Struggle of a budget

[StanleyDSM]

Yeah I ve been ready and searching but I haven't found any clear info its mostly all scattered and bits and pieces. But I'll just find me a dohc and clean it up and stuff and put it on there. I'm also going to try and install a knock sensor on the block when I put the dohc since I have to do a little rewiring anyways for the injector resistor pack. Thank you all so much for the help!!

 

[wrenchspinner]

Okay I'll do that then. Oh and when I put the dohc
on, is it safe to go past 6k like only to 7k? And what size rods and pistons should I get?

The existing red line on your factory tach was never all that necessary and in DOHC trim you can get a lot more out of it by heading to around 7500.

The over square design of the stock 2.4 doesn't lend itself as well to the same high revs a 4g63 can do, but a fully built engine can handle brief sprints above 8k. That's not really the top end limit possible from this platform, but more of a safe and sane figure ;>)

 

[StanleyDSM]

Yeah I was wondering if I just goto 7500 every now and then if it will be okay.

 

[wrenchspinner]

In DOHC trim 7500 isn't a problem, nor anything to worry about, even on the stock internals.

I helped a buddy of mine DOHC and turbo his stock block (90k on it when we started) 4g64 Spyder with a big 16g/nice FMIC and a custom intake set up we made for it. He had it well tuned and ran it on 12-15psi with no issues for at least 3 yrs till he traded it in.

The car ran great and was a sweet pullin package for as little as he had invested in it.

That said, the best course is always gonna be to have solid internals if ya wanna boost it.

 

[StanleyDSM]

Okay cool deal, im gonna do the swap and get all the bugs worked out. Then I'll save a little more up and get new rods and pistons, I'll go ahead and replace the bearing and stuff too.

 

[wrenchspinner]

Though the 1G vs 2G head's been an ongoing debate for some years now I'd be lookin for a 2G DOHC head and intake unless ya wanna go draggin later on. Your stock exhaust will bolt up to either a 1G or a 2G head.

You won't need any special valve train stuff like aftermarket springs or cams for an NA set up. To my knowledge there weren't any DOHC cams made for an NA set up but turbo cams will do Ok.

When you get your head be sure to have it checked over by a decent machine shop to make sure the valves are sealing well and that your guides and seals are in good shape before installin it and it's never a bad idea to go ahead and install new cam seals, just to be safe.

Patience and persistance can pay big benefits when parts shoppin so try to use both to your benefit.

And ... knowledge is power, so keep studyin about every facet of your build as go. There's TONS of good info here and other places on the ol www.

One last thought, when installin the head, the correct installation of the timing belt will be tantamount to whether you wind up with a fun toy ready to hit the streets or takin that awful ride down to Bent Valve City.

Here's a link to a timing belt how to I wrote years ago that might be helpful http://tech.mirage-performance.com/4g6xtimingbelt.html. Since it was written before I had a digicam there aren't any pics, but I tried my best to make it complete and understandable.

 

[StanleyDSM]

Thanks alot, I'll see if napa can check the head for me. Yeah I was gonna do all the maintance I could while it was all apart. I'll check the timing belt out here in a sec. I have one more question for right now because I've been looking all morning and haven't really came up with anything. I want to use a 3g ecu BC my buddy has one for sale for 20$. And I know you can flash them. I need to know how to make the harness to connect to from a 3g ecu to a 2g ecu harness.

 

[97 eclenger]

there were dohc 4g64. but that was only in the 94 gallants in non turbo form. all you need is the 4g64 dohc gears and the dohc 4g64 timing belt. a 3g ecu can work but none were ever turbo. get a turbo ecu and if its a 5 speed match it to a 5 speed ecu. it won't pull power in high rpm as autos do. the 3g also didn't come with a knock sensor if i'm remembering correct. either get a black box ecu from a 2g or an evo 7-9 ecu

 

[StanleyDSM]

I have a knock sensor gauge in the garage for that that's why I was toying with the thought of a 3g ecu and plus BC I can get a hold of a 3g ecu better than I can a 2g ecu.

Plus you only need aftdi vag cable to flash it and a 12 power source.

 

[97 eclenger]

what i was mentioning the 3g working but none were turbo is just that they aren't set up for positive pressure in the intake. you can still make them work though but not with alot of boost.

 

[StanleyDSM]

Yeah Im not gonna be running more than 15psi for now. I just wanna know if anyone has a wiring diagram of a 3g to a 2g ecu harness.

 

[97 eclenger]

its the same as evo minus boost and 4g64 doesn't have injector resistors so thatd have to be added in to. i can get the wiring pinned out from my harness to the injector resistor but the 3g had a few wires different from 2g

 

[StanleyDSM]

I've already got the injector pack wired up and stuff, I just have to wire it in to the injectors. I'm just gonna use a mbc for now.

 

[97 eclenger]

i'm talking about the fuel table. the non turbo ecu is tuned to 100% load. turbo is tuned to around 300% load. over 100% load is where the boost is. but this is also where you can get in the ecu and tune it for boost

 

[97 eclenger]

wrong engine. spyder gs uses a 4g64 and 4g63. not 420a. but the turbo can be used

 

[StanleyDSM]

And yeah that's why I'm just gonna make a jumper and put a 3g ecu in it.

 

[97 eclenger]

its only like 6 or so wires you move. but its also stuff with a boost solenoid so itd be like 4 wires for you. id help if you were close to raleigh

 

[StanleyDSM]

Lol yeah its a bit of a hike from here to Raleigh. Now I'm having a problem. I'm trying to download ecuflash on my laptop and its giving me this.

This

 

[97 eclenger]

32 or 64 bit? windows 8 may be an issue to but i'm not sure. i havent gotten that far yet

 

[StanleyDSM]

64 bit and yeah good ole windows 8. Gotta love it. Lol

 

[97 eclenger]

make sure its compatible with the computer. i had ecu flash on mine. never had an ecu hooked up to it though.

 

[StanleyDSM]

Yeah I don't have it hooked up but I was just wanting to set it up on my pc. So I had it.

 

[97 eclenger]

it won't let you do anything. just the screen that says to hook it up to the car

 

[CrackedDSM]

Once again...there is no difference between the Auto and 5-speed 2G ECUs. None. Identical maps, identical code. I've got both .bins and .xdfs right now I can post if you want to look yourself.



Sigh.

 

[StanleyDSM]

Oh that's just saying too hook my car up to it?and cracked I'm doing a 3g ecu in my 2g BC I have more access to a 3g black box ecu.