DIY 98-02 Plastic IM/TB swap

I'll do a DIY for the swap for the IM/TB swap to the newer composite Plastic manifold.
Pros of the swap:
More power across the board
A decent sized Intake Plenum (OEM doesnt have one which means it doesnt breath well)
Equal length (and shorter then stock) runners
Heatsoak disappears
throttlebody swap choices open up due to the 4 bolt holes vs 3 stock
OEM drive ability and gas mileage

There are no cons

On to the swap Remove whatever intake system is on your vehicle, Upper + Lower RAD hose, and factory Intake manifold and assorted vacuum lines connected to it.

From here on out i've seen people do it differently then what i did but i copied what someone on TN had done so here goes

Needed are the IM/TB (with a weapon-r throttle rotor to act as the OEM one believe it or not)


90 Celica GTS radiator (moves the upper rad outlet a few inches to the right. bottom stays the same)
04 corolla PCV hose (VSV hose on MAP cars)
T fitting
some heater hose (have to get the exact size later)
And if your running a MAP sensor like me you'll need a piece of hose to fit on the bottom of the sensor and put it on the manifold ports. MAF cars wont need the T fitting they can run the 04 PCV hose from the valve cover to the IM and get a longer hose for the VSV (factory size) to the IM

Before you put in the new radiator put it together with the fans with some kind of bracket on top similar to this. once its in the car there's another piece that has to be cut but i cant get a pic of it.


Ok... Slide the IM into place (give the AC line a Tug) it should slide in. bolt it down. connect what vacuum hoses to the back manifold that you have.if you still have the stock rad in at this point you can see why it wont work. the rad hose crinkles up and would probably obstruct flow. A flexible rad hose could get you around this.

Slide the celica rad into place. its a fair bit wider then stock but it fits. the stock tie downs dont fit back. who cares?

jack up the car a smidge and negotiate the lower rad hose on. mine rests on the AC compressor but i havent had a issue. back up top the T fitting, 04 PCV hose and heater hose should all look like this when installed (still keep the stock pcv hose as well)


connect the upper rad hose and fill with coolant. get a buddy to hold the gas pedal down while you adjust the cable to make sure your getting full accel and full close. The bracket may have to be modified. after thats done take of the battery terminals to reset the computer. put them back on fire it up and be prepared for a stupid high idle (like 3 grand) for a few minutes while the car gets adjusted to everything. take it for a spin when the idle comes down and you feel the difference. it doesnt feel like the same car you had yesterday.
Before & After

Well the first dyno sheet is Intake/Exhaust. the second is after the Im/TB swap. numbers aside as i have a high mileage motor which looks better? the stock manifold drops torque after 5k like a rock and only has flat power when you cant use it.

meanwhile after the swap around 4 grand when the cam comes in everything is perfect and the car pulls. HARD.

Added: Dec 5, 2011 3:40 AM
The AFR's after the swap have worried me. i feel there is more power there if the car isnt being flooded with fuel. my car backfires its ass off.

two different dynos and 10K mileage between the two dynos. the dynojet dyno (W/ IM & TB) has Power, torque, speed, and air/fuel (speaking of their in the shitter). As far as rpm goes it lines up with the one above it. the main focus is the 2000-4000 rpm range where the stock manifold doesnt have enough air speed in it to make power or torque (thus the huge dip in power) and the 5000-6200 limiter where the stock manifold falls on its face in the torque dept. The 1ZZ-FED has this manifold for a reason. and even though my car doesnt rev as high i have a much smoother powerband and much more available power. and it sounds totally different.

Whats a Picture without sound genius?

Dosent sound or look like much other than a little traction loss.

http://www.facebook.com/photo.php?v=469950903030336

did you even look at the video?

You need to floor it! You were accelerating like a grandma, and what do you mean "first gear?" You drive an auto.

You do know that both automatic and manual transmission both have a certain amount of gears right?

Ya i pull waaaaaay harder than that with just CAI/TB/IM, stock exhaust. What exhaust manifold is that btw?

Yea... but you went out of your way to state that you'd be in first gear... which was for about 2-3 seconds then shifted to second and third like all autos do. It would have made sense if you stayed in first at like 10mph but I recall you reaching 50mph.

what else is new?

Exhaust leak plus automatic transmission. You have a stick right?

Yep, and no exhaust leak
Added: Jun 3, 2012 6:46 PM
are those the megan headers?

Dang I did not notice how bad that video was. I'll post something new soon. I got most things fixed right now. I just cant find that darn exhaust leak. ive pretty much boiled it down to the flex pipe itself.