4g64 8 valve sohc 1g specs

hello all,

just trying to get some basic info collected before i start tearing into this truck. this engine is in a 1994 mitsubishi mighty max std cab 2WD.

(1994) 4g64 8 VALVE SOHC ENGINE (non-MCA)

redline:
fuel cut rpm:
bore: 86.5mm
stroke: 100mm
deck height:
head gasket height:
combustion chamber cc:
compression ratio:
piston dome or dish cc:
intake valve dia:
exhaust valve dia:
cam lift intake:
cam lift exhaust:
cam dur intake:
cam dur exhaust:
lobe sep angle:
fuel injector cc:
spark plug: (NGK BPR6ES)
idle ign advance: 8*BTDC(as far as i know)



this is it for now, ill update this as necessary

Totally forgot to post this.

But if YOU have any of these specs. Please post them here

You can find them here on the forum too, just in case it doesn't happen fast enough.

:)Welcome to the forum

Thanks for the welcome. The reason I made this thread. Is because I was having a difficult time finding the info. It's so spread out and buried deep in threads I figured a stock reference for these things would be nice. I'd really like to get the cr and combustion chamber cc and redline. For the engine?

Combustion chamber cc: 47cc
Injector cc: 175cc
Timing: 3-7 degrees BTDC

(1994) 4g64 8 VALVE SOHC ENGINE (non-MCA)

redline:
fuel cut rpm:
bore: 86.5mm
stroke: 100mm
deck height:
head gasket height:
combustion chamber cc: 47
compression ratio:
piston dome or dish cc:
intake valve dia:
exhaust valve dia:
cam lift intake:
cam lift exhaust:
cam dur intake:
cam dur exhaust:
lobe sep angle:
fuel injector cc: 175cc
spark plug: (NGK BPR6ES)
idle ign advance: 3-7*BTDC()

thanks man, lets keep this up. on the compression ratio the research ive done the comp could be any where from 8.5:1 to 9.5:1. so i wanna narrow that down. and the redline!!! Brad, what is the redline for yours?

wellllllllllllllllllllllli can tell you all my research has came back that the 8-valve 4G64 has a compression ratio of 8.5:1 with a 68cc combustion camber, not a 47cc and they use FLAT top pistons. this can be seen by simply putting the 2.0 8-valve and 2.4 8-valve head side by side. the 2.0 has a 47cc combustion chamber and you can tell that it is much smaller than the 2.4.

BUTTTTTT, when the 4g64 was changed to a 16 valve SOHC then the combustion went down to 47cc just like all the other 4g63/4g64 16 valve motors but the pistons have changed to a dish to lower the compression.

Quote:

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Originally Posted by thehive

wellllllllllllllllllllllli can tell you all my research has came back that the 8-valve 4G64 has a compression ratio of 8.5:1 with a 68cc combustion camber, not a 47cc and they use FLAT top pistons. this can be seen by simply putting the 2.0 8-valve and 2.4 8-valve head side by side. the 2.0 has a 47cc combustion chamber and you can tell that it is much smaller than the 2.4.

BUTTTTTT, when the 4g64 was changed to a 16 valve SOHC then the combustion went down to 47cc just like all the other 4g63/4g64 16 valve motors but the pistons have changed to a dish to lower the compression.

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awesome info!! thanks alot man! that allowed me to reasonably calculate it for verification

almost got my list filled all the way in!


(1994) 4g64 8 VALVE SOHC ENGINE (non-MCA)

redline:
fuel cut rpm:
bore: 86.5mm
stroke: 100mm
deck height: (.4mm used in cr calc)
head gasket height: 1mm (approx)
combustion chamber cc: 68
compression ratio: 8.5:1 (figured by cr calculator)
piston dome or dish cc: 0 (flat-top)
intake valve dia: 46mm
exhaust valve dia: 38mm
cam lift intake:
cam lift exhaust:
cam dur intake:
cam dur exhaust:
lobe sep angle:
fuel injector cc: 175cc
spark plug: (NGK BPR6ES)
idle ign advance: 3-7*BTDC()

You guys need to be more hands on and less keyboard jockey :lol::lol::lol:

There are 6 different pistons (that I know of) used in the 4G64 and G4XX Hyundai engines (4 are in the 4G64). ALL of them are different dish and will net a different CR.

The 8V piston can NOT be calculated as a "0" because it is not even with the deck. That also doesn't account for the valve reliefs or anything. You need to measure them to get the correct number. Either pull your head off, or go to a yard and rip one off.

Head gasket height should be measured compressed. Approximations will only net approximated numbers.

Measuring the correct CC volume is also something you should measure yourself. Again, rip yours off, or go to a yard. The CC volume changed many times on the different engines.

I'm not trying to be an asshole (please don't read this that way), but you would be giving out all kinds of wrong info without using the correct specs that were actually measured correctly, and proven that you did it correctly.

Quote:

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Originally Posted by Merrill

You guys need to be more hands on and less keyboard jockey :lol::lol::lol:

There are 6 different pistons (that I know of) used in the 4G64 and G4XX Hyundai engines (4 are in the 4G64). ALL of them are different dish and will net a different CR.

The 8V piston can NOT be calculated as a "0" because it is not even with the deck. That also doesn't account for the valve reliefs or anything. You need to measure them to get the correct number. Either pull your head off, or go to a yard and rip one off.

Head gasket height should be measured compressed. Approximations will only net approximated numbers.

Measuring the correct CC volume is also something you should measure yourself. Again, rip yours off, or go to a yard. The CC volume changed many times on the different engines.

I'm not trying to be an asshole (please don't read this that way), but you would be giving out all kinds of wrong info without using the correct specs that were actually measured correctly, and proven that you did it correctly.

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hey man!:) thanks for chiming in, im no keyboard commando!, i dont own the truck. nor do i have daily access to it. im helping my friend with it as he isnt as mechanically inclined as i am.

i counted the piston as "0" because i dont have any way to measure the dish on it. also the deck hieght was accounted for in my calc. i approximated the compressed gasket height. everything is really for me to help him make choices on what he should do with his engine. i like to know about the insides before i go changing things.

thanks for the concern! btw do YOU know the redline or fuel cutoff rpm? is there a rev limiter?

I don't have the info on that. I'm trying to find my notes on the other engines for stuff like dish and clearance which I measured, but not sure what happened to them.

For future reference - if you calculate any piston with a "0" (because you don't have the info or whatever), you will get a very high CR. A 0 piston would be a flat top with no deck clearance, no reliefs and no dish at all. On the 8 valve, that would be somewhere around 11.5-12:1 (rough guess based on other combos I've built over the years, and the info I remember measuring).

Also - the head gaskets are different between the various generations of the 4G64. Earlier gens used a composite gasket while the later gens used MLS. They are different thicknesses. Due to the deck casting patterns, they are not interchangable so you should not use a MLS spec as a guide for your numbers. You also need the HG bore diameter when you calculate CR. It is not the exact same as the cylinder bore. That needs to be measured as well.

What are you trying to do with all the info? As in - are you trying to build some kind of monster NA 8V, or what?

Quote:

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Originally Posted by Merrill

What are you trying to do with all the info? As in - are you trying to build some kind of monster NA 8V, or what?

---

for me yes, this is what all my efforts and research has gone to but i definitely wouldn't call it a monster LOL. just a hot little 2.4 with about 11:1 compression and dual carbs. i know i could go for a DOHC turbo setup and i've had some in the past in other cars (my truck is not my daily driver) and they were very very enjoyable. but i kinda wanted to build a late 80's styled mini race/street truck with just basic electronics and a wire tuck with a MSD system.

its his daily driver, and he wants it to be more sporty, i suggested DOHC swaps, or a tubo build. we talked about supercharging. or just a high comp motor with a larger cam, but it needs to be reliable. so that throws out insane performance goals. idk ,i was thinking 250-300cc injectors, bumping the comp to 9.5:1-10.0:1 and adding the necessary fuel control. but he may just want it to be stock and reliable.

we might just do a health check at this point and start paving the way for a turbo build. who knows. but its always good to have the info that is not in the haynes manual. lol.

good info on the head gasket material!

its his daily driver, and he wants it to be more sporty, i suggested DOHC swaps, or a tubo build. we talked about supercharging. or just a high comp motor with a larger cam, but it needs to be reliable. so that throws out insane performance goals. idk ,i was thinking 250-300cc injectors, bumping the comp to 9.5:1-10.0:1 and adding the necessary fuel control. but he may just want it to be stock and reliable.

we might just do a health check at this point and start paving the way for a turbo build. who knows. but its always good to have the info that is not in the haynes manual. lol.

good info on the head gasket material!

http://i138.photobucket.com/albums/q...psgoa0eq6v.jpg

your fingernails are too clean!!!! im joking! THANK YOU so much for that post as im not buying a manual for his vehicle!

Quote:

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Originally Posted by Merrill

You guys need to be more hands on and less keyboard jockey :lol::lol::lol:

---

how can you call me a keyboard jockey? i plainly explained that if you take both the 8 valve heads off (like i have) and put them side by side the combustion chambers are obviously different sizes. and what does the 6 different pistons your talking about with the 4G64 even matter? because in this case per the thread title we are talking about the 4G64 8-valve motor. and yes it's 68cc. you wanna see my beaker and wintergreen alcohol set up? i may not post everything i do on here simply for the fact that i'm not a key board jockey and i really don't like sharing my info because people do just that and put you down and try to look smarter.

Quote:

---

Originally Posted by thehive

how can you call me a keyboard jockey? i plainly explained that if you take both the 8 valve heads off (like i have) and put them side by side the combustion chambers are obviously different sizes. and what does the 6 different pistons your talking about with the 4G64 even matter? because in this case per the thread title we are talking about the 4G64 8-valve motor. and yes it's 68cc. you wanna see my beaker and wintergreen alcohol set up? i may not post everything i do on here simply for the fact that i'm not a key board jockey and i really don't like sharing my info because people do just that and put you down and try to look smarter.

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dont worry about it man, i appreciate your input and value your time.

this is a rare occasion lol if you need more i can dig through my fsm

i hear you, ive been pulling apart a 2005 volvo s60r all week and my 74 beetle. and my friends truck.

the only thing im really looking for now is the redline?

Quote:

---

Originally Posted by thehive

how can you call me a keyboard jockey? i plainly explained that if you take both the 8 valve heads off (like i have) and put them side by side the combustion chambers are obviously different sizes. and what does the 6 different pistons your talking about with the 4G64 even matter? because in this case per the thread title we are talking about the 4G64 8-valve motor. and yes it's 68cc. you wanna see my beaker and wintergreen alcohol set up? i may not post everything i do on here simply for the fact that i'm not a key board jockey and i really don't like sharing my info because people do just that and put you down and try to look smarter.

---

We call this a joke.... you know, like "lol" kind of thing. Did you miss the 3 laughing smileys? You quoted them in your response. I never said YOU were a keyboard Jockey - I never said anyone specifically was. I merely wanted to grab attention for a moment so people would read what I wrote (which it worked lol)

I dont want to see a dozen people reading this post with the wrong info thinking they have a high comp beast of an 8 valve pooter... Thats why I offered up the info I have with the corrections I know are required for calculations.

The reason for the different pistons is to alert the unknowing that there are differences with many 4G64 engines (and others). Many of these are interchangable and even allow those to make an inexpensive hybrid of an engine. I only know of 6 different variants. There could be 7 or 8+. There may be 2 or 3 different piston setups between the wideblock G64, 6 bolt, 7 bolt, narrow, van..... You get what I'm saying? This could be important when calculating everything because your info may be different than someone else's that measured everything. That's why.

Now for the last part of your reply.... What I do is what I do for a living. That's no secret. I don't get on here and tell people how to make custom built race cars. I don't get on here showing my skills, tools and education off to make people like me. I have not put anyone down directly. I contribute what I can because it may help people. Take 2 seconds and realize I was making a contribution before you somehow read into a connotation as a negative directed specifically at you. Its JUST TEXT!!

Quote:

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Originally Posted by Merrill

We call this a joke.... you know, like "lol" kind of thing. Did you miss the 3 laughing smileys? You quoted them in your response. I never said YOU were a keyboard Jockey - I never said anyone specifically was. I merely wanted to grab attention for a moment so people would read what I wrote (which it worked lol)

I dont want to see a dozen people reading this post with the wrong info thinking they have a high comp beast of an 8 valve pooter... Thats why I offered up the info I have with the corrections I know are required for calculations.

The reason for the different pistons is to alert the unknowing that there are differences with many 4G64 engines (and others). Many of these are interchangable and even allow those to make an inexpensive hybrid of an engine. I only know of 6 different variants. There could be 7 or 8+. There may be 2 or 3 different piston setups between the wideblock G64, 6 bolt, 7 bolt, narrow, van..... You get what I'm saying? This could be important when calculating everything because your info may be different than someone else's that measured everything. That's why.

Now for the last part of your reply.... What I do is what I do for a living. That's no secret. I don't get on here and tell people how to make custom built race cars. I don't get on here showing my skills, tools and education off to make people like me. I have not put anyone down directly. I contribute what I can because it may help people. Take 2 seconds and realize I was making a contribution before you somehow read into a connotation as a negative directed specifically at you. Its JUST TEXT!!

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i say we all just let it go as i got the drift, and i understood you. because you know i really would like the ability to edit my original post after i get this all said and done.

I think you will be able to edit it after 3 more posts.

Keep all your good info coming Merrill - you are just trying to keep us all honest and out of trouble. Experience is the best teacher, and your experience with all the various combinations you have seen will help with coming up with what will work for the application.

This is a good idea for a thread -- hopefully it can be fleshed out and added to with time. There is so much confusion about these values and there are so many possible combinations of pistons, blocks and heads. See my signature.

im pretty thorough, so it should e finished, with the correct specs for my engine(my friends)

You guys have looked at the 216 manual thread right? It's all there....soft. downloadable...

and here are my manuals

http://www.mmeierle.com/mighty%20max%20info.htm

and if it'sa 94 its a 7 bolt motor...slightly different than a earlier 6 bolt (considered better by some)

just google it.

I've run 16:1 compression but I've had my combustion chambers reworked. currently running 10:1 with boost.

here are the numbers I've gathered building 2 race motors the numbers are stock.

SOHC, 8 valve, non MCA head, 13 1/4" bell housing
Base engine Horsepower Torque
2.4-liter SOHC I-4 stock 116 hp @ 5000 rpm 136 lb. ft. @ 3500 rpm
2.4-liter SOHC I-4 Modified



Displacement 147C.I. 2405 CC
Deck Height 9.244 in.
Inches MM
Bore 3.445 87.5
Stroke 3.937 100
Rod Length 5.9 150
Pin Bore 0.827 21
Big End Bore 1.89 48
Crank Rod Journal 1.771 44.98

OEM Valve Sizes
MITSUBISHI Inches MM
Intake Valve 1.811 46
Exhaust Valve. 1.496 38

Head (A) Stock
Chamber CC's 68.8

Cam Duration (stock) 264/264
Compression Ratio 8.4

wow, that was unexpected! im surpised i didnt stumble on that sooner!

Now you have the Balance Shaft delete conundrum to solve, to do or not to do....

more resources. mostly 4G63 based but the motors are practically identical except for bore, and deck height, and crank throw. The Rods are identical.

http://www.vfaq.com/index-main.html

idk he might leave the balance shafts or do a stub shaft swap, couldnt say.