[tacti]

well, i know it is not a recommended installation in any way, but my shop has installed Scion tC kit on my 2004 Toyota Solara.

My 4 cyl solara shares the same 2az-fe engine as scion tc, and installation went fairly smooth (i think) with some fabrication on the piping.

the dyno result was Max 203 HP with 207 Tq, and a/f ratio kept fairly steady around 12.5.

however, after driving for a little, i soon found the issue of my car stalling.
it happens when i start accelerating from stop and bring the rpm to around 3000, and then let the gas go. (Like stop and go between stop signs)
when i do this, first the rpm drops to 400 or so as soon as i let my feet of the gas, and then hesitate around there for seconds, and then go down to 200, 100 and stall

if i am driving on highway, and come off the ramp, just let the gas go and slow down, the car tend not to stall.

my shop has already double triple checked all the pipes and hose for any leaks, cleaned the throttle body, adjusting the bov, etc, and we still have the same issue.
they are checking and cleaning the throttle body one more time next week.

however, does anyone having similar experience or have any idea what might be the problem?

if everything fails, i guess i need to go for different piggy back, or find unichip tuner to re-tune the chip.

any help or suggestions would be appreciated.

Thank you.

Tact

[Robert]

Did you install the injectors that came with the kit? I would be very concerned about driving around with not engine management mapped to the new boost you are running.

[tacti]

everything from the kit has been installed, including the larger injector (630cc?) as well.
i have the unichip installed, and it is working except that one point when the rpm drop from the 3000rpm or so to the idling.

when the car is accelerrating or cruising, it keeps good a/f ratio.
the shop has told me that from the dyno result, even though they cannot tune (unichip cannot be tuned by non-unichip dealer right?), they told me the engine is safe for drive...

I am planing to do exhaust upgrade probably next month putting 2.5" piping with high flow cat and straight thru exhaust.
if i need to tune the chip, i would like to wait till i get the exhaust work done.
do you think it won't be safe?

Tact

[Robert]

Originally Posted by tacti

everything from the kit has been installed, including the larger injector (630cc?) as well.
i have the unichip installed, and it is working except that one point when the rpm drop from the 3000rpm or so to the idling.

when the car is accelerrating or cruising, it keeps good a/f ratio.
the shop has told me that from the dyno result, even though they cannot tune (unichip cannot be tuned by non-unichip dealer right?), they told me the engine is safe for drive...

I am planing to do exhaust upgrade probably next month putting 2.5" piping with high flow cat and straight thru exhaust.
if i need to tune the chip, i would like to wait till i get the exhaust work done.
do you think it won't be safe?

Tact

It should be ok if your shop feels it is but since the Unichip was mapped for the Scion I would seriously consider finding a Unichip tuner as soon as you can to get it tuned.

[tacti]

yep.
i've talked with the unichip tuner close to me, and probably i will be there soon.

exhaust should be installed soon as well.

Tact

[Ed 718]

It's hard to trouble shoot a kit on a car it was not designed for. The tune was based and tuned on a scion TC so everything is mapped out on that intenede vehicle.

[tacti]

update....

I took it to the unichip tuner, and he found the tuning is mostly fine.
the issue seems like the spring rate of the Blow Off Valve.

the spring is too tight and the vacuum is not strong enough to open the bov.
the tuner adjust the spring to the softest possible, and it got better.

now the question is are there any softer spring available to replace the one of raptor?

Thanks.

Tact

[Robert]

Originally Posted by tacti

update....

I took it to the unichip tuner, and he found the tuning is mostly fine.
the issue seems like the spring rate of the Blow Off Valve.

the spring is too tight and the vacuum is not strong enough to open the bov.
the tuner adjust the spring to the softest possible, and it got better.

now the question is are there any softer spring available to replace the one of raptor?

Thanks.

Tact

There aren't softer springs however if you hook up a boost reference in the charge piping before the throttle body to the bottom port of the blow off valve it should allow the valve to open much quicker.

[tacti]

Originally Posted by Robert

There aren't softer springs however if you hook up a boost reference in the charge piping before the throttle body to the bottom port of the wastegate it should allow the valve to open much quicker.

I'm not sure what is the boost reference.
is that something i need to drill and weld a port on charge pipe?
or is there something already there on the kit or factory throttle body?

Thanks.

Tact

[Robert]

Originally Posted by tacti

I'm not sure what is the boost reference.
is that something i need to drill and weld a port on charge pipe?
or is there something already there on the kit or factory throttle body?

Thanks.

Tact

Yes try teeing the line from the compressor tha5t goes to the wastegate now. That new line should go to the lower BOV port as well as the wastegate port when you are done.