I just got my latest set-up tuned and couldn't be happier with the results. Tuning was done by Brian at Speed 1. He's a GREAT tuner - this my second tune from him. I highly recommend him.

Build details:

Lately, I've been looking for good power (>400 rwhp) and great response, but with a catalytic converter to reduce the smell. I decided to try a smaller turbo, but run it at higher boost with WI. I selected a Borg Warner S360 (BorgWarner S300SX 8375 Turbo S360 - Full-Race.com). It came with larger hot-side options so not to choke up top, was a direct drop in replacement with previous GT40R, and was very well priced.

For the converter I went with a Random Technologies direct fit cat (uses a 7000 series converter, very high flow).

I didn't want to deal with a WI pump, so I decided to go with Wannaspeed's per-turbo mechanical WI kit. I'm very happy with this kit all around (https://www.rx7club.com/auxiliary-in...-pics-1048812/). It performed flawlessly during the 20+ dyno pulls today and the 2 hour drive home. Some boost response was sacrificed, but not that much IMO.

The engine was built by Jim at JPR. I wanted good idle so he did a small street port on it (basically a polish). It has RA super seals. This was the third time this engine has been on the dyno in 1.5k miles and it's a rock. After each of the 60+ WOT pulls on the dyno, it just settles into a healthy idle pulling 17 in Hg. Jim builds great motors.

Overall I'm thrilled with how this setup performed. Out of all the different builds I've had (10+ years, 3 FDs: stock twins maxed out, A-Spec custom turbo, GT4088, GT4088R, and a GT3574), this takes the cake. Great response, and delivers power and torque right where it needs to (4k - 7k). The cat keeps smell down nicely. While it certainly chokes the top end power, it doesn't appear to have any negative impact in the areas I spend 90% of my driving in. The WI injection kept intake temps crazy low and the car felt great at 22 psi. The spool of the turbo is great considering the 1.0 hot side; hits 22 PSI by 4.4k rpm with the mechanical WI.

Dyno: 454 rwhp/ 381 ft lbs torque at 22 PSI. Has some wheel slippage between 5.5 and 6.0k. SAE corrected.



Quick pic of my car outside of Speed 1 in the snow... not to many FD snow pics out there .

 

Nice setup. I'll definitely consider it when going single. The cym looks great too. I'm from central jersey and can't wait for the road salt and snow to melt.

 

congrats on your recent dyno results and thanks for sharing...

i have an Excel file that contains 60 dyno runs, all corrected to SAE. since power under the curve rather than top tick wins races each entry has 6 power postings starting at 5000 rpm thru 7500 at 500 RPM intervals ordered in relation to the total of the 6 entries. all single turbo and of course all sorts of turbos, fuels, ports, and boost levels.

here's a quickly constructed chart showing your power curve compared to the other 60. since your dyno sheet shows results reported as STD correction i have adjusted your numbers to SAE. i didn't bother to tag the X line but "1" is 5000RPM, "2" is 5500 and so on to "6" which is 7500.

the "Y" index is % of your total power (2389) at the 6 plotpoints.

reading the chart, entry 1 is 5000 RPM. your results are Series 1 (blue) and it shows 12.8% of your total power (2389 SAE HP) at that level V the other 59 sheets at 12.1%. at 7500, probably due to your stock ports/cat you produce 17.2% V 18.8%

you appear to lose ground around 6500 (point 4) V the field.



i present this to you just as an FYI. pls do not think i am looking at this negatively. i really like everything about your setup from your turbo choice, your AI, even how nice your car looks.

in addition, you appear to have gotten exactly what you wanted since you are ahead of the curve as to power distribution for much of the curve especially in the mid range.

i suggest you get your car off the lake before the ice melts.

howard

 

Great info, thanks. Yeah, midrange the car pulls amazing and the cat seems to choke it above 6.7k rpms. Im not sure how the curve would look with a midpipe. I hardly notice it though, the car drives/feels great. This is by far my favorite setup to date.

 

Nice numbers especially through a cat. Open wastegate to atmos or re-routed?

 

Re-routed gate

 

Congrats! Very nice! I am using a BW turbo myself and am absolutely shocked at the unbelievably fat power curve and a journal bearing turbo to boot. Blows away my previous Garrett GT40 based turbo.

 

should you wish to construct an option to your cat i highly recommend (and run) a Borla 40944 muffler. all stainless steel including the sound deadening material, straight thru 3 inch, 16 inch body, well built & inexpensive.

IMO, lots better than a straight thru midpipe which attracts people in blue suits and eventually destroys brain cells. the 40944 sound is perfect w my RB catback.

swap your cat in for emissions if that's the way NJ works...

you will love it.

HC

 

I'm using a 3" vibrant ultra quite resonator with great results. Quiet idle and cruise with little to no drone causing at a freeway speeds. I can talk on my cell no problem while driving. I also have over 600WHP proving it flows great!

Vibrant Performance ::.

 

I swapped out a Pettit resonated midpipe. It flowed good and sounded the same as this cat... I just got tired of the smell. If I track the car, I'll probably swap out the cat. But for the street, I love it - the smell just got old for me.

 

Nice. I have a brand new mazda Cat for my FC and putting it back on. I myself cannot stand the smell after 20++++ years. LOL. back to PS, A/C and catalitic converter... Ya it kills the power but I can live with it.

 

wow clean, is that original yellow paint?

 

I'm honestly not sure... The paint looks ridiculously clean, no swirl marks, nice metallic depth, etc. The aftermarket hood matches really well, so I thought the whole car may have been sprayed when it was added, but there's no evidence of a re-spray. Car has 60k on the chassis, so its possible that it's just been taken care of well (I've had it for two years).

 

what manifold r u using?

 

It's a custom T4 mani that the previous owner acquired. I'm not sure who built it, but it looks very similar to the older style A-spec long runner manifolds. It may be slightly shorter. The turbo sits fairly high and far forward (hotside is in front of the LIM). Also, it uses a single tial 44 mm gate with 19 lbs of springs. Boost control has never been a problem with this mani.

 

did you play in the snow?! snow donuts!!!!

 

good numbers

 

That would have been a blast... But it was a loose gravel parking lot. Lots of rocks were kicking up just from me trying to get traction to get out of there.

 

Happy with Speed1's tuning?

 

Very happy with speed 1's tuning. I've had two tunes from both Dave and Brian and all 4 were solid.

 

Car looks awesome. Just to verify, it's the cat causing it to choke up top and not the turbo right?

 

I can't say for sure (I didn't run the setup with a midpipe), but I believe it's a contributing factor. I would think that a large street port, and a 3-4" straight exhaust would show much more top end power.

 

what catback are you running? Clean car btw

 

^ Thanks. It's an old school 1st gen RB dual. It has 3.5" tips and fits an FD much better than their new style. I'm not sure why they stopped making them.

 

mind throwing up some pics?