Well, for the past year I've been gathering parts for a conversion to dual carb / split exhaust. (pictures below) The stock 230 CID on this 137 VIN car was in great shape but I wanted a bit more visual appeal and sound to it. This week, while on vacation I did the surgery and removed the original 'strangulation intake' and 'constipation exhaust'. Now, after suffering skinned knuckles, burned arms, toxic exhaust fumes and a whopper bill from a muffler shop to custon bend the pipes from the manifolds back- the job is done. There is a new Offenhauser dual intake, Rebuilt Carter YF single barrel carbs, and Langdon cast iron split exhaust. It also has the Offenhauser finned side covers and valve cover, and Cal Custom chrome air cleaners. The air cleaners needed to be cut down in thickness to allow clearance under the hood.
The tricky parts were to file and grind the intake to allow it to fit in the same space as the power steering pump and integrated exhaust flanges. Also the linkage had me buffaloed on how to get the Powerglide rod and gas pedal rods to still fit on the stock bellcrank. That took about four hours. I still am making adjustments to tuning the carbs, but it is a LOT easier and quieter now that the exhaust pipes are made. I about knocked myself out with the direct fumes coming out of the shorty headers while getting it to run for the first time. And my ears are still ringing.
The fun part was driving it on open headers to the muffler shop in the next town. That 'ol six banger is plenty loud under acceleration.
So far I can say that it does have more power, and I can report back on fuel economy in a month or so. I'm told this set-up from single carb to dual shouldn't increase fuel use since the engine is breathing more effectively.
Can't wait to open the hood at the next cruise night!!! What do you think? Any suggestions on how else to detail under the hood or anything? I value all comments.
Tom

Time well spent. I'm sure no one else will have an engine like yours. Very nice. You must have spent a lot of time on the whole car. It's beautiful. I'm sure you are very proud of your ride. When you open the hood I bet jaws will drop and a croud will gather around your car. Very very nice.
Tom

Nice job. Where did you get the intake and split exhaust? Back in the day I ran a 39 chev. with a 55 6 banger with 3/4 cam, Ellis split intake with 2 - 2 barrel carbs and fenton headers.

I got the majority of the parts from Langdon's Stovebolt in Michigan. The valve cover came from Speedway Motors. Tom Langdon has been at it with the inline sixes for many years, and was a great source of information and help.
I bought some parts last year (Rochester carbs and steel tube exhaust) from various sources that I thought would work, but it wouldn't all fit and play nice without major modifications.
Langdon's was able to set me straight and he has most of the stuff you'll need to do a "buzzin' half dozen" in his catalog.
My exhaust now has that buzzin' sound to it like I hoped it would and probably about a 15% better acceleration over the single carb set-up. It has the stock cam.......I'll wait till the financial dust settles and then when the wife isn't looking I'll upgrade that next ;)

Very CLEAN & Well Done Job - Most Impressive thing is NO Autozone or the likes Battery

Always get a chuckle when looking under the hood of a chevrolet "showcar" and see a non-delco battery

Very nice:thumbsup: I love the detail:yes: Great job

Very Nice! I always stop and look at the 6cyl contingent @ the Car Shows.

Very CLEAN & Well Done Job - Most Impressive thing is NO Autozone or the likes Battery

Always get a chuckle when looking under the hood of a chevrolet "showcar" and see a non-delco battery

Thanks for the compliments.
I have to admit that the battery is a non-Delco. I had a perfectly good Napa one laying around and didn't want to spend the $140 or so for a reproduction. Heck, I didn't even want to spend the $70 or so on the fake slip-on cover that is available. So I bought a set of yellow caps and cut them down and epoxied them on the top. Then I bought the 4" x 6" 'Delco' reproduction side decal and put that on the front of the battery. I did that last year and so far only a few sharp-eyed folks have pointed it out, but thought it was clever after I told them how much a repro goes for. The yellow caps and decal came from E-Bay and cost about $20 total with shipping.
I'll be watching the catalog places and if those repro batteries ever go on sale..........

Very nice! One of the best I have seen!!!!

Looks even better with todays gas prices

I-6s rule. my 29 1/2 Pontiac is a split flathead inline 6. each head covers three cylinders. Amazing how many people that that all 6 cylinders are V-6s even a I-6 in a pre-2007 Jeep is advertised as a V-6 by many sellers and even dealers. LOL.

Tom
I really like what you have done:thumbsup: That combination looks real sharp. It will keep you very busy at the cruise ins, and shows. As nobody will be able to walk by without questions, and comments. Great job!

My 64 malibu came from the factory with a six cylinder. I bought the car with a 350. I found this out when I decoded the vin in the door. Your car is a beauty! Really nice.

WOW! I'm a V8 man but what you have build is way cooler than all my V8's!
That is a work of art, my hats off to you. Well done.

'Dare to be Different' - and you have :thumbsup: Looks great! You will get WAY more comments about that than if it was your run-of-the-mill small block :D

Great looking engine!

I have one suggestion. It looks as if the rubber in your power steering pressure line is curling around the exhaust manifold. Unless the perspective of the first photo is throwing off the actual closeness of the rubber to the exhaust, I would suggest a 90 degree bend right after the pressure line pipe leaves the pump discharge.

Jim

Love it!

Great looking engine!

I have one suggestion. It looks as if the rubber in your power steering pressure line is curling around the exhaust manifold. Unless the perspective of the first photo is throwing off the actual closeness of the rubber to the exhaust, I would suggest a 90 degree bend right after the pressure line pipe leaves the pump discharge.

Jim

Hi Jim,
you are right.....it is a bit close and should be routed further off like you suggest. I'll do that next. Thanks! Tom

Very nice! You should be proud of what you have accomplished.

That is one nice six banger!!!!!!!!!

Excellent work, looks great

Thats a sweet lookin' six you have there! Always nice to see something underhood you dont expect. Nice work!:beers:

Got any before pictures? The final result looks great.

i just finished a 6 cylinder restoration myself, nowhere near done but i did the best i could with the motor in the car, it will come out some day:thumbsup:

How do you like those headers? I was going to get a set for my car but ending up running a single through a magnaflow muffler, sounds a fart can civic from behind the wheel but apparently it sounds pretty good going by.

http://i35.photobucket.com/albums/d184/photothing2006/P1010214.jpg

http://i35.photobucket.com/albums/d184/photothing2006/P1010579.jpg

that look great, thats how they should have been built from the start............ :)

Hi ,

I just love those six bangers , much better stuff than all those V8's

Could you tell us how much $$$ those Offy intakes go nowadays ?

Thanks !

Laurent

Hi ,

I just love those six bangers , much better stuff than all those V8's

Could you tell us how much $$$ those Offy intakes go nowadays ?

Thanks !

Laurent

Hi Laurent,

The aluminum offy intakes are available from Langdon's stovebolt and I think they cost $259 or so. Aside from having to trim the flanges to snug up to the exhaust flanges it fit the engine real nice. I also bought the coolant heat plate and have it installed underneath, but haven't hooked it up yet. The plate will allow the circulating engine heat to keep the intake warm and allow for good vaporization in cooler outdoor temperatures.
Tom

that look great, thats how they should have been built from the start............ :)

I fully agree Vince!!! :) :)

Got any before pictures? The final result looks great.

How do you like those headers? I was going to get a set for my car but ending up running a single through a magnaflow muffler, sounds a fart can civic from behind the wheel but apparently it sounds pretty good going by.


Hi T. Mac,

The Langdon's cast iron headers so far seem to be real nice. They fit real good and time will tell if the clean shiny appearance will remain. I'm told that they will last longer than steel tube headers.
I'll send you some 'before' pictures via a PM. I'm visiting a relative right now and will have to get home to access pictures. I'm five minutes away from good 'ol Canada in Fort Kent right now. Across the St. John river I can see Canada right now.
Tom

really enjoyed this thread. Nice to see a different look under the hood. At $1.50 per liter ($5 gallon) gas price I'm sure this will catch on!

Since you've modified the engine, why not just put a modern Delco battery in, available at you neighborhood A/C Delco outlet.

Way cool! I believe that you are right when you say that fuel economy shouldn't suffer with the dual carbs given the other efficiencies in the manifolding. One day you could sneak a 250 crank in there for added bottom end torque and cubes.;)

That finned Offy valve cover and lifter gallery cover look great for the overall theme.

Any trouble getting the carbs in sync? What are you doing for choke control on the YFs?

What are you running for an exhaust system downstream from the manifolds?

Okay.....speechless....:eek:

I know sonmebody who wants to copycat that thing o'yours

Wanna make an easy buck? ;)

Gotta have THAT in my 250....the longer I'm looking at the pump, the more I'm thinking to keep the 6 and just make something decent out of it.

The aluminum offy intakes are available from Langdon's stovebolt and I think they cost $259 or so.

Hi Tom ,

thanks for the input , I saw they also were available at Summit .

I asked this because I'm thinking to build a kind of a "Chris-Craft" runabout with a 250 in there , and such Offy ol'skool setup would be ideal for such craft .

Thanks ,

Laurent

Any trouble getting the carbs in sync? What are you doing for choke control on the YFs?

What are you running for an exhaust system downstream from the manifolds?

Hi Cam,

The carbs haven't been any trouble yet.
I installed each one separately on the stock intake just to get them close, so then when they went on the Offy they fired right up. I've only had to make some minor adjustments.

The exhaust is 2" all the way back, interrupted by a pair of flowmasters. One of the pipes crosses over to the passenger side just under the powerglide pan. I'd have to unbolt the manifold flange and let the pipe drop out of the way when the time comes to drain the fliud and replace a transmission gasket. But there is a ton of clearance everywhere else.

I have a manual choke attached to the carb closest to the firewall. The other carb has the choke plate locked open. I read about doing this on the Stovebolt forum.
Tom

Okay.....speechless....:eek:

I know sonmebody who wants to copycat that thing o'yours

Wanna make an easy buck? ;)

Gotta have THAT in my 250....the longer I'm looking at the pump, the more I'm thinking to keep the 6 and just make something decent out of it.

Youri, how ya doing over there in the land of Tall Blondes??
Over here we have a saying...
"Imitation is the sincerest form of flattery"

So go ahead and do it! Keep the six in your '68, and spend about $1,400 (US) to get all the shiny and loud parts. They all just bolt on, except the exhaust pipes have to be custom-bent.
Most of the parts including the HEI ignition can be found at Langdon's website.
http://www.stoveboltengineco.com/

Take care Youri,
Tom

That is very cool in an old-school way. Nicely done.

JimL already beat me to the observation about the power steering hose, figures ;)

Myself, I always wanted to see side draft carbs on inline engines. But then I am probably showing my early British/motorcycle influence there too. Never understood why American cars always had to use a down draft carb and that forced 90* turn at the carb base. When Triumph stuffed a pair of SUs or Strombergs onto the side of a tractor motor and get fun performance AND 30 MPG, they must have done something right. There is a lot of power to be found in a good clean intake system.

That is very cool in an old-school way. Nicely done.

JimL already beat me to the observation about the power steering hose, figures ;)




Thanks everyone for all the great replies.

VROOOM3440: Today I was able to bend the steering hose steel line about 15 degrees away from the engine. It cooperated quite nicely without kinks or leaks. This now gives me about 3" clearance from the header.
I also added a fabricated bracket that serves as a more effective throttle return spring holder.

Next action....to look for a Delco reproduction battery.

Thanks again, Tom

Youri, how ya doing over there in the land of Tall Blondes??
etc...


Most of our people are enjoying in Switzerland right now :)

http://www.nrc.nl/multimedia/archive/00255/bundesplatz_255721a.jpg


Maybe I'll join them if they'll make it into the finals in Vienna :D

On-Topic:

I've already received your link earlier, I really needed the bit of extra power also because the car feels underpowered when i'm moving it out of position in it's first gear....guess the gearbox is a little too heavy for the engine. :)

WOW, is all I can say. I love the setup. Its refreshing to see something different for a change. You'll get lots of compliments on that set up. You should post a video of how it sounds when it is running. :thumbsup:

Its nice to see 6 cylinder engines detailed like that for a change. Very nice.

Just want to add my 2 cents... you did a great job with the car! Again, nice to see something a little different and so nicely executed. The attention to detail really helps set the car apart... NICE!!