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What are your guys' thoughts on a V8 in a 521?


71datsuns

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Are the l16 numbers forreal?im scared of even touching 5000rpms in mine but i do cruise it at 70-75 all the time.

 

A stock L16 can spin 6500-6800 easy. Add a matchbox dizzy and it can spin 7000 for short bursts. I wouldn't run it for a looong time over 5500rpm, but that's me. They run phenomenal at 4500-5000. Mine seemed to like 75-80 a lot better than 65-70. Zinged it up to 6200-6300 to pass people all the time.

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A stock L16 can spin 6500-6800 easy. Add a matchbox dizzy and it can spin 7000 for short bursts. I wouldn't run it for a looong time over 5500rpm, but that's me. They run phenomenal at 4500-5000. Mine seemed to like 75-80 a lot better than 65-70. Zinged it up to 6200-6300 to pass people all the time.

dam sounds nice. The most recent time i pushed mine to 90 for shits n giggles to see if it would make it i got a tiny hummm from my diff :-/

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Wow, thanks for all the replies and the insight. The thing is I drive 14 miles to work, I know to some that's nothing, I UNDERSTAND that there are people who drive a lot farther in these, but its all freeway and roads that are 50+, so I'm driving it at high RPM for about 20 min straight, and I'll tell you what, I'm going through a tank of gas in about 5 days time, I'm spending about 63$ every two weeks in this thing. That sucks. I was thinking L20b with a 5 speed too. That'll let me cruse at 55 - 60 at a nice low RPM. Anyone know a good engine shop I could take this L16 to and get it bored? And does the dogleg 5 speed bolt straight up to the L16? That would be a cheaper option if that's possible. I figured I could build the crap out of the L16 too. If I could find parts.

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If my math is correct, you drive about 140 miles a week to work. A Datsun 520 holds a little over 10 gallons of gas. If you put in 7 gallons of gas each week, you are only getting about 20 miles to the gallon. Not really good for a 521.

Check the compression. Do a tune up. Check valve clearance.

An L-16 has a torque peak around 3600 to 4000 RPM. It likes to run about that RPM.

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If my math is correct, you drive about 140 miles a week to work. A Datsun 520 holds a little over 10 gallons of gas. If you put in 7 gallons of gas each week, you are only getting about 20 miles to the gallon. Not really good for a 521.

Check the compression. Do a tune up. Check valve clearance.

An L-16 has a torque peak around 3600 to 4000 RPM. It likes to run about that RPM.

 

i love how you guys say ONLY 20 mpg :rofl: lol

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i love how you guys say ONLY 20 mpg :rofl: lol

 

You should be getting at least 25% better mileage than that... specially on the highway.

Check timing is 12 degrees BTDC. Retarded timing just throws gas away.

Check valve lash.

Check fuel level is correct on carb sight glass when idling. Too high may be flooding.

Check choke is fully off when engine is warm.

Lift each tire and spin by hand looking for a draging brake.

Proper air pressure. Low pressure increases rolling resistance and lowers gas mileage. It also heats the rires and will destroy them over time. Higher is safer than lower but look at the sidewall recomended ratings. Low tire pressure is the biggest waste of gas.

 

Tips...

Avoid full throttle to accelerate. Squeeze the throttle

 

Anticipate slow downs ahead and let off gas slowly to reduce speed. Leave extra room between you and the guy in front. What you are trying to achieve here is to use your brakes as little as possible. Just think... every time you apply your brakes you are throwing away the gas used to accelerate the mass of you and your truck up to speed.

 

Leave 10 min. earlier so you don't feel rushed. Learn to take your time. No one said it was a race to get where you are going. Relax, enjoy the view.

 

Empty out the truck box. Every pound you accelerate is gas used.

 

Inspect fuel system for leaks.

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"i love how you guys say ONLY 20 mpg :rofl: lol"

On the freeway, with careful driving, my 1996 Ford Aerostar will get 21 to 22 MPG.

4.0 L engine, 3.73 rear axle, with similar diameter tires to a Datsun 521. Sure, the Aerostar has a modern fuel injected engine, but it also probably weighs about twice as much, and has a lot more frontal area. It also has air conditioning, power steering, and an automatic transmission.

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Shitttt, I rarely have ever gotten over 20mpg on the hiway, never with an L16, as I was always floored trying to keep it going the speed limit on the hiway, and I know it was adjusted correctly, or at least close, because it passed emissions.

Once the L20b was installed I was able to achieve 19mpg hiway(70mph), but my co-driver got 23mpg once on the hiway(60mph).

The LZ23 was better yet, I got about 23mpg hiway breaking in the engine, but it was totally empty, and the speed was not constant, as I was breaking it in.

The more power I have, the better mileage I get, as my foot isn't in it all the time.

I have always had a 5 speed, as it had one when I bought it(dogleg).

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My L16 in my wagon got way better mileage at 55mph than 65mph, but then again I didnt care, and drove 65-70, or whatever the fast lane was doing.

 

I managed to get nearly 29mpg on my L19 with weber, driving at average 70mph on that tank.

 

My friends 521 has so much less power than my goon did when it had a L16. And he had the same rear end gears as I.

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Its your truck man, build it how you want.....just be sure to finish it. We hate to see hacked up Datsuns sold to scrap cuz someone couldn't finish a job.
 

 

Amen buddy! (L16, 210 semi-closed chamber head w/u20 cam (its a stock cam) (upgrading to a fresh rebuilt U67 head and a stock u20cam), switched over the old point style distributor to a electronic distributor, and presently running a weber 32/36 carb (but switching to remanufactured, and polished twin Hitachi SU's, with a Datsun 2000 roadster air cleaner), and a header, its got over sized exhaust, and magna-flo muffler) comfortable 60mph @ 3800rpm with balls to go faster and at 70mph @4300rpm....at 70 im still pulling off on level ground 8lbs of vacume (at idle im at a steady 20lbs of vaccume) with a stock 4spd transmission and rearend... BTW looking for a 219 head... fuel economy is impressive as long as you keep it tuned, best air fuel mixture, timing and valve adjustment.

 

shheeesh, when i got it i could only do 50mph, peeeing antifreeze all over the place, and vibrated like ....a...

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Im a newby to this, how do you post pictures on here?

 

 

^^ photobucket account, copy and paste, if ur computer is annoying it will give you issues like mine is right now

 

make sure you copy and paste the IMG code.

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