chewy1234

Does anyone have any experience with a Weiand 8124 and 4100 carb with 1.08. I am converting my 65 289 to 4V. I have a cast iron intake, but am leaning on the side of not using it.

jcthorne

You are headed in the right direction. The 4100 carb with 1.08 bores is an excellent carb that will get 98% of the possible performance out of a 289 and do it with better drivability than any of the aftermarket products.

67mustang302

It'd be a good setup for a mild 289. If you're building bigger power than you might want a different carb with more tuning flexibility.

chewy1234

I will eventually do a rebuild but for the time being I want something reliable. Is the cast iron intake better than the weiand?

longlive289s

i just did the 4v swap. went with weiand action + manifold (which i think is the Weiand 8124) and a holly street avenger 570cfm carb (289 .010 over). freakin love it. very easy to tune and i was able to re-jet it in 10 mins.

im assuming the cast iron is the stock intake, correct? id get something lighter. i pulled my 2v intake and weighed it. somethin like 41lbs. the new aluminum one is 12lb. lol

not a hard swap at all and trust me u dont need to pull the distributor out like manual says

before


after

Starfury

You don't have to pull the distributor, but it makes life a lot easier. Getting a 41lb 2V intake out from behind a distributor would be a PITA.

Go for the 8124. It's worth it in weight savings alone, but it also benefits from a more modern runner design for better throttle response and higher rpm flow.

longlive289s

getting the intake out with the distributor wasnt that hard. break the seal the basically move the intake back then lift it up. seemed a lot easier than pulling the dizzy. simple



edit....go juventas lol

matt_lamb_160

longlive289s, what carb was on your Mustang before you did the swap?

What was the difference in installed height between the two setups (to the top of the carb)?

Starfury

Pulling the distributor takes 30 seconds. Timing it doesn't take much longer.

longlive289s

ya the weiand 8124 is good. i was bouncing back and forth between the edelbrock air gap but was told multiple times the action + was just as good if not better than the air gap.

old carb was the stock autolite 2100. ive heard the motorcraft 4100 is pretty freakin good but funny thing is....its about $50 more than the holley. depending on where you wanna go with your build.....the street avenger is good but you can get bigger numbers from a double pumper or a demon carb, but expect to start shelling out benjemins. depending on your car your probably gonna have to re-jet the carb tho. with the street avenger it was -2 on the primaries and +2 on the 2nd's i think

height issues was somethin i was worried about and did about a million measurements before the actual swap. i had an k&n filter on the car that was actually for a truck (ie: bout a inch taller) and that still fit. i got a stock filter from a shop near me that specializes in older mustangs and the weiand and holley togeather is just about the same height as stock intake and carb so everything fits with room to spare

word of warning......you will have to completely redo you accelerator linkage. and that was my biggest PITA