2.4 n/t

[Dsm810z]

Website will not allow me to post in the short block section yet, so here it goes. I've read til my eyes bled on this subject and now just need some clarification for a n/t application.

Some of you know of my recent transmission catastrophe, and were very helpful in providing information to match up a 2g fwd turbo transmission to my 1g talon with a 6 bolt 4g63. I had everything mounted up correctly and my Talon ran better, shifted smoother than ever before... for two days. On day 3 of just getting the transmission, axles, clutch, and flywheel installed the engine overheated and fried the head, internals, etc... When my stock transmission blew and fell down on the crankshaft it obviously caused more internal damage than I thought. The general consensus is for me to scrap my DSM, but I cannot bring myself to do it so I have decided to go with a 2.4L n/t swap. All my external engine components on my blown 4g63 are brand new so I can just swap everything over to the g4cs, excluding the timing belt and cam gears, of course.

I'm going to use a g4cs block with a 1g 4g63 head. My cam choice will either be BC 280s or FP4s. Any other recommendations?

Now, as far as internals go, I've read that that if I use 1g rods with stock g4cs pistons this will yield an 11:1 compression ratio. Remember, this is a n/t application so I am not shooting for a compression ratio for running boost. Is this a reasonable compression ratio for a n/t street car? Are there any ways to tone it down just a bit to about 10:1 or 10.5:1??

What size fuel injectors will I need to run the 2.4L n/t setup?

Thanks in advance for all the help,
Chris

 

[mysticj]

1) Cams: BC272 or FP2

2) G4CS and 1G head: compression is more like 12:1. You will need the thickest HG available.

3) Fuel Injectors: 275cc from the 94+ Galant, 96+ 2.4L Eclipse. Will need a fuel computer.

 

[Dsm810z]

May I inquire as to why you say the FP2 cams over the FP4s? All I've read about the stroker 2.4 setup is people using the BC 280s or the FP4s. Is this just for their turbo setups??

I was planning to run a safc to control the fuel and maf, is this suffecient?

And is there any way to tone the compression ratio down a bit?

 

[Dsm810z]

Let me add that this car will be driven quite a bit. Its purpose is not to be a track car at all, just a powerful street car. Are there major problems for this setup to be driven daily?

Bastarddsm, did you mean that smaller cams would help with the compression, or am I reading your post wrong?

 

[mysticj]

I choose the FP2 simply because it's the biggest cams to work with the stock valve springs for the money, plus you are running a NA setup. These cams are good enough for your setup. Use the thickest head gasket to lower compression.

 

[bastarddsm]

Let me add that this car will be driven quite a bit. It's purpose is not to be a track car at all, just a powerful street car. Are there major problems for this setup to be driven daily?

Bastarddsm, did you mean that smaller cams would help with the compression, or am I reading your post wrong?

With 272's you should be perfect.

I was stating that the larger a cam is it generally has a later intake valve closing meaning it bleeds off more cylinder pressure at low rpms.

The fact that this happens allows a high static compression ratio to be used on the street.

 

[Dsm810z]

How much will my compression be lowered using thicker head gaskets?

Thank you for clarifying, this information is very helpful.

I was actually thinking about going with FP or BC valve springs/retainers. If I'm building a motor, I want to do it right.

 

[bastarddsm]

How much will my compression be lowered using thicker head gaskets?

Thank you for clarifying, this information is very helpful.

I was actually thinking about going with FP or BC valve springs/retainers. If I'm building a motor, I want to do it right.

I couldn't tell you how much the compression will change, you will have to determin the cc's of the g4cs piston, and the 4g63's head. Then calculate it out.

If your gonna get springs, look at kigglys beehives. they are the shiznat.

 

[mysticj]

After your calculations if the compression is still too high for you, you can have the area around the valves open up. Increasing the head cc will lower compression, IIRC.

 

[bastarddsm]

After your calculations if the compression is still too high for you, you can have the area around the valves open up. Increasing the head cc will lower compression, IIRC.

Yes, it will...but that area is the squish pad...that helps fight detonation. If your remove it, you could end up worse off.


Realistically with 12:1, 93 oct, and big cams you should be fine.

 

[Dsm810z]

So let me clarify real quick:

1) hks 272s or BC 272s

2) Thick head gasket (about what thickness should I be looking for that would hold up strong?)

3) stock g4cs pistons

4) 1g Eagle rods

5) those kiggly springs are a much steeper price than the BC's >.< Would the kiggly springs be completely necessary just for a street car? I was thinking the BC's would be more than suffecient.

Are the 89-92 sonatas the only source for aquiring a g4cs block?

Just a matter of curiosity, how much would the compression be brought down if a 4g63t head was to be used?

 

[mysticj]

1) Hks 272, BC272 or FP2

2) Check aftermarket HG makers like Comestic, etc for their thickest off-the-shelf HG.

3) If you get a stock G4CS block

4) The stock rods are fine. Maybe shotpeened, optional not required.

G4CS or any 8-valve 2.4L 4G64...The N/T and Turbo heads have the same head cc.

 

[dsm-onster]

Yes, it will...but that area is the squish pad...that helps fight detonation. If your remove it, you could end up worse off.


Realistically with 12:1, 93 oct, and big cams you should be fine.

I would recommend a lower temp thermostat. I wouldn't be suprised if he got some det. He can always pull some base timing if he get's a little ping. Also, a little ping with an n/t motor is nothing as hard on a motor as knock with a decent amount of boost.

I agree with MisticJ about the fp2 cams. I'd like to add another option. Delta regrinds makes hks 272 profiles on your stock cams. And after the core is returned you're out 180 for the pair. They even ship the shims to put below the lifter. Fp2s are at 212 duration at .05" lift hks 272s are at 213 duration at .05" lift. Fp2s have more lift. But hks 272s have a little more overlap. Since you have an na motor, overlap will really help topend as your back pressure won't push the exhaust gases in to the intake as with a turbo setup seeing it's potential. Also, you have higher piston speeds with the 2.4 motor, so you will idle better with the overlap and your low end will not suffer as much.

And 1g rods ARE g4cs rods. The 6bolt g4cs block has the same rod as the infamous 6bolt 4g63 block that can handle 600whp

The brake specific fuel consumption of the n/a motor is much lower than a turbo motor. You don't need the energy to spin the turbocharger, which sometimes requires 80-100hp to meet the flow demand of a 350-400whp goal. With a BSFC of .45 vs .55 with a turbo motor, you can get away with the stock 240s up to about 220crank hp, or about 195-200whp. The stock turbo 1g 4g63 is rated at 195hp at the crank . But if you can get those galant injectors and ecu that MisticJ is recommending, I strongly advise it. With good cams and a 2.4 you might be able to get more than 200whp.

Raising CR is a freeby WRT fuel. You can up comression and gain power and your BSFC will just go down. It won't require more fuel to keep up with the higher HP output.

. . . With mistiJ's advice and someone to bounce ideas/issues off of, I'm doing a very similar project: a 4g64 in a 1g n/t lase. You can see what's going on in my blog catagory on it. Click. 4-2-1 header with 2.5" exhaust, ram style CAI, cam upgrade. g4cs/4g67 head (with the 4g64 SA block I'll be only running 10:1). I tink I can seriously make the same 0-60 or 70-90 or hp as a FWD 4g63 turbo parts swap to this n/a 4g63 car. So for the same cost as putting on all the turbo stuff, I'll have the same or better torque, same peak power and the ability to run 87octane.

 

[Dsm810z]

What if I were to use the g4cs block and 4g63 head with the dished pistons from a 4g64, would this lessen the chance of det?

Is there a difference between a 6 bolt 4g64 and the 6 bolt g4cs? I do not want to use a 7 bolt motor of any kind. So far I've only found one source for the g4cs block (89-91 sonata). What is another source vehicle for either a 6 bolt 4g64 block or the 6 bolt g4cs (if there is one)?

Will a safc be suffecient for tuning the 2.4L?

 

[dsm-onster]

Safc will be fine.

Stick with the g4cs. I think it has the holes in the block for mounting the front roll stop. I'm not sure about the 6bolt 4g64. Otherwise the rods between ALL 6bolt even down to the g4cn/4g67 1.8 motor are all the super strong 6bolt rods. Which are heavy and absolutely NOT neccesary for your build. You'd have to go past 400whp for the even 7bolt rods to be a concern. I wanted to run the 7bolt 4g64 motor with my build to lower the reciprocating mass and I'm trying to do this on 87octane. It's not like I'm goign to see over 300whp with this thing.

You would have 9.5:1 CR with the 64SA pistons and 9:1 with the 64S pistons. I think that a little lower than what one would want for a good n/a build. It's not all about flow with n/a as much as it's about displacement AND thermal efficiency, reducing other pumping losses, and increasing VE.

There's nothing wrong with running a little bit more compression than what pumpgas likes there's options:

1) You have a 1g car, you can just retard your base timing in the worse case situation and be fine. Remember the 100mm stroke likes less timing because of pistons speeds. And higher compression likes less timing because of a faster burn rate. Pulling timing doesn't mean you lost power. It probably would put you closer to Mean Best Timing.

2) As I mentioned you may get away with just running a cooler thermostat, many n/a builds out in the v8 world where higher comrpession is involved jsut require such a thing.

3) You could also do as MisticJ suggested. Unshrowd especially the intake and exhaust valve on the timing belt side (that one is more shrowded than the other side for some reason). This will increase volume in the CC and lower compression. You'd be trading compression for flow. But if nothing works to kill the det, you could pull the head and try that. Add a thicker headgasket and the final volume could increase 7-10cc

 

[Dsm810z]

The question about the pistons was more a matter of curiosity than anything else.

I'm having trouble locating a 89-91 sonata for the g4cs block, but I have found a 89 galant. Are there differences between the 6 bolt 4g63 and the 6 bolt g4cs? My understanding is that the 89-91 sonata was the only model that had the g4cs block, is this correct??

 

[dsm-onster]

You'll have to wait for MisticJ to get back on. He would know

 

[Dsm810z]

I'm looking into getting the HKS 272 regrinds from Delta cams. Do I need to upgrade the springs/retainers to run these?

 

[mysticj]

NO unless your springs are weak(i.e. warp, age, etc.)
G4CS is also find in the 85-89 Galant. I have to make sure...

 

[dsm-onster]

I agree with mysticj again. Too many run these cams on stock springs for you to worry about the profile. Especially considering the powerband of the 2.4 motor is even lower for a given cam duration than a 2.0L motor. You'll be good to go as long as teh springs are within spec.

All you need with the regrinds are the shims they provide.

 

[mysticj]

You don't have to spend a lot of money on a project like this.

 

[Dsm810z]

o.0 I think this is the only time I've ever heard that I don't have to spend a lot of money on a project aewsome!

 

[dsm-onster]

I think he's saying that for a relatively cheap budget, $600-800, one can get a nice n/a build up done with these platforms. As he's told me before, mitsu has put everything there for us in various cars for a real nice frankenstein na motor and made enough of them so that we can get the used parts rather affordably. This is the premise that the honda tuner crowd has based there budget builds on for years. Getting the best parts for the goal from a plethora of factory built options. these motors are all remarkably interchangeable: 4g61, 4g63, 4g64, 4g67/g4cn, g4cs. Different piston dishes/domes, different strokes, different intake manifolds and head ports, different head chamber volumes. There's alot there to work with. If you have a scored block and you're going to rebuild, you could do something as simple as bore the 4g63 out .06" over and swap in g4cs flattop pistons from a JY and have 11:1 CR vs. the stock 9:1 and have a 2.1L motor. 4% more flow and another 15hp easily from the higher compression. Or you can make a high compression 4g64 with a head swap and have nice torque with a 2500lb base model T/E/L.

If you can affort the used parts to swap in a turbo, you can afford a nice n/a build up. It's just another route to take.

 

[mysticj]

o.0 I think this is the only time I've ever heard that I don't have to spend a lot of money on a project aewsome!

You really don't...it's the 4G63 that is the money pit!
The major concern is which ecu to use and what type of cams to run.

 

[Dsm810z]

Can I not use the stock ecu if I tune with a safc?