DIY Turbo Discussion greddy on a 1.8? homebrew kit?

n00b here looking for advice for setup

Thread Tools
 
Search this Thread
 
Old 10-08-2007, 10:48 AM
  #1  
Newb
Thread Starter
 
JrodNJ's Avatar
 
Join Date: Oct 2007
Posts: 14
Total Cats: 0
Default n00b here looking for advice for setup

Hi everyone; my name is Jared. I'm on my 3rd Miata and have decided that this is the one to Turbocharge. My goal is to build something is reliable and driveable as a daily. I'd like to stay in the 6-8psi range and have a turbo that spools quickly. I'm not as concerned about top end or ultimate high HP numbers as I am about responsiveness and quick torque buildup.

I'm currently looking at the gt25/16g/k03 turbos.

It seems there is a kit on ebay that uses a 16g (or knockoff) for a rather cheapish seeming price. It looks like all I'd need are a bigger fuel pump, bigger injectors, and some sort of AFC to help things along.

I'd look to upgrade possibly later down the road and add an oil cooler for reliability purposes.

I'm looking to spend between 1300-1500 for parts for my intial setup (not counting any labor needed that I can't do).

I've been reading the FAQ, but a lot of it is lost on me because I'm totally new to this game. So there you have it; my introduction, my problem, and my plea for help.

Ebay kit - Crap or worthwhile?
Small 16g - Suitable for what I need? Manifolds are easy to find.
Remember - My goal is for smooth, reliable power that won't overwhelm the rest of the car at a cost effective price. I'll gladly take a proven reliable setup any day over a costlier, newer, potentially unproven "hot" setup.

Here is the mechanical side of my car

1990 Miata with 1992 Engine and Tranny

Suspension
-Adjustable Koni Struts
-Millen Lowering Springs
-Jackson Racing Swaybars and Endlinks
-Front Strut Tower Brace

Performance
-Conical Air Filter
-OBX Ceramic Coated Long Tube Header
-Flyin' Miata single Tip Exhaust
-Jackson Racing Plug Wires

Stopping Power
-2000 Miata Brakes (bigger)
-Hawk Pads
-Slotted Rotors in Front
-Slotted and Drilled Rotors in the Rear

Safety
-Hard Dog 4 Point Rollbar
-Simpson 5 Point Harness
JrodNJ is offline  
Old 10-08-2007, 11:12 AM
  #2  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,493
Total Cats: 4,080
Default

I'd stick with garrett products, as you'll find a bigger number of supporting components.

with that said, the sr20det t25 comes to mind. You can always find them for under $200.


If you really want to stay within that budget, you're looking at the bare minimum setup:

turbo / manifold / dp, no intercooler, 1.8L injectors, FMU, Bipes.
Braineack is offline  
Old 10-08-2007, 11:12 AM
  #3  
Newb
 
Gdbyrd's Avatar
 
Join Date: Oct 2007
Posts: 23
Total Cats: 2
Default

I too would be interested in knowing the answers to your questions. Sorry I can't help you out...new here myself. My experience in the past with car stuff is you usually get what you pay for...that's not to say it's a bad setup, but let's see what other people here have to say.
Gdbyrd is offline  
Old 10-08-2007, 11:17 AM
  #4  
Newb
 
mr2guy7's Avatar
 
Join Date: Dec 2006
Posts: 5
Total Cats: 0
Default

wow what a post...anyway with your goals and price range i would just go ahead and pick up a greddy turbo kit for like $1200 - that way you wont have to fabricate anything and there are tons of up grades to it now but if you think you are up for a diy the turbo for would either be a t25 or a t3 super 60 but youre lucky you have a 1.6 cause before you get a turbo you should pick up a megasquirt pnp because tuning is what is going to keep the setup reliable or not

Last edited by mr2guy7; 10-08-2007 at 11:36 AM.
mr2guy7 is offline  
Old 10-08-2007, 11:35 AM
  #5  
Boost Pope
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago. (The less-murder part.)
Posts: 33,027
Total Cats: 6,592
Default

I'll not comment directly on the eBay ChinaChargers as I don't have any personal experience, but some on this forum have observed or conjectured that the quality of the manifolds on these kits is poor.

Engine management however I will chime in on.

Using an AFC-type device for fuel control is the Wrong Way. With the Miata, there are three basic schools of thought on fuel.

There's the old-reliable adjustable FPR. With one of these units, plus perhaps a set of used tan-top injectors from a '94 to '97 Miata (they are *slightly* larger than the '90-'93 blue-tops) you will have sufficient fueling to run 6 to 8 PSI on most turbos. You may find it necessary to replace the fuel pump as well in this situation. Used units can sometimes be found around here, and consider adding a Bipes ACU to perform ignition retard.
Upside: Simple to install.
Downside: Not good above 6 or 8 PSI, doesn't address ignition timing.
Examples: The Bell Engineering model 2025 http://www.bellengineering.net/Pages...uelsystem.html


Then you have the piggybacks- eManage Ultimate and eManage Blue being the popular options. Both will control fuel and timing, giving you boost-referenced ignition retard and the ability to control larger injectors. The EMB (Blue) uses an AFC-like mechanism for injector control, so it is limited in the size of the injectors it can use- 330cc being a commonly accepted maximum for good idle and cruise. The Ultimate (EMU) intercepts and trims injector signals directly, so it can easily run 440cc to 550cc injectors. It will also allow you to remove your airflow meter.
Upside: Not terribly complex to install and tune.
Downside: The most expensive of the options.


Last are the full-replacement ECUs. Megasquirt is king here. Prices for a Megasquirt range from around US$250-$300 if you build it yourself in kit form, to $700 if you buy it fully assembled in true Plug-N-Play for (no wiring required at all).
Upside: The most versatile, and cheaper than a piggyback. MSPNP is also a wiring-free solution.
Downside: The most complex to tune.


You'll want a set of new (used) injectors for any of these. Stock 1.8 tan-tops go for $50 a set all the time. Larger injectors will range anywhere from $75 to $300 a set, depending on how resourceful you are. Used injectors from a non-turbo '89 to '92 RX-7 are a good find- 460cc, and a direct plug-n-play fit into the Miata harness and fuel rail.

A wideband O2 sensor if a good idea if you go with the AFPR, and pretty much a requirement if you do a piggyback or a MS. Plan on $200 to $300 here.
Joe Perez is offline  
Old 10-08-2007, 11:40 AM
  #6  
Elite Member
iTrader: (39)
 
Zabac's Avatar
 
Join Date: Sep 2007
Location: High Point NC
Posts: 4,850
Total Cats: 8
Default

cheap-fast-reliable: pick two!
in that $ range you should go with premade Greddy kit, or a complete DIY set-up
whats your location...if you are nearby i wouldnt mind helping you out...
take things slowly, do not take shortcuts, thats when **** hits the fan, one step at a time...since you are not aiming high, a t25 is all you need, cheap and reliable
Zabac is offline  
Old 10-08-2007, 06:03 PM
  #7  
Newb
Thread Starter
 
JrodNJ's Avatar
 
Join Date: Oct 2007
Posts: 14
Total Cats: 0
Default

I'm in NJ, but thanks for the offer of help. It looks like the forum is the way for you to best help me out.

I'm new to this so certainly exploring all options. I don't NEED to get everything at once and I don't NEED to have this project completed right away. I am anxious; but I'm trying to learn as much as I can on here. The FAQ is very helpful; but there's just sooooooo much information that it can get overwhelming.

I have a buddy that builds turbo setups and he has a few ideas for me. I'll find out what he's got in store and report back for the verdict from the experts.

Thanks
JrodNJ is offline  
Old 10-08-2007, 06:45 PM
  #8  
Elite Member
iTrader: (39)
 
Zabac's Avatar
 
Join Date: Sep 2007
Location: High Point NC
Posts: 4,850
Total Cats: 8
Default

if you are reading the FAQ's you are on the right path...
do not get too deep into subjects that concern you, only read things applicable to you and use plenty of common sense, thats where a lot of people are out...lol
are you friends with anyone that has and knows how to use a welder? if so, try to make as many of your things as you can
i am making my own manifold/DP/exhaust/intercooler piping/brackets/etc.
also, your local autoparts stores have a lot of the things you need
NAPA carries SS braided oil lines for fairly cheap, do your own research as far as what fittings you need and where you need to tap your oil return, etc. you can find all that by using the search function
when you are learning, take one thing at the time and just study it as far as what it does and why its important, the people here will not misslead you, so sometimes its important to just listen, lots of smart guys on here that know what they are doing, not me-i just listen to them...
you sound like you are an auto-x, responsiveness/driveability more important than high hp curves...way to go!!! lol
just take your time and dont take shortcuts unless someone has already done so and it is proven to work...i recommend megasquirt, but if its not permitted by your budget than just stick to quality bad-aids...be careful with used parts on ebay, classifieds here are much better source
too much more info, just read and dont be affraid to ask question...im not
Zabac is offline  
Old 10-09-2007, 11:05 PM
  #9  
Newb
Thread Starter
 
JrodNJ's Avatar
 
Join Date: Oct 2007
Posts: 14
Total Cats: 0
Default

I was speaking with some people tonight about this and one (who has a crazy high power turbo drift Miata) suggested that I won't require the Mega-Squirt to reliably achieve what I want.

Also; as far as injectors go - I was offered a set of 460cc injectors off a 91 RX-7. I believe my stock Injectors are 210cc. It was suggested to me that having such a LARGE injector could pose cold-start problems with the car and that I may be better off with a P&P injector in the 300cc range.

That said; don't Mazdas have an electronic fuel cut where if you floor the gas while starting it "chokes" the EFI system momentarily?
JrodNJ is offline  
Old 10-09-2007, 11:09 PM
  #10  
Newb
Thread Starter
 
JrodNJ's Avatar
 
Join Date: Oct 2007
Posts: 14
Total Cats: 0
Default

Also; with all due respect to my lousy luck and clumsy hands, am I doing myself a major dis-service looking at these "China-Charger" kits? Would I be better off going with a Greddy kit? While maybe not as "complete" they should feature better quality and not need so much fabrication to "make fit" right.
JrodNJ is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Full_Tilt_Boogie
Build Threads
84
04-12-2021 04:21 PM
Rick02R
WTB
3
01-03-2016 07:18 PM
chris101
Miata parts for sale/trade
2
10-09-2015 09:08 AM
mx592
Suspension, Brakes, Drivetrain
1
10-01-2015 12:45 AM
JesseTheNoob
DIY Turbo Discussion
15
09-30-2015 02:44 PM



Quick Reply: n00b here looking for advice for setup



All times are GMT -4. The time now is 07:50 AM.