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MPM 04-08-04 07:24 AM


Originally posted by RETed
Okay, and this is my beef with this thread...

Just because the original poster made everything for $300 doesn't mean you can too.

REPEAT.

You are talking about an eBay purchase.  I won't even go into a possible bad transaction that involves faulty or bad merchandise - if you haven't been through one, it's one of the most frustratings things in life.  This means prices will vary; unless someone can show me a site where you can buy these used SC's for a set guaranteed price, the initial purchase of the SC is variable.

The SC and pulley bracket system has to be made out of very strong or very thick materials.  Precision has to be done down to under 1/8" (for the pulley), or else it's going to eat belts like a mofo.  I would estimate a typical machine shop would charge anywhere from $100 to $300 for this work.  Unless you got the resources and can weld like the original poster (which I think most of you cannot do), you not going to get a "free" bracketing system.

Although the poster did not run into any problems with the stock fuel system, upgrading is is highly recommended.  The stock fuel injectors can barely support 200hp at the wheels; I think you will be getting very close to this power level.  The stock NA fuel pump can support slightly more (maybe up to 250hp), but it's always safer to upgrade to a Walbro which will give you way-more-than-enough capacity from the fuel pump...at about $100, it's no excuse.  This means upgrade fuel injectors and the upgrade fuel pump costs need to be factored in.  FC turbo fuel injectors are pretty cheap and easily available, and I've seen prices anywhere from $50 to $150 for a set of 4.

A boost-dependent FPR would be a good thing, and the easy path would be to to swap for a stock FC turbo FPR (or entire fuel rail).  Retrofit BDFPR's are still over $100+ for a brand new one.

Now, as for the SC sizing...  Running something off a 3.0 liter 6-cylinder piston motor is just about perfect.  When we size turbos, we use the equivalent 2.5 liter to 3.0 liter piston engine displacement figures for application to the 13B.  Good job!

NZConvertible is right about the exhaust.  Running a stock NA exhaust will choke performance.  Although not required, it is highly recommended to run a freer-flowing exhaust system.  You might be able to get away with the stock exhaust manifold, but a mid-pipe, high-flow cat / test pipe, and aftermarket cat-back should be installed.  This is even more money to throw at this project.

A fuel computer is highly recommended to fine tune the fuel delivery.  Even used units are over $100, but many are already running them on their NA's.  If you don't have one, you should budget for one.  Ignition timing you can fudge with moving the CAS; if you need to retard it a little, just dial te CAS back a few degrees.  A retard box, brand new, is serious money.

Do you think your stock NA clutch can handle the increased torque?  I highly doubt it.  A new or upgrade clutch may be able to hold, but if you're running a stock OEM clutch that has a lot of miles on it, you're going to be buying a new clutch, guaranteed.  That's another couple hundred for the clutch!

I can go into a whole bunch of other things that can give you trouble, but this is going to end up being an epic, so I'll stop here. :)

In the end, I tally the final cost to be MINIMUM about $1,000 for a "typical" install.

If you have a highly modified NA with upgrade clutch + AFC, it's still about $700 minimum.

If you're starting with a car that's bone stock and high mileage, we're talking prices approaching closer to $2,000!

Bottom line, there's a LOT of auxuliary things you need to budget for and getting a "$300" SC off of eBay is just the start of your upgrades.  Don't look foolish and thing you can get your car running reliably with just a $300 SC...


-Ted

Wow Ted. Thanks for adding such negative vibes to such a positive thread. Always got to bring the little man down? I don't think so. Its seems if we don't do it your way we're doing it wrong.

banzaitoyota 04-08-04 07:35 AM

I think TED (Who I dont always agree with) is interjecting a BADLY NEEDED dose of reality to this thread.

patman 04-08-04 08:28 AM

I think all you people arguing on here should quit. This is a good thread about a great idea. leave it at that. I posted a long time ago, saying that this is really only good if you are a do-it-yourself kinda person who can figure it all out and make everything work without buying a bunch of shit. And basically, thats what it comes down to. If youre zbrown, or someone else with the skills to do this, then its a great mod, with a very good bang-for-the-buck value. however, if youre not so good, and youre going out on a limb to do it, then its not a real great idea. which is basically what Ted is saying. If you really know what youre doing, then what do you care what he (or anyone else) says...you just do it. But if youre kinda fuzzy, maybe you should listen to him, cause if you hafta ask, then he's right, this will cost you more than its worth.

pat

DCRotor 04-08-04 08:50 AM

the other persome did not post it so im trying to post.

fong 04-08-04 09:06 AM

I will take Ted's comments as a wake up call: think more before start the project. it is good to see things in different angles.

at first, I was so excited about the idea, and it is so attempting to be the second one to do it. well, what I learn from Ted is that we should face the reality. $300 is just a start. if we want our toys run better, we need more funding. and it could end up the same cost for a turbo swap.....

it is really up to us to think about what to do.

but my comment about this work: GREAT idea, way to go.

DEZERTE 04-08-04 09:29 AM


Originally posted by MPM
Wow Ted. Thanks for adding such negative vibes to such a positive thread. Always got to bring the little man down? I don't think so. Its seems if we don't do it your way we're doing it wrong.
Although it was somewhat more "negative" than positive, i dont think he was trying to bring anybody down. He's pretty smart and was just giving his 2c's

greenchili 04-08-04 10:51 AM

that BOV sounds GREAT!

the clip was really neat!

zbrown, you're doing an AWESOME job....KEEP UP THE GOOD WORK MY MAN!

:rock: :rock: :rock:

Chimeron 04-08-04 11:06 AM

Ted is right that people who don't know what's going on shouldn't do this. I'd like to do this but I DEFINITELY need to understand more to do it. That's pretty much the whole point of this thread. So that people can learn. That's also WHY I'm asking questions. Once I understand it all (hah, right) I'll do it.

banzaitoyota 04-08-04 11:50 AM

Here it is in another light: I have a well equipped shop w/paint equipment. I can put a nice paintjob on my car for 400-600$$$. Does that mean someone wiht a basic wrench set can duplicate my results for the same amount of $$, NO F'ing way!!!!

Be realistic in your assesments of your capabilities, skills and access to specialized tools when starting on a project.

MPM 04-08-04 12:36 PM


Originally posted by DEZERTE
Although it was somewhat more "negative" than positive, i dont think he was trying to bring anybody down. He's pretty smart and was just giving his 2c's
Any time your negative about what someone has done and inject your own opinions you bring someone down. Yes, what ted said needed to be said as some of it will hold true but the delivery needs worked on.

Hats off to zbrown for getting it working. Now continue improving upon it and keep us posted.

Visago 04-08-04 02:21 PM

hey Z, would it possible to get a launch or a 1/4 mile vid, that would be awesome to see it tearing down the strip:rock:

Aaron Cake 04-08-04 03:40 PM

OK. I'm going to delete all irrevelant replies from this thread, then move it to the archive as soon as it looks like it's over. Please save me the work and don't pollute this thread. This means no discussions about nitrous, who's right and who's wrong, arguments, etc. Thanks.

monkey 04-08-04 05:46 PM

Zbrown, i have a question. At about 6 seconds into the video clip it sounds like the engine bogs a for a second.(other than that it sounds great!) I was wondering if your axillary ports are wired open and if you've done the "throttlebody mod" or any other thing that may cause this bog at low rpms. I think you did a great job and im gunna try and pull this off considering i have access to all the parts/tools/sc. Thanks for any info

skydivr73 04-08-04 06:13 PM

so basically, what we have here is a way that somewhere in the ballpark of a thousand bucks and some work can get an NA owner into the power range of a TII....I fail to see how this is a bad thing. I look at the kits out these days as a joke. Even the new Atkins kit--over $3K I think it was, and for something like FIFTY HP...what a waste. Not to mention--there is no way that you can do a TII conversion for that price.

I would like to see a larger diameter intake size though...I am wondering how much that small setup takes away from the potential. And I am interested in knowing what other mods are recommended for this--like what kind of clutch and exhaust for example. The clutch in particular, since I need to replace mine soon anyway and would just go for the upgrade one now. What is a good streetable clutch for this kind of power? Keep in mind that the car will be a daily driver.

oh, and good job Z for getting this figured out this much. Keep working on it and let us know what you find. Also--have you considered doing anything like a kit to help others that want to use the same sc? Basically I am referring to the welded parts that many of us do not have a way to make. You could put together a set of mounting brackets, pulley and idler pulley, and maybe the adapter piece to hook up to intake piping. You would sell them pretty well if the quality and price were good. I dont know how comfortable you are with your welding skills, but it does look pretty solid in the pics.

NZConvertible 04-08-04 06:56 PM


Originally posted by MPM
Any time your negative about what someone has done and inject your own opinions you bring someone down.
Dude, this is a technical discussion forum. If everyone just blew smoke up his ass this thread would be utterly useless. And we don't all have the time to sugercoat everything we say just in case we upset over-sensitive people. Harden up and learn from Ted's advice.

FC3S-NovaStyle 04-08-04 07:05 PM

after seeing the vid i truely belive it's workable.. and DCRotor thanx for the precise picture of the adaptor, i'll have my friend start fabricate up one

FDreaming 04-08-04 07:39 PM

This is awesome! I'm watching a M90 on Ebay right now. Can we get some dyno runs, or maybe even a vid of it at the track? Anyone wanna start mas producing the plates required to bolt that Eaton on there?

White_FC 04-08-04 08:12 PM


Originally posted by DEZERTE
Hes running a bypass valve to recycle the excess air back into the intake but it doesnt relieve enough of the pressure, hence the Blow off Valve.
Interesting and overly complex twin BOV setup... But ok.. Thats fair enough.. :)

I actually wouldn't mind running a supercharged 13b one day.. If only M90's wern't so expensive over here..

Sorry if i've missed this but im sure as shit not going back through 13 pages to find it..
Does the boost drop off at/near redline or not? (I saw the rough calcs people have been doing.. im asking if it actually does or not.. :) )

chris406 04-08-04 11:16 PM

that sounded good

DCRotor 04-09-04 08:34 AM

well im trying to post the second pic of the bracket that back of the SC to the air filter. but it wont post ( says i posted it already) anyways i need more info from someone that has a SC i need all the bolt hole sizes and i need the length from the rear mounting bolts to the front one.

-B-

RETed 04-09-04 09:05 AM

I'm sorry if I have insulted anyone - it was not my intention to do so.

I submitted my comments to prevent people from killing their engines and cars.  We don't need more FC's to blow-up due to projects that are over their owners heads.

There is "proper", and there is "cheap".  I tend to over-engineer things and don't like to go "getto".  Yes, you can get away with cheaper, but it's all going to bite you in the ass in the long run.

I've been toying with turbo'd Honda's probably before many of you have been born.  It's a similar application when running this SC on your NA, as the tricks to getting enough fuel into the engine for forced induction use is similar; this is why I brought up the BDFPR.  I would also question what happens to the pressure sensor when you do go into boost.  With the Hondas, this triggers the CHECK ENGINE light, but I think the stock FC NA pressure sensor clamps output if it does go into positive pressure.  This is good and bad - no worries about a CE light, but we don't know if the stock ignition timing is okay with the boosted engine.  So far, the original poster's experience has been positive, so you might be able to get away with it.  It might be a good idea to dial back the CAS a little just for safety...


-Ted

wozzoom 04-09-04 10:11 AM

Ted - I'm with you. Its funny how people jump on you when you are in fact just trying to inject a dose of reality and keep them from blowing there engines. BTW: Your experience and input is always appreciated.

There is always a right way and a wrong way to do things. I'm not saying that zBrown did something the wrong way, but I would say that his car is a PROTOTYPE! I commend zBrown for taking the initiative on this project but from the looks of things, there is a lot of room for improvement. This is where the power of the list comes in…people need to follow in zBrown’s footsteps and find ways to improve the design. We’ll post our findings, evolve, and eventually come up with the requirements for bulletproof design.

From my observations there are several things that I would love to know about this project:

1) Intake temps. Does this thing need an intercooler?
2) How does the NA boost sensor react to pressure? Maybe Mr. Cake can provide us some input on this?
3) Does the SC pulley slip with such a thin belt? It takes up to 50 HP to turn an Eaton M90 up to 14,000 RPM!!!
4) What are some sources for pullies and idlers from other junk-yard cars?

Aaron Cake 04-09-04 10:32 AM

To be honest, I have not done any formal testing on the NA boost sensor. All I can say that from my experience, it works under positive pressure...

I have a spare boost sensor around, and if I get time today I will put both vacuum and positive pressure to it and post the output. I can suck down a pretty good vacuum, but can only do about 1PSI with my mouth. Sadly, I don't have another suitable source of pressure....I'll also be spending all day making an intake manifold from scratch, so I may not have time...

I think Bambam7 has done some testing, so let me see if I can locate the thread..............

Found it: https://www.rx7club.com/showthread.p...hreadid=262629

Basically said what Ted said previously: at atmospheric, the sensor is outputting 5V (it's ref voltage). Any higher readings will still result in a 5V reading. So the NA ECU knows nothing of boost...

That said, I did run 8-12 PSI on stock timing without any apparent problems. When I tore the engine down, no pitting was evident on the apex seals.

Zer0 Cylinder 04-09-04 10:42 AM

hmmmmm 5 pages later.......is the discussion still about getting enough fuel?

DEZERTE 04-09-04 10:43 AM


Originally posted by Aaron Cake
I can suck down a pretty good vacuum, but can only do about 1PSI with my mouth.
Lol.


Originally posted by RETed
It might be a good idea to dial back the CAS a little just for safety...


-Ted

What is the CAS? I looked and found it in the FAQ, but I don't know what it does.


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