76s30 Posted March 24, 2007 Share Posted March 24, 2007 Let me take this opportunity to introduce my self. My name is Jake, I live in Green bay. One of the cars I currently own is a 76 fairlady Z I saved from a barn other than the lower core support its clean. it was originaly brittish racing green (looks about that color under the carpert) now its a blue that looks sorta like the 350z color. (painted before I found it) When I found it it had dead mice in the HAVC system, it was dirty and other than paint and maybe the mirrors (they are power, still on the fenders though) it was original. The fuel injection system was in/op faulty ecu I believe. The fuel lines leaked every where The clutch was in/op I replaced the clutch, removed the fuel injection system wraped and boxed it. installed triple 40mm phh mikuni's MSA "stage 3" cam, and the correct lash pads. MSA 6 into 1 header 2 1/2 " exhaust Magnaflow SS muffler Holley fuel pump inplace of stock hi pressure efi pump and a regulator. well under 3500 it ran like poop, due inpart that the carbs were set up for a 2.8 with same cam. rejetted it, and ran good.Took the car to the family afair for Thanks Giving, on the way home I put it in 2nd not 4th (doh) floated a valve. Now its almost Z driving season again here. If I'm rebuilding an engine its going to be a 2.8 N/A for now with room to turbo later. so my question to whom as ever been kind enough to read this far, is are 40mm phh to small with an N42 head stage 3 cam on a 2.8 I would like to make 170 -180 whp. I'm afaird that the 2.8 will run out of breath on the top end with 40mm carbs, are my suspisions true? Thank you Quote Link to comment Share on other sites More sharing options...
quicker240 Posted March 24, 2007 Share Posted March 24, 2007 The 40's will be enough for up to about double that.Sounds like a neat project.Good luck and post pics! Always like to see a Fairlady Z.BTW,you will likely be happier with the fuel injection.Any stock ECU will run it and they are not hard to come by.Get a factory shop manual and go through the troubleshooting step by step.You will have it running in no time,and it will be more drivable and reliable. Quote Link to comment Share on other sites More sharing options...
76s30 Posted March 24, 2007 Author Share Posted March 24, 2007 Quote Link to comment Share on other sites More sharing options...
savageskaterkid Posted March 24, 2007 Share Posted March 24, 2007 If you decide you would like to give Fuel injection a try, I will trade you my Megasquirt V2.3 with harness and cable, and my 550 injectors for your mikunis Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted March 25, 2007 Administrators Share Posted March 25, 2007 First off, Welcome to Hybrid Z. Nice looking Z you have there. Now when you installed the cam and lash pads, did you install the matching valve springs? If not, you are not realizing the full potential of that cam as the valves are floating below where that cam makes it power. If you are using the stock valve springs, as the engine revs, when it gets to say around 5500 RPM or so, you’ll notice the engine takes on a more aggressive harsh growling noise that gets louder the more it revs… that is valve float! That cam with the triples should be pulling hard up through 6500 RPM and the engine should rev to around 7000 RPM before it starts making that growl noise. 170-180 wheel HP is totally realistic for an L-28 with triple 40’s and a mild cam. A quality ignition system is a must though. As for the EFI, If you do go back to the OE EFI, you WILL need to put the stock cam back in as the OE EFI can not be tuned around aggressive cams. Even with mild cams, drivability in some area will be compromised if an aftermarket cam is used. If you use an aftermarket stand alone EFI, then you can use whatever cam you want as you can tune around it. Quote Link to comment Share on other sites More sharing options...
76s30 Posted March 25, 2007 Author Share Posted March 25, 2007 Thanks for the compliments guys I am new to L series, carbs, and Datsuns. Nissans (even though its the same thing) I'm familiar with, I've had my share of Z31's, sentra's, 240sx's I'm also currently working on my 76 celica liftback , new frame is almost done and bbf is going in soon Thanks again Quote Link to comment Share on other sites More sharing options...
Turbo6inKY Posted March 25, 2007 Share Posted March 25, 2007 I would like to make 170 -180 whp. I'm afaird that the 2.8 will run out of breath on the top end with 40mm carbs, are my suspisions true? Thank you I'm putting 175 to the wheels with a 2.7L (2.8L block bored .040 over with a 2.4L crank) on a high compression E31 head with the larger N42 valves, and I'm running the same 40mm Mikuni carbs you have. Right now, it pulls all the way to the rev limiter, which I have set at 7100. The curve wasn't dropping off much there. I've left it at 7100 for longevity, but it would easily pull all the way to 8. You will have no trouble making your target amount of power with those carburetors. Quote Link to comment Share on other sites More sharing options...
76s30 Posted March 25, 2007 Author Share Posted March 25, 2007 So then would it be worth it form me to rework my E30 head thats on the l20a right now with bigger valves and new springs, port polish, I've heard the E31 head takes alot to get it to work as good as a N42 or P90. Are the camber volumes the same on the E30 and E31 I thought that they made them smaller for the smaller engine. To BRAAP No I did not install the valve spings, it did pull hard to 6k (the stock redline) I rarely took it to 6500, so I guess I didn't make note of the exhaust note change, by valve float I meant the valve kissed piston and bent the valve. thank you for your insight. Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted March 25, 2007 Administrators Share Posted March 25, 2007 Piston to valve contact.. OUCH! I hate it when that happens. If you get the chance, I do recommend that you install the matching valve springs and that piston to valve contact issue “shouldn’t†happen on those accidental missed shifts.. I’m not saying that it wont happen, but the chances are much less as the correct valve springs will help keep the valve motion much closer to the cam lobe, especially for those unexpected missed shifts… Also, being as this is the sweetheart L-20A and with this cam and carb combo, that engine should easily be pulling through 7000 RPM. I’d gather that between 7250 and 7500 would be ideal shift points for maximum acceleration with your current setup, if the valve springs were matched to the cam that is. (ok, enough about the valve springs. ) If I remember correctly, the L-20A head has much smaller diameter ports therefore would require “extensive†port work, like way more port work than I’d ever want to perform on one head, (and that is if the port walls are thick enough to allow that much material removal). Depending on your specific plans for the L-28 build up, the N-42 head is a great HOT street head. We’ve built many N-42’s at various stages of mild to wild and are currently building 3 for customers in Europe, all three are running triples and moderate N/A race engines, and a 4th is a local customer with a one of a kind N-42 receiving more power enhancements. Keep us posted as you get it back up and running… Quote Link to comment Share on other sites More sharing options...
greenmonster80 Posted March 25, 2007 Share Posted March 25, 2007 Sweet car. Love the skyline tail lights, JDM bumpers and the early style front end. L20A motor will rev really well, but I ditched mine for the L28 as well. Nice find you definitely saved a keeper. Quote Link to comment Share on other sites More sharing options...
savageskaterkid Posted March 26, 2007 Share Posted March 26, 2007 willing to trade Quote Link to comment Share on other sites More sharing options...
76s30 Posted March 26, 2007 Author Share Posted March 26, 2007 the tail lights were acutaly a kit sold by a company called "IMPACT PARTS" they were based out of NYC that kit was sold in the late 80's early 90's I don't know how ever what vehicle they actually sourced the lights from, but they made the fiberglass rear filler panel. again they were installed when I found it and they are ultra rare and I kinda like um so there they stay. A little more info about the car, when i was going through it I found the original wheel stops still sealed in the plastic bags they came in. and some emission testing papers from 4/84, 10/85, 7/86, but they are in japenese, I'll try and snap some pics of um if you would like to see. There also a U.S. forces Japan sticker on the windshield just above the rear view mirror, assumably from the serviceman who owned it back in the day and was nice enough to bring it home with him. Sorry savageskaterkid unless your going to finish my 3 other projects for me no Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.