When installing a new engine or even modifying your present power plant fuel and intake system you have a few things to consider.
Of course the size of your fuel pump, where it and the fuel filter is located, size of the filter, size of your fuel line, fuel pressure. Along with that jet size or injector size and baffling in your fuel tank. All of this is important to ensure your fuel delivery system can maintain full pressure at peak engine horsepower in high gear.
All of these need to be adjusted or “sized” to accommodate less controllable factors such as Altitude, air temperature and idiosyncracies of your fuel, like quality and octane rating. Yes even specific gravity of your gas can effect the jetting.
Here are some jetting requirement of a 750 CFM 4 barrel Holley for specific fuel, temps and altitude options:
Octane Temp. Altitude Front Jetting Rear Jetting
94 80F 0 ft 81 86
110 Race 80F 0 ft 81 83
94 80F 3000 ft 76 81
94 80F 6000 ft 73 77
94 40F 0 ft 84 89
94 120F 0 ft 78 83
Oxgenated fuels toss another factor in to be considered when determining your jetting requirements.
Studies of shown that every 1 point richer in air/fuel ratio equals only a few percent less power. Running the engine as lean as possible will increase your power but also increased combustion chamber temp, which can damage your engine.
1957 – 1958 saw the use of the New 283 engine in Chevy‘s including the Corvette.
The Corvette was fitted with the Rochester RamJet and RAM’s horn intake as the RPO Code 579D. But recently during some research I read that there was another modification.
It was called the Air Box Option, RPO 579E and it was perhaps the first production cold air induction system(at least for Chevy).
It consisted of a plenum box mounted on the fender well of the driver’s side. The box was fitted to an opening in the bulkhead next to the radiator with an air filter inside. The duck work ran to the fuelies injection unit.
Records indicate that there were only 43 produced in 1957.
So far my writings are about engines have been ones I owned and the 283 was the engine in my very first car. It was a 1966 Chevy Impala. It was a gift to me for my 1976 high school graduation. The car was restored by my father, who was a master auto body man. The car was a convertible with A/C and glass rear window. It sported an automatic Powerglide transmission.
The 283 was a simple engine and of course the engine bay of the ’66 Impala could hold a family of four, with lots of room to work in there. Oh…those were the days…a piece of cardboard on the ground and 3 bolts later you’d have the starter out. I wish I could find a picture, I know there were some taken, polaroids back then, but they’ve disappeared over the years, much like the car.
So what’s the history of the 283 and what was it used in. Well those answers are coming up as well as two special uses of the 283, one in the past and one modified restro-mod use…(yeah…someone mod’ed a 283..very cool, but that is later).
As with most engines the 283 wasn’t drawn up on the design boards and produced. It was a result of Chevrolet’s desire to increase performance of a power plant they already had on the shelf. The 265 cubic inch small block underwent transformation that resulted in a new engine in 1957.
The modifications made to the 265 to create the 283 were increased bore from 3.75” to 3.875″, the main bearing was given 2.30” journals and 2.00” connecting rods. The base configuration (with a two barrel carb) for the 265 produced 165 hp, the 283 made 185. Twenty more horsepower doesn’t seem much but toss on a 4 barrel and the 283 takes off at 220 hp which tops the 265 similarly configuration producing 185-195 hp.
Chevy's 283
1957 was a good year for Chevy. Bill “Grumpy Jenkings took a 283 fitted with a dual carb set up and achieved 270 hp. It was also the first year for Chevy’s Rochester Ram Jet and what better engine to use than the new 283. This combination took the 283 in to the history books by producing horsepower that equaled the displacement – 283 c.i.d. and 283 hp.
And that is what led to the installation of the 283 in Chevy sports car platform, the Corvette.
Unfortunately I have to start the year out with a legal notice. It seems that my writings are so inspiring(…ok…stop laughing!!!) that a few sites have decided that they would use them on their sites in total, placing ads in the middle for their profit and not requesting permission.
I enjoy writing my blog and I do it to share experiences and social interaction.
If you like it, great!!
If you’d like to share links, I’m all for it
If you want to post entire articles ask permission and I’ll send you my list of requirements for accomplishing this.
If you want to use my articles and place and in the articles, we need to talk first.
As we close out the year that was 2010, I celebrate the first year anniversary of Average Guy’s Car Restoration, Mods and Racing.
Over the past year, I’ve enjoyed jotting down my thoughts and experiences. Mostly, I’ve enjoyed hearing back from readers here on my Word Press main site and in other social media.
This past year I’ve seen the page views on this “one man” blog go from just a couple per week, to nearly 1500 a month. Not bad for a non-commercial blog, with no paid advertising. So THANK YOU. I hope to hear from and read your comments and views in 2011.
What’s coming up in 2011? Mods on the ’70 Mustang, tweaking of the LS2 on the 07 Corvette and I’ll continue with the Auto Factoids in their new format. You will see more mini engine series, kicking off the New Year one of my favorites Chevy’s 283 and there will be more racing events, test ‘n’ tunes and Mom and Pop racing teams highlighted. There will be more contests and DVDs to give away and project updates from readers. Oh…I’m coming out with the Average Guy’s 2011 Calendar look for that on-line.
It’s going to be a fun new year.
To you and yours – may 2011 bringing nothing but happiness and joy.
What you will see unfold in these updates is an exercise in project management for the modifications. When I originally scoped out the components for the 302 that replaced the 250, I used a similar process, but very detailed. I wasn’t overly concerned with improvements other than what a dropped in 302 would provide over that tired old straight 6. (Clearly..I left the 3 speed manual trans in it.)
But this time it’ll be different. There is a lot to do and unlike the previous rebuild, money will be tight and free time limited. The main goal I have is to keep the car in operation in between stages of modification. This will take a clear and well laid out plan, where issues similar to the installation of the dash pad before the pillar post trim arrived (doh!), could be more than just a cost in time.
Below is a high level sketch of what I’d like accomplish with the Mustang. I’ll update this list with more details as I figure which brands, sizes and the like that will be used. Over on my Facebook pages I have already received some feedback and suggestions and I’ll post these up here in some cleverly titled entry.
So give me your suggestions or opinions and as the progression goes even tell me if you don’t like the choice and why.
Brakes and Suspension:
– Upgrade to 4 wheel disc (Brand and size TBD)
– Replace front and rear stabilizer bars (Brand and size TBD)
– Control arms already replaced
– Rebuild power steering
– Shocks already upgraded
Exhaust:
– Add cut-out before mufflers
– Extend tailpipes to exit rear
No other changes anticipated
Interior:
– Addition of upgrade dash and interior lights
– Possible upgrade of all gauges
– Replace front seat belts with 3 point harness
– Carpet replaced
– Seats re-upholstered (upgrade to Leather/Cloth?)
– Paint lower doors
– Tilt steering wheel (Flamming River?)
Training:
Transmission
– Option 1 – Manual 4 speed with Hurts shifter
– Option 2 – T5 5 speed
– Rear Differential * Unsure if upgrade is possible or required
Engine:
* 302 stays
– Replace intake (Brand and size TBD)
– Replace 650 Holley (Holley 750 Avenger)
– Replacement of heads for more performance (undecided)
– Add custom mounting and tension for Power Steering/Alternator
– Remove Fan and replace with electric
– Add more chrome to engine (but not too much Bling..hate too much Bling)
Exterior:
Paint stays except:
– Blacked out rear light deck
– Black Hood stripe (1970 Boss 1970 302 or 1970 Mach 1) – See images below – What do you think?
– Blacked out grill
– Black Front Spoiler
– Black side Boss 302 Stripe (w/o the Boss) (dependent on hood choice)
– Magnum 500 wheels (newer version, not originals)
Hood lay outs:
Mach 1 Hood...Perhaps my favorite...currently not considering adding a scoop
Boss 302 Hood lay out
O.K., let’s hear your thoughts. They will automatically appear to the right of this posting and I’ll add the good ones in the update posts.
Thanks for reading.
Tim
Readers comments and suggestions:
Byron McElfresh December 6 at 9:09pm Report
I seen your asking for advice on heads for a 302. I built a 302 that was .040″
over bore, The larger hyd. roller ford performance cam, used edelbrock rpm
heads, i did a little clean up and evened out the valve bowls, flat top
pistons, a 750 holley Street advegner carb, rpm intake, 1 3/4″ headers, and it
made 416 hp at 6000 rpm, and 349 tq. on the dyno. in the 60 Falcon with 3.73
gears, and a 4 speed,( the guy really needs an auto trans or get a shifter that
won’t granny shift speed wise!!!) But he still ran a 12.61 at gateway.
Wow, that’s pretty good. My 302 is bore .030. Hooker headers and 65O holley. I
wasn’t planning on changing out the cam. Now the rear end great. I just can’t
do the automatic trans though!
Byron McElfreshDecember 6, 2010 at 11:43pm
Re: Hi Tim,the 302
lol-the reason I think the guy should o to an auto trans is the ultra slow
shifts he makes with the old toploader! It’s a very painfully slow 2-3
shift!!!You can almost hear the multiple double clutches! yikes! lol
Tim Sweet December 6 at 10:11pm
good point
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Philip Daly December 6 at 8:58pm Report
351w
Tim Sweet December 6 at 9:36pm
Thanks Philip, But won’t that reduce compression? How much would you gain with
351w heads?
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Terry Wallace December 6 at 8:47pm Report
Ford Motorsports usually has some really great deals on 302 old school engines.
I would check there first. When it comes to flow numbers im finding through my
own testing at my machinists shop,,,,,most numbers are bullshit. beware and
test flow numbers using a reputable shop.
Tim Sweet December 6 at 9:35pm
Thank Terry. I’m with you on the numbers game…happens a lot even with
Corvettes. Regards
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Bill Rice December 6 at 8:46pm Report
Trick Flow Twisted Wedge heads, Great gains in HP and Torque.
Tim Sweet December 6 at 9:42pm
Thanks Bill – what do you think those number might look like over a 302, bore
Corvette Hangout December 6 at 8:28pm Report
C&C aluminum heads with small chambers to get higher compression larger valves
and install 150 shot of nitros.. CorvetteHangout
Tim Sweet December 6 at 9:44pm
I can get behind the higher compression..but I haven’t decided on NOS yet.
Thanks.
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Fatherlarry Monaco
1969 and 1970 Boss 302 heards and intake will work great.
Tim Sweet That was a thought I had as well.
2 seconds ago · Like
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Roy Oberg Aluminum is the way to go, go with a smaller combustion chamber that will give you more compression and less chance of spark knock.
about an hour ago · LikeUnlike
#
Tim Sweet 100% on board with the smaller chambers.
2 seconds ago · Like
After much internal debate about what to do with my 70 Mustang I’ve decided on a direction for Mustang.
Running out of car projects (there was always something to ‘fix’ on the ’84 Vette). The 07 Vette is going to stay as if for a while, I like just it as it is for now. The Mustang is nearly done, with just a re-upholstery with the front seat, restoring the back of the rear seat and replacing the steering column cover and new carpeting. That’s all coming up soon. But there are a few more things that are going to happen. The time frame will be fluid given the availability of funds (Average Budget) and time.
I wrestled with keeping the car original in the beginning. But with the tired old 250 straight 6 wasn’t going to make it possible, coupled with my desire to have more horse power. I’ve often thought that the 302 swap wasn’t horrible and by keeping the 3 speed manual transmission, my changes didn’t reach the level of a resto-mod and I still think I’m good there. Keeping it period (swapping out items that were actually available for a coupe as options in 1970) I thought was noble in trying to bring it up to a level of performance I “could live with” without straying too far from its original configuration. However, I understand that a ’70 Coupe isn’t ever going to reach the value of any other ’70 model or configuration of Mustang nor will it receive a comparable level of the attention at car shows.
So I’m working out a plan for taking this under rated coup to an all new level.
Currently as configured the car has the following:
