WH-46 Jetting for a stock 2.5L 200???

[Smalltownbassin]

I just built a stock 200 2.5L and had a set of WH-46's to bolt on. These carbs had 80 mains. Will they suffice or do i need to step it up to 82 or 84 since they are on a 2.5? 34cc heads at 140ish psi if that makes a difference. Thanks!

[bullet123]

I run 84s and 86s in mine

[Smalltownbassin]

I run 84s and 86s in mine

The 86's in 1 & 5?

[bullet123]

I think my fat ones are 2 and 6. I just started a thread about this very subject

[Smalltownbassin]

I saw that but still couldnt get an answer. I think the WH-46 was originally used on a 2.4 right? If thats the case, the spec chart isnt any help at all. Are you running yours on a 2.5?

[Smalltownbassin]

I cant even find them to buy on the web. Are the Edlebrock and Holley jets the same size? 1/4 X 32 thread? I can find plenty of 0.084's for those.

[25two.stroke]

Search the web for merc jet chart or here on s&f...you will get the list of merc p/ns for the different jet sizes. They run like $2.5 to $5 a jet depending on size. Not the same as inboard jets. If you have trouble finding them I can order and send to you...

[bullet123]

I saw that but still couldnt get an answer. I think the WH-46 was originally used on a 2.4 right? If thats the case, the spec chart isnt any help at all. Are you running yours on a 2.5?

Yes, mine is a modified 2.5. I looked last night and my fat ones are 2 and 5. Its been a while since I messed with it. I jetted according to plug burn.

[rgsauger]

And you can always "make" bigger .086 jets by drilling your existing one(s) out with a number 44 drill bit. Get it where you like it and then buy the replacements if you choose. .084's (4) and .086 (2) is a good place to start with your compression.

[Capt.Insane-o]

I'm running 22s and am at 88s all the way around with an airbox. Motor turns 8200.

[rjdubiel]

I'm running 22s and am at 88s all the way around with an airbox. Motor turns 8200.

On my 2.5 245 carb with 20's and 46's I ran all the way down to 72 mains for drags, running a 20p prop and i was still fat. Ran 9K but was still fat (bog on takeoff and 1300+ EGT and dark plugs). I would never run down the river with anything less than 80's but that is what I found. Also i ran .062 idle jets and I should have went bigger on those.

[Capt.Insane-o]

A 20p is a lot different than a 31p that gets held tight for 15-20 miles.

[Merc 2.5]

Small-town bassin motor is a stock 2.5 200 with 120ish lb compression, most of the motors mentioned above are modified or highly modified, my guess without looking at the motor would b 82 will b safe. But it's got double oil for break in , so after that is done then he will be able to read pistons/plugs. I got jets if yall can pin down a day to do it

[Smalltownbassin]

Small-town bassin motor is a stock 2.5 200 with 120ish lb compression, most of the motors mentioned above are modified or highly modified, my guess without looking at the motor would b 82 will b safe. But it's got double oil for break in , so after that is done then he will be able to read pistons/plugs. I got jets if yall can pin down a day to do it

Its got 140psi now with 34cc heads. Thats the only mod though. We are gonna go ahead and put 84s in it i think just to be on the safer side since i have no idea how hard he is gonna be on it. Keeping the same 23P Tempest prop he ran with the 150 xr6 so it wont be loaded that bad too. Im gonna make a trip down to pickwick lake one weekend soon to check on it for him and read the plugs. Until then ive told him not to go over 4k with it. I may do what you suggested on the phone and swap him for my WMVs since they are jetted well for what hes got and i can play with the 46s since i have a better knowledge base then he does. I also have a network of people that can help when i have a question like yourself that he just doesnt have.

[Merc 2.5]

U need the 46s. Lol