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View Full Version : Who knows their 2.4l blocks?



Shadow
02-14-2013, 11:33 PM
Looking for specific info on the 2.4l blocks. I'm guessing the turbo block is the strongest, but has anyone Really checked them out? Anyone sonic one of these blocks yet and know how thick the cyl walls are?

I know that a lot on here run the N/A 2.4 block, but I also see a lot of failures compared to the turbo block.

So, a sonic on the N/A block for comparo would be cool as well :)

turbovanmanČ
02-15-2013, 01:19 AM
I know this has been brought up before, just did a quick search but found nothing. The earlier blocks IIRC are the same, turbo/n/a, the later blocks, 2000+, the turbo's had piston oil squirters, and they can be added to the n/a blocks if need be.

glhs399
02-15-2013, 01:30 AM
http://www.enginebuildermag.com/Article/3542/rebuilding_the_chrysler_24l.aspx

Here is a pretty good write up of the 2.4. Not too specific on the block changes. I've never looked at a non turbo 2.4.

contraption22
02-15-2013, 10:28 AM
There is no difference between turbo and non-turbo blocks 2003-up. Same casting. Turbo blocks were drilled for piston squirters.

What kind of "block failures" are you seeing?

Shadow
02-15-2013, 01:23 PM
I'm not seeing any failures, but I thought Rob Pachner broke a 2.4 block and I seem to remember a couple others, Dean maybe?

Good to know on the castings and makes sense, why cast two different blocks. So 2003 and newer would be the way to go as I'm thinking they are probably stronger as well.

Still interested in cyl wall thickness.

thedon809
02-15-2013, 01:32 PM
03+ is NGC electronics though.

Shadow
02-15-2013, 02:08 PM
03+ is NGC electronics though.

No sweat, I'm only interested in the Block :)

turbovanmanČ
02-15-2013, 02:09 PM
I'm not seeing any failures, but I thought Rob Pachner broke a 2.4 block and I seem to remember a couple others, Dean maybe?

Good to know on the castings and makes sense, why cast two different blocks. So 2003 and newer would be the way to go as I'm thinking they are probably stronger as well.

Still interested in cyl wall thickness.

People broke them due to the bedplates not holding, ala high HP DCR cars etc. Bedplate straps fix that but also remember, these guys are running 1000 + whp.

zin
02-15-2013, 02:59 PM
Here's an interesting article Hot Rod did, mentions some block differences, though nothing about bore thickness...

http://www.melaniff.com/srt-4/hot%20rod/hot_rod_2003_09.htm

Mike

thedon809
02-15-2013, 03:10 PM
No sweat, I'm only interested in the Block :)Trying to run it off our electronics? Ive always read on neons.org you cant use an ngc engine in earlier cars without swapping to ngc wiring and pcm.

contraption22
02-15-2013, 03:23 PM
Trying to run it off our electronics? Ive always read on neons.org you cant use an ngc engine in earlier cars without swapping to ngc wiring and pcm.

You can run them on 2.2/2.5 electronics if you hang a distributor off the side.

turbovanmanČ
02-15-2013, 03:32 PM
You can run them on 2.2/2.5 electronics if you hang a distributor off the side.

Yep, and Rbryant makes the adapter.

shackwrrr
02-15-2013, 04:00 PM
03+ has a different head and that head has different manifolds. There is an extra vent/drain on the back of the block going to the head. This passage can also interfere with our starters on the back.

Shadow
02-15-2013, 04:07 PM
Trying to run it off our electronics? Ive always read on neons.org you cant use an ngc engine in earlier cars without swapping to ngc wiring and pcm.

If someone on that site has a sonic map for a 2.4l I might believe them.............:)

RoadWarrior222
02-15-2013, 07:22 PM
BTW these used a totally different casting technique than 2.2/2.5 blocks and shouldn't have hidden thin spots and seams. So cylinder wall SHOULD be fairly regular.

ohiorob
02-17-2013, 10:30 AM
looking at the blocks side by side i see nothing that would indicate that the one is stronger then the other, no extra webbing or anything like that. Ilike the older heads because of the bigger ex. valves and better choice of spark plugs.

Rob, the only way to find out what block is better is that you need to do the sonic test your self because no one else will .

a block would last me a little over a year befor #3 cyl. would split on the back side, alwas in the same spot. could be the block or it could of been that #3 injector was always a little weak . it failed completly last time out .

Force Fed Mopar
02-17-2013, 10:40 AM
Will a 02-older crank fit in a 03-up block?

BadAssPerformance
02-17-2013, 05:38 PM
I'm not seeing any failures, but I thought Rob Pachner broke a 2.4 block and I seem to remember a couple others, Dean maybe?

As OhioRob chimed in, yes, he's cracked a few cylinders. Both Dean and I have had oil pump failures but no block issues.

For turbo vs. early non-turbo, the one theory I heard was the extra oil return rib strengthens the back side of the block between 3&4. Not sure if this is needed.

As for DCR crank straps, they will tell you that you need them on a mild build, but FM advised they didn't think they were neccesary below 1000hp. remember the firey pic of Crawford's pro neon? That was over 1000whp, no crank straps.

For some reason this thread reminds me of the old 8V on a 2.4L block discussion:

http://www.turbo-mopar.com/forums/showthread.php?33045-2.4L-8v-hybrid

turbovanmanČ
02-17-2013, 08:06 PM
looking at the blocks side by side i see nothing that would indicate that the one is stronger then the other, no extra webbing or anything like that. Ilike the older heads because of the bigger ex. valves and better choice of spark plugs.

Rob, the only way to find out what block is better is that you need to do the sonic test your self because no one else will .

a block would last me a little over a year befor #3 cyl. would split on the back side, alwas in the same spot. could be the block or it could of been that #3 injector was always a little weak . it failed completly last time out .

Interesting, how many blocks have you cracked?


Will a 02-older crank fit in a 03-up block?

I would say yes as the only change was the crank reluctor, and if you using a dizzy, that doesn't matter.

Force Fed Mopar
02-17-2013, 10:57 PM
I would say yes as the only change was the crank reluctor, and if you using a dizzy, that doesn't matter.

But if you were trying to put an SRT engine into a earlier Neon or Stratus, it would...

Shadow
02-20-2013, 03:09 PM
looking at the blocks side by side i see nothing that would indicate that the one is stronger then the other, no extra webbing or anything like that. Ilike the older heads because of the bigger ex. valves and better choice of spark plugs.

Rob, the only way to find out what block is better is that you need to do the sonic test your self because no one else will .

a block would last me a little over a year befor #3 cyl. would split on the back side, alwas in the same spot. could be the block or it could of been that #3 injector was always a little weak . it failed completly last time out .

I figured as much on the sonic checking as I've found pretty well no one does this and IF they do get it done, it's by their machine shop and they don't pay any attention to the results anyways.

Thanks for the info, I was pretty sure you cracked 1, but I didn't know it was this many and in the same place each time.

---------- Post added at 01:09 PM ---------- Previous post was at 01:06 PM ----------


As OhioRob chimed in, yes, he's cracked a few cylinders. Both Dean and I have had oil pump failures but no block issues.

For turbo vs. early non-turbo, the one theory I heard was the extra oil return rib strengthens the back side of the block between 3&4. Not sure if this is needed.

As for DCR crank straps, they will tell you that you need them on a mild build, but FM advised they didn't think they were neccesary below 1000hp. remember the firey pic of Crawford's pro neon? That was over 1000whp, no crank straps.


Agreed, we've never even considered strapping a block, even for 800WHP because we knew it was all BS hype from the beginning. All of those failures were from bad harmonics. Balance everything right for the intended RPM and even the stock crank will go 1000WHP wothout issue.

Now having said this, anyone who likes the feeling of added protection, go right ahead and strap away, I didn't say this to offend anyone :)

Force Fed Mopar
02-20-2013, 08:41 PM
So what about the people that say you can't really balance a 4-cyl? Something about 4-cyls being inherently unbalanced and best you can do is match rod and piston weights...

zin
02-20-2013, 09:06 PM
You can balance any engine, and the rougher the design the more you'll get for your dollar, so to speak.

What I think you're referring to is the fact that a 4cyl engine can't be built in perfect balance due to the number of cylinders and their configuration. An early 90* Chevy V-6 (4.3L), or even a Buick 3.8L are good examples.

Because of the angle of the "V" and odd number of cylinders on each side, they will fire unevenly, inducing a vibration or couple that is difficult to (if not impossible) to balance out via counterweights. Just like our 2.5, they have been built with balance shafts meant to cancel out the vibration, kind of like adding 2 dummy cylinders to make it think it's a V-8.

In-line 6s and V-8s (and variations on these: V-16 V-12) are "naturally balanced", which is to say they fire on an even number of degrees and have a mate to each cylinder to balance things out.

The four cylinder can't match an in-line 6 or V-8 for smoothness, just doesn't have the overlapping power strokes, but that doesn't mean you don't balance them.

Hope the above makes sense, I kind of feel like I'm not getting the point across...

Mike

moparmorrell
12-23-2013, 04:01 AM
You can balance any engine, and the rougher the design the more you'll get for your dollar, so to speak.

What I think you're referring to is the fact that a 4cyl engine can't be built in perfect balance due to the number of cylinders and their configuration. An early 90* Chevy V-6 (4.3L), or even a Buick 3.8L are good examples.

Because of the angle of the "V" and odd number of cylinders on each side, they will fire unevenly, inducing a vibration or couple that is difficult to (if not impossible) to balance out via counterweights. Just like our 2.5, they have been built with balance shafts meant to cancel out the vibration, kind of like adding 2 dummy cylinders to make it think it's a V-8.

In-line 6s and V-8s (and variations on these: V-16 V-12) are "naturally balanced", which is to say they fire on an even number of degrees and have a mate to each cylinder to balance things out.

The four cylinder can't match an in-line 6 or V-8 for smoothness, just doesn't have the overlapping power strokes, but that doesn't mean you don't balance them.

Hope the above makes sense, I kind of feel like I'm not getting the point across...

Mike

Never really thought of it like that but makes total sense