Prelude Dual Carb Swap

[DeathRat]

It's my understanding that the only way to effectively use a dual carb setup from a 84 Prelude is to swap the Cylinder head over too? I base this on this thread >>>> https://www.3geez.com/showthread.php?...ight=Dual+Carb
Is this true? Reason being is I can get the dual carbs & intake for $20 CAN from the wreckers & my A20A1 single carb just doesn't have enough "oomph" for me.

[PhydeauX]

Yes you have to swap the whole head, the intake ports on the a18a are diferent then the a20. They problaby won't charge you more then another $30-40 for the head anyway (just make sure its still good). Its easier to remove the head to change the manifold then doing it with the head on anyway.

andy

[DeathRat]

What about my Distributor? OR should I grab that too?

[PhydeauX]

Its got a little bit more mechanical advance, other then that its the same part.

andy

[DeathRat]

Thnx! It's just while looking for a Air Intake to mod my present setup, I noticed 3 other Preludes there with Dual Carbs & then started thinking.....:super:

[4DoorAccordDX]

How hard is this swap? Will this eliminate most of the vaccum lines that we have now? What about emissions, how will it affect the Nazis down at the testing center? Just kinda curious what is involved, and how had it is to do. The lude has an A18 right? Will the heads match up as far as all the water passages and all that go?

Thanks in advance for any and all info.

2-Knee

[wannaswapab20]

u got to make sure u get a head off of a 86-87 lude only. from 84 back it will nto match up. the head off of the 86-87 head tho everythign matches up perfect, u have to get teh head bored out to a 2.0 also

[DeathRat]

Originally posted by wannaswapab20
u got to make sure u get a head off of a 86-87 lude only. from 84 back it will nto match up. the head off of the 86-87 head tho everythign matches up perfect, u have to get teh head bored out to a 2.0 also

So I still have to get the Cylinder Head bored too? Even though it's a "perfect" match?

[k-roy]

Originally posted by wannaswapab20
u have to get teh head bored out to a 2.0 also

Its the bore and stroke in the block that defines displacement, not the head. The head determines the compression ratio.

[POS carb]

yea, you may actually get more compression b/c the combustion chamber is probably smaller too

[DeathRat]

Originally posted by POS carb
yea, you may actually get more compression b/c the combustion chamber is probably smaller too

That's what I thought too......

[wannaswapab20]

hmm i dont kno guys i kno a few gusy with thsi head and blcok combimnatin on there ludes and they had to get the head bored to the same diameter as teh block.

[BMS]

Let's say that someone who lived in Cali wanted to try such a trick...I am sure that it'd still pass the smog test, but would it pass the visual inspection?

[funkytuqe]

hmm i dont kno guys i kno a few gusy with thsi head and blcok combimnatin on there ludes and they had to get the head bored to the same diameter as teh block.

Yup, i'm with you man, if want reiability and don't want to be detonating then get the head combustion camber done to have the same bore as the cylenders.

How hard is this swap? Will this eliminate most of the vaccum lines that we have now?

Hahahaha, have you ever seen under the hood of a stock prelude??? Vacume lines galore!!!! To complete he swap, you will also need the black vacume controll box that comes with the carbs and all of the vacume lines and a danm good manual to tell you where to hook them all up. Not worth it in my opinion, if you go with the Weber 38/38 you get more power than the prelude carbs and it will be one hell of a lot more easier. If you plan on a dual DCOE setup then yes get the prelude ET2 or A18 head.