2.5 CB N/A into 2.4 vehicle, with 2.4 head???

[RoadWarrior222]

Hi folks,

I've got a decent 2.5 common block N/A bottom end and working A413, it occurs to me that I might pick up a 3rd gen van with 2.4 and busted A604 for peanuts, but in otherwise great shape.

So that starts me wondering if I could pop the 2.5 CB and the A413 under the 2.4 head. I'm guessing I might have issues with engine mounts, any easy solutions? I'm also unsure if there were any sensors that the 2.4 'lectronics need to have on the bottom end. Is there a crank position sensor?

I'm figuring the driveshafts should fit and the spark etc should be no problem, PCM may or may not throw a fit from losing the 604.

Or am I going about this the complicated way and the A413 should bolt to the 2.4 anyway (for some reason I'm thinking it doesn't)

thanks for any clues.

RW222

[turbovanman²]

That should be a great swap, not sure what compression a 2.5 n/a with a 2.4 head would be but should be good for a DD.

The A413 will bolt to the 2.4 block if you use that but it moves the starter around. I would honestly find a Neon A413 if your using the 2.4 as the mounts will be right and no messing around. I am sure you could make the Neon A413 also work on the 2.4 block. I have a Neon A413 core if you need one, ;)

The 2.4 uses cam and crank sensors, coil pack etc so you'd be better off keeping the 2.4L or if running the 2.5, you'd need to run a standalone system.

[RoadWarrior222]

Thanks, looks like the crank sensor would be the spoiler really, was wondering if it could be done quick and dirty... haven't got the ambition to mess with standalone, was wondering if it was doable on stock electronics. Coilpack etc wouldn't be an issue...

I was thinking I'd seen somewhere that a N/A 2.5 bottom end on a N/A 2.4 head makes a handful more HP than a 2.4, possibly a few points more compression or something, well it gets a couple more cc too, whoopdedoo.

Wait a sec, just thunk, how much clearance would there be over the dizzy hole? Just thinking about possibility of rigging a crank position sensor output from a carved up dizzy, since I won't need it for der spitzensparken.

[16vconvert]

I was thinking I'd seen somewhere that a N/A 2.5 bottom end on a N/A 2.4 head makes a handful more HP than a 2.4, possibly a few points more compression or something, well it gets a couple more cc too, whoopdedoo.


I'm running a 90 2.5 Tbi bottom end , slightly clearanced stock pistons , 95 2.0 dohc head and cams , My tq@2400 rpm was 132 ft-lbs my HP climbed steady to 5200 rpm @ 110 Hp , where i stopped .
I'm currently getting 24city 29hwy so far.

this was on a mustang dyno at at the last Megasquirt meet in richmond Virginia , I'm not sure if there's a correction that goes with a mustang dyno ?

[RoadWarrior222]

Crazy idea...

Take a 3.0 dizzy with the optical timing disk, paint out some of the high data rate slots so there's groups of 4 like the notches in the flywheel that a cranks sensor picks up. Fudge the signal so it looks like the output from the hall effect sensor. Bodge 3.0 dizzy into 2.5 hole or adapt optical timing crap to fit on 2.5 dizzy shaft...

Guess I need to find angular specs for the timing of those slots though.

[turbovanman²]

Crazy idea...

Take a 3.0 dizzy with the optical timing disk, paint out some of the high data rate slots so there's groups of 4 like the notches in the flywheel that a cranks sensor picks up. Fudge the signal so it looks like the output from the hall effect sensor. Bodge 3.0 dizzy into 2.5 hole or adapt optical timing crap to fit on 2.5 dizzy shaft...

Guess I need to find angular specs for the timing of those slots though.


You'd need a degree in math for that as it would have to be bang on, :eyebrows:

[RoadWarrior222]

Okay, chuck the disk, get piccie of flywheel, reduce to right size, paste onto margarine tub lid, cut slots where the slots are, cut out, install over optical pickup, shim with any combination of duct tape, JB Weld and cut up beer cans to fix minor issues...

[contraption22]

Is all this work really that much of a better solution than replacing the A604?

[RoadWarrior222]

Just as soon as I get a tri-corder that tells me whether an A604 is good or not at the push of a button, I'll agree.

[t2_85_lebaron]

i know a guy whos trying to fit a 2.4 neon head on a 2.5 or 2.2 block. he says it bolts up but the oil passages are offset

[contraption22]

i know a guy whos trying to fit a 2.4 neon head on a 2.5 or 2.2 block. he says it bolts up but the oil passages are offset


Been done, many times.

[contraption22]

Just as soon as I get a tri-corder that tells me whether an A604 is good or not at the push of a button, I'll agree.


How about a 5 speed, or 3 speed auto swap?

[RoadWarrior222]

I figure the issues with getting a 5 speed in a 96 up van would be similar or worse.

Really just trying to figure out how I can use spare stuff I've got to my best advantage, ubercheapskate style.