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Topic Review (Newest First)
07-01-2013 01:26 PM
AutoGear Hell Rick Dobbertin's J2000 was done in what 1985? Twin Magnusson SC/Twin Roto-Master turbos/20 port nitrous injection on an all aluminum SBC. Overkill? Sure! Impractical? Absolutely! But the beauty of the fabrication and the ability to see it through is astounding. And I distinctly remember that car driving past my house when I was a kid (before it was in paint)
06-30-2013 10:43 AM
Augusto
Quote:
Originally Posted by vinniekq2 View Post
totally unpractical, but who cares, it's beautiful, awsome work.
06-30-2013 10:35 AM
Augusto
Quote:
Originally Posted by techinspector1 View Post
Yeah, well if 8 turbos are so freakin' cool, where are the dyno figures??????????

As far as getting fuel into the bike carbs, I conceived the fix for that several decades ago. You need a fuel reservoir that sits higher than the carbs so fuel can flow by gravity into the carbs, just like the stock tank arrangement. Inside the reservoir is a float that rises and falls to switch on and off a small electric pump which re-feeds the reservoir from a main fuel tank. Think of this reservoir as about the size of a kitchen toaster. As long as the bottom of it is higher than the carb inlet, it will work. You could have this reservoir in plain sight or you could hide it behind some sheet metal work.
in shifter kart racing we use motorcycle engines and feed the carb with a pump, but we use a Tee close to the carb to return most of the fuel back to the tank so very little pressure reaches the carb, anything over 1 psi will force open the needle in a bike's carb, I have also used the reservoir but returning the excess fuel works just fine and is simpler.

a turbocharger will not work with motorcycle carbs, the pressure will keep the vaccum piston closed all the time and the engine will not accelerate under boost.
06-29-2013 10:43 PM
vinniekq2 Tech,hows this for a confused engine?
06-29-2013 05:22 PM
techinspector1
Quote:
Originally Posted by nine4gmc View Post
was it this engine with eight turbos? this cat built a killer looking setup for sure, but its not motorcycle carbs on a Pontiac 6...

Hot Rods and Cool Stuff <--- Eight Turbos
Yeah, well if 8 turbos are so freakin' cool, where are the dyno figures??????????

As far as getting fuel into the bike carbs, I conceived the fix for that several decades ago. You need a fuel reservoir that sits higher than the carbs so fuel can flow by gravity into the carbs, just like the stock tank arrangement. Inside the reservoir is a float that rises and falls to switch on and off a small electric pump which re-feeds the reservoir from a main fuel tank. Think of this reservoir as about the size of a kitchen toaster. As long as the bottom of it is higher than the carb inlet, it will work. You could have this reservoir in plain sight or you could hide it behind some sheet metal work.
06-29-2013 01:50 PM
2x4 Barrels
best girlfriend ever

Hi vinniekq2

It was a gift from my girl friend in 1999.I did not ask her but I kissed her till my face was ready to fall off.She had to move because of her job and have not heard from her since 2001.Use a driffernt thread.I read it only to laugh my nut`s and bolt`s off.


2x4`s
06-29-2013 11:29 AM
vinniekq2 2x4 where did you get that spoiler?
03-19-2012 10:15 AM
Augusto
Quote:
Originally Posted by RetiredHotRodder
Thanks for the info and the link Augusto.

You had mentioned:

>not to question your project, but why doing all that machine work for only 200 cubes? I would use a 300 cid (also known as the 4.9) inline six ford that has external intake and exhaust manifolds? plus the 100 extra inches will give you a much rewarding engine, and with the six carbs it would just look awsome.
I'm already installing an I6 300 in my son's granada, look at my pictures, or the thread I started for it :

http://www.hotrodders.com/forum/for...ada-205602.html


I'm sort of in a similar situation as you are as far as why I'm using a 200 and doing all that machine work on a 200.
This is also a fun project I'm teaching my grandson some skills as we go along, like sheet metal work, welding, torches, proper use of power tools, the lathes, mill, drill press, etc. I just hadn't mentioned it before due to my post already becoming rather lengthy.

Why a 200? I have 3 of them in my garage coupled to standard transmissions. I'll be showing my grandson how to rebuild a simple standard transmission as well as the engine work and upgrades for both strength and performance.
All the machine work in my case is basically free since I have the equipment in my garage and am a retired machinist and welder.

I can buy sheets of aluminum at cost to make the T style body from and have the sheet metal equipment in my garage also so that will keep costs way down.

I also have several motorcycle engines on my garage shelves with some decent Mikuni carbs on them. I can show my grandson how to rebuild the first one, then let him take it from there with the following other 5 carbs. These are all some of the things I've just got great deals on over the years and could not part with them.

I had a Yamaha Maxim 750 before I retired. I put a Kerker 4 into 1 muffler on. The sound of that Kerker was so great I nearly had a mental orgasm the first time I fired it up. So I'm giving some thought to using 2 Kirkers on this 200 inline with 3 into 1 (2 times), by running the exhaust tubes individually as long as possible down the side of the hot rod for more torque, then couple 3 exhaust tubes into 1 collector to attach the Kirkers to near the end with 2 kickout exhaust tubes on the end of the Kerkers. Before I actually use two Kerkers I'll do my homework to make sure the flow & cfm is good for this set-up.

In this case, I have nearly everything I need for this project that will help keep costs down.

I'm estimating our little hot rod project shouldn't weight over 1,000 pounds, so the power to weight ratio should be satisfactory and a fun little hot rod to play around with.

Your son's and your 300 inline project sounds great. As sixes go, I've always liked the Ford 300. If I had some 300's as readily available as the three 200's I already have, I'd be using the 300. It's a great choice.

Best wishes.
sounds like a real fun project, and doing it with your grandson is enough reason to start it.

Please post a pic of the head once it's milled down the manifolds, I wonder if there's enough meat inside to machine a flat surface for the manifolds, you might have to weld up a lot, probably some water jackets will show up, I'm really courious to see how it's inside.

No problem about the mc carb's lack of accelerator pumps, they don't need one, the vaccum slide takes care of it, you already know bikes and how they work just fine with them mikunis.

About the Kerker, yes I know the sweet sound they make, orgasmics to say the least, but I'm sure thet's not possible with a car engine, I have tried for years with 4 cylinders but no luck, some come close but not, I'm sure is a combination of cam timing, ligth weight cranks, high revs, short runners, etc which combine for that incredible sound, but I'm sure your six will sound good, I will not use a header, just a free flowing 2.5" pipe with 2 glaspacks, I might build a 3Y header later.

keep us posted and don't forget the pics, good luck amigo.
03-18-2012 07:39 PM
nine4gmc was it this engine with eight turbos? this cat built a killer looking setup for sure, but its not motorcycle carbs on a Pontiac 6...

http://www.hotrodsandcoolstuff.com/enginebuild.html <--- Eight Turbos
03-18-2012 06:42 PM
RetiredHotRodder Thanks for the info and the link Augusto.

You had mentioned:

>not to question your project, but why doing all that machine work for only 200 cubes? I would use a 300 cid (also known as the 4.9) inline six ford that has external intake and exhaust manifolds? plus the 100 extra inches will give you a much rewarding engine, and with the six carbs it would just look awsome.
I'm already installing an I6 300 in my son's granada, look at my pictures, or the thread I started for it :

http://www.hotrodders.com/forum/for...ada-205602.html


I'm sort of in a similar situation as you are as far as why I'm using a 200 and doing all that machine work on a 200.
This is also a fun project I'm teaching my grandson some skills as we go along, like sheet metal work, welding, torches, proper use of power tools, the lathes, mill, drill press, etc. I just hadn't mentioned it before due to my post already becoming rather lengthy.

Why a 200? I have 3 of them in my garage coupled to standard transmissions. I'll be showing my grandson how to rebuild a simple standard transmission as well as the engine work and upgrades for both strength and performance.
All the machine work in my case is basically free since I have the equipment in my garage and am a retired machinist and welder.

I can buy sheets of aluminum at cost to make the T style body from and have the sheet metal equipment in my garage also so that will keep costs way down.

I also have several motorcycle engines on my garage shelves with some decent Mikuni carbs on them. I can show my grandson how to rebuild the first one, then let him take it from there with the following other 5 carbs. These are all some of the things I've just got great deals on over the years and could not part with them.

I had a Yamaha Maxim 750 before I retired. I put a Kerker 4 into 1 muffler on. The sound of that Kerker was so great I nearly had a mental orgasm the first time I fired it up. So I'm giving some thought to using 2 Kirkers on this 200 inline with 3 into 1 (2 times), by running the exhaust tubes individually as long as possible down the side of the hot rod for more torque, then couple 3 exhaust tubes into 1 collector to attach the Kirkers to near the end with 2 kickout exhaust tubes on the end of the Kerkers. Before I actually use two Kerkers I'll do my homework to make sure the flow & cfm is good for this set-up.

In this case, I have nearly everything I need for this project that will help keep costs down.

I'm estimating our little hot rod project shouldn't weight over 1,000 pounds, so the power to weight ratio should be satisfactory and a fun little hot rod to play around with.

Your son's and your 300 inline project sounds great. As sixes go, I've always liked the Ford 300. If I had some 300's as readily available as the three 200's I already have, I'd be using the 300. It's a great choice.

Best wishes.
03-18-2012 01:21 PM
Augusto
Quote:
Originally Posted by RetiredHotRodder
Hi Chris,

It sounds like we're doing about the same type of hot rod project, using a six cylinder and wanting to adapt 6 motorcycle carburetors or just 6 carbs. I'll tell you a little about what I've found out so far. Maybe we can help each other as we go along.

I always like a totally different type of hot rod, something that not everyone else is doing, just for the fun of doing it. My last T Bucket was powered by a 427 set on kill. This one now with the six, is something for a totally different reason ... just to see if I can do it and hope it turns out as well as I imagine it will.

I'm making my frame from round d.o.m. tubing, my own aluminium 23 T style body and a six banger with 6 Mikuni carbs. Everyone uses a V-8, but a Six in an old T hot rod seems to get more interest. Plus, if the combination of parts is all matched properly, there's nothing that sounds quite as cool as a hot six banger when at high rpm's.

The engine I'm using is a 200 cubic inch Ford inline six with the intake and exhaust cast as part of the head. That aspect of this engine seems to be one of its Achilles heels. To me it sounds like a fun challenge.
I'm a retired machinist and welder so the head-work needing to be done, I can do here in my garage. I don't know if your Pontiac has the intake and exhaust cast into the head like my Ford does.

I'll just mill cut and mill the intake runners down flat with anything else in that area. Then make my own intake manifold from about a 3/4" plate, then weld the same size tubes to match the Mikuni carburetor and attach the carbs to the new intake runners the similar to the way they were attached on the bike. I believe these carbs are about 36mm.
Then drill and tap the side of the engine making sure not to drill into a water jacket or anything, then use screw-in studs with some good adhesive on the threads for the intake plate to fasten to. That's the plan now but sometimes plans can be subject to change.

There's been allot of questions by others about doing this project or a very similar type of project. The main question they have is about how to properly keep the carbs all tuned. I'm learning as I go on this particular project and often times that's just the way we have to learn. But if the tuning of these multiple carbs is anything like the other multiple carbs on my other hot rods, a good vacuum gauge is the trick. I am thinking that I may even need to install six smaller vacuum gauges - one vacuum gauge per intake runner. Welding a bung up above the runners so the bungs don't interfere with the intake flow. On my other hot rods I've found the value of tuning an engine with a vacuum gauge works wonders!

On most of my cars I've installed a large faced vacuum gauge inside the car under the dash and I also mounted a smaller faced vacuum gauge under the hood into a threaded hole in the intake manifold. This has worked wonders on the tuning of a Holley 4-barrel 390 cfm on an Offenhauser intake and home made headers on my AMC Eagle with the inline 258 six cylinder. It's amazing how much closer I can put a good tune on an engine with the addition of a vacuum gauge or gauges.

A computer would be able to keep a modern system like this tuned constantly but when building an old school hot rod I just prefer to leave the computers in my newer cars, and keep a tool box handy, just my opinion. So to make the tuning last longer I'm going for the vacuum gauges to help me keep everything tuned and to tell me when something is starting to go out of tune so I can make the adjustment before it becomes a big problem.

I realize going into this project the complexity of using six motorcycle carburetors for this engine and I'm okay with it. I'm prepared to make adjustments more frequently than I would on something else. But I really like the coolness about using a hot six banger with six carbs in a 1,000 pound hot rod.

Let me know how your project is going. Like I said, maybe we can help each other as we go along.

Best wishes!
not to question your project, but why doing all that machine work for only 200 cubes? I would use a 300 cid (also known as the 4.9) inline six ford that has external intake and exhaust manifolds? plus the 100 extra inches will give you a much rewarding engine, and with the six carbs it would just look awsome.
I'm already installing an I6 300 in my son's granada, look at my pictures, or the thread I started for it :

http://www.hotrodders.com/forum/ford...da-205602.html
03-18-2012 07:46 AM
boatbob2
slight subject change...

Hi,i was at Big Daddys (Don Garlits) anti-billet, rod show yesterday,just South of Ocala,fla,there was a car there with 8 SMALL TURBOS,turbos were mounted right in the header pipe,very close to the head,maybe 1 to 2 inches from head.,kinda neat,but i didnt have a chance to talk to the owner.nice engineering...
03-18-2012 04:26 AM
cobalt327
Quote:
Originally Posted by beertracker
My first thoughts are how much CFM does the engine require to operate? I suppose you could take the CFM required and divide by 6 therefore you have each single carb CFM requirement.

Did Pontiac use a variable CFM Q-jet on this engine? Sounds like a interesting project.

BT
The Sprint engine used a 750 CFM, side fuel inlet carb, much like what you'd expect to find on a SBC, except some Sprint Q-jets had the cutaway secondary air valve flaps seen on some (mainly Pontiac) V8 carbs. My original '68 Sprint had the the cut out flaps, I've seen other Sprint engines that had solid air valves- although I do not have any way of knowing if the other carbs were original or not.

Some carb number info:
1969- 7029260(AT), 7029261(MT)
1968- 7028260(AT), 7028261(MT), 17054906(?typo prolly?)
1967 (230cid) - 7027268(late, AT w/o AIR), 7027269(late, MT w/o AIR), 7037268(late, AT w/AIR), 7037269(late, MT w/AIR) [7027260 (early, AT w/o AIR), 7027261 (early, MT w/o AIR); 7037260(early, AT w/AIR; 7037261(early, MT, w/AIR)
1966- 7026260(AT), 7026261(MT)]
(info inside brackets from HPP magazine)

Besides the Q-jet carb and intake, the OHC Sprint engines had a bigger exhaust valve, higher compression and more cam lift and duration along w/dual valve springs and a split exhaust.

03-17-2012 11:46 PM
beertracker My first thoughts are how much CFM does the engine require to operate? I suppose you could take the CFM required and divide by 6 therefore you have each single carb CFM requirement.

Did Pontiac use a variable CFM Q-jet on this engine? Sounds like a interesting project.

BT
03-17-2012 11:31 PM
RetiredHotRodder Hi Chris,

It sounds like we're doing about the same type of hot rod project, using a six cylinder and wanting to adapt 6 motorcycle carburetors or just 6 carbs. I'll tell you a little about what I've found out so far. Maybe we can help each other as we go along.

I always like a totally different type of hot rod, something that not everyone else is doing, just for the fun of doing it. My last T Bucket was powered by a 427 set on kill. This one now with the six, is something for a totally different reason ... just to see if I can do it and hope it turns out as well as I imagine it will.

I'm making my frame from round d.o.m. tubing, my own aluminium 23 T style body and a six banger with 6 Mikuni carbs. Everyone uses a V-8, but a Six in an old T hot rod seems to get more interest. Plus, if the combination of parts is all matched properly, there's nothing that sounds quite as cool as a hot six banger when at high rpm's.

The engine I'm using is a 200 cubic inch Ford inline six with the intake and exhaust cast as part of the head. That aspect of this engine seems to be one of its Achilles heels. To me it sounds like a fun challenge.
I'm a retired machinist and welder so the head-work needing to be done, I can do here in my garage. I don't know if your Pontiac has the intake and exhaust cast into the head like my Ford does.

I'll just mill cut and mill the intake runners down flat with anything else in that area. Then make my own intake manifold from about a 3/4" plate, then weld the same size tubes to match the Mikuni carburetor and attach the carbs to the new intake runners the similar to the way they were attached on the bike. I believe these carbs are about 36mm.
Then drill and tap the side of the engine making sure not to drill into a water jacket or anything, then use screw-in studs with some good adhesive on the threads for the intake plate to fasten to. That's the plan now but sometimes plans can be subject to change.

There's been allot of questions by others about doing this project or a very similar type of project. The main question they have is about how to properly keep the carbs all tuned. I'm learning as I go on this particular project and often times that's just the way we have to learn. But if the tuning of these multiple carbs is anything like the other multiple carbs on my other hot rods, a good vacuum gauge is the trick. I am thinking that I may even need to install six smaller vacuum gauges - one vacuum gauge per intake runner. Welding a bung up above the runners so the bungs don't interfere with the intake flow. On my other hot rods I've found the value of tuning an engine with a vacuum gauge works wonders!

On most of my cars I've installed a large faced vacuum gauge inside the car under the dash and I also mounted a smaller faced vacuum gauge under the hood into a threaded hole in the intake manifold. This has worked wonders on the tuning of a Holley 4-barrel 390 cfm on an Offenhauser intake and home made headers on my AMC Eagle with the inline 258 six cylinder. It's amazing how much closer I can put a good tune on an engine with the addition of a vacuum gauge or gauges.

A computer would be able to keep a modern system like this tuned constantly but when building an old school hot rod I just prefer to leave the computers in my newer cars, and keep a tool box handy, just my opinion. So to make the tuning last longer I'm going for the vacuum gauges to help me keep everything tuned and to tell me when something is starting to go out of tune so I can make the adjustment before it becomes a big problem.

I realize going into this project the complexity of using six motorcycle carburetors for this engine and I'm okay with it. I'm prepared to make adjustments more frequently than I would on something else. But I really like the coolness about using a hot six banger with six carbs in a 1,000 pound hot rod.

Let me know how your project is going. Like I said, maybe we can help each other as we go along.

Best wishes!

Quote:
Originally Posted by chrisinestes
I'm building a hot rod from the frame up. I'll be using a Pontiac OHC 6 for power. I thought it would look sweet having 6 MC carbs on it. I've done a ton of Googling on the subject and it's been done, but it's a tricky thing. Nobody I've talked to has actually done it themselves, they just have seen it done succesfully by somebody else. It seems the main problem is MC carbs don't have accelerater pumps and aren't designed to run with much fuel pressure at all. It's a budget build, so I can't just go buy 6 new Mikuni Harley Davidson carbs at $500 each.

Has anybody here done this, or know somebody who has? Any Ideas? They wouldn't have to be MC carbs, I'd just want 6 1 BBL carbs.

Thanks!
Chris

Quote:
Originally Posted by chrisinestes
I'm building a hot rod from the frame up. I'll be using a Pontiac OHC 6 for power. I thought it would look sweet having 6 MC carbs on it. I've done a ton of Googling on the subject and it's been done, but it's a tricky thing. Nobody I've talked to has actually done it themselves, they just have seen it done succesfully by somebody else. It seems the main problem is MC carbs don't have accelerater pumps and aren't designed to run with much fuel pressure at all. It's a budget build, so I can't just go buy 6 new Mikuni Harley Davidson carbs at $500 each.

Has anybody here done this, or know somebody who has? Any Ideas? They wouldn't have to be MC carbs, I'd just want 6 1 BBL carbs.

Thanks!
Chris
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