1FooknTiteFD

I love teh sound of an open wastegate. I especially like the look of a stupid ricer or muscle car owner who sees your car, tries to race you and after you blow by them with that screaming wastegate the look on their faces is priceless

RX-Heven

iTrader: (1)

The vents on those that are essentially worthless in aiding cooling at all. The slots in the hood are located entirely in front of the radiator where they will not permit any airflow from the radiator to pass through or eliminate underhood pressure.

I have a vented hood where the vent is located in the correct position (above and behind the rad) and it dropped my on track temps by over 20 degress as compared to the TII hood. No other changes were made.
btw, I also run Evans coolant and it does much better under track conditions. You run it 0 pressure which has obvious advantages, especially with a rotary and you can get away with running the engine at a higher operating temperature than with water/coolant. That is what I have noticed at least, especially before my hood swap.

RX-Heven

iTrader: (1)

I clogged mine on track many years ago without an airpump. Felt like I had lost a rotor, but didn't sound like it. Didn't sound normal either. A quick fix with a broom handle and I missed only a session You should have seen the people laughing while I was doing it in the paddock. It was a stock cat and relatively stock setup with that car then (88 TII).

streetdreamzny

iTrader: (6)

just got my car back , here's another r85 pic

alberto_mg

Max, there was a thread in the 3rd gen section a while back where a guy added another muffler/resonator to the pipe just behind the cat/mp and before the standard muffler location. He said that it was an optimal location to cancel out the soundwaves or something to that effect. Might be worth a try to be able to run that track

maxcooper

streetdreamzny, looks good. I think Damian is getting close to finishing his install, too. With all these kits installed we should be getting some dyno numbers soon. I've got a dyno tuning session setup for April 29.

alberto_mg, I will look for that thread. We've got another thread going (resurrected and now active again) about quieting single turbo cars: https://www.rx7club.com/single-turbo-rx-7s-23/loud-exhaust-single-turbo-8710/

-Max

streetdreamzny

iTrader: (6)

thanks max, i hoping to dyno around april 22nd - just don't know if i'll have enough miles by than

allrotor93

iTrader: (126)

just put it on the dyno at 100 mph and hit the cruise

RX7UP

Sweet Set Up, Nof
You are gonna Kick some *** this Summer!
Congratulations!

TwinTurbo93

Congrats, looking good, that's a pretty huge turbo, how is the lag on it...?

I should be installing my RX6B soon, just polishing it and some other stuff...

maxcooper

I'm still breaking in an not really pushing the car, but the boost threshold is pretty reasonable. It starts to build a little boost down near, say, 2300 RPM if you are lugging the car in high gear (just like my stock turbos!). It builds slower than the stock turbos after that, but you get 5 psi by 3000 RPM and then it ramps up more aggressively from there. The 15psi kgparts.com dyno sheet seems to indicate full boost by 4250 RPM, and I think that is about where my boost peaks, too (not entirely sure, maybe I'll make a video). But even before that it feels pretty strong since you are building some boost. It isn't 0-0-0-0-0-15psi!, but rather it builds smoothly and you are already moving pretty fast when you hit full boost.

Two things I have noticed with running this larger-than-my-old-setups turbo:
- The car feels pretty decent before the boost comes on, perhaps due in part to the engine just making decent power unboosted / barely boosted up near the RPMs at which the boost comes on strong. I am quite pleased with how it feels around town.
- Boost comes back very fast after a shift, perhaps due in part to the fact that the turbo has more inertia than my previous, smaller turbo setups which might keep it spinning faster (maybe faster isn't the right word, but fast enough to outflow my old turbo the moment you finish the shift). I also moved my BOV from the turbo-to-IC pipe to the IC-to-TB pipe, which might help as well since there is less reversal of flow in the pipes for the compressed air to exit via the BOV on a shift.

-Max

TwinTurbo93

Max, are you planning to runn higher than 15 psi?


I think that is because you get more air flow even though when you're not boosting.

I admire your work, can't wait to see some dyno numbers.

maxcooper

I don't really plan to drive the car with more than 15 psi. I'll be using it on the street and circuit tracks with pump gas, so I think that is about the limit for me. The idea of getting some "dyno queen" numbers with more boost has some appeal, but I doubt I'll do that.

Thanks for the compliment. I can't wait to see how it works, too.

I did some more casual boost threshold testing today. Lugging it makes boost way down low, 2200 RPM or so, 5 psi by 2800-2900 RPM, 7 psi by 3200 RPM. Without lugging it (say third gear), it makes a few psi as it passes 3000 RPM, 10 psi by 4000 RPM or so, 15 psi at 4500 RPM. That probably sounds a lot laggier than it feels, though. You are hauling serious *** before it hits full boost. I'm running a HF cat and RB dual tip exhaust, so you might get even better spool with a more free-flowing exhaust. I'm also running thick oil and my car isn't really tuned, so don't take these numbers as "the answer" to the question of boost response on the R85. I am pleased with how it feels now, though, so even better would just be gravy for me.

-Max

LETHAL RX7

iTrader: (1)

seems like the lag of my modded t78. Its really not like it sounds bc after it makes the boost ill bet it keeps pulling all the way. right.
greg

TwinTurbo93

That doesn't sound laggy at all for a big *** turbo like that.
I'm planning also to push around 15-16 psi max with my new RX6 setup and h2o/alc. injection on pump gas.

GoodfellaFD3S

iTrader: (213)

All of this is very similar to my experience with my non-seq BNRs. Good info max, keep it coming

aREX4X

Any updates? Perhaps you got it tuned? I'm at the edge of my seat on this one, I really want know what this one does. I'm still trying to talk myself into this.

X...

maxcooper

My tuning session is scheduled for April 29. I will have dyno numbers after that.

The car is loud with the open wastegate. I think I only started to crack it a little before so I didn't get the full effect. But I have since then and it is louder than I want. I'm planning to get it plumbed back into the downpipe before the tuning session. I'm also having a midpipe with both a metallic cat and a muffler in it fabbed before the tuning session.

-Max

ghostrx7

Max you should plumb it back in AFTER the initial dyno..then dyno again with it plumbed in...just to see the difference in whp...imo.

aREX4X

Thanks for the reply, I'll keep my eyes on this thread.

X...

atihun

Damn man, you payin'?

Poweraxel

why would you do that?

maxcooper

I am curious about the power differences with the wastegate plumbing, but tuning is expensive and time consuming, so I only want to do it once with the final config that I will be using.

Noise and smell. I am fond of neither. Even with my special midpipe, it's still going to be loud and not particularly clean in the emissions department (but at least it won't smell).

-Max

ghostrx7

What I was suggesting is that you dyno tune with it open to atmosphere, then just redyno with it plumbed back in, basic standard dyno runs arent that expensive, usually 40-60 bucks around here...not sure how much they cost out there. Just a suggestion in case you wanted to record the difference in power levels between the two.

maxcooper

That would work. The expected change in power suggests a change in tune would be appropriate, however it probably isn't enough to be a problem. And tuning with it open first would just leave me a bit rich (pun alert! ) when all is said and done.

But my main problem is spare time. I don't have much (though I do get to escape and post-***** it up on the forum, since I can do that with no planning and stop as soon as I need to ). I just want to get the car done (if such a state is possible) and enjoy it. I've driven it less than 1000 miles since the middle of 2003, and haven't been to the track since December 2001.

-Max