Just bolted on my SFR custom 3" HKS Carbon Ti true dual exhausts with my APS twins. Here are some impressions.

The piping of the SFR system is not fitting too well, especially around the M-brace area. Had to modify it a bit, and add a spacer on the M-brace to clear the SFR true dual so it wouldn't rattle against it. Slight hiccup, no big deal.

Here's the thing. The APS TT was bolted on, with my old JIC single exhaust and nothing else, and dynoed on a dynocom, which according to my tuner, has to multiply by around 13% to get normal dynojet numbers. So for the sakeof comparison, I will type out both numbers. Keep in mind I have a Rev-Up engine, so I might take mods slightly better.

Some of you might have noticed my post of the nice pink dyno chart before. That was my baseline...with Injen CAI and JIC single exhaust. https://my350z.com/forum/engine-and-drivetrain/155322-my-baseline-dyno-before-tt-rev-up.html

235rwhp 225lb/ft rwtq (dynocom)
= approximately 265.55rwhp 254.25lb/ft rwtq (dynojet)

After APS install, still with the JIC single and factory cats and y-pipe:

386rwhp 398lb/ft rwtq (dynocom)
= aproximately 436.2rwhp 449.74lb/ft rwtq (dynojet)

I was satisfied with those numbers already, and couldn't hope for better...until I bolted on the SFR true dual.

APS TT with SFR true dual without anything else. No tuning yet either:

430rwhp 404lb/ft rwtq (dynocom)
= approximately 486.7rwhp 456.5lb/ft rwtq (dynojet)

The baseline dyno some of you have seen already in the above mentioned thread. I do not have a dyno chart of the APS with JIC exhaust, but was told the numbers by my tuner. I do not have the dyno chart of the APS TT with SFR true dual yet. My tuner said he will send me that tomorrow. He just told me the numbers. Keep in mind my tuner HATED the SFR true dual cuz the piping needed some modifications to clear everything, but he was totally shocked with the results as much as I was.

The numbers above are all generated from dynocom, except the dynojets numbers which I calculated by multiplying the dynocom numbers by 1.13. Of course that is an approximate number. Not used to claim anything, but better as a comparison. That's why I posted all the numbers before and after the installs.

Tim (turbotim) at SFR was a pleasure to deal with. I was in need of a true dual in a hurry, he manufactured me one RIGHT AFTER I called and got it to me in a week. So the customer service is excellent.

This is a very well designed kit. Free flowing, reduces backpressure. Ideal for TT kits with huge amounts of tq, to tame down the tq a bit and increase top end power a lot by producing an exhaust with barely any backpressure. I'm thinking if the dyno came out like this, showing the lack of backpressure, I don't know if this would be a great exhaust of N/A applicatons. But for F/I, definitely.

Although I might add...the JIC may be better for N/A applications due to the backpressure. Too bad I didn't dyno both exhausts in N/A form as well.

I hope this answers some of the questions you may have about the new SFR kits that most of us are unfamiliar with. Just knowing it's with 2 HKS Carbon Ti's is not enough to purchase a whole exhaust system.

Feel free to comment on my analysis. I will post up the final dyno graph as soon as I get it from my tuner.

Here's a pic of the exhausts on my car. Sorry about the angle.



Here's a pic showing the APS turbo kit.



Feel free to comment. I apologize for the long read.

 

wow, 44hp from an exhaust. good choice! i spent several days at their shop getting my sc installed and watching them fabricate different parts. they are very good at what they do. it certainly helps that tim has a z of his own. he's a real horsepower addict, so his progress is ours.

 

for sure. Good luck with your SC Z boy. It's in good hands.

 

Very good numbers how much boost are you runing?

Az

 

stock boost. 8.5psi. Stock plenum, stock cats, stock block.

 

Great Numbers.

Question for you. In your opinion, should I go with the SFR 2.5" or 3.0" with my Vortech? I thought that with a SC, I would want a little more backpressure than with a TT, so going with a 2.5" would make more sense, correct?

 

2.5" would make more sense for N/A, but SC is still a form of F/I...I would think you would still be better going with the 3". I would call Tim directly and ask him. He would know the direct answer to your question.

Thanks.

 

Alex,


I am suprised you had to modify anything to fit the exhaust.It really takes two people to install it correctly with no modifications.One person holds the piping in place for clerance while the other one tightens down the clamps.It is best to fit the whole system on loosely and then work your way back.That is what we do here and we have excellent clearance.It takes a bit of work to get it right especially withthe slip fits since they alolow alot of play in the system but we have done several here at the shop as well as had quite a few customers install it with no issues.You also have to make sure that the pipes with the flanges that bolt to the cats are on the right sides otherwise it could cause a potential issue with the install.

 

Thanks Tim. Everything was done right, and they had 3 people doing the install...I wasn't there to see it personally, but all they did was modify the piping a bit, and place a small half inch spacer on the M-brace. Now it's totally fine. It was a bit of a hassle, but no big deal. And the gains...well they speak for themselves. Thanks again for everything Tim!

 

WoW Alex. Looks awesome. Can you get a pic straight from the rear. Awesome numbers. Again I dislike you big number FI guys

Congrats and enjoy. Now get some Vids...

 

I should get some more pics and vids today. I'll see what I can do.

Thanks for the compliments bro.

 

Hmmmmm.......I know Jotech,GRD and GT Motorsports have installed these systems and they have never gotten back to me with any sort of fitment issues so it makes me wonder.Is it something on our end or on your end?Anyways, you got it on and it sounds like it is working great.40 horsepower is pretty dang good for an exhaust.Now dont get too excited N/A guys because you wont see gains that big.Sorry.

 

How much is the 3" exhaust? You can pm me if you like.

 

here u go: http://www.speedforceracing.com/prod...g35exhaust.php

 

Is that with just a basic aps tt kit? Which map do you have installed in the unichip?

 

yes. APS TT full kit. It hasn't been tuned yet. so stock map. Tuning today for 93 octane.

 

Dam I was going to put on there plenum, but i guess I'll just have to save for a better exhaust.

 

Holy crap that's impressive with no tuning!! Nitrouz, are you going to get the APS 3.5" downpipes? It'd be interesting to see if they add any hp at 9lbs of boost.

 

the downpipes are part of the full kit already. It's on the car.

 

LOL. Yea, I know the kit comes with dp's but not 3.5" dp's. What size are the dp's included with the kit? If they're 3", I won't even bother buying the 3.5" ones, and I'll go ahead and buy the sfr exhaust instead of the aps one.

BTW I've had my APS TT kit for over 4 months but it's still in the box. I've decided to trade in my 05 ZR for a 06 GT coupe so I haven't installed it yet.

Oh, one more thing, does the SFR 3" exhaust come with 3" test pipes?