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COMP Cams MJ121-2 MaxJet 0.121" Orifice Precision Carburetor Gasoline Jets - Pack of 2

Part of: COMP Cams MaxJet Precision Carburetor Gasoline Jets

Other options in this family: COMP Cams MJ82-2 COMP Cams MJ122-2 COMP Cams MJ108-2 COMP Cams MJ58-2 COMP Cams MJ59-2

Manufacturer

Picture for manufacturer COMP Cams

Part Number

MJ121-2
10 reviews
Sale Price

$7.47

1 left at this price

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Usually delivered within 2 days

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Product Details

The COMP Cams MJ121-2 MaxJet Gasoline Jets are a precision-engineered solution for racers who demand accurate, repeatable fuel delivery from their carburetor. Traditional slot-type jets installed with flat blade screwdrivers are prone to slot damage during installation, which can alter fuel delivery by as much as 50 percent — making jet tuning an exercise in frustration. MaxJet eliminates this problem entirely.

These jets feature a 0.121" orifice diameter and are sold as a pair (quantity of 2), giving you matched jets for both primary and secondary metering circuits. Machined from durable 5/16" hex-stock brass, they are installed with a standard 5/16" nut driver — no screwdriver required, no slot damage, no inconsistent fuel flow.

Key Features:

  • 0.121" precision orifice for accurate fuel metering
  • Sold as a pair (2 jets) per package
  • 5/16" hex-head brass construction — installed with a nut driver, not a screwdriver
  • Eliminates slot damage that can skew fuel delivery by up to 50%
  • Direct crossover from equivalent Holley carburetor jets
  • Compatible with all known racing gasoline fuels
  • Virtually indestructible for long-term, repeated use
  • Smooth and precise fuel delivery for consistent tuning results

MaxJet carburetor jets are available in sizes from 0.050" to 0.120" for gasoline applications, in 0.001" increments, making it easy to dial in the exact fuel curve your engine demands. The COMP Cams MJ121-2 is the ideal choice for carbureted race engines running at the upper end of the gasoline jet size range.

Products specifications

Jet Drill Size (in)

0.121 in.

Jet Material

Brass

Jet Type

Alcohol

Notes

Produced with a 5/16 in. hex head.

Quantity

Sold as a pair.

Thread Size

1/4-32 in.

Carb Type

Holley

Jet Size

0.121

First of all, I can not believe how fast I recieved my order, 2 DAYS! Best of all, the instructions made it easy for a non mechanic like me to install.

They were Very quick and i was very happy with the service i got!! 9-10*

Best price I could find on the web even after paying for shipping! Shipped in a couple of days and great service!

The ordering process was very simple and the prices could not be beat. The processing time to ship the order was a little longer than usual, but for the price savings, it was well worth it!

Very nice website!

Ordered a CAI kit and Autoplicity had the lowest price. They're website didn't correctly match my vehicle to the product and it took a few days to ship. They're support was friendly and quick when I emailed them about the delay.

Great customer service, item shipped quickly. Very satisfied.

Great site. Provided needed technical specs. Shipped promptly. Although I had to ask for the tacking number, it was not emailed, one was provided promptly upon request.

I couldn't find these ARP studs anywhere else for this price! $20 less than ANYWHERE! Definitely coming back to shop at Autoplicity.

This is the easiest purchase I ever made. The visor is great and installation was a breeze. The service by Autoplicity was A-1. Shipping was better than standard. Will buy from them again.

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