MaxSpeedingRods T70 Turbo For Dummies

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The Californian
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MaxSpeedingRods T70 Turbo For Dummies

Post by The Californian »

Here is the latest turbo that we are mesmerized by the low price.

https://www.maxpeedingrods.com/product/ ... arger.html

Noticed where it says 'oil cooled'.

Found Youtube where the guy had bought a 'T70' and it had provision for water cooling.

So.To be precise.This is what this company is selling as a 'T70'.

Found a post where they talked about how 'T70' is sort of an up in the air term.Will look for it again.Think it was on Driftworks.

Here is RX7 forum post with some info about it.

https://www.rx7club.com/single-turbo-rx ... od-617225/

Found the Driftworks one.

https://www.driftworks.com/forum/thread ... 70.127390/

Guy at the end seems to know his turbo sizes.
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Re: MaxSpeedingRods T70 Turbo For Dummies

Post by The Californian »

What will it do on our Corvair engine besides look too big for it?:)
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Re: MaxSpeedingRods T70 Turbo For Dummies

Post by Orr89rocz »

I suggest you stop looking at price and start looking at books like Turbocharging Performance Handbook by Hartman. Or even the classic Maximum Boost by Corky Bell.

Visit the Turbo b Garrett website for their tech pages turbo sizing 101, 102 and 103
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Re: MaxSpeedingRods T70 Turbo For Dummies

Post by englertracing »

Garrett even has an app called boost advisor.. tell it what your trying to do and it "matches" a turbo to your application
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Re: MaxSpeedingRods T70 Turbo For Dummies

Post by The Californian »

'stop looking at price'

Just irks us to pay $100 for the smallest Ebay turbo T3/T4 when for $40-60 more we can get a GT35 or GT45 or T70.

Something we can use later.'Grow into'.

Seems like it if it way too big it would be an 'intake accessory' and just interrupt the intake flow.

Did hear from Corvair expert and he said a T3/T4 would be 'laggy' on our little 145 cu in base motor.

Surprised me to hear even the hybrid with smaller turbine sounds like it is 'too much turbo'.

In the real world maybe we are stuck getting a T3/T4 to make meaningful measurements on the setup.

We'll get a big turbo someday!

Yes.We are studying all three editions of Hugh McInnes books.'71,'77 and '84.Making our head hurt!
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Re: MaxSpeedingRods T70 Turbo For Dummies

Post by af2 »

The Californian wrote: Thu Jul 30, 2020 6:55 pm 'stop looking at price'

Just irks us to pay $100 for the smallest Ebay turbo T3/T4 when for $40-60 more we can get a GT35 or GT45 or T70.

Something we can use later.'Grow into'.

Seems like it if it way too big it would be an 'intake accessory' and just interrupt the intake flow.

Did hear from Corvair expert and he said a T3/T4 would be 'laggy' on our little 145 cu in base motor.

Surprised me to hear even the hybrid with smaller turbine sounds like it is 'too much turbo'.

In the real world maybe we are stuck getting a T3/T4 to make meaningful measurements on the setup.

We'll get a big turbo someday!

Yes.We are studying all three editions of Hugh McInnes books.'71,'77 and '84.Making our head hurt!
Listen to the guys that ar making HP with the least expensive out there. Orr89 has been one you should pm
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Re: MaxSpeedingRods T70 Turbo For Dummies

Post by The Californian »

Okay.Guess we do seem obstinate and close minded.

Yes.We are hitching our wagons to the Hugh MacInnes books.

Yes.We do want to get a turbo and stick it on something now.The little Corvair engine.

Guess we are just on our own.So be it.
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Re: MaxSpeedingRods T70 Turbo For Dummies

Post by af2 »

The Californian wrote: Thu Jul 30, 2020 8:28 pm Okay.Guess we do seem obstinate and close minded.

Yes.We are hitching our wagons to the Hugh MacInnes books.

Yes.We do want to get a turbo and stick it on something now.The little Corvair engine.

Guess we are just on our own.So be it.
I do not understand at all what you are saying?

I simply said pm orr89. He has been messing with this since I have been here and knows his stuff when it comes to turbos. But all is good if you you want to keep on with the saying Dummies. That is not the reason we are on this sight.
Last edited by af2 on Thu Jul 30, 2020 8:50 pm, edited 1 time in total.
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Re: MaxSpeedingRods T70 Turbo For Dummies

Post by The Californian »

Well.

Seems like somebody is rolling up the welcome mat.

Okay.
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Re: MaxSpeedingRods T70 Turbo For Dummies

Post by af2 »

The Californian wrote: Thu Jul 30, 2020 8:49 pm Well.

Seems like somebody is rolling up the welcome mat.

Okay.
What?
Can I ask how old you are?
GURU is only a name.
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Re: MaxSpeedingRods T70 Turbo For Dummies

Post by The Californian »

I'm being polite and responding.

This has nothing to do with the topic.

That's enough.
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Re: MaxSpeedingRods T70 Turbo For Dummies

Post by The Californian »

Rereading 'Choosing a Turbo' chapter Hugh MacInnes 1977.

Little birdy tells us this.

Turbos do NOT follow RPM like Hillborn fuel injection and GMC blowers.

They MIGHT do nothing at lower RPM's and then:

The turbine 'fills up' with exhaust and starts moving faster with some oomph.

Then it is all done while engine keeps revving more.

We'll see how that turns out.
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Re: MaxSpeedingRods T70 Turbo For Dummies

Post by Orr89rocz »

Given your parameters of a stock natural aspiration corvair engine thats that small in cubic inch and only capable of making 80 hp in natural form, and only turning 5500-6500 rpm or so? If i recall right. Im suggesting you stay on the small side of things in order for it to spool at a reasonable rpm and still give plenty of hp increase. This is what you want to get your feet wet so to speak. Your engine doesnt have alot of energy to drive a turbine so its critical to size it correctly to get it to work right. Turbo lag is real, its actually boost threshold...a point in which there is enough turbine drive energy to reach shaft speed needed for the compressor to make positive pressure. If you only can rev to 6000 rpm you kinda want that boost threshold to come in abit over half that rpm to maybe 3/4 depending on your preferences in response time. Drag cars can get away with higher boost threshold, street fun cars and oem type turbo cars need much earlier activity

There are plenty of turbo 4-6 cyl cars of similar displacement out there, of various base hp levels. Following what they do will translate into a good working system on your engine. Thats why the sizes i mentioned in your other thread T25 and factory type td04 or k04 deals Could work well. Atleast a place to start. Bigger stuff wont spool well, will be closer to surge, Possibly overpowered, and overall a disappointment

The books and garretts articles will help size the compressor wheel optimal for your engine. Turbine will match based on the turbo manufacturers models. They usually are close in size
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Re: MaxSpeedingRods T70 Turbo For Dummies

Post by motormonkey »

Find turbo from a 3.8 buick. Draw thru and cheap. I gave one to somebody who's putting in on his corvair.
The best education and answers to all your questions will be from experience.
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Re: MaxSpeedingRods T70 Turbo For Dummies

Post by The Californian »

Thank you Motor Monkey

Good stuff! Word of mouth info.Our favorite!

'turbo from a 3.8 buick. Draw thru and cheap. I gave one to somebody who's putting in on his corvair'

Will pass that on immediately to a Corvair devotee.

'The best education and answers to all your questions will be from experience'

Learn by doing.Now we are 'researching' also.

Will make a post next with progress.
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