neil Gueldner

iTrader: (1)

I've read all the threads I could find on the 13bt swap, but I have an question.

I bought an S5 T2 motor, and my goal is a reliable, emissions legal setup with 200 wheel HP. I'm looking to keep my investment relatively low and my reliability high.


My planned setup:
stock S5 ECU, turbo, stock ports, injectors, intercooler, etc.
some type of cone air filter
Fuel cut defender
Mazdatrix 2.5" DP to a Bonez 12A high flow cat - stock 12A midpipe, RB power pulse muffler.
Possibly a piggyback computer
I'm looking to boost close to 10psi

My question is about the exhaust. The cat is roughly 1.75" ID pipe. What size is the stock exhaust on the T2? How much of a problem is the small exhaust from cat to tailpipe? I know the best thing to do is replace all that, but I'm trying to keep the costs and decibels down.

Anybody have experience running something similar?

steve84GS TII

Right here.
You wont find many people running full S5 setups because of the electronic OMP.There is no way to run that OMP directly on an FB front cover.But,the electronic OMP must be retained in order for the S5 ECU to work.
I got around this by having my SE front cover built up and machined to accept the big S5 OMP.You can also run premix and block off the OMP pad.Then,plug the OMP into the wiring harness and tie it off to the side.

200RWHP will be easy with a S5 since they make 200 crank HP right out of the box.A 2.5" downpipe and 2.5" exhaust system will help a lot.3" is better,but not neccesary.Ditch the precat,it kills spool time and is not needed to pass smog testing.Dont worry about any piggybacks either,just run a FCD and a decent fuel pump (I run a SupraTT in the tank) and youll have enough fuel for 10psi,stock is 8psi.If you want to push past 10-11psi,then some bigger secondaries (680cc-720cc) should be installed along with a good boost controller.

neil Gueldner

iTrader: (1)

Thanks. I've read several of your posts. I'm planning to have a 12A front cover modded to use the S5 OMP like you did. If I can't get that to work, I'll premix and stick the OMP in the corner of the engine bay.

So do you think I can get 10psi using the 12A exhaust parts, or is that just too small? The Bonez cat and RB muffler flow better than stock 12A, but still probably well short of a turbo exhaust. I'm not going to run a pre-cat just a 2.5 DP.

steve84GS TII

A RB muffler will work fine and keeps it very quiet.
The SP version of the RB muffler and 3" Bonez cat works fine for my 14psi streetport engine,so I would be willing to bet the regular RB muffler would work fine for 10psi on a stock engine.
If you do get the SP version,its got a 2.5" inlet,which will jive perfectly with a 2.5" downpipe and Bonez cat.Just bolt up the downpipe,cat and muffler,then have an exhaust shop make up a 2.5" connector pipe from the cat outlet to the muffler inlet.Shouldnt cost too much,just do cheap crush bend,mild steel pipe.
Thats what I did with my old S4 setup and I hit 14psi all the time with it,...ran some 13.5's too.

FB II

word of advice, we have seen first hand here that the normal RB muffler is a massive restriction. i mean insane. if you are going to use a 1st gen rb muffler get the streetport version. (which honestly is what i think we had )

edit: by "here" i mean first hand, my friends turbo 12a setup we did. my car would walk his by buslengths until we took the rb off

steve84GS TII

The streetport version is for 81-82 cars with the stock dual midpipes.Its easy to spot since it has the same dual midpipes,except they merge into one 2.5" inlet right before the muffler,much bigger than stock.

I used this very muffler by chopping off the pipe right at the muffler and welding a 3" inlet to it to match my 3" system.The internal inlet pipe is just under 3" ID so its barely a restriction.....the reduction in sound is PHENOMINAL and it even passes CA noise standards.Any restriction penalty is small and I cant detect any change in power when I switch to my full 3" "loud" muffler......just a hell of a lot more noise.My old S4 setup had a full 2.5" system,it ran with no complaints and behaved similarly with the same boost levels,except on a stock engine and turbo....so a little less CFM's.

14psi out of my hybrid and streetport 13B for the last 4 years has proven to me the RB mufflers arent that restrictive.The regular ones light be a little,but probably not overly detrimental on a stock port,stock-ish boost level TII engine.If your worried about flow,but want a quiet muffler,get the RB streetport muffler.

Modified85

Man I sure am glad you guys are talking about this. My question is if you use a SE front cover cant you just use a omp from a 86? I was told that this setup would work with a after market haltech set up.

trochoid

iTrader: (6)

You can use the SE mop.

Rex4Life

I'd go with a 2-1/2 or 3" cat, custom catback with a Magnaflow (louder) or RB street port muffler (quieter).

The S4/S5 hi-flow cats will fit fine on your car. I used a stock replacement Corksport 3" downpipe-->Bonez turboflow cat. Don't use a 12a cat. Also for 200 hp 2-1/2" exhaust will be fine, but 1 year from now you'll be wanting 300 hp so just go with 3" exhaust.

The SE OMP will work but the S5 ECU will be expecting an electronic OMP. It should be possible to use an S4 ECU and wire harness and not have to worry about the OMP. This way you could also use a Rtek 1.7 chip for the S4 ECU and put 720's in for secondaries--this way you won't need a SAFC or FCD since they're built into the Rtek. Better yet just go with a Megasquirt ECU and not deal with any of that crap and it may be cheaper in the long run--but you better have some descent electronics and computer skills.

One of the biggest jobs will be the intercooler. Look at my thread to know more.

Depending upon where you live, this should be street/emissions legal. Mine just passed a few months ago.

HTH,

Scott

steve84GS TII

Running an SE or S4 OMP throws a monkey wrench into a S5 swap.

Yes,the S5 computor is looking for that OMP to be plugged in,it wont work without it.Yes,you can plug it in and tie it off to the side,thats been covered......I recommend premix oil when going this route because of this reason...........

The S5 throttle body does not have provisions to actuate a mechanical OMP.The pull arm is just not there.You cant add that arm either because it involves changing the linkage or throttle body to S4.If you change the linkage/throttle body to S4,then you no longer have to correct brackets to mount and actuate the S5 dual throttle position sensors.....which the S5 computor needs.

Your basically creating an ECU related problem(TPS) in order to get around an ECU related problem(OMP).Thats why I choose to just modify the SE front cover,run the S5 ECU and keep everything the way the factory intended.You can just run a S4 ECU and its specific sensors and mechancial OMP.Youll basically just have a full S4 swap,which isnt bad,its just not as good as the S5 and youll have to find all the puzzle pieces.
Of course this is all moot if you run a standalone,but some people want a factory ready ECU,and thats fine.You just have to adress the issues and be very carful not to **** the factory ECU off when you plan and execute your swap.

Modified85

Thanks for the above info.

estevan62274

iTrader: (32)

Hey Steve84GSTII, do you have any more info about an S5 water pump going on the GSL-SE front cover to allow for the turbo coolant line connection..... do it bolt right up?

steve84GS TII

The waterpump/water manifold assembely doesnt actually bolt to the front cover,it bolts to the front iron and kinda wraps around the front cover.I think I had to do a little grinding for clearance,no big deal though.
I run the S5 pump because I have to,in order to clear the bigger S5 OMP.If you run a mechancial OMP or premix,you can use either a S4 or S5 TII pump to get the turbo water hookup.
Dont forget the run the correct spacers under that assembely.They are off to the side and they account for the thickness of the base gasket,to keep the water manifold flat and sealed....

kenn_chan

Yeah, I did the tigged up front cover version, and it fixed all of the problems, If you (or your welder) is not sure steve sent me some photos that explained it quite well. simply tigging up the s-3 cover allowed the 2-5 mopp to be put on and all is well as a result.

kenn

mabii

In oder to use the s5 front cover dont you just have to make custom motor mounts?Because I plan on doing an s5 sawp and using the s5 front cover.

FB II

i'm gonna have to test this... we were using the streetport muffler as is with the dual pipes that collect, then lead to the muffler. it's a 2.5" pipe, but your saying it's almost 3" at the actual inlet base area? i run a 3" exhaust and would like to try this out, because one thing is for sure... it's INSANELY QUIET and my magnaflow (altho awesome sounding) is a bit noisy

steve84GS TII

I'd ditch the smaller midpipes for sure.
One big pipe will almost always outflow two small pipes,depends on the size difference but I think one 3" pipe outflows two 2.25" pipes.

gonzz

Someone needs to figure out how to trip the stock ECU on the electric OMP. Then we can use blockoff plates.. Can't be to hard right??

steve84GS TII

Im pretty sure its been done by some company.
The trick is the OMP puts out a variable signal,based on the position of the actuator v-s the postition of the TPS and the engine RPMs.If the OMP isnt putting out the right amount of oil,it will set off the limp mode.

Its not as simple as just,"Is it plugged in or not?" and, "Is it working or not?".
I think the eaiser method would be to just disable the limp mode that the ECU puts the engine into,then ignore the check engine codes that would indicate a faulty OMP stepper motor and postion sensor (or lack thereof) .......