So I have a 420a head that was given to me its been gone through my question is will it bolt up to my 4g63 blk? I have tried a google search on this topic but have no definitive answers. Any links would he appreciated as wrll. Thank you in advance

Got a hammer?
Seriously, though, how did you not get answers from a google or forum search? How is that even possible.. did you stop after the first result?
A google search gave me all the information I needed from this site, talk, dallasdsm, and so forth to determine the answer so I can only assume you didnt actually search. Nor did you even look at the deck surface of either head to see the similarities the two share. It may be a little blunt of a response but it just feels like a total lie or effort cop-out to me.

Simple answer: yes, they are interchangable.
Correct answer: no, not in the least bit. Two heads from two manufacturers for two entirely different engines.

You might as well try to fit a Chevy SBC head on Nissan SR20 short block.

There's a reason you were given the 420a head. It's a boat anchor that I wouldn't bolt onto a block that it is supposed to go on. Make aluminum ingots out of it or something.

Well now, harsh answers here....

No, 420a is a Chrysler motor originally designed for Lotus. Is also found in Neons, Avengers and Sebrings in 2.4l versions.

It will in no shape or fashion bolt to a 4g63 Mitsubishi motor. Diamond Star Motors really f*cked up going from 4g63 in the nonturbo 1G models to 420a in the nonturbo 2g model...then back to single cam 2.4 4g64 in the 2g Spyder

And, Paul Walker's famous lime green "Danger to Manifold" 2g Eclipse was a blinged-out 420a, blowing floor pans out no less....

please don't kill me either.

here is a 420a with a 1g 4g63 head on it with twin turbos.
and here is a 1g 4g63 with a 420a head on it

and here is the both of them

but NO they will not bolt up.


--sorry i just had to do it.

^^^ special cardboard headgaskets!! Just needs some mega manifolds to tie them all together Lol

Yes, there may be harsh answers, but in all seriousness.. if you asked a question like that in broad public without even looking at the mating surfaces or doing a simple google search, a wrench does not belong in your hand. Pay for somebody else to do the work. Responses like "we all started somewhere" need not apply because to be a mechanic you have to be at least somewhat analytical and willing to do research.

curt-s said:

Yes, there may be harsh answers, but in all seriousness.. if you asked a question like that in broad public without even looking at the mating surfaces or doing a simple google search, a wrench does not belong in your hand. Pay for somebody else to do the work. Responses like "we all started somewhere" need not apply because to be a mechanic you have to be at least somewhat analytical and willing to do research.

Click to expand...

I like to consider myself a smart ass because Im in no fashion a dumb ass. This guy obviously didnt know... perhaps this is his first 4g63 car and has never seen the mating surface?

I started off 420a..now Im hardcore 4g63. I turbo'd my 2g 420a because I didnt know what a 4g63 was. I didnt even know what an Evo was. I jus wanted more power. And this was in 2009, not long ago. I still learned alot though in my ignorance. Now I have a built Galant VR4... Cant be scared to ask a few questions....or pay someone to do your own work

Ask questions by all means, we are here to help. Not saying otherwise.
Just dont call it rain when it aint..

For example:
https://www.google.ca/?gws_rd=ssl#q=420a+head+on+4g63+block

First result is a tuners thread..
http://www.dsmtuners.com/threads/what-is-the-difference-between-420a-head-and-4g63-head.274044/

more from that search directly underneath the above:
http://www.dsmtuners.com/threads/diffrance-between-4g63-block-and-420a.421817/
http://www.dsmtuners.com/threads/can-a-4g63-non-turbo-head-be-used-on-a-4g63.271946/
http://www.dsmtuners.com/threads/difference-in-4g63-and-420a-heads-i-have-searched.225896/


It's a surprisingly asked question and it all results in the same definitive answer. So I can only surmise that the OP is trolling or lied about searching at all.

Well...google doesnt lie so the OP probably did.

Its all good, dustyboner proved that you indeed CAN have a 420a head on a 4g63 motor WITH twin turbos ...

To say google doesn't lie is false, heres why. Google simply re tells what it has found to be most searched topics. google can and does find wrong answers as well sometimes. Just being a stickler btw I loved that twin turbo setup on the 420a shit I didn't know you could blue tooth your turbo kits now

dustyboner said:

please don't kill me either.

here is a 420a with a 1g 4g63 head on it with twin turbos.
and here is a 1g 4g63 with a 420a head on it

and here is the both of them

but NO they will not bolt up.


--sorry i just had to do it.

Click to expand...

That... is the funniest thing I've seen in a while. Thank you good sir for the laugh.

The 420a head would bolt to a neon block so in reality you could possibly come up with some sort of srt4 dohc Frankenstein swap but I would be prepared to get new forged pistons connecting rods cams valves springs retainers head studs head gasket and upgraded fuel and ignition parts a turbo kit I believe eBay has a turbo kit specifically for the 420a and run the 420a intake manifold as well since a 420a block is being used already you can just use the neon transmission upgrade to stage 1 clutch and should be able to push high 300s on that setup as far as hp goes might get a little on the spendy side and getting that 4g64 block may bolt up just getting everything to work right might also be a bit of a task have you checked into a 94 block instead? If that works you would probably gain an extra 25 to 30 horse na compared to stock 420a na due to higher compression that would probably make the 400 hp range achieveable