Tricked-out Chevy six cylinder engines

[TJ's Chevy]

Originally Posted by Husein-p

in ur opinion l6-250 engine with 4bbl holley carb + Headers + Lumping port How much horsepower can deliver ?
with standard cam shaft ....

All depends....
I can give an estimate. lol

With a 390 holley, headers(any kind), HEI and a lump port head with 1.86 intake valves and stock exhaust valves I'd say about 40 more hp than stock....so close to 170-180 hp I think. I don't remember the hp specs on the 250's as of now. You'd really be wasting time not adding a little more lift on the cam at least. I'd go a step over stock with a cam if I was doing a light build. Comp cams has some good grinds for cheap.

[62 Barnfind]

235 bored 30 over, performance cam, Offenhauser duel intake and two Carter Weber Carbs.

[Husein-p]

Originally Posted by TJ's Chevy

All depends....
I can give an estimate. lol

With a 390 holley, headers(any kind), HEI and a lump port head with 1.86 intake valves and stock exhaust valves I'd say about 40 more hp than stock....so close to 170-180 hp I think. I don't remember the hp specs on the 250's as of now. You'd really be wasting time not adding a little more lift on the cam at least. I'd go a step over stock with a cam if I was doing a light build. Comp cams has some good grinds for cheap.

well
so i think with a good street cam like 0.490 valve lift and duration at 050 212 and lobe 110 can deliver 250 horsepower ! is this true ?

[TJ's Chevy]

Originally Posted by Husein-p

well
so i think with a good street cam like 0.490 valve lift and duration at 050 212 and lobe 110 can deliver 250 horsepower ! is this true ?

With that amount of lift and duration you'll be in the 255-270 advertised duration area. At that point you'll also want better, lighter pistons because the engine characteristics will be Completely different. Here's a build I would recommend.

Head work:
1.86 intake valves
1.60 exhaust valves
Be sure to have a at minimum 3 angle valve job and make sure the bowl is opened up as well. No chamber relief will be required.
Lump ports.
Z/28 valve springs.
.030 shave off the head.

Block work.
.040 over forged aluminum flat top pistons. Ross is a good place to check. Tom Lowe does sell them for cheaper. Those will give you about 9.5.1 compression.
A good cam would be comp cams 268H 218@ .050 .499 lift on a 110 lobe center. That'll give you a choppy idle and good RPM range. Here's the cam spec number 61-244-4. Go to their sight and see their camshafts. They have some nice options. Custom grinds are available as well.
Stock rods balanced and refitted with ARP studs and bolts.
Crankshaft balanced and ground for sure.

Add a good intake and headers will a 390 holley or 500 edelbrock and HEI. You should see around 290 hp and 270 torque.

Larry aka Twisted 6 can give you some options as well. He's on this forum once in awhile.
Tom Langdon at Langdon's stovebolt will also have good advice.
Mike at Ravenswood Paint and Body.....hard to get ahold of but a good man as well. lol
Tom Lowe has done dyno testing so you could probably get some specs from him.

[Slow Build]

I saw this in a CL ad. Thought I'd share.

[TJ's Chevy]

That's really cool!

['68OrangeSunshine]

Originally Posted by Slow Build

I saw this in a CL ad. Thought I'd share.

Barracuda aspirated!

[Texas1963]

Just received my offy 2 carb manifold for my 230 from speedway. It appears that there is no way to use any of the original linkage. The installation instructions are very vague. My question is has anyone here have this set up or seen it? The instructions for the linkage kit says to connect it to the original bell crank but that was connected to the original manifold and the offy has no provisions to install the bell crank set up. I thought it was going to be a simple swap out. thanks for any info.

['68OrangeSunshine]

Originally Posted by Texas1963

Just received my offy 2 carb manifold for my 230 from speedway. It appears that there is no way to use any of the original linkage. The installation instructions are very vague. My question is has anyone here have this set up or seen it? The instructions for the linkage kit says to connect it to the original bell crank but that was connected to the original manifold and the offy has no provisions to install the bell crank set up. I thought it was going to be a simple swap out. thanks for any info.

I converted to Throttle Cable on my '68 C/10 Stepside w/L6 292 and single 4 Bbl Edelbrock 1404 [originally it was on my Holley 390.]
Dual Carb or 2 barrel? Dual carbs may pose a challenge above my pay grade.

Or you could fab a pivot on the Offy like the one the cast iron GM intake. Not sure how.

[TJ's Chevy]

Originally Posted by Texas1963

Just received my offy 2 carb manifold for my 230 from speedway. It appears that there is no way to use any of the original linkage. The installation instructions are very vague. My question is has anyone here have this set up or seen it? The instructions for the linkage kit says to connect it to the original bell crank but that was connected to the original manifold and the offy has no provisions to install the bell crank set up. I thought it was going to be a simple swap out. thanks for any info.

Should have Some provision for the original bell crank. I believe it was on the Front of the manifold for some reason. The setup should be Similar to this.

https://www.youtube.com/watch?v=evcz4k1vjwQ

[ncoonen]

Can you point me to details on how you did this? (Pictures, part#s, etc.) I am about to drop a 292 with the same carb on a Clifford intake in my '63 and have been thinking about throttle strategies. A cable setup sounds much simpler than some of the fab'd-up mechanisms I have seen.

Many thanks...ned.

EDIT: I found this thread that answers about all my questions. Thanks TJ! Great work

Originally Posted by '68OrangeSunshine

I converted to Throttle Cable on my '68 C/10 Stepside w/L6 292 and single 4 Bbl Edelbrock 1404 [originally it was on my Holley 390.]
Dual Carb or 2 barrel? Dual carbs may pose a challenge above my pay grade.

Or you could fab a pivot on the Offy like the one the cast iron GM intake. Not sure how.

[Palf70Step]

How about this
https://www.carbsonly.com/carbs/dualrochestercarbs.htm

[TJ's Chevy]

Originally Posted by ncoonen

Can you point me to details on how you did this? (Pictures, part#s, etc.) I am about to drop a 292 with the same carb on a Clifford intake in my '63 and have been thinking about throttle strategies. A cable setup sounds much simpler than some of the fab'd-up mechanisms I have seen.

Many thanks...ned.

EDIT: I found this thread that answers about all my questions. Thanks TJ! Great work

Glad I could help. The Lokar setup is Very simple but fairly spendy. It was a littler over $100 when I bought my pedal, cable, and cable to carb mount. But I never had any issues with it, also it was Fully adjustable.

[Texas1963]

Originally Posted by TJ's Chevy

Should have Some provision for the original bell crank. I believe it was on the Front of the manifold for some reason. The setup should be Similar to this.

https://www.youtube.com/watch?v=evcz4k1vjwQ

Yes it does have the provision on the front of the manifold. I might have to get creative to set it up and thanks for the help.

[Texas1963]

Originally Posted by Palf70Step

How about this
https://www.carbsonly.com/carbs/dualrochestercarbs.htm

yes the manifold came with that linkage kit but no bell crank. I'm going to look at it closer today and thanks.

[GMDad]

I left the original pedal and arm and then made up some short rods to go to the original bellcrank that I mounted sideways. Fabricated a mount off the back of my Edelbrock carb. Been on there for about 10 years now and works perfect. No bad spots in the pedal just nice and smooth.

[Texas1963]

I think I'm going to send the manifold back and cut my losses unless someone has this set up already operational. If my truck was 3 on the tree it might be easy to set up a cable linkage but with the power glide and kick down bell crank. Nah! Someone has to be running this manifold. the only thing that would make this thing work is to weld a piece off tubing onto it to provide the pivot point for the original bell crank set up.

[ncoonen]

Originally Posted by GMDad

I left the original pedal and arm and then made up some short rods to go to the original bellcrank that I mounted sideways. Fabricated a mount off the back of my Edelbrock carb. Been on there for about 10 years now and works perfect. No bad spots in the pedal just nice and smooth.

Your pictures a very helpful. Thanks! The mount coming from the back-side carb studs is the key. Well done.

...ned.

[sambrutay]

Saw this one this weekend at Goodguys in Bowling Green Ky

[ncoonen]

Originally Posted by TJ's Chevy

Glad I could help. The Lokar setup is Very simple but fairly spendy. It was a littler over $100 when I bought my pedal, cable, and cable to carb mount. But I never had any issues with it, also it was Fully adjustable.

TJ - One thing you mentioned in your video was to be sure to get the billet aluminum pedal with offset trunnion. Can you explain why that is essential? I would prefer to use a black steel Lokar pedal with the XL foot pad if I go cable route. Like the XSG-6016


I really like the clean simplicity of the cable setup.

...ned.

[mehoff400]

heres my start to a tricked out 250

[Pappyx3!]

Mehoff400,

Just curious what's your build plan is? Just started tearing my 250 down for a winter rebuild. Planning on building one with a little attitude as well.

Thanks,

Pappyx4!

[TJ's Chevy]

Originally Posted by ncoonen

TJ - One thing you mentioned in your video was to be sure to get the billet aluminum pedal with offset trunnion. Can you explain why that is essential? I would prefer to use a black steel Lokar pedal with the XL foot pad if I go cable route. Like the XSG-6016


I really like the clean simplicity of the cable setup.

...ned.

There's two available with That particular trunnion....one offset and one in the center....I recommended the offset one as it allowed for more pedal travel And with that particular trunnion you don't Have to use a spacer. I would recommend a spacer though as it helps give a firmer base for the pedal.

[mehoff400]

Originally Posted by Pappyx3!

Mehoff400,

Just curious what's your build plan is? Just started tearing my 250 down for a winter rebuild. Planning on building one with a little attitude as well.

Thanks,

Pappyx4!

its has been stock rebuilt.. i plan on dual carbs and headers.. maybe cam and stuff later but dont want to dig that deep into the pockets

[slepysal]

mine with new disc brake booster