rulebook, and 2. EMS and turbo systems have vastly improved since then regarding what the consumer level person can get a hold of. I admire the determination on getting that RB26 head to work, and can't wait to see it in action.

I don't think any of us are asking you to be quiet, as we ALL would love to see that L3XDE(t) run! (including tony i bet) I think what we're getting to is that you've come on here and within 30 posts are trying to discount one of the best L engine builders in history who has plenty of records to prove their importance. As to making 133hp per liter, I don't think that's other/worldly at all. And a 2 valve engine isn't as inherently air flow limited as people seem to suggest. And regarding the NASCAR comparison, remember that they could make MUCH more power if they weren't limited to some of their rules. Although they're almost as technically advanced as F1 motors in some ways, their long stroke will always be a limiting factor for all out HP figures. You can see this in the trend of MotoGP over the years. Bore sizes in a cc class has increased and increased over the years while volumetric efficiency hasn't improved dramatically. F1 has a similar story, where VE hasn't changed more than 10-15% in the last 40 years, yet HP per liter has increase DRAMATICALLY. Just some food for thought.

Crank or wheel 340kw? If those weights are accurate (don't forget to add your weight, I've made that mistake), then you had roughly 414hp at the wheels on that day in those circumstances, which I feel roughly does match the claim of 340kw if that's flywheel, as that's 462HP. Now, if that's a NA L motor my hat is off indeed, and I'd certain want as much info as you're willing to provide. Is that the case? Was this a NA L motor?

Sounds to me like your robello isn't a full race head, but rather a hot street port... Tony's claims on the robello in the Bonneville car aren't bogus, and can easily be looked up in the records. His point comes down to a very pure truth. That motor was making a DAMN LOT OF POWER. There's no way it was flowing a measly 230cfm. That's CFM that many here have achieved in their garage! So the moral of the story is that you can't base all of robello's work off of one head. Did you order the head yourself? Do you have the invoice list that shows the work done and the guarenteed HP claims? And a horsepower is a horsepower is a horsepower. Yes measurements vary across the world, but 1 HP will always = 745.699 watts. An example of measurement differences though is how the L motor went from SAE gross to SAE net in the late 70's and magically lost 30 or so HP, which is a big hit when under 200hp anyways. Some people claimed that smog devices were robbing HP, but that was complete bull. The rating system changed, period. Today's research shows that the P79 and P90 are some of the best flowing heads, and that the smog devices if working properly (which they would have been in '79) won't rob considerable HP. What changed was a rating system, that's all. But that's where MOST dyno's show some truth through the haze (though I personally feel that real world performance such as trap speeds or Bonneville figures are even more truthful). A water brake dyno can give us raw HP figures of what an engine is actually doing. Unfortunately things like dyno calibration, dyno type, dyno room temps, etc can all play huge roles in the figures. I've seen the real world proof that you can take an engine can vary the HP on the dyno by as much as 20% without changing a single part on the car, or re-calibrating the dyno. Then you've got dyno calibration error and dyno type variances thrown into the mix... ...which is why a 1/4 mile trap speed with known running weight is hard data to ignore. It's as "real world" HP as you get. So do you have any 1/4 slips with weight figures?

Can you add some punctuation next time to make that a little easier to read? Thanks! Now, what is it about OZ that makes engines dyno low? Are you at 10,000 feet elevation? Or is it from insane temperatures? Because I'm pretty sure both of those aspects we have to deal with here in the states. We have people making crazy HP in Arizona, and up in the mountains as well. Or are you using dynos that just read low? Because some of the high HP L motors here in the states are on heart-breaking dynos too... Also, I've never heard of Robello advertising their motors as 400hp. I don't doubt they can do it, but the garden variety $10k motor stroker that comes out of there is usually guaranteed to 300hp, not 400... And tony wasn't referencing a NA motor.... I don't see where you got that impression...

You know, after my last post I decided to go back and do some homework and voila! Very right you are sir. It was just too late in the evening and I didn't want to go back and make another post at the moment. You're definitely correct though, you could easily run 6 spark outs to COP as long as the coils have ignites built in, and have zero worry about overheating your MS. So, unless you don't want to buy 6 coils, go COP with MS!

Ummm..... less is more? Yay weight reduction! Honestly, our laws are the #1 reason one of my best friends got into subarus. They're the ultimate stealth smog car. AWD cars currently don't have to go on the rolling road, and due to their turbocharged nature there's lots of power to extract with very little visual change. AND you can tune the ECU with nothing but a fancy USB cable and open source software, which also allows you to removing all those fancy tip offs that the ECU would send the smog machine, making the electronic side a pass-every-time situation. Then just pass the EVAP and the sniffer, and visual and you're good. This is how there's STI's roaming the streets that put down 500+hp that still don't need special smog hookups, yet 200hp hondas fail daily. Is it legal? Heck no, but since when have car guys all been doing things the legal way? American graffiti anyone?

Because, if you're doing wasted as per suggested by the MS resources then running an inline 6 with 3 coil outputs for wasted spark operation on ether the V2.2 or V3.0 boards then they suggest wiring in a new connected, like a DB15, because the traces won't support the current draw. Maybe that's changed with some revisions that I'm unaware of, just going by what I've read. If I recall correctly they also suggest mounting the drivers you'll be using for the coil triggers one the topside of your case to remove it from the circuit board. EDIS simplifies it by having good, quality drivers right out of the box and a simpler configuration on the MS side. Yes it's more wires, but it's the "tried and true" method that more people take from what I've seen. I honestly wish more people would go with MS directly driving coils as we'd know the real world performance and limitations that brings the people doing the write ups to suggest these modifications as "required".

All very true, the EDIS setup is just plain easier though and removes some of the complexity. That's all. Those new trigger disks for the dizzy sure look interesting though! I'd be really interested to see some logs going up to 8k to see if there's any signal noise/scatter.

And how many driving S30s? Unrelated to that reply of mine, I find it hysterical what really drives the prices of the 240Z up. I got my rust bucket '75 and DROVE IT TO WORK THE SAME DAY, with a L28ET swap DONE, for a whopping $1,100... The rust isn't even BAD, my battery tray is still completely functional/salvageable. It had the typical rust at the bottom of the doors and fenders, and basic little sports here and there. All in all it's a fairly solid chassis, especially compared to some of the clunkers I've seen people pick up. Moral of the story? Stay away from those damn early S30 cars that all these zcar nuts seem to be obsessed with because they were the "pure" s30. I personally feel the chassis only got BETTER with age and have seen first hand that 90% of that extra piggish weight it gained through the years is fat you can CUT OFF! Somehow these purists missed this fact and instead just want a car they can buy and own which is the "right z car". What a load of bull. It's 11:43 right now, lets see how long it takes me to find a decent 260Z or 280Z on craigs nearby me... looks like a parking lot fix to me: http://sacramento.craigslist.org/ctd/2795804700.html This guy has a recent thread here, guess he's in over his head, steal it! http://sfbay.craigslist.org/eby/cto/2803410555.html need more info http://sfbay.craigslist.org/eby/cto/2778188212.html pretty clean, would have to see in person to look for serious rust, not a great deal to me otherwise http://sfbay.craigslist.org/sby/cto/2798949975.html more swap? BAM! http://sacramento.craigslist.org/cto/2801288243.html 2+2 joy! http://reno.craigslist.org/cto/2768885451.html oh boy, pre-smog test! http://chico.craigslist.org/cto/2746447098.html lame photo http://redding.craigslist.org/cto/2803680618.html might be good http://merced.craigslist.org/cto/2809550303.html There, it's now 11:48. It's been FIVE MINUTES..... I rest my case. The cheap project cars ARE out there, they're just not "series I, II, or III" what ever that bull is all about

Unlikely. I've gotten several of these engines running after years of down time. The worst case had two sticking injectors which freed up by the second tank of gas. Still started and drove on 4 cylinders though.

**and for the next guys search who refuses to click above links** rebuild head to stock (since it's bare) add stock turbo manifolds ms 1 or 2 + EDIS add fuel add boost voila!!! intercooler, BOV and other turbo supporting mods would be a no-brainer Shortest informative post of the month for me! w00t!!

Thank you for sharing that link! That guy is awesome for what he's doing. I've never seen anyone take RWD conversions so seriously and still keep it within reach of the average joe. Seems like most adaptions end up costing considerably more than double what he's asking.

I'd be more worried about getting an EFI manifold to flow well at high RPM than getting L24 carbs to work well on a L28. The stock EFI manifolds are horribly undersized and become a major choking point beyond 5000 rpm. Sorting out exhaust on the L28 is also easier than sorting out converting to EFI. Some basics you'll need to figure out: Fuel pump (usually $200 new for a good one) Fuel Return line (not expensive, but time consuming) Fuel Filter (another nickle and dime in the bucket) If you don't have them currently or the ones you have are iffy: Fuel injectors Fuel Rail Fuel pressure regulator (commonly out of spec) AFM (or other air metering sensors if you go MS) AFM mounting (since your car is a 240Z you don't have that bracket, one more thing to figure out) O2 sensor To sort out all these changes could take some time, definitely consider this when making your decision. It might seem confusing to figure out how to carb the L28, but trust me when I say that's a much smaller mountain than converting a carbed car to EFI. Both are totally doable and obviously anyone swapping a non-stock motor has considered these things and had to come up with solutions. Regarding the parts you have: You do indeed have flat tops if the motor is stock, and if you trust the E88 head there's no reason you couldn't use it. Your compression would be in the mid 9's, opposed to the mid/high 8's the P79 gives you. I'd suggest running a little bit more cam if you do that though. The P79 will take some minor work to get carbs working on, but plenty have done it. If you want to use the mechanical fuel pump on the E88 you'll need to do some basic machine work (doable with a basic grinder and a tap and die set). You could just use an electronic pump up at the engine though instead. So you have options, none of them being bad options if you do your homework and pay attention to the detail when it comes time to work on the car. I've seen 300hp carb'ed NA motors, and 300hp EFI NA motors. I'm personally among the crowd that prefers EFI, but at the same time I also believe in the path of least resistance in order to actually DRIVE your car, not let it live on jackstands.

If cost is any concern, just run the carbs. But macambra's advice is wonderful. Get it running with what you have, and then do research on EFI. MS-1 build at home + wideband can be done under $500 easy. Buying a prebuilt MS-2 3.57 board + relay board + wideband + sensors + throttle body and other general "while I'm at it" stuff can run up over $1k. By contrast though, most other ECU's START at $1k and you still have a lot of work to do... MS really is that awesome. MS cost also doesn't look that scary when you look at the cost of getting a really nice tripples setup with all new parts. But, you already have working carbs, which means you could be avoiding this cost all together. Regarding what head to use... well what motor is this L28, and what head is on the L24? The L28 could have flat or dished pistons which really affects any choice. You can throw carbs on an injected head, but most people recommend filling the injector cutouts on the intake port of the head, but it's really not a huge deal to just leave them there as a mild low pressure area. Unless you're shooting for 200+ hp who cares? Just putting your exact setup on a L28 longblock will give you a solid 15% increase in power once you get the carbs adjusted. And the beauty is that the torque increase should be seen everywhere, not just on top or on the bottom.

Totally awesome build! I think these swaps would be a bit more common if an affordable RWD conversion was pioneered. From everything I've seen you're looking and a mostly custom flywheel and adapter plate, and I haven't seen kits for mating to common trans like the 300zx or supra boxes. I'm looking forward to see where this goes though!