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DIY Turbo Discussion greddy on a 1.8? homebrew kit?

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Old 06-06-2008, 11:33 AM   #41
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IMO there is a difference between being a perfectionist and wasting money.
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Old 06-06-2008, 12:19 PM   #42
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I talked to Corkey Bell and he said 12 psi is very dependable on a stock 1.6.

I'm not trying to be an ***. Just hear me out. Some things don't go together.
Everything has a balance. You are going over kill on somethings, and way under on others.

The well maintained stock na motor last over 200,000 miles. The big parts don't give out, the rings do. It will be the same on your special built motor too.

You should call Corkey Bell and listen to the setup he advises. If you want it dependable for that hp goal. Just put a Greddy kit on your stock motor.
The extra you are thinking of spending would buy several used motors. Or a used Ls1 Camero.
And your probably not going to keep that car 15 yrs anyways.
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Old 06-06-2008, 12:22 PM   #43
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I just don't get this guy, I think he is missinformed about how a turbo set up works. Someone local take for a ride in a well set up car and have him come to senses, beat him if you have to, I just can't listen to him asking the wrong question over and over, but at the same time I want to help him, but he won't listen.

Low comp+high boost=the win
high compression+low boost=good
low compression+low boost=ok, still slow and inefficient
high compression+high boost=disaster/failure/kaboooooom

Before you waste more money, look into proper management, a built motor is worthless if you are not gonna make use of it, ie. low boost. Why? It makes no freaking sense.
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Old 06-06-2008, 01:02 PM   #44
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Quote:
Originally Posted by Braineack View Post
let's play a game: which one is the stock 01 at 9psi and which is the stock '93 at 12psi????
not a good comparison my friend. put up my #5 from the 08 dyno day and do it again. or the 006. or both i dunno.
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Old 06-06-2008, 01:44 PM   #45
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not a good comparison my friend. put up my #5 from the 08 dyno day and do it again. or the 006. or both i dunno.

actually yeah i should have used airbrushes, same turbo more or less....i did it in haste.
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Old 06-06-2008, 02:17 PM   #46
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no put mine! put my number 5 and 6 or I'll do it myself when I find your run!
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Old 06-06-2008, 02:20 PM   #47
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lolz.
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Old 06-06-2008, 09:03 PM   #48
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Quote:
Originally Posted by patsmx5 View Post
Hehe...

Alot is the answer. If you're unfamiliar search the forum for some threads on this subject.

On my 99 head I did some MAJOR unshrouding (not your typical unshrouding job), undercut valves, blended the bowls into the chambers and throat, reduced the short side radius, pollished the combustion chambers, removed any casting marks from the intake ports, and pollished the exhaust ports. When finished the car got so much more air that it was slower when I floored it because the stock ECU wasn't adding near enough fuel. Car would buck, backfire, and fall on its face. After Megasquirt it was ALOT quicker than stock.
Interesting. Do you have pix on the unshrouding? Where did you get the idea? Do you have flow numbers?
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Old 06-06-2008, 09:07 PM   #49
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Quote:
Originally Posted by Stealth97 View Post
..perhaps a GT28RS at 4-6 PSI,
I think this is backwards. For a street car, you want a smallish turbo that meets your power target, in order to get best response and low end.

Quote:
.. Off boost response should be great with the higher compression
Off boost torque gains from higher compression is 4% per point of compression ratio, but it doesn't help SPOOLUP. Turbo sizing is a huge factor in spoolup.

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and better head,
This will help spoolup AND off-boost torque.
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Old 06-07-2008, 01:17 AM   #50
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lolz.
lolz is the red and blue line up to 3600! heh
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Old 06-08-2008, 12:20 AM   #51
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This will make Zabac smile. I found the solution to my madness. Use stock engine, get new rings, get headwork done, upgrade to a standalone (Hydra) or parallel (MS) run like 12 psi, keep using my car as a work beater and get better fuel mileage than I do now cause I will have the power to properly tune it, and smile cause it's done.
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Old 06-09-2008, 09:00 PM   #52
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Very close. Only, why parallel? Do a stand alone MS. Cheaper, works better. Seriously.

Otherwise, you're right on.

As to the dyno pulls, the 1.8 liter is the one who didn't lift at 6k. :-)
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Old 06-10-2008, 10:50 AM   #53
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Quote:
Originally Posted by thirdgen View Post
This will make Zabac smile. I found the solution to my madness. Use stock engine, get new rings, get headwork done, upgrade to a standalone (Hydra) or parallel (MS) run like 12 psi, keep using my car as a work beater and get better fuel mileage than I do now cause I will have the power to properly tune it, and smile cause it's done.
:bowr ofl:
Amen brother...now you're talking!!! Proper management is key, the motor is very capable as is, your inability to tune it is what is holding you back right now.
At 12psi, don't waste your money on head work (unless you are doing it yourself and you know what you are doing), it will help, but at that power level there are better places to put your money. Head work becomes more important with bigger power goals as the benefits really start to show then, significantly.
If you will do anything to the motor (if you are planning a rebuild) just plan on some rods and rings and tri-coated stock pistons, you should be fine even at 300 whp then.
Good luck in your build...
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Old 06-10-2008, 02:41 PM   #54
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Headwork kinda always helps. With my wastegate full open, my car was as fast as a MSM, which I attribute to the headwork. 1 psi vs 8?

I think of it more as the gift that keeps on giving, the more you do the more good it does. 12 PSI on a modern motor is a healthy amount of power - hell, FM says you'll bend rods there, and to only run 9 (on their piggyback kit, admitedly)

But 225 whp on 12 psi is *entirely* reasonable, if not 250, on a '99 with headwork.
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Old 06-10-2008, 03:14 PM   #55
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Quote:
Originally Posted by AbeFM View Post
Headwork kinda always helps. With my wastegate full open, my car was as fast as a MSM, which I attribute to the headwork. 1 psi vs 8?

I think of it more as the gift that keeps on giving, the more you do the more good it does. 12 PSI on a modern motor is a healthy amount of power - hell, FM says you'll bend rods there, and to only run 9 (on their piggyback kit, admitedly)

But 225 whp on 12 psi is *entirely* reasonable, if not 250, on a '99 with headwork.
FM told me if I get the hydra to fun 12 psi. They said the voodoo won't control over a 1.8 injector, and could only run 9 psi.

Porting heads would be my last consern for your stated goals. You only need that if you are just going to race it out and have it undependable.
Having the head or even valve guides and seals redone for the engine rebuild may not be a bad idea.
You know your budget.
Good luck on the build.
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Old 06-10-2008, 04:05 PM   #56
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Quote:
Originally Posted by AbeFM View Post
Headwork kinda always helps. With my wastegate full open, my car was as fast as a MSM, which I attribute to the headwork. 1 psi vs 8?

I think of it more as the gift that keeps on giving, the more you do the more good it does. 12 PSI on a modern motor is a healthy amount of power - hell, FM says you'll bend rods there, and to only run 9 (on their piggyback kit, admitedly)

But 225 whp on 12 psi is *entirely* reasonable, if not 250, on a '99 with headwork.
Not dissagreeing there, just for his goals it seems unneccasary to do any head work simply due to the cost involved, that's why I said unless he was doing it himself, but if you are having a reputable builder doing any headwork, especially anything significant, it will cost a whole lot of money. Now if he was serious about making a lot of power then yeah, but then we are talking lots of other things to do as well.
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Old 06-10-2008, 05:05 PM   #57
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Yeah, ok, I'll give you that. It's a good thing to do (all about efficiency!) but on a budget, don't scrimp on engine management.
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Old 06-10-2008, 05:14 PM   #58
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I know all the magic of a better flowing head, for all serious power gains it's pretty much a must and it is the only part in my build where I'm willing to drop as much money as needed be to have everything of the best. That's why it's the last thing on my list.
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Old 06-10-2008, 05:48 PM   #59
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Better flowing head = more air for less pressure = less boost = less heat soak = less backpressure, etc etc. While you're in there, put in some real springs (wish I had! I still might swap them, it's a pretty quick job.), and get a higher redline. All free power! :-P

I guess I'm saying I'd do that long before forged pistons. If the motor's out, and you can get cheap rods, that might be the place to put money.


Forced Induction
EMU
Intercooler
Injectors
Free-flow exhaust (though this can be added later)
Rods
Headwork (below rods because it can be done later)
BOV
water injection
Bigger valves, etc, if cheap headwork first time
upgrade downpipe
upgrade intake mani
upgrade turbo
pistons
Boring/Stroking

Somewhere along the line where you're upgrading stuff, it's time to at least concider a motorswap. :-)

I'm curious what other people think about this list, as far as the order for things. Bang for buck, that is.
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Old 06-10-2008, 08:03 PM   #60
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I'd swap pistons with water injection. especially since you are going for "efficiency", forged piston while not only stronger (and not necessary for 250hp) are often lighter. That's weight at the end of your recipricating mass.
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