could it really be that easy?

[Mr_Efficiency]

I have a 90 GP with a 3.1 and I'm looking to turbo it, I have no problem fabing up all the plumbing, mounting brackets, etc I'm curious about the wiring, I know how to easily fool the computer into never seeing boost but I like the idea of having everything under ECM control and I was curious if it was as easy as using my stock 3.1 NA harness and ECM and just simply use a TGP chip and of course change the injectors (yellow tops) and map sensor (2bar) so the chip can function seeing as that is the equipment it was programed to use.

could it be that easy? I cant see why it wouldnt work cause the only reason the stock wiring cant take boost is cause of the map sensor being a 1 bar and you cant just plug in a 2 bar map cause the chip cant read it, but if you have a chip for a 2 bar map along with a 2 bar map i dont see any reason for it not to work, and obviously the injectors need to be changed cause the TGP chip is programed for bigger ones, am I missing any other diffrences in wiring?

thanks

[TurboSedan]

yes, you can use a regular 3.1 NA wiring harness and ECM, as long as you use a TGP chip, injectors and 2-bar MAP sensor.

 

you will need to modify the wiring harness a little but it's no big deal.

[TurboSedan]

kinda curious, what DOHC cylinder head are you using for your Sunbird project (in your sig)? or are you using a completely different 2.0L engine? sorry to go off-topic.

[Mr_Efficiency]

its ok, my question is pretty much answered, lol

I'm using a regular sunbird block with a 91-94 crank (for DIS which btw never came on a turbo sunbird) and pistons and rods from a C20LET which is a twin cam turbo version of this motor over in the UK that uses the same block, these rods and pistons are forged and have the valve cuts for the extra 8 valves (regular turbo sunbird internals only have forged pistons not rods) as for top end I'm using the head off a twin cam daewoo leganza (or nibura, same thing) that motor also uses the same block, and the intake is from a turbo sunbird but with the daewoo flange welded to it so I can stick with the turbo harness, everything exhaust side is totally custom, and the tranny is a getrag hm282 from turbo sunirds (and only turbo sunbirds, cause of there oddball bell housing) and obviously a custom chip cause of the air flow diffrences in 8v and 16v, 3 bar map and a few other goodies, planing on 17 psi with a two stage boost controler so I can maybe get a half decent launch, also toying with propane injection that kicks on in the second stage of boost cause of its 110 octane which i'm gunna need running 17 psi

going to be one hell of a car when i get done with it

I also found if I use 99+ Nbody steering knuckles up front with a 98+ F body caliper braket and 11" rotors I can use aluminum corvette 4 piston calipers, and I'm planing on a 99+N body complete independant rear with rear discs. I have a huge list of mads to this car, its going to be a dedicated race car with a full cage, only two seats, 5pt harness, no interior other than the majority of the dash, and fiberglass doors, fenders, hood etc, and fully adjustable coil overs on all four corners.... but I'm still on the look for a mint shell to put all this into, I already striped a turbo sunbird for all i needed from it and I have the coilovers and most of the suspension, motor is still in progress and tranny is in the corner waiting until I come up with the money for a LSD.

 

wait i just re read the first post and realized it said "you will need to modify your harness a little but its no big deal".... what is this little modification I need to do?

 

and dont be shy with the sunbird questions, i get that alot with any forum i go to and besides that car is were 80% of my dedication lies, I love it to death.

[TurboSedan]

that sounds like a cool project!

 

as for the wiring harness - if you use a NA 3.1 wiring harness on a TGP engine you'll have to:

 

- lengthen the O2 sensor wires since the TGP O2 sensor is right in the turbine inlet, not in downpipe

 

- cut a small slot in the MAP sensor connector so it will fit the 2-bar MAP sensor. easy with a Dremel and a thin cutoff wheel

 

- lengthen IAT wires, since the TGP has an IAT in the plenum over by the alternator not in the airbox

 

- as for the boost controller, i used a grainger valve MBC. i actually did use a TGP harness (only because i already had it and it was in better shape). i think some people have gotten rid of the digital EGR, used a vacuum EGR instead and then used the wiring for the TGP wastegate solenoid? something like that. maybe someone else here knows more about that. i never did bother with it even though i could have just plugged the TGP wastegate solenoid in and used it. i liked the g-valve, although!!! if you do go this route i would look into using a solenoid and maybe using 2 g-valves, one for low boost and another for high. the W-body Getrag 282 is geared very steep (3.77 1st gear + 3.61 FDR) and traction will be a big issue. 2nd gear is steep as well. 1st gear was completely useless. a TGP engine can make alot of torque down low. i think i dyno'd 337wtq at about 3400 RPM. at 13-14psi i would get traction in 3rd gear. 3rd and 4th gear were nice

 

if you use a 5-speed you'll have to do a few more modifications for that (i think Tony has a post dealing with this).

[Mr_Efficiency]

thanks alot, for the 5 speed wiring isnt it just a matter of wiring up the park neutral saftey switch?

I'm not using a TGP motor, just a regular 3.1 and bolting on a turbo, I guess I'll have to tap a hole in the intake plenum for the IAT since thats were the TGP chip is expecting the reading to be comming from, thats no big deal, I figured I'd need to extend the O2 sensor wires, and yes I plan to use a two stage MBC just like I mentioned on my sunbird, I have a plumbing diagram for a way to route two MBC's together and allow you to switch between the two through a switch, this switch can be operated by hand or by some kind of trick switch on the tranny so it only limits it in first and maybe even second gear, or you could do an RPM window switch, whatever you choose.

I would have never knows about the IAT relocation, that would have made the ecm throw a bit of a fit on me, as for the MAP sensor I'll just wire in the plug from a turbo sunbird, i have a few turbo sunbird harness sitting around here I can cut up and steal sensors from. was thinking of using a sunbird turbo, its a T25 just like the TGP bit i got a really good deal on a rebuilt one out of a turbo dodge, its a T03 50 trim, better design and a fair bit larger.

 

[GutlessSupreme]

Just an fyi, the Sunbird T25 is smaller than ours.

 

Also, here's my post on wiring changes for the 5 speed swap.

http://www.w-body.com/forum/index.php/topic,61879.0.html

[Mr_Efficiency]

awesome thanks for the link, I forgot all about the cruise control stuff, another thing I never thought of until now that wasnt on that list was the reverse lights, everytime I've done a 5 speed swap its always been in a race car and i never have to worry about all that stuff. great write up btw.

I have two friends who have 3.1's with plans to turbo them and they both gave up cause they couldnt figure out a way to get the ECM to read the 2 bar map, I told them to just get a TGP chip but they just said "good luck finding one" lol, for some reason they dont seem to understand you can just buy them, I cant wait to get this together now and show them how its done

thanks guys

[TurboSedan]

thanks alot, for the 5 speed wiring isnt it just a matter of wiring up the park neutral saftey switch?

I'm not using a TGP motor, just a regular 3.1 and bolting on a turbo, I guess I'll have to tap a hole in the intake plenum for the IAT since thats were the TGP chip is expecting the reading to be comming from, thats no big deal, I figured I'd need to extend the O2 sensor wires, and yes I plan to use a two stage MBC just like I mentioned on my sunbird, I have a plumbing diagram for a way to route two MBC's together and allow you to switch between the two through a switch, this switch can be operated by hand or by some kind of trick switch on the tranny so it only limits it in first and maybe even second gear, or you could do an RPM window switch, whatever you choose.

I would have never knows about the IAT relocation, that would have made the ecm throw a bit of a fit on me, as for the MAP sensor I'll just wire in the plug from a turbo sunbird, i have a few turbo sunbird harness sitting around here I can cut up and steal sensors from. was thinking of using a sunbird turbo, its a T25 just like the TGP bit i got a really good deal on a rebuilt one out of a turbo dodge, its a T03 50 trim, better design and a fair bit larger.

 

 

i'm not sure what size the Sunbird T-25 is but the TGP T-25 has a .80 A/R compressor housing and a .68 A/R turbine housing.

 

only thing that kinda sucks about the Turbo Dodge T3 turbo is that most of them have a Chrysler specific turbine inlet flange. it's just like a standard T3 flange but one of the bolt holes is spaced a litle further out so it doesn't have a rectangular bolt pattern. not really that big of a big deal, the turbine housing is just kinda small....i'd rather have a larger .63 A/R housing. the only T3 turbo from a Turbo Dodge that has a true standard T3 turbine housing bolt pattern are from the DOHC 16-valve Turbo-III cars (Spirit R/T and Daytona IROC R/T). they are also a little bit bigger than the Garrett T3 found on the SOHC Turbo-I and Turbo-II engines. either way, even that small Garrett T3 from any Turbo Dodge would probably be alot better than the TGP T-25.

 

i kinda did the same thing you are doing; i turbocharged a previously NA 3.1 with TGP parts. i have a huge thread on that project here:

 

http://www.w-body.com/forum/index.php/topic,22683.0.html

 

i sold that car about 2 months ago and bought my Spirit R/T.

[intern8tion9l]

hey TurboSedan, how did you go about wiring up the IAT? i don't think mine's hooked up right now and my mechanic friend thinks it might have something to do with why my a/c won't work

[TurboSedan]

when i turbocharged my car i used a TGP wiring harness so i didn't have to do any wiring.

[Mr_Efficiency]

thanks for the link, I was unaware the chrysler had its own specific flange, i just always assumed it was a T3 flange. anyways its not an issue cause I'm making my own crossover and flange for whatever turbo i end up going with.

I'm actally tossing around the idea now of droping in a 3X00 and turboing that, once the motor is in its the same ammount of work to turbo it, and I'd trust i alot more than my 367,000km motor! Also if i buy a 3X00 I could rebuild it with LS1 springs and maybe a little thicker headgasket to lower the compression to help with reliability.

since this is my thread I can highjack it, lol... Anyone see any added issues with running a turbo 3X00 off a 3.1 harness with the above mentioned modifications (relocated IAT, 2 bar map and yellow tops) only thing i could think of is i might need a custom chip due to the extra airflow cause of the heads.