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I'm considering buying a stock 72 240z, and am wondering what I would need to do to make it run about a 14-15 quarter time. I am wary of the v8 conversion because I would still like to keep the weigth down for handling, and it seems like it would be a hassle. I am not well versed in the datsun engines and would like to find a source for info(website?) that could outline how to build a nice engine. Could I use the stock block? Also, an estimated price would be nice for each suggestion. I would probably be content with a little over 200 ponies, but I welcome all suggestions. Does anyplace build these engines for you? thanks
 

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just put a header on it and tune it real well you can get low 15's w/ that mostlikely

then you could alway go triple webers...but i dont know much about carbs....so ill let others sugesst
 

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Re: links

click over to "links" listed under miscellaneous on the left hand side...click under "informational sites...the "Datsun Garage" is my favorite however, there are many other great sites listed here, perhaps one that will suit your taste, good luck---Jerry
 

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MAKING 200 PONIES IS NOT HARD WITH A HIGH COMPRESSION 280 MOTOR THAT BREATHES WELL. YOU WANT A 280 FLAT TOP BLOCK WITH A E88 OR E31 HEAD USING PRE 74 SU CARBS OR TRIPPLE WEBBER CARBS ON SU STYLE 260Z INTAKES WITH HEADERS AND A FREE FLOWING WXHAUST WITH GOOD IGNITION OFF A 280 OR 280ZX AND MOST IMPORTANTLY AN AGGRESSIVE CAM. i WOULD RECOMEND A 280 DURATION 480 LIFT CAM, OR BETTER. A MOTOR OF THIS SORT THAT IS WELL BUILT SHOULD GET YOU INTO THE HIGH 13'S, DEPENDING ON DRIVER. jUST ASK NORM (THE 12 SEC GUY) HOW TO GET A 240 TO MELT SOME TIRES)
STILL 240
 

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Easy!

Since your only looking for 14-15 I'll shoot for the low 14 since thats really not that fast by todays standards. With a 240 you should look for a LSD (limited slip diff) from a 300ZX turbo, search the archives for a picture and year info. The ratio will be 3.7 which works well on the street if you want to wind up quicker get the 3.9 rear from an 81-83ZX 5spd. Find a 5 spd gearbox I like the later models ie 82 with a taller first gear then 1-4 are close ratio with a tall overdrive. I like the tall first cause I can pull into traffic, hit it in first and I'm going 40mph in about 2 seconds. Or go with an older 5 spd with wider ratios and a shorter 5th. Either way you will like and need the 5th gear. With the revised gearing you will accelerate alot faster.

For the engine, look for an F54 block 81-83ZX use the stock flat top pistons. Heres where it gets tricky, head choices. Quite honestly the heads are all different and some are much better than others out of the box, but after a good head builder has been over them they all can yield very similiar results. P79 is a good head and very plentiful usually come on the f54 block too. The P90 head is a good choice if you can work it, it will need to be shaved to bring up the compression then the cam towers have to be shimmed and the rocker arm geometry corrected - but this head has the best breathing potential as it was designed for the turbo. I run an E88 that is worked to the point of if it warps I'll have to replace it, since it can't be shaved any more. Both the E88 and E31 are great heads but both need larger valves and port/bowl work. The N47 or 42 is popular but I haven't used them. For more head info check the links that Z racer listed. A stock exhaust manifold mated to a 2.5" pipe with a dynomax, flowmaster, borla or supertrapp muffler is all the exhaust you'd need. If the stock manifold is warped, many are just get a header. You may not see much if any more power but you won't lose any either and the more head work you do the more power you will see. You will need a decent cam. I really can't suggest specs for a cam without knowing what you plan on doing to the head, rpm range you want and the intake setup. Its all a system and works together.

Intake either SU's or a tripple setup since your looking at a 240, the stock fuel injection could support the power and times your asking about though and might be more maintenance free. I tune my webers once a month, usually just need a slight balance adjustment which doesn't take long but is something to consider.

You will need an electronic ignition, the 240 has points which will be a pain on any type of performance setup. You can modify the 240 distributor or just use a newer electronic unit from a 78 Z or even newer 81-83ZX but you will need the brain as well or have to go aftermarket.

Really for the times your wanting the best thing would be to find a donor 81-83 ZX and swap the entire drivetrain with a few tweeks here an there, a cold air intake, open exhaust and gears you will be in the 15's easy.

Matt
 

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Re: Easy!

Tell me more about cold air intakes, I'm running a stock 240 air filter. Where would I find more info on cold air intakes??
 

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Cold air intakes

Dragonhead, I could be wrong, but I think Matt was referring to a fuel injection set up. You could rig up a way to get colder air to your carbs, but I don't think there is an actual unit you can use -- you'd have to fabricate something.

A lot of people say that the stock air cleaner is just fine. If you want to improve your situation, though, you might consider getting a "stock" K&N high performance filter. They cost 3 or 4 times the price of a regular filter -- but they last virtually forever. Or you could dress up your engine bay with dual K&N or similar complete air filter units. That will run you $75 or more.
 

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Re: Cold air intakes

I should have elaborated, you can make a cold air setup for your carbs several ways but all of them require fabrication. You can make a sheet metal air box that takes the place of your air cleaners and duct it to the front or you can duct it to the firewall and wiper motor access panel then you have to turn the area around the wiper motor into an air scoop. The wiper motor area is great for high pressure cool air as Tony D has been saying (do a search on Tony D or cowl induction) and is much more involved but like anything else you get out what you put in. Moving the filter to the front of the radiator helps but not all that much.

What I did for now is make heat shields that basically isolate my header from the intake & brakes. I used aluminum sheet, after making some templates from cardboard for the basic shapes. This alone made the difference in boiling the gas in my carbs and not. Also after driving for any period of time I can touch, hold, tune, etc any part of my carbs because they are just warm, they used to be so hot after 30 minutes of driving you couldn't touch them much less work on them. My car also runs more consistent without the heat soak I don't have that it runs real strong when its cold but after heating up it feels weaker syndrome.

Matt
 

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Recommend you go to the following site zhome.com and read the stuff on 3.0l and such there are some good ways to do it . If you going to blow some money though I think the V-8 route is the best for HP boost.
 
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