Another summer, another project for the Inline Six

[jzjames]

I try to keep working on this truck to keep it going. Picked up an Offy-C intake for it a while back, and a Ford Motorcraft 2bbl (1.08) carb off ebay. Collected the parts; 2bbl to 4bbl adapter, throttle linkage for the gas pedal, a manual choke from the junkyard, and last week started this upgrade for my Inline Six. Time consuming (because Im slow), but I got it in there heres the pics.

Out with the old poor flowing log intake. It had a Holly 1bbl on it which never gave me any complaint.

I bought a set of studs and brass nuts for the intake mounting, this was a suggestion by someone on Fordsix Performance forum. Looks good so far, here's the Offy C getting mounted. Slow and deliberate. Patience - try to do it right the first time.



The 1.08 casting Motorcraft 2bbl that is recommended for the 4.9 litre motor, bought used off ebay for $50. Manual choke fixture that was a gift from my local junkyard, Airport Auto Wrecking! R.I.P.

And a cheap air cleaner, $20 @ Napa, hoses, choke cable and odds and ends getting buttoned up.


There's quite a difference in driving, my shiftpoints on my C4 auto transmission is now where they should be (I dont know why - vacuum signal?). The freer flowing intake is giving better power on takeoff, and at highway speed, and I am hoping the gas mileage will be as good as the 1bbl, hope it will be better! Happy camper!! (That may be my next project!)

[sargentrs]

Good job! Very nice.

[motzingg]

Hey!! NICE WORK.

I'm trying to do something similar by modding the log head. What jets did you end up with? I'm probably going to swing by napa on the way home and try to find that air cleaner. I gotta order jets though so i'd rather not order 5 sizes to fine tune, maybe just 2 or 3 sizes.

How is the cold start, warm up, etc without a heater in there?

"Time consuming (because Im slow)"

I've been off the road for 4 weeks now hacking a hole in my stock intake so don't feel bad! At this point i've probably got 20 hours into the damn thing having screwed it up several times and re-do.

[jzjames]

I browsed your project, modifying the stock intake.
You have seen this adapter from Summit?
http://www.summitracing.com/parts/trd-2044

[motzingg]

BOOOOORRRRING!

Ha ha, just kidding. If there is an easy way to do something I always like to do it the way that is twice as expensive and takes 10 times as much effort. Shoot, if the billet of aluminum hadn't been in the scrap pile at work, i probably would have spent $40 on that alone!!!

Seriously though, I was going off the numbers from dyno testing that 'classic inlines' have done. The 2v adapter gives you minimal gains and the 2v conversion is pretty significant. They said 27 hp improvement over the 1v whereas the 'adapter' only made 9 or so over stock. Plus i cant imagine that carb will like running down into a tiny hole, my 'converted' manifold opens up to the full size of the runner which is about 1.5" ID going in either direction.

I looked at the jets and motorcraft was actually smart enough to label them in thousandths of an inch bore... awesome! I have some jet drills that i can use to mod the stock jets until i sort out the tuning, then buy whatever jet size i end up with. It looks like the jets are $5 each!! Having to buy two per, each jet change will cost $10, it would be like $50 for me to go from a 40 to a 65 which is the range i'm thinking i'll be in.

I'm very close to being finished, will update the project thread once its done!

[motzingg]

BOOOOORRRRING!

Ha ha, just kidding. If there is an easy way to do something I always like to do it the way that is twice as expensive and takes 10 times as much effort. Shoot, if the billet of aluminum hadn't been in the scrap pile at work, i probably would have spent $40 on that alone!!!

Seriously though, I was going off the numbers from dyno testing that 'classic inlines' have done. The 2v adapter gives you minimal gains and the 2v conversion is pretty significant. They said 27 hp improvement over the 1v whereas the 'adapter' only made 9 or so over stock. Plus i cant imagine that carb will like running down into a tiny hole, my 'converted' manifold opens up to the full size of the runner which is about 1.5" ID going in either direction.

I looked at the jets and motorcraft was actually smart enough to label them in thousandths of an inch bore... awesome! I have some jet drills that i can use to mod the stock jets until i sort out the tuning, then buy whatever jet size i end up with. It looks like the jets are $5 each!! Having to buy two per, each jet change will cost $10, it would be like $50 for me to go from a 40 to a 65 which is the range i'm thinking i'll be in.

I'm very close to being finished, will update the project thread once its done!

[jzjames]

Used to be not that long ago you could pick up the Offy intake for like $200 shipped from JCW. Now it is expensive.
Ive always avoided jets change-outs, and changes from factory stock in general, but in the case of the inline six, the Offy intake was a no brainer. I cant get over how easily the changeover went, and just slapping on the Motorcraft 2bbl worked great from the get-go. Much better low-end torque. Better on gas I believe!! Hell, its almost like a Toyota!!

I'll be interested to hear how your mod of the stock intake works out, but jet sizes/calculating to me is B O R I N G !!! haha. Only because I know nothing about that stuff. Just hope its not an endless can of worms for ya.