My new project

[Sideways s12]

I'm going to be ordering some cp pistons I asked for some input in another thread and all but one said go with cp so cp it is....

[Sideways s12]

well my tax money should be here the 13th according to the IRS so the motor will be going into the shop for a rebuild got some evo 580's Im going to be running just looking for a bigger turbo to play with I swapped the stock fpr for the sr unit and installed my 255lph fuel pump. I need to install my mishimoto rad and efans....also need to order a fpr gauge and going to swap my safc from my other car into this one along with my n60 maf. I have a new harnes on the way as well to take care of the rats nest I have in the bay.

[float_6969]

Dude, I love the new sig! Now I REALLY want an S12, LOL.

[Sideways s12]

Lol thanks yeah I thought it was about time to change it....

[Sideways s12]

Welp the motor went to the shop couple days ago so just waiting on that get to get done....

[Sideways s12]

Also going with the precision 5252E turbo seems like the best bet with the set-up I'm going with....

[float_6969]

You should be happy with it. There was another guy on here for a while who swore by Precision turbo's.

[Sideways s12]

Awesome I hope so....

[Sideways s12]

I need to know if swapping to the sr fpr is a good enough upgrade for the fpr I just need to find a gauge tho I was looking on ebay but all I keep finding is the knock off fprs...

[float_6969]

Do you mean new, or used?

[Sideways s12]

used I got an sr for free (needs alot of work) and I was told the sr fpr would be a good upgrade and since I had one and it was free I figured I'd save a little money and use it...

[Sideways s12]

Woot my cams came in today....

[Sideways s12]

So anybody know if the sr fpr is ok to use?

[Sideways s12]

Anybody?

[float_6969]

I've never heard of it being done. My concern would be that the the SR runs about 45 psi of base fuel pressure and the CA runs 36 psi. This would cause some minor over fueling, but not enough that the ECU couldn't compensate in closed loop. IDK if the CA has long term fuel trims. If it does, then would wouldn't need any thing else done except to let it idle for a few minutes to let it figure itself out. If it doesn't have LTFT's (I don't think it does BTW), then you'll have to do some tuning as the stock tune is already way too rich.

[Sideways s12]

Whats ltft? And i was going to hook up my safc to do some light tuning. If i get this spare ecu i was going to nistune it. I plan on running 560's with the precision 5252e with the .48 ar housing.....

[Sideways s12]

Picked up a cage for my beast....

[float_6969]

ltft = long term fuel trim. If the O2 sensor has to add/subtract more fuel than it thinks it should during closed loop, it will add/subtract that amount of fuel from the overall amount of fuel injected, even when it open loop. Like I said though, I don't know if the CA ECU is even capable of that.

The cage looks great though!

[Sideways s12]

Ahh ok I see what your saying.... Thanks....

[Sideways s12]

So i just went with a stock.rebuild and it turns out that the number 4 cyl was messed up so I need some.over sized pistons lol theres goes my money for.my turbo I guess ill be looking for a t28 after i get the motor back.....

[float_6969]

That sucks, sorry to hear that!

[Sideways s12]

Meh s*** happens lol...

[float_6969]

I like your attitude about it. I hate to see that happen and they scrap the whole project.

[Sideways s12]

Lol i love this motor and my car too much to scrap the project I had my first taste of the ca and i want more lol just wish i coulda got the precision but that later down the road and t28 it's a good substitute for now...

[float_6969]

You'll be happy with the T28. It's a great turbo for the CA. sometimes I miss the responsiveness it has.

[Sideways s12]

What are you running?

[float_6969]

An OLD HKS T4 turbo kit. T04E compressor, O-trim turbine. I changed the .48 single scroll turbine housing out fir a .50 A/R twin scroll housing. The manifold is a cast iron divided like the stock manifold, but it's a top mount T4 flange with an external waste gate.

[Sideways s12]

Nice where did you find the manifold? Whats the difference and benefits between twin scroll and single scroll?

[float_6969]

I got it from Themadscientist. I had been after one for years, but they're VERY hard to get a hold of. I had told him if he ever decided to sell, I'd buy, and when his motor popped, I picked it up.

It's not really a twin scroll manifold so much as a paired manifold. A paired manifold connects exhaust ports together that don't interfere with each other, thereby reducing the risk of exhaust back flow into the cylinders. On a typical I4 cylinders 1&4 and 2&3 are paired. This can be seen on most long length headers. In a turbocharged vehicle, the use a twin scroll turbine housing, mated to a paired runner manifold can further help to reduce any chance of reversion. The pro's of a setup like this are that for a given A/R, the turbo will usually spool faster, have faster response, but may loose some top end power due to the smaller ports for a given A/R in a twin scroll manifold (the area is the same, but divided in half). What is more typically done is that a larger A/R housing is fitted. Depending on how much larger, the turbo may still spool faster and have better top end power. The con to all of this is cost and complexity.

This whole concept is the reason I push people to keep their stock manifolds. The stock manifold is a paired design. One of the first things I did to my CA was to put a tubular manifold on it and it KILLED the bottom end power and responsiveness of the motor. I did gain some top end power, but overall, I felt like the car was slower.

[Sideways s12]

So basically twin scroll allows you to use a larger turbo that the motor would not beable to spool without a lot of lag? I totally understand what your talking about with the stock manifold vs a tubular I had a tubular break on my so I got the stock mani from a friend and totally felt the difference in the bottomend right away. My ca came with the tubular so I figured stock was just to restrictive. Now what if someone was to extrude hone the stock mani for better flow you think it would effect the bottmend any or you think its not worth it?