8G I4 to V6 throttle body swap

[SPD_FRK]

SPD_FRK, wont you need to port the IM on the I4 to accomodate the Diamante TB I would assume?

That is something that may have to be done, but I will recheck some of the measurements on it and post back with what I find.

[qnz]

i didnt see you mention putting the gasket back on. You should get a new gasket to prevent vacuum leaks, and in the future, boost leaks ;)

[4g63lover]

i didnt see you mention putting the gasket back on. You should get a new gasket to prevent vacuum leaks, and in the future, boost leaks ;)

ah. you're right. I did mention not to lose it though, hopefully it can be a common sense thing to put it back on. lol.

I'll replace the gasket when I bypass the coolant lines. I have no evident vacuum leaks at the moment.

[RedGalant2k1]

If memory serves the Diamante TB is as big as 70mm.

[M-Rod]

Hmm.. I heard 68mm somewhere for the Diamante TB. I may have to take mine off and measure it up. Maybe it even varies by year.

[03-Galant-ES]

I try. lol. Seriously though, I owe it to Adrian. He gave me the idea. This is one of the best mods i've done to my car recently. Not to mention it's not an expensive mod at all.

SPD_FRK, wont you need to port the IM on the I4 to accomodate the Diamante TB I would assume?

Diamante 3.5 with coolant line bypass sounds nice. Isnt the diamante a bolt on affair for the 6g72 so I believe we could use it

[4g63lover]

Diamante 3.5 with coolant line bypass sounds nice. Isnt the diamante a bolt on affair for the 6g72 so I believe we could use it

it is a bolt on affari but its a matter of matching the Intake manifold and throttle body to each other to get a consistent airflow.

[SPD_FRK]

If memory serves the Diamante TB is as big as 70mm.

Hmm.. I heard 68mm somewhere for the Diamante TB. I may have to take mine off and measure it up. Maybe it even varies by year.

M-Rod is dead on, the Diamante TB is only 3mm larger in bore than the stock 6G72 TB, if you are doing a bigger bore TB on the V6 platform do it right the first time and find an Infiniti Q45 90mm TB.

[4g63lover]

Whoa, the stock 6G72 is 65mm? I coulda sworn it was only 60mm.

[Poison457]

ok so i did this swap, looped the coolant lines and used the v6 tps sensor and gasket, i'm having a major problem when i start the car it revs up to around 4k then bounces back and forth from 2k to 2.5k "i have a 4g64 btw", i thought the TPS sensor was bad so i went back to my old one same exact problem i adjusted the throttle cable back to about where it was with the I4 throttle body made no difference "because the cable was way to tight at first butterfly was open a good portion".

So now i'm stuck the car runs isn't throwing any codes but rev's like crazy, trying to adjust the tps sensor just makes it rev higher but constant, realy need some help here heh.

[4g63lover]

have you turned the idle screw all the way to close?

Have you checked the IAC? My idle revs up to 2300-2500 RPM at first start up but after a couple minutes it goes down to 700-800 RPM. But I did throw an IAC code though...

The position of the throttle cable for the V6 TB compared to the I4 is in the EXACT same position, so that shouldn't be a problem. As long as you can feel slack move the cable in and out you should be okay. The I4 TB is the same.

My issue didnt only happen after I looped the lines. It also occured when I had the coolant lines running to the TB.

I'm 98% sure it's the IAC for me, because it would've thrown a different code otherwise. Considering everything else is copecetic, which seems to be the issue since it drops back down to normal idling speed once warmed up.

So check the IAC for sure.

BTW, I am throwing an IAC code but the light isn't on, so make sure to check it anyway.

[sponcar]

so can we use the TB from the diamante on our 4g64..??? or not???
just wondering cuz I found many diamate on the local junk yard....

[Poison457]

4g63lover,
in your tut you said "i was lucky to have the IAC to" lucky is definitely the word for it heh, the new style iac run's on vacuum the V6 throttle body has a larger bore IAC port than the I4 IAC port by i'd guesstimate 2-3mm give or take .5mm therefore using the I4 IAC is not possible, you have to use the V6 IAC so you get the proper vacuum to the IAC sensor and get the correct idle speed, how i came to this conclusion.

after tinkering with it all night long adjusting throttle cable tension, swapping out the TPS sensor's, adjusting the TPS sensor position, even pulling out a multimeter and adjusting per the service manual, i finally got it to idle steady at 3.5k rpms, car ran fine no codes 100% drive-able, if you call the idle speed in drive 1.5k rpms drivable, so i finally said phooye and was switching back to my stock throttle body.

I decided to take a close look at all the small differences between the two and that's when i noticed the IAC port, it's significantly larger on the V6 than the I4 "significantly for vacuum purposes anyways". finished putting on the I4 throttle body car runes perfect. so my conclusion is you need the IAC from the V6 to make this swap, i don't have the means to get one right now and test the theory but i'll update it about a week and let everyone know.

Poison

Edit
to further this theory i pulled the part #'s for the IAC's
I4 acdelco 2171827 OEM 89053340
v6 acdelco 2171821 OEM 89053334
so looks like i'll be heading back the junkyard in a few days trying to find an IAC for a v6

Edit 2
according to the service manual the I4 throttle body is 54mm, and the v6 is 60mm i'm going to bore out the intake manifold to match the v6 throttle body when i get the new IAC and will post up pics and info on performance

[4g63lover]

my IAC is for the V6.

Thats some good info poison.

[M-Rod]

so can we use the TB from the diamante on our 4g64..??? or not???
just wondering cuz I found many diamate on the local junk yard....

Yes, as long as you use the throttle body from the 6G74 engine. Just make sure you get the pigtail harness from the IAC.

[sponcar]

^ok ok thanks guys...

[galantofva]

I just got my v6 throttle body from a junk motor at work today. Does bypassing the coolant cause a CEL? Also what size line and how much do I need to do the bypass?

[SPD_FRK]

I just got my v6 throttle body from a junk motor at work today. Does bypassing the coolant cause a CEL? Also what size line and how much do I need to do the bypass?

There are no CEL's that come with doing the bypass. You need I believe about 8-10" of 1/4" ID hose, and some clamps to do it.

[sponcar]

Yes, as long as you use the throttle body from the 6G74 engine. Just make sure you get the pigtail harness from the IAC.

btw those are the only things that I need for this swap???
sorry if I sound like a noob... but me dont know too much about perfomance...

[galantofva]

Poison457 I am having the exact same problem. Only difference is mine was reving to 3k steady. I hit the gas and took it to 4k and then it started bouncing between 2500 and 3k and holds steady at 1500 at idle in drive. I will try to get a v6 IAC first thing in the morning and I will let you know if that helped.