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Re: Honda B20 turbo in corvair

Posted: Wed Dec 24, 2014 12:31 pm
by MikeDTuning
i am current revising the throttle linkage yet again, (i think its my 30th try in this cars life) My current revision involves this part

http://www.jegs.com/i/JEGS+Performance+ ... 4/10002/-1" onclick="window.open(this.href);return false;

directly from the throttle pedal, to the throttle body. Morse cables are great, they are super low resistance, and eliminate many pieces of linkage. They can also be pushed, which is essential for making the stock pedal work

Re: Honda B20 turbo in corvair

Posted: Wed Dec 24, 2014 6:19 pm
by miniman82
Note: that tubular manifold will last you like 6 weeks before it cracks, suggest getting a quality cast one like this:

http://www.speedyracer.com/Honda-Civic- ... B18B18CB20" onclick="window.open(this.href);return false;


You'll save yourself in the long run, the tubular ones are only good for race cars. For daily use, the cast one shines.

Re: Honda B20 turbo in corvair

Posted: Thu Dec 25, 2014 7:49 am
by MikeDTuning
ive heard that before about the manifold, im still interested to give it a try. on other turbo cars i know a lot of the cause of cracked manifolds is exhaust weight vibrating up and down. of which this cars baby turbo, and 2 feet of exhaust piping is nowhere near as much as most hondas. Either way, we will see!!

Re: Honda B20 turbo in corvair

Posted: Thu Dec 25, 2014 9:53 am
by notched
Mike are you planning to take it to a drag strip once you get it sorted out? I am curious to see what it runs and how the trans holds up. What transaxle are you running? Gear ratio and anything done to strengthen it?

Re: Honda B20 turbo in corvair

Posted: Mon Dec 29, 2014 7:20 pm
by MikeDTuning
i am using a stock 66 corvair 4spd trans, realistically i am only planning on making 200-250whp, and 200ish wtq. This is not a stupid amount of power,, just double what the car had stock. I much more plan on autocrossing and driving it.

Also, Morse cables win. i got the throttle linkage made today, this is the best throttle feel this car has ever had. i highly recommend this as an upgrade to anybody in the corvair world

Re: Honda B20 turbo in corvair

Posted: Tue Dec 30, 2014 12:47 am
by bbodie52
:goodpost: Any chance of you posting some pictures, a list of materials and parts sources, and any guidelines or "lessons learned' as you went through the process of fabricating this linkage?

Re: Honda B20 turbo in corvair

Posted: Tue Dec 30, 2014 4:46 pm
by MikeDTuning
No problem! its really a pretty simple setup, which is why it works so well

To start, i should remind people that the engine side of my linkage will be entirely different than any stock motored corvair.

I will also remind people to check the cable length measurement. My throttlebody is located on the passengers side of the engine bay, facing towards the front of the car, because of this my throttle cable had to wrap around the engine bay, thus adding 4-5 feet in length. the part number of the cable i used is below. the jegs part number is 15714. it looks like the last 2 digits represent length (example, if you wanted a 9 foot cable, the part number would be 15709)

http://www.jegs.com/i/JEGS+Performance+ ... 4/10002/-1" onclick="window.open(this.href);return false;

The stock corvair pedal has 1.5-2 inchs of travel, to make sure you utilize the entire pedal its important confirm the throttle body/carb end requires the same 1.5-2 inchs of travel to rotate 90 degrees. Simple math then informs us that the lever length on the carb/throttle body should be between .955, and 1.27 inchs.

here is my throttle body side all bolted together

Image


this is the part i am sure more people will be interested in, the pedal end!

really its quite simple, i used stalk that can be purchased at any hardware store, home depot, or lowes. a 1/4 inch drill bit. a few self tapping screws, and a 6mm drill bit.

only 2 words of advice, the first of which is to support the cable as seen below, the rearward section keeps the cable from moving front-back, the forward section adds stability to keep the cable from bending to the side when being pushed.

second word of advice is make sure the the pedal is in good alignment with how the cable is being pushed. if its not, it will bind.

from here, its much simpler to just post a picture

Image

Image

Re: Honda B20 turbo in corvair

Posted: Fri Jan 16, 2015 1:16 pm
by MikeDTuning
im hoping somebody can help me out with a little bit of hard shifting diagnostics, i am suspecting shift alignment, Can anybody describe to me common symptoms of bad shift alignment?

Re: Honda B20 turbo in corvair

Posted: Sat Jan 17, 2015 7:36 am
by notched
When you say "hard shift", do you mean gear clash/grinding when shifting?
One of the common problems with poor bell alignment is difficultly getting into 4th gear. Did you dial indicate the bell housing opening to the flywheel/crank flange?

Re: Honda B20 turbo in corvair

Posted: Sun Jan 18, 2015 9:46 pm
by MikeDTuning
when moving all gear work fine, however when stopped i am having issues getting into any gears

Re: Honda B20 turbo in corvair

Posted: Mon Jan 19, 2015 7:06 am
by notched
Was this a problem before when it was Corvair powered. If not, check the free play adjustment as it sounds like your clutch is not fully disengaging.
Also check the clutch linkage for wear at the clevis pins and their respective holes at the z bar. These do wear and cause excessive slop that makes getting the free play adjustment difficult.
Too much free play will make it very difficult to disengage the clutch.

Re: Honda B20 turbo in corvair

Posted: Mon Jan 19, 2015 8:33 am
by MikeDTuning
the clutch is now fully hydraulic, so there is no more linkage. it using the honda OEM slave, and master, and seams to engage just fine

Re: Honda B20 turbo in corvair

Posted: Mon Jan 19, 2015 9:00 am
by notched
Did you drive this car with that trans prior to the swap?? If so, was it a problem before?

Re: Honda B20 turbo in corvair

Posted: Mon Jan 19, 2015 4:38 pm
by MikeDTuning
i did drive it on the old motor, and it was not an issue

I got it solved tonight, the issue was that the clutch fork was over-extending, a simple stopper behind the clutch fork has it shifting like a dream! This over extension was causing the clutch to not fully disengage. Notched was right!

As always
Thanks for all the help,

Re: Honda B20 turbo in corvair

Posted: Sat Jan 24, 2015 7:04 am
by MikeDTuning
the weather was a balmy 38 degrees in MA yesterday, so i took the car on its first longish drive (about 50 miles) i still have some software to dial in, but overall it will be a quick machine when its done! its amazing how much more responsive, and powerfull the little 4cyl is compared to the old Air cooler paperweight!

Also, the handling feels better, However i dont think this is due to any weight change, My primary complaint before was that the throttle linkage made it hard to control snap over-steer, Now this is a thing of the past!

on the topic of weight, some numbers i googled was that a stock vair 110 motor, with manual trans bell housing flywheel, and starter weighs 312lbs the honda b20 in similar trim is said to weigh 318lbs. (wet) i know there is more parts i added, like a radiator, hoses, and turbo. but i also subtracted a heavy cast iron exhaust manifold. from the honda motor, And at time of install i replaced a lot of heavy throttle, and clutch linkage parts with much lighter, and better working assemblies

realistically i doubt there is more than 40lbs total weight difference between the two setups. its possible the COG raised a little, but i doubt it is anything noticeable

Running errans in it

Image

Re: Honda B20 turbo in corvair

Posted: Sat Jan 24, 2015 9:49 am
by Allan Lacki
I'm impressed! I notice that the front end of the car hasn't been cut open for a radiator. Where did you mount it?