slowredrx7

A freind of mine is rebuilding his supercharged 13b.It runs a 2.2l opcon autorotor supercharger.On 18 psi it makes 525hp @9-9200 rpmThis combination was put together many years agowith aless than ideal inlet manifold,a mazda carbie manifold on a series 4 turbo block.

was wondering with no other changes just a hi flow turb0 4 barrell manifold how much more power we could make.It may flow the same amount of air for a lower boost pressure therefore reduce drive power

any comments appreciated

SonicBlue

I'm obviously very late to comment on this, but I've always been interested in this idea, everyone I bring it up with says it's stupid, but I don't like the idea of turbo lag, I'd rather stay NA or go Supercharger, sorry I have no info for you guys though hahaha, let me know how it is

rx_214

18 psi @9-9200 rpm... seems to have too much stress on the engine in order to produce that amount of power output. (then again, I'm no expert to this)

Call Greg at Staff's Auto and ask him regarding the intake manifold, he will be able to help you out. Shop's info and contact is here: SA Motorsports | Winning races one triangle at a time!

It's not a stupid idea, just that supercharger is not as popular and more expensive compared to turbos, most people would turn down the idea of setting up a supercharger system in the 13B.

Here are more info about it: Rotary Tech Tips: Turbo & Supercharging

Personally, I'd want to do a turbocharger system in the idealistic world (except it's really hard to setup properly), where we have the supercharger providing boost at lower rpm, and a larger turbo that kicks in at around 4-5000rpm. It's similar to how 13B-REW's sequential turbo system.

SonicBlue

Yeah, I like that supercharger/turbocharger idea, and haha, I don't feel it's stupid at all, I've just always liked using the unique idea, everyone goes with either turbocharger or V8 swap, or both, it's so boring to see a V8 rx7, it's not why they were built! hahaha, and as for turbos, as much as I respect and love them, if I were to ever get one, I would want one that can engage very early

rx_214

I don't like the idea of V8 either... and as much as people say how it's more reliable and more power... it's just not what the car is actually made for. Not to mention how much it would cost to have a properly setup V8 system in the FC or FD, and you'll be dealing with a car that will likely be a headache with electrical or drivetrain all the time.

Then again, whatever makes you happy.

For a turbo that engage very early (or spools quickly), you would want to get a smaller turbo that runs at low boost. Quite frankly, a lot of people goes with such application for the 13B-T, where they upgrade the stock turbo to one with larger manifold and spins faster.

Pros with smaller turbo is that the boost engages earlier and faster, but dies out at higher rpm.

SonicBlue

hahaha i'm fine with power loss at higher rpm, that's just like an N/A, but what you said about the larger manifold, do you mean a larger exhaust side for spooling the turbo? I don't know much, but I kinda thought that a smaller exhaust side would create more of a vacuum to spool it quicker

rx_214

Haha, yeah... that's what I meant, a larger exhaust side to increase the flow. Thanks for the correction!

It would depend actually... I've been a N/A guy mostly, even though I have driven a few of my friend's turbo car before. But my knowledge and understanding with turbo is not that great... however, what you're mentioning has to do with the back pressure the exhaust is creating, which then goes into the design of the exhaust system, and we will be looking into both the inlet flow that drives the turbo, and the outlet flow the turbo pushes into the engine.

Bigger isn't always better, and smaller has its limitations, so it doesn't matter about the size of the turbo, or the amount of air/exhaust flow that goes in and out of the turbo, it's more so about finding what works best for your driving style.

slowredrx7

Quick update ,a new 4 barrell semi p port manifold has being bought.Will still be a couple of months away before completeThis engine was running motec efi cdiI Dont have a lot of time to be on here unfortunatley two of my detailed replys today wouldnt submit then lost. i will post more in the comeing days

SonicBlue

Haha, no worries man, can't wait to see more

RotorDad

Interested in seeing pics of this set up & more current output figures.

I fairly sure that the Mustang guys have seen 18psi with the 2.2 Autorotor.