^ That's a good point, though stock catback is 31 lbs. according to the gains per part added thread. But yeah, still heavy.

 

The extra 100-300hp you get from a basic single sure makes the car seem a whole lot lighter..

 

And thus proves AntiGravitys claim that going from a Lead-Acid to Li-Ion battery is probably the cheapest 25lbs of weight savings you can find (except if you stop eating)

 

I forgot about that stock battery.

Stock is a 34R and it weighs about 51 pounds.

Going to a 51R battery with one of the smaller battery trays is a good weight savings, 51r is about 25 pounds.

Anyhow this thread is drifting well off topic....

Here's a great resource if you are thinking about going single or looking at different options -

Banzai Racing FD Dyno Gallery

You can see the dyno charts and mods for each car. It's also interesting to see the actual plot of the dyno and not just peak numbers, here is where you can really see some of the older very laggy single turbo setups.

I've driven some big single cars back in the day, around town they are pretty weak, like driving a non-turbo FC under 3500 RPM - no grunt at all. Yes you do make a ton of power up top, but I want a ton of power EVERYWHERE, not just up top.

That's why the 8374 is so good, it will make all the power you want on this chassis but still spool up like the twins and be fun to drive around town.

Dale

 

It is interesting to look at the 35r dynos as back in the day that was considered a responsive turbo that made mid 400s when pushed. A ton of older FD owners on this site still running that setup. The 35r hits 300ftlbs around 42-4300rpms.... a full 1000 rpms later than the 8374. Its a night and day difference driving these setups back to back. Im still shocked at any single turbo FD owner making under 600rwhp that is still choosing to drive around without an EFR turbo.

 

Keeping the car in its respective state when you did the change over is the name of the game now. Everything is tuned as is and you start to learn the character of the vehicle.
Sure, if you want to continue fiddling with the setup, get the latest turbo. For sure you’ll spool sooner and harder than something that was installed over 2 decades ago. Such is the progress of tech.

However, I run the car for my enjoyment. No one else. I’ve gotten use to its response and it’s feedback. Does a 2700lb vehicle need 600hp for the street to be enjoyable?!?! I don’t know.. only you can answer that.
I personally don’t want to be fiddling with the car anymore. I just want to enjoy it. The thing makes about 400 as it is. That’s more than plenty for the street. It doesn’t make it all the way up top either. It starts to come on around 2600 and pulls like a freight train all the way till redline. I’m not sure if anyone really needs more than that. But hey, for the junkies who need to have the most, by all means. 600 is just a pinch a way.

 

Ive got some long time rotary die hard friends who said the same, until they drove an efr setup. The top end of an 8374 and 35r will be similar, the power under the curve and drive ability not so much. If you are happy, you are happy. I’ve had the convenience of driving about every turbo under the sun on a 2rotor under 71mms and the EFR is worth every dollar and headache it takes to convert. It really is the best of both worlds. I’m not a guy that chases big numbers, most of my fun is had under 100mph.

 

I had the same thought after driving Stephen's car last DGRR with the 8374. But my car is sorted, runs great, and is a ton of fun and I don't really drive it as much as I used to. Not worth dropping $4-5k on a turbo right now, especially when it really needs a paint job more than anything else.

But, if I had an older, laggy turbo that would be VERY VERY tempting.

Dale

 

T78 for the win haha. Do people around here even know what that is anymore?

 

^ I heard it's an hero.

 

It's lag in physical form

 

^^^ T78... Isn't that the newest Russian tank piloted by the latest Terminator.

 

Believe it or not, an old member of the forum still runs this turbo. He hasn’t visited in a very long time but yes, he still has his car and yes he still has the T78 in it. Lol

I remember driving his vehicle attempting to tune it. That turbo is hilarious. Nothing, nothing, nothing, boom! Hold onto your butt! ROFL. I think it finally started to deliver power around 4500-5500rpm. God forbid you were caught in the incorrect gear. Lol

 

We know the twins will out spool a single but would like to feel the difference.
Dale, It would be cool to do a quick 5-10mins, back to back comparison of our cars at DGRR this year.
You’d get a fresh experience of one right after the other comparison.
And we’ll post it up on the YouTubes 😎

 

I'd pay to see that on the YouTubes! And if I have boost control fully sorted out & tuned before then, I'd be happy to throw my FD into the back-to-back comparisons. Really curious to see how my BW S300-SXE setup with the external WG's stacks up against Steve's EFR 8374 setup with the IWG's and Dale's twins in terms of overall power delivery, spool-up, etc.

 

Yeah I think we have a plan! Let's do that!

Also BTW Pete Stephen and I will be coming up on Wednesday this year, we rented a baller cabin.

Dale

 

Shoot, whenever my restomod finishes (hopefully in 2022) I'd be happy to throw mine in the swapperoo comparison. It'll be an ewg 7670 with all the fixings you never knew you wanted.

 

If we are comparing stock twins to a single I would like to see a modern single tested that maxes out at same HP as stock twins.

I think a single like EFR 7163 0.80 or even 1.00ar T4 on right manifold will win on all levels.

Except, the single will feel like a dog on top end making the same peak power as the twins because the single made 100+ ftlbs more in the low rpm than the stock twins.

 

the EFR7163 0.80 A/R turbine housing would be substantially undersized on a 13B, like not even feasible turbine flow really. You have to understand while it’s a capable turbo, the smaller turbine wheel requires a substantially larger A/R to match the flow rate of the larger 7670 turbine impeller and it’s 0.92 and 1.05 housings.

just look at how far down the flow chart the 63mm 0.80 A/R housing is on the BW turbine housing list from BW Matchbot, well below where the 70mm turbine housings are. Some of which are not listed correctly. As per the other thread, the correct listing for the 7670 1.05 A/R is the blank line above the 70mm 0.92 listing; 25.5 lb/min peak flow.


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I’m working with a company now on a larger A/R turbine housing option for the EFR7163. I’m not even sure it will be large enough. Until then, imo it will have way too much emap to even consider.

 

Why are you guys trying to optimize such a small tiny turbo? I get that it's a problem to solve, but why solve it? What is the actual benefit to having all the power down low, when a rotaries strength lies in revs and its ability to breath up top. Seems like optimizing your gearing would be time better spent, quite a few companies will make you custom gear sets for not much more than the cost of an EFR. How instantly are you expecting to stab the throttle?

 

I personally went with the 7670 because most of my "enjoyment" driving happens on twisty back country roads. Too much power is wasted in this scenario due to traction limitations. Plus, my NA miata's have taught me that you can have a BUNCH of fun in a lower power car.

Granted, I also have an EFR 9174 and my system has been built to support well over 600whp. It'll be straight forward enough to have a map built for both turbos and to have piping/hard lines built for both. If I know I'll be driving in a different environment than I can swap turbos ahead of time and ensure the ECU is running the correct tune.

 

I understand the 7670 application, but a 71xx just seems tiny. The 76 seems to spool up as fast as anyone could reasonably use I don't see the argument for the 71.

 

Ah, I gotcha.

 

because 7163 compressor useable flow is the same as the 7670 compressor, but in the smaller and faster spooling B1 frame package. In my case the RX8 chassis has less space for a close-coupled low mount turbo and an EFR7670 is a much tougher fitment. So I’m familiar with and pursuing it from that angle on a Renesis turbo application, but it requires a turbine housing that isn’t going to choke out early.

with the new G-series Garrett being out it’s kind of a moot point now, though probably slightly faster spooling and I already have the 7163 in hand. A G30-660 would be a good low-mid 400 whp turbo in a very small, clean package though. I have a G30-770 for a pending 450-500 whp RX8-REW project.

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EFR7163 0.85 IWG left, G30-770 1.06 EWG right

7163 turbine housing is the largest they offer, you can see how much smaller it is, maybe about 19 lb/min off the top of my head vs 29 lb/min for the G30 twin scroll, and the 0.80 is another step smaller.



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