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-   -   best path to 300 hp on a n/a (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/best-path-300-hp-n-467022/)

Maxthe7man 10-03-05 08:02 PM

I played with one once killing time in Saitama.. Pretty neat and well beyond my means...
Going Ls-1 would defeat the purpose of trying to keep it lightweight, if ls-1 boy is gonna tell me an ls-1 weighs less than my p-port, he is on crack , plain and simple..


It's not so much injector timing that I am worried about, it's the much lower resolution of the Megasquirt when compared to other EMSs. Might be difficult to get idle and low throttle to act smoothly. Also, with PP I'll have to switch the load map from MAP based to Alpha-N (RPM and TPS) due to the weak and inconsistant vacuum signal.
yes reversion plays havoc, and its possible to have a 0 zero vac map signal with very different loads and air flows..Tps and RPm is the way, as charge pressure remains constant.
Why I am considering the motec is the map enhance feature that allows you to expand a point on the map to gain ultra fine control of the fueling at the points to overcome the nasty reversion of a p-port couple with using large injectors. So far I havent seen ecu map interpolation ever work that good, it always seems to cost a bit a power over being able to exactly tune that point, since almost no engine is exactly linear in its air consumption for a multitude of reasons..
I have been treated to seeing alot of ecu's run in comparison, and the better the resolution and control, the more power the engine will make when tuned properly..
I use to be a total haltech nut swinger, but that changed after seeing a motec and F-con in action....Max

NZConvertible 10-04-05 12:12 AM


Originally Posted by dDuB
What exactly do you mean by injector timing?

Injection timing is when during the engine cycle the injectors fire, basically the same concpet as ignition timing. On a stock engine with minimal overlap injection timing is not that critical. With the large overlap of a PP it is critical that it's set right. Aftermarket EFI lets you tune injection timing, stock obviously does not.


Originally Posted by banzaitoyota
anyone have slide throttle experience on a P-Port?

Mazdaspeed does (R26B). ;)

ddub 10-04-05 12:16 AM

Thanks for clearing that up :)

88IntegraLS 10-04-05 01:19 AM

Just thought I'd mention the possibility of bridgeporting and / or semi-peripheral porting. Take a TII block, add S5 NA rotors, custom build the intake manifold and exhuast with proper runner lengths, oil and stationary gear mods + internal clearancing for 9-10ishK rpm and feed it with an old weber.


Ah, I dunno. High HP NA doesn't look simple or cheap... I'd supercharge it, lol.

ddub 10-04-05 01:24 AM

^^^
:werd:

My engine/other projects ended up being expensive, and I'm just hoping for 220rwhp, more would be neat but I'm not gonna get my hopes up. Anywhere 210+ rwhp while I'm still fully n/a and I'll be perfectly happy.

Especially with my 10k RPM redline :D

88IntegraLS 10-04-05 01:29 AM

I just want 300 at the wheels and a cobra scream on top of the rotary blat, *delete this post* :)

Na is great when you're in the powerband. Ah who's being fooled, every engine is great when it's in its power band. Some just have it start a lot earlier in the rev range than others, bwahahaha

k1n0y 10-04-05 10:29 AM

I know you guys are all rotary fans damn i am tooz but you guys are so into rotarys you cant open your eyes to see how much power a v8 can make.

To let you know a ls1 is full aluminum... FULL! Its not lighter then a 13b PP but with the battier in the trunk it holds a 50-50 weight destrabution.

I know you can make 13bt pretty easily and cheaply over 300hp but have you ever driven a light weight car that handles like a dream and has low end torque?

go to a ls1 forum and see how much hp they get out of just header back and intake. Then look at dynos also with mild cams and springs and retainers.

my friend has a z28 that pushes over 450wrhp and he spent less then 2000 to get there...

Yes it's goin to cost a lot to do the swap and we all know that FC owners are cheap asses.

But I cant wait until next summer when my car bets the new c6 z06 on the straights and can out handle it as well.

Oh yah my car is goin to be CA smog legal!

RETed 10-04-05 10:40 AM


Originally Posted by k1n0y
I know you can make 13bt pretty easily and cheaply over 300hp but have you ever driven a light weight car that handles like a dream and has low end torque?

It's called a 20B.



my friend has a z28 that pushes over 450wrhp and he spent less then 2000 to get there...
Sure, but IS THIS TYPICAL?
No.
The Granny Speed shop "kit" costs that much, right?
How the hell you then pay for the engine and trans and custom driveshaft?

Come on, you should have enough sense to post shit like that in here - you know it's going to start up a big storm - it always does.


-Ted

kontakt 10-04-05 10:50 AM


Originally Posted by RETed
It's called a 20B.



Sure, but IS THIS TYPICAL?
No.
The Granny Speed shop "kit" costs that much, right?
How the hell you then pay for the engine and trans and custom driveshaft?

Come on, you should have enough sense to post shit like that in here - you know it's going to start up a big storm - it always does.


-Ted

Sorry Ted, but on the 20B it's called weight. The 20B throws the 50:50 off where the LS1 does not.


He's not comparing how much it costs to SWAP and MODIFY the LS1 into the FC, he's just saying that with engine-in-car it took his friend $2k to get to 450hp. If he was saying he thought he could get it in car and to 450hp on 2k then he might just be a case for retroactive abortion.

RETed 10-04-05 11:31 AM


Originally Posted by kontakt
Sorry Ted, but on the 20B it's called weight. The 20B throws the 50:50 off where the LS1 does not.

You haven't been in the 20B section recently huh...


-Ted

kontakt 10-04-05 11:49 AM


Originally Posted by RETed
You haven't been in the 20B section recently huh...


-Ted

Not recently, but it's what I'd gathered from reading before. I try not to read too many things about projects more than 10X my budget. Are they doing the swaps differently than before, or was I misinformed that it threw the balance off?

fcfanatic 10-04-05 11:56 AM

Doesn't an na 20b longblock weigh less than an fd longblock?

Thought I read that somewhere on here.

totallimmortal 10-04-05 12:06 PM

wow this thread is crazy whats up with a the pp talk anyway as far as most of us are concerned thats now a very streetable motor. for a streetable motoe i'd use some type of forced induction you'd be ably to reach that hp level much easier and cheaper. and for those of you talking about labor prices i'd assume the guy asking the quetions could not build a pp motor since he didn't even know what one was

banzaitoyota 10-04-05 02:43 PM

1 Attachment(s)
More air and fuel is all it takes, and the ability to injest and burn it. SIMPLE

Snrub 10-04-05 03:40 PM

So do we think the megasquirt is even viable for a PP?

I posted this PP concepts thread in the rotary performance section with some things that I was hoping to have clarified, but the thread isn't exactly setting the forum on fire. Perhaps you guys might take a look and give me your 2C? https://www.rx7club.com/rotary-car-performance-77/peripheral-port-semi-pp-concepts-questions-467762/

Really not the discussion I'd like to have in this thread, but:
The Renesis weighs in at ~275lbs whereas a LS1 weighs in at ~500lbs. A PP engine would be stripped down even further. I don't know that saying sub 200lbs is unreasonable. http://www.geocities.com/jeffguilfoi...neweights.html The suposed magical 50/50 number doesn't mean that a car truely is "perfectly balanced." From a performance perspective some rear bias is desired.

The thing is that you could probably get a 13BT to that kind of modded LS1 range for less than the cost of the LS1 swap. Yes the LS1 will be more potent at 1500rpm, but is that the primary motivation?

KoiHoshi 10-04-05 03:58 PM

Me = New to rotaries. Information here = Value x2 + new car / (this thread + knowledge - my stupidity) = Valuable information and good read.


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