teachermechanic

iTrader: (4)

I have in my 13B Garrett 62-1
.70 compressor
.96 turbine housing
Now i want to put this turbo on my 20B.
Is to small .96 turbine size for stock or street port?
I also have choice 1.32 turbine is to big?
Thanks

94RHDFD

iTrader: (3)

.96 for stock motor is fine but is too small for a streetport'd 20b, the 1.32 on a stock motor will have boost come on around 3200 - 3500 rpms

teachermechanic

iTrader: (4)

Thanks
1.15 is better choice for small street or stock port?

$150FC

I don't think the 62-1 wheel will flow enough for a 20B, will it?

94RHDFD

iTrader: (3)

On a stock motor it should spool quite nicely I think but with ANY porting the turbo will flatline

Turbo 3

iTrader: (3)

So...when will the 1.32 come on boost with a 20B streetported motor? 2000-2500?

Turbo 3

iTrader: (3)

Oops, I quoted the wrong person... 20B 3rd gen, that question is to you kind sir

94RHDFD

iTrader: (3)

Well on Red-RX7's car he has a T66 with a 1.32 A/R on a streetport'd 20b and he make full boost around 2800rpms I think

Red-Rx7

T72, "Q" Trim, 1.32 AR, 4" DP - MP - Catback, 46MM Wastegate; Dual Ball Bearing. Nicely ported engine.

I can build 26 PSI by 2800 RPM's.

94RHDFD

iTrader: (3)

That's right Mike you have the T72 I was thinking of Derrick's (www.3rotorrx7.com) old turbo setup. Sorry.

Wargasm

That setup on a 20B will be running short on breath by 5000 rpm if you ask me...

RX-Heven

iTrader: (1)

As does his dyno graph shows. It tops out early at about 650 rwhp. Aww shucks.

Turbo 3

iTrader: (3)

Wow... Wonder what my T-76 P-trim 1.32 will be like with a decent streetport... I thought I was going too big with that A/R so it wouldn't spool up until 4-4.5K...

Are you running the 9.0:1 comp rotors?

Will running S5 NA rotors make it spool up faster yet? I decided to upgrade to those as well while it was apart and the plan is to run 1 Bar of boost on pump gas with a little toluene to help offset the premix octane reduction.

RX-Heven

iTrader: (1)

Yes the na rotors will make it spool faster. I wish I had gone with those when I had mine built.

Pre-mix causes the octane rating decrease. Are you sure about this? Please explain.
Sounds like 'chatroom science' has been at play if you ask me.

Turbo 3

iTrader: (3)

I agree with you so I did some research on this because I didn't believe it either.

2 cycle oil; from what I've read about it in literature, makes the octane rating of gasoline go down by approximately 1-2 points when in a 100:1 ratio. Tolune, according to "Forced Induction Performance Tuning" by Alexander Graham Bell (page 185) has an octane of 106-108 and in a 20-30% mixture with gas, will give an approximate net octane rating of 98 when mixed with 92 octane.

I know I can't prove the 2-cycle oil theory at the moment but I've spoken to my engine builder/tuner about, read some books such as the above-mentioned, looked at manufacturers web sites and done more reading, etc, so I have to believe the 1-2 point reduction is accurate. I also know of one gentleman who always runs at least 30% tolune in his Cobra kit car with a 427 to reduce any pinging he gets under hard acceleration.

I'm always interested to learn more however so if you find something additional good or bad, be interesting to see what the thought is on the topic.

RX-Heven

iTrader: (1)

I wasn't questioning touline as I agree with you on that.

At our shop/school, we used to have Tim Wusz, the head of Union 76 racing department (also a chemical engineer) come and lecture twice a year to the students and I have also talked to him. This was one of the first tech questions I asked. He was sure it would have no affect on the rating one way or the other.
This does not mean it is so, but is the closest I have ever come to getting a definitive answer from a reputable source as I have also never seen anything worthwhile in print on the subject.

Also, my intuition tells me since it is mixed in such a small amount it would have little or no effect on the rating. Also consider that rotaries already inject oil (though not two stroke oil).

94RHDFD

iTrader: (3)

[QUOTE]Originally posted by Turbo 3
[B]Wow... Wonder what my T-76 P-trim 1.32 will be like with a decent streetport... I thought I was going too big with that A/R so it wouldn't spool up until 4-4.5K...

I'll let you know in few months that's the setup I have.

Turbo 3

iTrader: (3)

[QUOTE]Originally posted by 20B 3rd Gen
[B]Sweet I finally am supposed to have my rotor housings in from Mazdacomp late this week or early next week so after my ultra secret coating gets applied, she should be back together within 3-4 weeks tops... I can hardly contain myself

Be interesting to see after our motors are broke in what the dyno results will be. You would think they should be similar but the tuning will definitely be interesting since we are using different ecu's as well.