Honda-SOHC

SOHC.co.uk Forums => CB750 => Topic started by: Voxonda on October 24, 2007, 11:48:15 AM

Title: Turbo power
Post by: Voxonda on October 24, 2007, 11:48:15 AM: According to SteveD I should open a new topic about my latest "brainwave", turbocharging one of my CB750 or in this case CB850.
My 'second' bike, the situp and beg one, will be treated with a Garrett T2 fed by a Mikuni HRS 42 carb. Installation of the Turbo and other parts, like exhaust, oil feed and return will be done by myself. So that will be a challenge, since I know very little about Turbocharging. One thing I do know, that it is a effective way of filling the engine.
Will keep you posted.

Cheers, Rob
Title: Re: Turbo power
Post by: peewee on October 24, 2007, 10:28:00 PM: Hi Rob,
I think the turbocharger is likely to fill your engine full of valves and pieces of moltern pistons,
I'm no turbo expert but i think the compression needs to be lowered and a 'safe' rev limit set to avoid turning your Honda engine into a minature Blast furnace.Good luck with your venture and let us know how you get on
Cheers
Peewee
Title: Re: Turbo power
Post by: Voxonda on October 24, 2007, 10:52:45 PM: Hey peewee,

You've just shown me the down side of it all!! The cr will be lowered, but that depence a lot of how much 'boost' you're using. But it should/will be lowered to keep 'detonation' away. In the Garrett there's a boost-valve that opens if the boost is higher then preset. But I will be starting on the safe side to keep the engine in one piece.

Cheers, Rob
Title: Re: Turbo power
Post by: Voxonda on October 28, 2007, 03:39:37 PM: In order keep the CR somewhere around 8.5 :1, I will be using the conrods of our sister, the DOHC750. These are approx. 1.5 m/m shorter, big- and small-end are the same size. Bolts are a bid stronger and the rods themselves look a bit beefier. I think that is a more advanced solution then placing a spacer beneath the barrel.
Still waiting for the Mikuni and the Turbo to arrive. Then the real work can begin.

Cheers, Rob
Title: Re: Turbo power
Post by: dave400 on October 29, 2007, 07:09:22 PM: Rob, sounds like you have a bit of reading and a lot of work ahead, :o good luck with your new venture
Title: Re: Turbo power
Post by: Voxonda on October 29, 2007, 07:59:41 PM: Quote from: biffta on October 29, 2007, 07:09:22 PM
Rob, sounds like you have a bit of reading and a lot of work ahead, :o good luck with your new venture
Title: Re: Turbo power
Post by: Voxonda on October 29, 2007, 09:46:24 PM: This is the Mikuni:
(http://i238.photobucket.com/albums/ff74/voxonda/02ef_1.jpg)
Title: Re: Turbo power
Post by: Voxonda on October 29, 2007, 09:47:15 PM: The HD studs:
(http://i238.photobucket.com/albums/ff74/voxonda/a10_lg.jpg)
Title: Re: Turbo power
Post by: Voxonda on October 29, 2007, 09:48:10 PM: Of course, the Garrett T2:
(http://i238.photobucket.com/albums/ff74/voxonda/4591_1.jpg)
Title: Re: Turbo power
Post by: Voxonda on October 29, 2007, 09:49:14 PM: The oil return:
(http://i238.photobucket.com/albums/ff74/voxonda/Afb271.jpg)
Title: Re: Turbo power
Post by: Voxonda on October 29, 2007, 09:50:20 PM: And the difference in conrods:
(http://i238.photobucket.com/albums/ff74/voxonda/Conrod_750SOHC_750DOHC_1.jpg)

Cheers, Rob
Title: Re: Turbo power
Post by: peewee on October 30, 2007, 11:49:46 AM: Hi rob sorry to take the mickey as you seem to know quite a lot about turbocharging theres an interesting site that i found at max-boost.co.uk
it goes into fueling lubrication etc
cheers and good luck
peter.
Title: Re: Turbo power
Post by: Voxonda on October 30, 2007, 09:49:42 PM: Quote from: peewee on October 30, 2007, 11:49:46 AM
Hi rob sorry to take the mickey as you seem to know quite a lot about turbocharging theres an interesting site that i found at max-boost.co.uk
it goes into fueling lubrication etc
cheers and good luck
peter.

Hey Peter, thanks for that interesting site. All I really know about turbo's is from books and stuff, not from own experience yet. But after reading quite a bit about it, it's not really all that high tech. What I think is important, is what do you want to achieve? Just plain power, or a rideable bike for street use. I want a bit more power, more torgue and a bike that lasts. You can easily overdo things, with a lot of damage as a result.
Cheers, Rob
Title: Re: Turbo power
Post by: SteveD CB500K0 on October 31, 2007, 07:53:58 AM: Do you read what was written in the 70's when people turbo'd Z1s. Even Kawi made the Z1R Turbo.

Keep the waste gate setting low and watch out for the killer turbo-lag!
Title: Re: Turbo power
Post by: Voxonda on October 31, 2007, 08:15:52 AM: Quote from: SteveD CB500F on October 31, 2007, 07:53:58 AM
Do you read what was written in the 70's when people turbo'd Z1s. Even Kawi made the Z1R Turbo.

Keep the waste gate setting low and watch out for the killer turbo-lag!

Hey steve, I know them stories! Wanted to own one myself back then, but couldn't get hold of one, back then, so ended up with a normally aspirated one.
I'll keep your advise in mind, I don't want to hurt myself!!!

Cheers, Rob
Title: Re: Turbo power
Post by: peewee on November 01, 2007, 11:24:38 AM: Hi Rob
I have noticed that your mikuni carb is a high performance carb for a Hardly ableto so i can estimate in top gear with full boost on the turbo you should hit at least 55mph
Peter
Title: Re: Turbo power
Post by: Voxonda on November 01, 2007, 06:34:29 PM: Quote from: peewee on November 01, 2007, 11:24:38 AM
Hi Rob
I have noticed that your mikuni carb is a high performance carb for a Hardly ableto so i can estimate in top gear with full boost on the turbo you should hit at least 55mph
Peter

Sh........t I hoped to reach 65mph!!!!!!!!!!!! ::) ::) ::)
Today I got my carb from the States. At least it looks impressive.

Cheers, Rob
Title: Re: Turbo power
Post by: Voxonda on November 01, 2007, 09:44:48 PM: Harley power!!!
(http://i238.photobucket.com/albums/ff74/voxonda/Afb275.jpg)

Sorry, Hartly any power!
Title: Re: Turbo power
Post by: Voxonda on November 27, 2007, 08:48:28 PM: Work in progress.(http://i238.photobucket.com/albums/ff74/voxonda/Afb287.jpg)
Title: Re: Turbo power
Post by: Voxonda on November 27, 2007, 08:51:29 PM: Though with a 'fake' engine.
(http://i238.photobucket.com/albums/ff74/voxonda/Afb286.jpg)

Sorry for the poor quality of the pic's.
Title: Re: Turbo power
Post by: Voxonda on December 11, 2007, 09:04:49 PM: At last, the Garrett T2 is in, let's position him:
(http://i238.photobucket.com/albums/ff74/voxonda/Afb291.jpg)
Title: Re: Turbo power
Post by: Voxonda on December 17, 2007, 03:55:04 PM: And put the Mikuni on:
(http://i238.photobucket.com/albums/ff74/voxonda/Afb294.jpg)
Title: Re: Turbo power
Post by: dave400 on December 17, 2007, 08:43:04 PM: That carb looks bigger than my 400 engine! ;)

Dave
Title: Re: Turbo power
Post by: Voxonda on December 18, 2007, 08:07:26 AM: Quote from: biffta on December 17, 2007, 08:43:04 PM
That carb looks bigger than my 400 engine! ;)

Dave

Hi, Dave

Only reason to put a K&N filter on is to prevent the carb from sucking my knee in!

Cheers, Rob
Title: Re: Turbo power
Post by: Voxonda on December 19, 2007, 08:18:27 AM: This is how far the 'project' is right now.
(http://i238.photobucket.com/albums/ff74/voxonda/Afb297.jpg)
What do you think?

Like to take this opportunity to wish you all the best for 2008 and a merry Christmas!!

Cheers, Rob
Title: Re: Turbo power
Post by: dave400 on December 19, 2007, 06:02:07 PM: I love that carb! 8)

Merry Christmas Rob

Dave
Title: Re: Turbo power
Post by: pae on December 20, 2007, 05:34:20 PM: Wow, it's looking good. Really enjoying this and looking forward to seeing more. Happy Christmas!

regards, Phil
Title: Re: Turbo power
Post by: peewee on January 02, 2008, 10:42:08 PM: Happy new year Rob and to all listening
your project seems to be flying along I wish i could work at your pace.
P.S. are they TZ G spec Rotors/discs you have on the front ? I only have one on my TZ350 with a lockheed caliper and that is plenty good enough , my friend raced a tz750 in the 80's with the same discs and lockheed calipers he never complained about stopping.
Cheers
Pete.
Title: Re: Turbo power
Post by: Voxonda on January 03, 2008, 08:36:04 AM: Hey Pete,
I only hope my project will be 'flying' once they are ready! ;) ;)
The disks are a bit of a mystery, seems that Yamaha never produced TZ-disks bigger then
Title: Re: Turbo power
Post by: Voxonda on October 04, 2008, 05:06:57 PM: Hey there,

It has been awaile but still busy with my pressured baby. Here with, some, of her new clothes on.
(http://i238.photobucket.com/albums/ff74/voxonda/tankseat001.jpg)
(http://i238.photobucket.com/albums/ff74/voxonda/tankseat002.jpg)
(http://i238.photobucket.com/albums/ff74/voxonda/tankseat006.jpg)
(http://i238.photobucket.com/albums/ff74/voxonda/tankseat007.jpg)

Cheers, Rob
Title: Re: Turbo power
Post by: pae on October 04, 2008, 10:28:57 PM: Looking good, got any pictures of the inlet manifold?

regards, Phil
Title: Re: Turbo power
Post by: Voxonda on October 04, 2008, 10:36:53 PM: Quote from: pae on October 04, 2008, 10:28:57 PM
Looking good, got any pictures of the inlet manifold?

regards, Phil

Hey Phil,

(http://i238.photobucket.com/albums/ff74/voxonda/Newprojekt003-1.jpg)
(http://i238.photobucket.com/albums/ff74/voxonda/Plenummontage001.jpg)

Cheers, Rob