My 67 Chevelle 300

[Tazracing]

Re: My 67 Chevelle 300

the speedo cable is easy..

the heater core isn't bad..

[67pete300]

Re: My 67 Chevelle 300

Thanks Deucecoupe and welcome to Bangshift! My whole inline build was based off the info I got from the inliners site. I haven't been as active there lately because my interests are much broader than just inline stuff, but that is a great site and full of helpful folks.

I'm pumped about your hp predictions! I plan to cobble together a few Chevy air cleaner decals to get "250 Turbo Thrift, 250 Hp." Maybe a bit of a stretch, but maybe not once I get the exhaust done.

What did you learn about intakes and carbs with your testing? There was much debate over there about Clifford vs. Offy. And many people are inclined to think the Edelbrock 500 cfm 4bbl is too much carb for this engine but it is often used by the inliner crowd. I picked that over the Holley 390 just because it was so much cheaper!

[DanStokes]

Re: My 67 Chevelle 300

DeuceCoupe - welcome to the madness here with us BSers.

I'm running an Offy with a Holley 475 Truck Avenger, which is what Holley suggested as the "right" carb. The dyno guy and I determined it was WAY too rich and I ordered a bunch of little jets. Runs great now. I'm also running a fairly mild Delta cam and Hooker headers, which have been a real pain to get sealed to the head.

I LOVE messing with the 250 and I look forward to your input on the site.

Dan

[DeuceCoupe]

Re: My 67 Chevelle 300

Pete,
Here is the Inliners thread from when I did the 250 intake/carb shootout:

http://www.inliners.org/ubbthreads/ubbthreads.php?ubb=showflat&Number=61079#Post61079

As far as carb size / CFM I noticed NO correlation.
This engine was making about 170hp max, so with my "double your horsepower" method for sizing carbs, it probably wanted about 340cfm. All the carbs were bigger than that, but beyond that there was no correlation with how they ran.

For example, here are the top 7 runs from a weighted average of metrics (of 59 total runs!!!!!!!!!!!!!!!!):
Intake - CFM&Carb - 60ft - 1/8ET - 1/8 MPH
1. Clifford - 610cfm AFB 1406 - 2.580 - 11.266 at 62.4
2. Offenh - 450cfm Holley 4548 - 2.582 - 11.238 at 62.5 ;D
3. Offenh - 500cfm Autolite 1.12 - 2.630 - 11.324 at 62.2
4. Clifford - 390cfm Holley 6390 - 2.585 - 11.318 at 62.9 ;D
5. Offenh - 390cfm Holley 6390 - 2.574 - 11.284 at 62.3
6. Clifford - 450cfm Holley 4548 - 2.601 - 11.405 at 62.7
7. Offenh - 470cfm Rochester 4gc - 2.644 - 11.390 at 62.3

Those top 5 runs are too close to call.
There was no correlation of CFM or intake (Offy vs Clifford) overall. Offy a bit stronger down low, Clifford a bit stronger up high. This is on a Nova, just under 3100 lb with me in it, thru a stock stall ~1700 converter 1.82 Powerglide and a 3.08 gear.

To show you how much variation there was in carbs and tuning:
Box-stock Autolite 4300 1.00, 470cfm
2.664 - 11.856 at 61.0
Jet Change, up 5 sizes
2.627 - 11.595 at 62.2
That's over a quarter second in the 1/8 mile (almost .4 sec in the 1/4 mile) from a jet change up from factory jetting.

As far as Edelbrock AFB carbs, the 1406 ran great out of the box even tho it is way too big. I suspect the secondaries were barely opening at all, or maybe just using the secondary transition circuit and air to give 300cfm or so. Would your Edel 500cfm respond to tuning? Hard to say but Edel offers a nice tuning kit, lots of metering rods etc for when you get to that point.

[67pete300]

Re: My 67 Chevelle 300

Got the Chevelle out for a late fall cruise and the first accompanied cruise with the new engine. My wife says, "It smells different now." I told her that now it smells like oil cooking on the exhaust manifold instead of unburned gas and other sludge coming out of the exhaust. ;D

I messed around in the parking lot while the girls played on the playground...

[Brian Lohnes]

Re: My 67 Chevelle 300

Man, that car is too neat!!!

Well done Pete, I'm waiting for the day when I get to have the photo of the family piled into Goliath!

Great to see it out and about on a nice fall day! (I was laying in a puddle of brake fluid but was with you in spirit. :D )

Ol' Goliath needs plenty of time to warm up on days like today. How 'bout the Chevelle? I can drive the truck with it partially choked until it is up to operating temp, but it isn't really happy until it gets fully warm.

Brian

[Gravy Boat]

Re: My 67 Chevelle 300

Very Cool Build - I have a super charger kit for a straight six - if your interested? I had it on 235 in 55 Chevy short box step side! let me know.

[67pete300]

Re: My 67 Chevelle 300

Man, that car is too neat!!!

Well done Pete, I'm waiting for the day when I get to have the photo of the family piled into Goliath!

Great to see it out and about on a nice fall day! (I was laying in a puddle of brake fluid but was with you in spirit. :D )

Ol' Goliath needs plenty of time to warm up on days like today. How 'bout the Chevelle? I can drive the truck with it partially choked until it is up to operating temp, but it isn't really happy until it gets fully warm.

Brian

I read of your success today, so just get Goliath legal and we'll meet up on the road somewhere.

The Chevelle starts up great now that it is all sorted out. I just leave it at high idle for a full minute or two and then kick it down and my newly wired up electric choke takes over. It idles nicely and warms up quickly.

[langleylad]

Re: My 67 Chevelle 300

Very nice , I love what your doing with it . But that has got to be one of the ugliest licence plates ever made , it belongs on a tank . Keep up the good work .

[TheSilverBuick]

Re: My 67 Chevelle 300

Looks great Pete! Glad to hear it's purring down the road.

[CTX-SLPR]

Re: My 67 Chevelle 300

Great to see a family including car seats in classic car. I'd really love to get my hands on a Buick crew cab A-body of this generation and use it as the family cruiser.

Interesting thought on a Supercharger for the I6. Jag made a supercharged 4.2L I6, bet it would be well sized for a 250.

[milner351]

Re: My 67 Chevelle 300

The supercoupe tbirds used an eaton M90 as I recall - 90 is for 90 cubic inches of air moved per rotation as I recall.

[CTX-SLPR]

Re: My 67 Chevelle 300

The supercoupe tbirds used an eaton M90 as I recall - 90 is for 90 cubic inches of air moved per rotation as I recall.

I think the early ones used M62's as did the early GM L67's but the Ford unit is set up for use with an external intercooler or at least ducting. The Jag I think is also an M90 but it's set up for an I6 so the drive snout might be longer or something. Relatively rare though as I think it's a 94-95 XJR only item.

[67pete300]

Re: My 67 Chevelle 300

I appreciate all the ideas, but there are a few items on the list before a power adder. Like changing out the 40 year old original shocks ;D

[std]

Re: My 67 Chevelle 300

Very nice , I love what your doing with it . But that has got to be one of the ugliest licence plates ever made , it belongs on a tank . Keep up the good work .

Are you kidding? I love those plates....Are they 1967 plates. Can,t see the small print