I was under the impression that DOHC doesnt have huge gains in low HP N/A. I remember seeing dyno graphs somewhere of some hondas DOHC and SOHC with same everythign else and the SOHC made its power sooner and peak was the same.
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I was under the impression that DOHC doesnt have huge gains in low HP N/A. I remember seeing dyno graphs somewhere of some hondas DOHC and SOHC with same everythign else and the SOHC made its power sooner and peak was the same.
but the DOHC has more aftermarket support, such as intake manifolds, different cam profiles, better springs and retainers.(for the galant )
And for the pistons not clearing the EVO head idk if they do, the kia pistons do have valve reliefs cut into them, but if you are worried about that, just have custom pistons made for the 4g64 with the 63 for higher compression
Thats kind of weird i think that might come down to cam tuning. I would think the DOHC would have the larger power band since the cams could be tuned individually. With that said for a everyday car torque numbers make the big difference in thinking if your car is fast. So ill definitely be looking at torque numbers when tuning.Quote:
Originally Posted by qnz
O im not concerned about it, i just dont see the reason to run a comp evo head.Quote:
Originally Posted by mrg7243
exactlyQuote:
Originally Posted by exhaust power
Ideally with a DOHC setup your gonna want the largest valve possible and a cam profile that supports your power goals and drivability concerns.
If you build is really budget minded and looking to gain only about 80whp or so over stock. I would start doing some research on how much valve clearance exists on the stock 8g SOHC setup. The reason I ask is because if there is a good amount of valve clearance, nothing would stop you from removing the stock SOHC head, having some porting done and having the head milled down (the math here is going to be CRITICAL) which would increase the final compression, and even ordering a custom headgasket thats thinner than stock (again raising the final compression). With budget in mind custom head gaskets are cheap, probably about $75. By going this route, you save the money in buying parts associated with the DOHC swap, re-use your stock stuff (which you know is good if your motor is healthy) It will allow your money to be spent on the RPW cam, header and potentially a custom intake mani or ITB setup. Im sure you could get it tuned on an EVO ECU instead of a standalone (again, saving money)
I've never seen an NA SOHC honda break like 170 hpQuote:
Originally Posted by qnz
I've seen NA DOHC Honda's break 300 hp
Comestic makes a .027" HG which will bump compression by 0.3cr. I wrote something awhile back that the 8G Galant had two different compression ratio: 99-00 had 9.5 while the Cali spec and 01-03 had 9.0cr.
You can't run big lift on the G4JS pistons, valve pockets too small plus the Evo head don't flow well without ported/polished for large lift.
http://i40.photobucket.com/albums/e2...2YqvmnW_ph.jpg
I seen a NA DOHC 4G64 putting down about 170whp.
milling the head is another option. But if the expenses out weigh the sonata pistons then it would be considered .this wont be done on my current engine since its my daily i would buy a jy engine and rebuild it .Quote:
Originally Posted by Stewi
What i can do is buy a 4G64 drop the G4JS pistons in get the head ported and drop it in the g like that. then ill just keep on tuning and upgrading on the go this will save me money in the short run instead of doing everything at once then i can get different dyno numbers at different stages i upgrade.
I can send my head off to my teacher(robert lauer) but im not sure what the price is on his head porting. I should just call him but i wouldn't pay no more then 300 . anyway hes a professional and builds panoz motors for lamons series back then.Tought me things i wouldnt ever find out about N/A building.
good info.Quote:
Originally Posted by mysticj
Rpw makes different stage 2s that dont require valve springs/and retainers so i guess that would be mild enough to run with pistons . But technically there should be some numbers floating around on club 3g about the valve piston clearances to paint better details. I need to do more digging, cause right now im bouncing around from sohc to dohc and which would be the better set up. first i need to form a theory price list for both and start from there.
I couldnt disagree with that more.Quote:
Originally Posted by mysticj
A stock unported, stock valve size EVO head has been tried and tested time and time again to make over 600whp on boosted applications, there is no reason it couldnt flow enough volume to support 300whp N/A. Granted the port and polish will help it a good bit, but its definetly not required.
lol... I am glad to see that other members are interested in going the route Brandon went...
I have a picture comparing the Dohc Kia head to the stock 8g I'll post it up I anyone wants to see it
more pictures the better!
Think I might pick up a set of dc sports headers for the fun of it
http://i40.photobucket.com/albums/e2...cture074-1.jpg
Kia at the bottom 8G at the top
some random Kia head pics
http://i40.photobucket.com/albums/e2...Picture085.jpg
http://i40.photobucket.com/albums/e2...cture075-1.jpg
http://i40.photobucket.com/albums/e2...cture076-1.jpg
i wish i had more pics but i guess some got lost
yours is ported, how much though??
Ok i did some research and didnt know stand-alones cost so much. As stewi said to go with a evo ecu, i was also thinking about the manual eclipse ecu. Now i remember SDP_FRK explaining into detail about remapping the the eclipse ecu and stuff of that sort. So is the eclipse ecu a possible option? because theres a couple at the jy for less then $50 bucks wich is friggen cheap compared to internet and i dont want to see how much a evos cost lol.
What to do for injectors or do i even need them? some where on tgc i read about the injectors and some one was talking about they max out 230 (whp-hp? idk). I dont really know too much about our injectors, but if some one could spread some light on this it would be very interesting to talk about. Im keeping in mind WRX injectors if i end up maxing out the 4g64's. Also Are the G4JS injectors the same as 4G64S?
Ok Spark/Ignition. To my knowledge I probably wont have to do any tunes ups on this system except for plugs or am i wrong? also does any body have any veiws on direct ignition? I read a while back that they arent anything advance, performance wise.
Ok heres my list for now i went a head and split parts up in stages to help keep down short time consumed money. The stages start with parts need 1ST and goes down till i reach basically luxury items.
Stage 1 (well needed)
G4JS DOHC/Pistons
blox 264/264 cams
adj cam gears
CAI
6G74 TB
Stage 2 (needed but drivable W/out in theory)
2.5 E/H
ECU (EVO maybe eclipse manual)
Tune
Stage 3 (may need, luxury, power)-the Tune will tell me what i need
wrx Inectors
Warmer Plugs
Evo I/M
fuel pump
Ill think of more if possible.
Either the Eclipse, Evo, or Lancer ECU will do. The Evo is a tad expensive, the Lancer ECU become an Evo ECU when flashed. :)
I'll suggest adding these items to Stage 1: Evo IM, Blox 272/264
Sounds good for the ecu possibilities. I have the EVO IM in stage 3! lol . AndQuote:
Originally Posted by mysticj
Running a more aggressive intake cam then exhaust? whats the benefit? And i believe ill need new springs to match the 272.
you can flash your stock ECU. no need for an evo ecu.
really? I was under the impression that it wasnt flashable. Dont know where i got it from but ill do some digging.Quote:
Originally Posted by qnz
You can flash the Galant ECU with the 2.0 cable, regardless of 99-03 model years. Though the Galant ECU is flashable, and some will likely use it, it still is a "band-aid" solution once you are 5pd swapped IMHO.Quote:
Originally Posted by qnz
If you want it done properly, 4cyl should simply swap directly to an Evo ECU since it has the Knock Sensor, where as the Galant and Eclipse ECU does not.
The V6 platform simply just swaps over to the Eclipse M/T ECU.
The reason I say to swap to an Evo (4cyl) or Eclipse (V6) Ecu is simply because you have about 30+ wires that are not needed in the harness once you are swapped to the 5spd. Just leaving the bundle of wires, or running a dual ECU setup, or intermediate harness are all what I personally view as a "band-aid" solution...like it or not, it is the truth when it comes down to it.
Doing the wiring and swapping over to the full ECU is pretty easy that I am confident in most of the people here that they can do it themselves...considering what many have been able to do already.
More overlap..G4JS springs sux...Must upgrade.Quote:
Originally Posted by Exhaust power
More over lap isnt necessarily good in a N/A engine but could work. The basic purpose of over lap is when the exhaust opens up 1st then the intake opens up 2ND while the exhaust is still open. Thus getting most of all the bad combusted air/fuel mixture out. this will help bring a greater % of clean air in when combustion happens.Quote:
Originally Posted by mysticj
now we have a more aggressive intake . In theory now i think of it the torque curve at max torque will probably stay the same and in the higher rpms torque should be better then a 264 intake. Do to the fact that even if the intake opens early into the exhaust stage(4 cycle) the exhaust is still closing on time. And when in high rpms(max hp) the cylinders dont fill up with air as much at max torque. Now with a more aggressive intake cam the intake will open a bit early and at high rpms fill the cylinder with more air before compression happens. thus making more torque since horse power is a function of torque itll make more horse power as well.
so in theory the benifit would be like advancing a regular 264 intake with out shortening the power band.
Now when you throw in other things as compression ratio running a cam too big might hinder performance. And one other thing who knows how my car would idle with that 272 cam? around a 900 rpm idle is favorable for me. Ill stick with 264/264 for now and down the road if needed power experimental like the 272 cam could be explored. If thats what your going to run i wanna see some numbers! sorry for the speach just giving out info
I'll let you know the results of the 272/264 in a few months...
went on you tube to see some 272/264 set ups and they sound pretty sick and idle about stock. Ill just need to see dyno numbers.
the 99 and 00 models are now flashable? did they finally update it? I tried to do mine a while back and it wouldn't workQuote:
Originally Posted by SPD_FRK
Last time I checked only the 02-03 are the only years. Maybe I'm wrong.
thats what i thought too i ddnt know 99-01 ECUs were flashableQuote:
Originally Posted by Isaurio
you need the tactrix 2.0 cable for the older models
Thought the information of flashing the older ECUs was posted over here already, guess not.
As he said, though you will need the appropriate definition file for the ROM files yet which is being worked on.Quote:
Originally Posted by qnz
Whitch cable do you need for 01-05 ecm
yeah i have the 2.0 cable they must have updated it if it works now
I guess todays my day to start my build, i just got G4JS pistons. Im still not sure if i want to do the DOHC head swap. So im sticking to the SOHC theory for now.
For the 2nd time i been in turbo car and i must say ill be more then happy to be 180-220 whp N/A lol
my friend has a turbo 2nd gen neon running 10 psi on a small diesel turbo(oxymoron) and it halls. but the thing i found cool was he was doing tunes on the run. Seeing the potential of tuning on the run seems very exciting and satisfying.
Get 7g replacement pistons, they have deep dish and will clear any valves. They have 9.5:1 CR
SOHC sucks donkey balls
9.5:1 is kinda of low for N/A and i already got the sonata pistons. Im not worried about clearance i read on 3g forums one guy had the pistons in with no problems. SOHC just seems more straight forward and cheaper in the short run.Quote:
Originally Posted by mko
and as i said before the 4g69(rpw.com) put down some decent numbers with bolt ons 4g64 shouldn't be too far behind.
btw are you talking about the 7g DOHC pistons? i have no idea where the ratio will be go (up or down) with the G4JS head and 7g pistons.
7g SOHC and DOHC pistons are identical. The difference is in the head chamber. 7g SOHC has 9.5 CR and the DOHC has 10.0 CR. Replacing the head with hyundai 1.8L head with smaller chamber brings it up to 10.7-11 CR. BUt thats for 7g.
So for 8g in theory, you already have the Sonata 2.4L pistons, and between the 3 choices you have - Kia, Sonata and Evo8 heads, you need the one with the smallest combustion chamber that will bring up the compression.
What is the stock Sonata compression with DOHC head - 10 -10.5:1? This compression will change once you use these pistons with SOHC Galant head, and that change will most likely be in the negative i.e will bring the compression down i.e youll end up with the same setup you have now with stock Galant piston CR.
ok i see what your saying with 7g heads.Quote:
Originally Posted by mko
The G4JS DOHC engine is 10.0:1 and the 8g sohc is 9.0:1. The sonata pistons are higher compression because they sit a bit higher. I cant remember the cylinder head cc's but the hyundai head is bigger. Using the sonata pistons with the sohc will yield around 10.5-11.0:1 CR.
Im sure some body has to know the exact ratio since alot of us do the DOHC swap for turbo builds.
IDK man it makes no sense.
Pistons at TDC sit flush with the block. Higher sitting piston or offset wrist pin piston is used only for stroker builds.
If the Sonata pistons are higher sitting then they will most def. come in contact with the head which is obviously not good.
If the statement, that 99-00 Galants have 9.5 CR and the 01-03 galants have 9.0 CR, only leads me to say that early 8g galants were still using 7g style 9.5 CR pistons and later 8g were made with flat pistons and 9.0 CR.
Do you know for sure that the SOnata has bigger combustion chamber than the 8g SOHC chamber? Because if the Galant has more cc's in the chamber then youll end up where you started - stock CR galant. And then youd have to make a choice - go DOHC for more compression or get another set of pistons.
I wish my theory is wrong and youre right. That will save you a lot of headache.
I know my 00 galant pistons are flat top pistons, i think all of them are 9.0 cr