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Vigilante Toyo Tech
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462 Posts
Discussion Starter #1
I recently bought a drag car (rollcaged 94tt) equipped with a gt47-88. I do enjoy going out and driving my cars on the street from time to time and to add more difficulty to the situation i cant get pump 100oct anywhere near by (i dont want to store it either)

If i run meth injection will it be enough on 93oct to drive it (aka run it hard when i feel like it)

I've heard that larger turbos like this have nasty boost creep when you try to run low boost settings and i am worried that the "boost creep" will push it out of the safe range of the 93oct and meth combined? Maybe not?

Will i have to retard my timing too?


Maybe i am just retarded and should get a smaller turbo or not drive on the street :(
 

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As long as your wastegate setup is good I think you'll be able to run low enough boost to be fine on 93 octane, I'd assume somewhere around 20psi would be fine. I'd get it all dialed out on the dyno because you are also going to run into timing issues. That thing should make some nasty power, even on pumpgas. I ca do in the 500s range with my lil 67 .92 a/r so I'd assume you are looking good with a turbo that big.
 

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Vigilante Toyo Tech
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462 Posts
Discussion Starter #3
20psi on an 88mm turbo on pump gas? That sounds really fricking high

By good wastegate setup do you mean i should get one of the dual wastegated t6 manifolds?
 

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Vigilante Toyo Tech
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462 Posts
Discussion Starter #5
Just buy my complete kit (instead of just the manifold) and run 15psi-36+psi.

Tim
haha


what do you have? search function is sucking balls right now.

-brad
 

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Vigilante Toyo Tech
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462 Posts
Discussion Starter #7
i just found it

I already have the turbo and ginormous intercooler setup... Dont want to spend another 5g's on another turbo setup

I WOULD like you to part with the manifold though :)

please!
 

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Premium Member
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5,991 Posts
I really don't understand having such a large turbo, and then only running pump gas and low boost on it. Even at 20psi, you won't even be close to that turbo's efficiency range. That'll be like 500whp Civic on street tires.... a ton of potential - wasted. :doh:
 

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Vigilante Toyo Tech
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462 Posts
Discussion Starter #9
I really don't understand having such a large turbo, and then only running pump gas and low boost on it. Even at 20psi, you won't even be close to that turbo's efficiency range. That'll be like 500whp Civic on street tires.... a ton of potential - wasted. :doh:


I know i know :(

But when i do want to drive it on the street i wanted to know want i could/would do with it.

Race gas will be saved for the track and dyno's, i just cant get the gas for it and store a 55gal drum of it in my garage.

-brad
 

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You mentioned 100 octane.. You're going to need more than that to push a 47-88 hard.. At LEAST C16, but most would probably recommend VP Import.

You can drive it around on pump gas, just don't get into boost unless you have a setup like basupra's where the boost will stay down. I wouldn't trust meth injection with a GT47.
 

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Moderator
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I know i know :(

But when i do want to drive it on the street i wanted to know want i could/would do with it.

Race gas will be saved for the track and dyno's, i just cant get the gas for it and store a 55gal drum of it in my garage.

-brad
you could, just make sure you stay out of boost. Of course, the day you're driving with no race gas is the day that everyone and their brother will want to race you...:sadwavey:
FWIW, I have a friend with an SP88 (old school T4 88mm) that drives it around on pump gas and wg boost that regularly hits 17-18lbs...he watches his boost gauge like a hawk, though...
 

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Vigilante Toyo Tech
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462 Posts
Discussion Starter #12
So i guess i am limited to storing the gas at my house.

Shits expensive too. $70 for 5gals. Guess i wont be driving it much.

-Brad
 

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Premium Member
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5,991 Posts
Well what it really comes down to is, with that turbo, if you're on race gas- it only starts to really be effective at 32psi+. If you're on pump gas, you're better off staying out of boost altogether. Like mentioned, even if you're watching that boost gauge like a hawk, you'll still be fighting boost creep.

So for you to be able to "run it hard when I feel like it" like you said safely, you need to be running race gas.


So, you could run that turbo on pump gas on the weekends, and put the race fuel in it for drags and big dyno numbers, but it sounds like you'd be better off with something smaller, that can be safely and EFFECTIVELY run on both pump and race gas, and equally as fun with both.

My 2psi on that... :)
 

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Vigilante Toyo Tech
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462 Posts
Discussion Starter #14
... you're better off staying out of boost altogether..

...you need to be running race gas...

... sounds like you'd be better off with something smaller...

The truth hurts Craig, and i knew it all along :(

I'm going to cry myself to sleep

-brad
 

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Bad RSP supra
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why not buy 55 gallon drums of 110 and get it tuned for that. u wont be able to boost a ton but its only like 4.50 a gallon.
 

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Unfvckwithable
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The truth hurts Craig, and i knew it all along :(

I'm going to cry myself to sleep

-brad
Bro, don't believe the hype. In order to run that size turbo and keep the boost down, then you are going to have to create a nice size vacuum leak. My recommendation would be to run two BOVs. Have one hooked up at all times, and when you want to reduce the boost that your turbo is going to achieve, then unplug one of them and voila. You have just caused a big enough vacuum leak that should take care of any creeping, of course the bigger the wastegate diameter, the more boost that would be bled off.

Important points:

1. Run the large diameter wastegate, i.e. HKS 60mm

2. Put the softest spring in the wastegate.

3. Have two BOVs hooked up, so that when you unplug one of them, you can still reduce the amount of air that would try to back pedal into your turbo.

4. Adjust BOV to be unplugged by loosing the screw to take away as much tension as possible.

This may sound like extreme conditions, but hey...

Hope this helps!!!

:)
 

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Alpha for president
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So i guess i am limited to storing the gas at my house.

Shits expensive too. $70 for 5gals. Guess i wont be driving it much.

-Brad

if you can afford the car...i'd say you can afford the fuel...
 

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Vigilante Toyo Tech
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462 Posts
Discussion Starter #19
i am selling them both
 

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WOW ill just say don't do it........... unless you don't want to run any boost and just drive around..... then run into some car that you just want to whoop its ass and cant cause you don't have the fuel.......... Or unless you want to ruin a motor..... My opinion cant make it happen with boost on that turbo and only 93 oct.
 
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