1600 air filter modification

Tech tips and how to's

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SOUPY
Roadster Fanatic
Posts: 90
Joined: Sat Dec 26, 2020 7:21 pm
Location: Smith Mt. Lake Virginia
Model: 2000
Year: High Windshield-68-70

1600 air filter modification

Post by SOUPY »

Looking at my stock air filter backing plate, it seems like cutting of the two 90 degree elbows would help air flow? I have a slightly modified stroker engine. Has anyone done this and seen/felt improvement? Pro's, con's?
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Life's too short, buy your best tool first!
69 2000 'Lil Red, pretty much done
66 1600 Stroker, Whitelady, in progress
JT68
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Posts: 2921
Joined: Sun Jan 27, 2013 9:43 am
Location: Cumming, GA

Re: 1600 air filter modification

Post by JT68 »

The longer stacks improve torque. If you cut them off and replace with a stubby full radius stacks you MIGHT see a minor improvement in top end, loss in the lower end, but probably imperceivable without a precise engine dyno.

If it is a stroker, you should consider higher flow carbs AND filters. The 1600 setup is probably ok up to about 1800cc and ultimately becomes a limitation as the displacement increases.

If you are primarily interested in torque under 5k, what you have is perfect.
LT/JT
https://www.datsunrestorationproducts.com/
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SOUPY
Roadster Fanatic
Posts: 90
Joined: Sat Dec 26, 2020 7:21 pm
Location: Smith Mt. Lake Virginia
Model: 2000
Year: High Windshield-68-70

Re: 1600 air filter modification

Post by SOUPY »

Thanks JT! Mild stroker with your light weight flywheel. Looking for the low end torque. So on carbs, what would you suggest? Moving up to a Solex setup?
Life's too short, buy your best tool first!
69 2000 'Lil Red, pretty much done
66 1600 Stroker, Whitelady, in progress
JT68
Talented Enthusiast
Posts: 2921
Joined: Sun Jan 27, 2013 9:43 am
Location: Cumming, GA

Re: 1600 air filter modification

Post by JT68 »

Sweet, sounds like lots of potential :smt023

You could do Mik PHH or DCOE's, but the currently available manifold is junk unfortunately. Dave Premo can redrill the pierce manifold for you, however the linkage is still a PIA. Most expensive and time consuming, Otherwise an OK choice.

If you are good with SU's you can bolt on U20 SU's to your manifold which requires linkage changes and tons of tinkering with needles and mixture.
Conceivably, this works fine, in practice the results are usually less impressive unless you are SU master class samurai. Possibly the least expensive other than the time commitment.

My favorite for strokers these days are 42mm Mikuni HSR. So nice, very easy to understand and just about infinitely tune-able. Virtually no air flow restriction through the carbs-they are pretty much wide open- so top end&mid range is excellent. Also will bolt right on to your manifold with proper mount kit. Easy. These also require some details/tinkering to tune out, but definitely excellent in the long run. (most folks who run them will never go back to SU's)

Shoot us an email, we have components for all these options and can point you in the right direction if we can't help.

An onboard O2 sensor is a great aid even with the carbs you have, so you might add that first before changing anything else (unless you already have one) Cheers, have fun!
LT/JT
https://www.datsunrestorationproducts.com/
Only the very BEST parts for your Datsun- 10000's of items in stock
New, Used and Reproduction!
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