n-42 head

[cobraz240z]

I have been reading up on this head and it is my understanding, that if you put this head in a L24 l26 or l28 you will get a lot of compression. So i was wondering if I put this on a low milage L24 motor and port and polish a n42 head oversized valves headers and put my dellorto's and a hot cam how much hp will I make, and will it be streetable? i will run on 95 octane

[technicalninja]

These combinations regard stock combustion chamber CC N42

Early 240Z 70-mid 72 will lower compression

Mid 72-mid 80 compression will not change as this head has same CC as all heads applied to these years.

Mid 80-last 83 NA will raise comp to approx 10-1 (flat top pistons)

All turbo ZX will raise comp to approx 8.5-1. (dished pistons)

 

Put on an early 240 with the parts you described it will probably produce LESS power that stock set (yes-even with the SUs) up untill revs pass 6000 after which increased flow capabilities will come into play but lack of compression will still restrict total power output. It will make about the same power as the stock 240Z (maybe a little more) but it will have lower torque at all engine speeds below 6 grand. I would expect loss of .5 seconds in 1/4 mile ETs.

Yes it will run on any gas you can buy (even cheapest regular) and adding a big cam will only make these problems worse and the cam will be necessary for operation above 6 grand. It will also require a custom balancer and other hi rpm operation mods to increase reliability at these speeds. Just bolting this head on a stock bore 240 will require "eyebrowing" of the cylinders and putting bigger valves in the head may not clear cylinder walls even with extensive mods (valves will hit cylinder walls).

 

This set up you described will work pretty well on a flat top piston 280ZX engine and set up with a proper cam (not the biggest cam that is available) should produce power in the 200-240 range (depending on setup and the tuning abilities of the guy who does the work) and it will definitely work with 95 octane fuel and properly tuned it should work fine on super-unleaded pump gas.

I built a customer engine using N42 (ported and worked comb chambers)flat top N54 block/ tripple Webber, small preformance cam, big exhaust and the car now has almost 30,000 miles on engine with no mechanical problems. It will out accelerate a stock LS1 Camero and has gotten as good as 24 mpg. It has only been run on 92/93 pump gas and does not ping but each part was chosen to balance/match the other parts.

A better head for a 240Z application is either an E31 or the Maxima head of which much is written on this site.

IMHO more investigation is needed on your part. Any performance engine has to be built to a proper plan and the mods need to compliment each other.

[evildky]

just download the L series engine calculator and start playing, there is really no reason to keep the L24 when the L28's are soo readilly available, there is no replacement for displacement

 

 

 

and for any dorks that think a turbo is a replacement try turboing the larger displacement motor.....

[ww]

and for any dorks that think a turbo is a replacement try turboing the larger displacement motor.....

 

Tell it like it is preacher! 3.1L and turbo with 25psi... Ummm... A guy I know is about to turbo his high compression 3.2L Rebello. THAT's gonna be a kick in the azz!

 

Seriously, everything has to be designed as a system or you're more likely to hurt your total power potential or put it somewhere you'll never go for long, like 7000 rpm.

 

Figure out what you want to accomplish first, then you can start getting advice on what pieces will get you there and what mods you'll have to do to realize your goal.

 

Good luck!

[briann510]

Hey I think I might know that guy thats gonna turbo his 3.2 Rebello high compression engine!

 

We will be pushing 500+ hp with it with less that 12 psi

[cobraz240z]

ok if i port a e31 head and put the 3x2 and large exhoust and a good cam how much hp will i make? or what is a good combo that is economical and good power i laready heave the 3x2 dellorto 40's i still need to get the rest of the stuff should i use the e31 head or the n42 what do you guys recomend i allready

have the e31 any suggestions

[ww]

We'll try this again. What are you trying to accomplish? Do you want to hit a certain 1/4 mile time/speed? Do you want a fun street car to piss off some Honda wannabe? No comments from the peanut gallery Brian! Do you want a sweet cruiser?

 

We can't really tell you how much that setup will make because there are still too many variables. I suspect it will make somewhere between 90hp and 200hp to the wheels depending on who builds and tunes it, what cam profile is used. Saying you're going to use a 'good' cam is not helpful because a good cam for one application is a terrible cam for another.

 

Since the N42 would actually lower your compression ratio on an L24, I would stick with the E31 unless you want to go turbo and then the N42 would probably be a better choice.

[JMortensen]

If you built it up comparable to Brian's 3.2 liter, you could expect the following. Brian gets 278 whp out of 3.2 liters, or 86.875 hp/liter. Your 2.4 could expect 208.5 whp if similarly built. You're probably looking at $7K minimum to get the engine built to the point where you'd see that kind of hp, assuming you send the parts out and then assemble it yourself. Won't be nearly as expensive as Brian's because you don't need to source the stroker crank and rods and all that or weld up the combustion chambers like they did on his, just basically a forged piston bottom end with some good port and polish work on the head.

 

That's my best SWAG anyway. Do the same thing with a 2.8L and you're looking at ~250 whp FWIW.

[violacleff]

500hp with less than 12psi? That sounds kinda optimstic no? Everyone was bowing down to Hoover for making 404hp at 15psi, and he had a whole lot of one off parts, motec, and what not. I guess anything's possible. Good luck.

[katman]

ok if i port a e31 head and put the 3x2 and large exhoust and a good cam how much hp will i make? or what is a good combo that is economical and good power i laready heave the 3x2 dellorto 40's i still need to get the rest of the stuff should i use the e31 head or the n42 what do you guys recomend i allready

have the e31 any suggestions

 

You'll get more intelligent responses if you use caps and punctuation, dude.