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confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: American Mel ()
Date: November 22, 2022 10:36PM

In order to avoid hijacking Phil's turbo thread, or Nic's Crown exhaust housing thread, I will post my question as a separate thread.

Can anyone tell me what differences one would expect between, . . . . .

A. - A totally stock 180 turbo
and
B. - A Hybrid, (stock 180 compressor mated to a stock 150 Exhaust)
and
C. - A stock 180 compressor with a Crown Exhaust Housing

I guess what I am trying to figure out, is what advantage is there to using a Crown Exhaust Scroll over just assembling a 180/150 Hybrid turbo???
and
Just HOW BIG an advantage is option B or C over just staying stock?
While spooling faster, won't you lose some Top-End with the Smaller/Tighter Scroll?

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WA. state, 1 mile south of the Canadian border, I am not at the end of the world, but you can see it from here.

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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: v8vair ()
Date: November 23, 2022 05:06AM

Mines a 180 cold side including carb and 150 exhaust, makes boost in all the gears, pulls hard 2nd 3rd and high gear. Will peg the boost gauge in 3rd and 4th on the highway.Big Fun
The stock 150 made boost in 3rd and 4th , felt good but nothing in 1st, a little in 2nd, on the highway was when it pulled well

1964 Bill Thomas Monza Replica Racer
1964 Spyder Street Car
1998 Honda Prelude Dirt track car
1967 Crown V8 under construction
Mike Levine
Cumming Georgia
North of Atlanta

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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: kmart356 ()
Date: November 23, 2022 06:53AM

What @v8vair said!

My 2cents. The B-exhaust side helps with quicker spooling and I will add that it is really about air flow plus efficiency.
When i was reconfiguring my Spyder turbo a wise man gave me the following guidance (cannot remember who but it was a member here sad smiley ).
The question i had asked was relative to F-flow vs E-flow intake side since I already had a modified turbo.

>>> The F flow is efficient at lower boost levels and the efficiency drops as boost is increased past 12-13 psi.

>>> The E Flow is most efficient at levels above 12-13 psi. Think 18-30 psi to get the most efficiency out of it.

>>> Putting a YH in front of it is like putting your hand over your mouth and breathing through your fingers.

>>> I would only do the E flow IF you plan on pushing more than 12-13 psi, have a larger carburetor AND you have a wastegate.

Based on that advice, I went with a F intake/B exhaust and eventually upgraded from Stromberg WW to the Mikuni HSR45. Currently getting 17-18psi and making the wastegate work.

The chart shows cfm flow for the B-flow/F-flow/E-flow intakes (dashed lines) along with Carter YH/Stromberg WW/Mikuni HSR45/Weber DCOE/Q-jet carbs (solid lines).

The Stromberg WW was a success as it increased flow over the Carter YH. Plenty of turbo guys upgraded to the Weber DCOE with the late model turbo (F-flow) which matched up nicely and finally those guys that want mucho boost and high end power choose the E-flow and bolt on the Q-jet both high cfm rates.
The Mikuni HSR45 slots in nicely above the Stromberg and has been a great performer with the F/B turbo.



Ken
'62 Spyder
Florida


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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: jazzworkerbee ()
Date: November 23, 2022 10:47AM

I have a 64 hot side with a 65 cold side (rebuilt by Ray Sedman) that draws through a progressive Weber 40 DCOE. I also have a wastegate with a 10 psi spring. It came with a 14, but I'll wait until I have water injection and build an engine with forged pistons to try for bigger boost.

When I first got the car, my turbo was a stock 180 and a super restrictive Weber downdraft.It only got boost at the top of 3rd and 4th and was really sluggish on the bottom end. Now its super responsive and I get boost in 1st and 2nd. Seems to have a more torque too. Granted, I haven't driven it very far yet, and I haven't built enough boost to hear the waste gate, but it is far and away better than it was originally. I still have a ways to go, but I think I'm going in the right direction for sure!

Daniel Atkinson
Tacoma, WA
65 Turbocharged Corsa

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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: American Mel ()
Date: November 23, 2022 01:56PM

Great info.
Seems to back up what I have always heard.
NOW, does anyone have experience with the Crown Housing?
How does it compare to Stock?
And how does it compare to an F/B Hybrid?
Is it better than the Hybrid, or essentially just the same effect, but from an Aftermarket, rather than using stock parts?

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WA. state, 1 mile south of the Canadian border, I am not at the end of the world, but you can see it from here.

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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: 110PG ()
Date: November 23, 2022 02:38PM

I'm paying attention here. I have a Crown housing that I may or may not keep depending on the answers here.

Joe Nelson
Western WI

66 Corsa Turbo CPE
84 380SL
69 Monza CPE (sons car)

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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: American Mel ()
Date: November 23, 2022 04:57PM

110PG Wrote:
-------------------------------------------------------
> I'm paying attention here. I have a Crown housing that I may or may not keep depending on the answers here.


Yes, I have some decisions to make, since I have a small pile of Turbo parts I have acquired in small stashes I bought over the last couple years.

A couple Stock turbos
An F/B turbo
A Crown Exhaust Scroll
And the Bill Devin turbo engine, with Michael LeVeque progressive Weber mounted on a Turbonectics turbo with wastegate.

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WA. state, 1 mile south of the Canadian border, I am not at the end of the world, but you can see it from here.

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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: 63turbo ()
Date: November 23, 2022 05:12PM

American Mel Wrote:
-------------------------------------------------------
> In order to avoid hijacking Phil's turbo thread, or Nic's Crown exhaust housing thread, I will post my question as a separate thread.
>
> Can anyone tell me what differences one would expect between, . . . . .
>
> A. - A totally stock 180 turbo
> and
> B. - A Hybrid, (stock 180 compressor mated to a stock 150 Exhaust)
> and
> C. - A stock 180 compressor with a Crown Exhaust Housing
>
> I guess what I am trying to figure out, is what advantage is there to using a Crown Exhaust Scroll over just assembling a 180/150 Hybrid turbo???
> and
> Just HOW BIG an advantage is option B or C over just staying stock?
> While spooling faster, won't you lose some Top-End with the Smaller/Tighter Scroll?


A: The totally stock 180 Turbo has a A/R on the exhaust housing of .72 and that is a freaking huge housing for a street car... even nowdays, for street use , .63 is a lot more like it and .55 is very common. At .72, it is almost perfect for drag racing, because you're supposed to be hitting your peak boost in 3rd. The inlet compressor for the stock F is a dead ringer size wise to a gt-25, and those are capable of flowing enough air for 350hp. The issue with doing this with an F is that huge exhaust housing wont allow the turbo to spin fast unless it is really loaded hard and has enough intake area, which isnt going to happen without a really big carburetor or throttle body or deleted entirely like for a blow through set-up. And the design of the compressor wheel isnt very efficient at the boost levels that will flow 450 cfm which is where that compressor is maxed out.
B: When the smaller B exhaust turbine and housing is put on the F compressor, even though the B exhaust housing has an A/R of .72, it speeds up the compressor wheel so much that it is functionally identical to putting a .55 A/R exhaust housing on the stock F turbo. This combo is WAY more snappy than the stock F and allows the compressor to spin high enough so as to flow what that compressor is really capable of. The only downside to this approach is basically the same as putting a .55 A/R exhaust housing on the stock F, is that it limits the exhaust flow enough that your peak power and rpm will end up being limited from exhaust back pressure. Not a big deal unless you are spending a lot of time at 20+ psi!
C: That question depends on which Crown housing you got. A .55 would be the same as an F/B combo, a .63 would still boost quicker than stock but less exhaust restricted, and the .8, which is probably the biggest one they did, will take more engine rpm and load to hit the same boost, but will move the exhaust limiting rpms much higher... something like 7000 rpm.

------------------------------------

Kevin Nash
Friday Harbor Washington
63 Spyder, Daily driver, EFI read about my project here: [corvaircenter.com]
first test start on EFI here:[www.youtube.com]
first official EFI boost test here:[www.youtube.com]
My new fan! [corvaircenter.com]
engine less 62 Spyder
Canadian 64 Monza Parts car
Test Start#2 [www.youtube.com]



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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: zarfnober ()
Date: November 23, 2022 06:04PM

Whatever ex hsg you choose, don’t forget that another limiting factor is the stock turbo exhaust system, that crossover pipe flows about as well as a constipated cheese eater, and the stock ex manifolds don’t help either. When I first assembled my 3.1 140/big tube headed turbo motor, I used the stock carb/late turbo using a Crown ex hsg, anything over 2500 rpm produced instant 10 psi boost in any gear. I was using a custom free flowing exhaust system. After getting some miles on it, I hooked up the sdsefi ecu, 2-1/2” throttle body going into an E-flow compressor and stock early ex housing, and driving around just trying to get a basic tune, it was making boost just giving it a little gas. A hard to find vacuum leak kept a proper tune being achieved, but that's another story.

The otherwise stock current engine has an F/Crown turbo and a Blackhawk EFI throttle body, crossover and manifolds have always been wrapped, and with the throttle body being the same diameter as the turbo inlet, throttle response is superior to the carb, and the boost comes on much quicker than the carb. Wastegate is currently set at 3psi for tuning. Now that I have the tach working again, the ecu needed some diodes in the tach wire to send a proper signal to the tach, I’ll provide a more accurate boost/rpm starting point.

I plan on upgrading to 140 ex manifolds and a properly sized crossover and inlet over winter using mandrel bent pipes, I’ll probably increase the downpipe while I’m at it. I’m somewhat surprised no one ever offered an aftermarket turbo exhaust.

Lee Joseph/GN Vair built a real nice stainless exhaust for his car, and he’s run 15’s in the 1/4 with an otherwise stock 180. And Kevin Nash probably has the most EFI turbo Corvair miles out there, he’s working on a larger intake crossover to make more power with less boost. It’s all about flow, even when it’s forced.

YMMV

Rocco

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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: jjohnsonjo ()
Date: November 23, 2022 06:35PM

I have been at this a long time, for many years all anyone would talk about was how much throttle response was lost if you opened up either intake or exhaust. This is all refreshing info to me as I always thought the amount of flow could easily be increased without significant losses.

J.O.

65 Corsa Turbo Vert
79 Honda XL 500S
69 Honda CL 160 D
2010 BMW F 650 GS
2003 Bounder 36D
2013 KIA Optima SX turbo-AKA ZIPPY (wife,s car)
69 Newport Holiday Sailboat
Baja 150 dune buggy cart
Coleman HS 500 UTV
2016 KIA Sorento SXL Turbo

Bethlehem,Pa


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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: 63turbo ()
Date: November 23, 2022 09:07PM

zarfnober Wrote:
It’s all about flow, even when it’s forced.
>
> YMMV
>
> Rocco


smileys with beersmileys with beersmileys with beer

THIS!!!!

------------------------------------

Kevin Nash
Friday Harbor Washington
63 Spyder, Daily driver, EFI read about my project here: [corvaircenter.com]
first test start on EFI here:[www.youtube.com]
first official EFI boost test here:[www.youtube.com]
My new fan! [corvaircenter.com]
engine less 62 Spyder
Canadian 64 Monza Parts car
Test Start#2 [www.youtube.com]



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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: playerpage ()
Date: November 23, 2022 09:07PM

Isn't a Mikuni HSR45 a motorcycle carb? How much modification does THAT take?

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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: American Mel ()
Date: November 23, 2022 10:19PM

playerpage Wrote:
-------------------------------------------------------
> Isn't a Mikuni HSR45 a motorcycle carb? How much modification does THAT take?


He did an entire thread on it.
Do a search for, . . . . . New Turbo Carb - Mikuni HSR45 smoothbore carburetor

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WA. state, 1 mile south of the Canadian border, I am not at the end of the world, but you can see it from here.

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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: zarfnober ()
Date: November 24, 2022 04:15AM

One more thing when it comes to our quest for more boost, get a wastegate. It’s not there to simply control boost pressure, it gets rid of, you guessed it, waste. At 15 psi, you’ve basically turned your 164” motor into a small block Chevy, it’s gotta go somewhere. Say it’s set at 10 psi and your foot is in it, that waste gate dumps excess exhaust gases, a great thing with our cooling compromised air cooled Vairs, easier on head temps and detonation prevention. JMO

Rocco

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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: Chet Jr ()
Date: November 26, 2022 07:12PM

I have very fond memories of my HI boost Corvair back in the day.

It was a very fast car but never seemed to be able to pass a gas station.

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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: 110PG ()
Date: November 27, 2022 07:02AM

So after reading the responses, Kevin had a pretty specific response to the main question. How can you identify which late crown housing you have and is a waste gate necessary with this housing when everything else is stock? I'm not on a quest for more boost but I have on hand parts I could use and want everything to appear stock.I didn't realize Crown made 3 different housings for the 180. Thanks

Joe Nelson
Western WI

66 Corsa Turbo CPE
84 380SL
69 Monza CPE (sons car)

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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: 63turbo ()
Date: November 27, 2022 08:39AM

I know someone that has every single crown exhaust housing there was and will attempt to get ahold of him. At least "some" of those housings do have the A/R number on them somewhere. I dont know if it necessarily means something if that number isnt on it.

------------------------------------

Kevin Nash
Friday Harbor Washington
63 Spyder, Daily driver, EFI read about my project here: [corvaircenter.com]
first test start on EFI here:[www.youtube.com]
first official EFI boost test here:[www.youtube.com]
My new fan! [corvaircenter.com]
engine less 62 Spyder
Canadian 64 Monza Parts car
Test Start#2 [www.youtube.com]



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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: 63turbo ()
Date: November 27, 2022 09:13AM

So much for relying on memory!! ouch! I went and found the posts on fastvair about the exhaust housings, and it appears that Crown offered only one housing, and it was a .55 A/R. There were 2 kinds of those, one had a bolt adjuster thing
to further tighten the scroll and the other did not. The other housing options were done by Rayjay, although there "might" be others that can work if it has a T4 flange, as this is what our stock housings use to bolt to the inlet pipe.

------------------------------------

Kevin Nash
Friday Harbor Washington
63 Spyder, Daily driver, EFI read about my project here: [corvaircenter.com]
first test start on EFI here:[www.youtube.com]
first official EFI boost test here:[www.youtube.com]
My new fan! [corvaircenter.com]
engine less 62 Spyder
Canadian 64 Monza Parts car
Test Start#2 [www.youtube.com]



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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: zarfnober ()
Date: November 27, 2022 09:51AM

110PG Wrote:
-------------------------------------------------------
How can you identify which late crown housing you have and is a waste gate necessary with this housing when everything else is stock?

IMO, yes on the waste gate. Let’s say you wrap your exhaust manifolds and crossover, and get the Crown hsg, you’re gonna make boost quicker AND more of it, you can see it go as high as 15-17psi at crossover/carb pad on the head, for a few reasons, but let’s keep it simple. After you have it tuned and that boost really creeps up high, pay attention to how it feels power wise compared to what it did prior to the Crown hsg. Get an adjustable wastegate and set it at 10 psi, run it hard and tell me if it doesn’t feel like it’s running better, and far less likely to ping. This is where flow is so important on our turbos, Chevy was keeping it simple for warranty’s.

I’d also get a wide band 02 sensor for tuning, at high boost you’ll see that A/F get way richer than you really want, and getting the assortment of jets and metering rods will make tuning with that meter easy. And that CB Performance Black Box ignition is a wise choice too. And water/meth injection, see how quickly the fun and money level increases with boost?????

Have fun!

Rocco

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Re: confused smiley Turbo Differences - Stock 180, 180/150 hybrid, and 180/Crown ? ? ? confused smiley
Posted by: The Stig ()
Date: November 28, 2022 05:30PM

Since the subject has moved to it - I am interested in pictures / placement of a wastegate. I have one to install on my turbo that I am currently building. Concerned about placement and the actual exhaust from it.

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