I have one of these A-Spec shorty manifolds for the FD. It seems like these shorty divided FD manifolds with twin ewgs are rarely if ever made anymore.

https://cimg5.ibsrv.net/gimg/www.rx7...708135f31a.png

it’s welded too, heaven forbid …

I’m not too worried about different or disagreeing opinions, others can do as they will.

some people think I’m always digging on Rob, but no. I was beating the drum loudly over the 3R, but when he’s putting a G35-1050 with a 1.21 Vband and calling it the best manifold ever made or a G40-900 on a choked-up, mostly stock T2, I’m going to point it out for what it is.

So congrats and hats off on making the changes that they did with the G40/T2 engine combo and showing the true potential. The response vs peak output difference of the 0.84 A/R housing in lieu of the 1.06 would be interesting to see. There are a number of things yet to be proven over certain differences of opinion. It will all eventually prove itself out one way or the other though.
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From the many plug reads I have done while tuning at the shop. Intake manifold is the biggest influencer of variance in fueling between rotors. I have also had many instances where the rotor with the Hotter EGT doesn't end up being the one that fails. Nor does it register as the hot rotor (on EGT) when doing a plug read.

A good back to back for me on this one was changing from an OEM FD intake to Typhoon, EGT's showed Rear rotor being hotter, Plugs showed Front rotor being hotter. I decided not to do any fuel trims and when we pushed that engine hard it was the front rotor that failed, not the rear.

Take from that what you will, but plugs has always been the most accurate form of data to do rotor trimming and intake seems to sway it more than anything else. Can't see I have ever changed an exhaust manifold and seen a change in the plug read as a result. Not saying it is not possible, just saying It's not something I have seen

pro engine builder with almost 50 years experience told me not to bother reading plugs on a rotary

of course he always recommended 11/11.5 plugs for racing and you can’t go any colder in the usual rotary selection …
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I guess we all have opinions. I didn't always read plugs. I could say that since I have started, it's definitely helped in reducing the amount of engine failures I have had for sure. It has also helped me identify tuning/coil issues during a dyno session before the issue becomes a much more catastrophic issue.

yeah that’s all I intended, everybody skins the cat their own way

but always appreciate your feedback, thanks for sharing.
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the future is closer than most people realize to avoid the generic vendor compromises and limitations:

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That's impressive that the printed stainless is pretty much at price point for bulk lot cast gear.

The printed is a very interesting option. Could create transitions and angles that proved impossible with welding methods.

Dang, I have been learning CAD for this exact purpose.

Had some printed parts quoted recently for another application and I was very surprised at how reasonable it was. Hopefully we see more of this in the future!!!

impressive

and some of us are already aware of this, but appropriate for this thread:


so he gave up making $1000/day building manifolds, to hawking t-shirts on youboob instead 🤔
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^^^ It's nicely made, but......wince each time I see what seems like every Nth American use angle grinders without cutting guards - to spread it on to the next youtube guy to copy cat. Fuck me, don't know anybody locally here who hasn't exploded a cutting disc or ten!

I like guards on my angle grinders but I've literally never exploded a cutting disc. I've chunked them sure, but I think exploding to the point where you'd be worried about shrapnel is probably more indicative of both improper use and shitty consumables used.

the same guy that 3D printed the inconel turbo manifold released another vid a week or two later for a 3D printed intake manifold. It will warm mr2peak’s heart to know he only put a Bosch 68mm DBW throttle body on it. It ended up as a shorter runner single piece rather than upper/lower 2 piece with a water-air intercooler welded in the middle of the plenum.

In the original video that started this particular series, he bought a 13B-REW from an FD3 that burned down in a fire for $950 on eBay. When he tore it down it was in near perfect condition with a beautiful street port, 12mm studs, lightened S4 8.5CR rotors etc. Luckiest find ever …
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I think there's that old axiom.......those who have, and those that will.....might apply eventually, even if not using alibaba spec discs. Some work places here won't even allow them on site due to frequency of injuries.

Why are you so antagonizing, yet you cry victim every time?

is that antagonizing, or me just referring back to our disagreement on that particular aspect of rotary engine tech as one man to another?

Which for those who didn’t see the thread, it goes back to the AU company Plazmaman stating that in their extensive intake manifold experience, a 70mm-74mm DBW single-plate throttle body is sufficient for 1000 hp on a reciprocating piston turbo engine. Which equates to ~700 - 750 rotary turbo engine hp relative to accepted mass flow rate difference between the two.

but just so we’re clear; I don’t consider your post questioning my intent to be antagonizing at all. Please always feel free to ask or say exactly what’s on your mind. Maybe you should go back and refer to the comments he made to me there even. Which I didn’t consider them antagonizing, but merely responded to the challenge with the facts as I understood them.

That being, there are many 13B turbo engines using 3” OD intercooler piping (~73mm ID @ 16 Ga thickness) and the total combined length/bends and resulting dP is going to be a lot greater than the 3” long 70-74mm ID TB with a milled shaft and plate in the center of it. It would also be fairly simple to measure the dP across the inlet to outlet as well rather than play the internet forum supposition game.

I’m also not a victim, but pointed out the hypocrisy for the off topic statements he pursued about my personal beliefs and commitments.
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