Journey of a 1000 mods lol

[Kyleyadon]

It's kinda sad, that I can set my timing by ear better than my mechanic did with the "proper" tools. Wasted a tank and a half of gas because the timing was too far advanced and the idle speed was set too high to compensate for it. Would have realized that was the problem right away, but I had faith that my mechanic did his job right and discounted that possibility. I'm still interested in swapping the auto for a stick shift, but I think that for the money, my next move will be to install a capacitive discharge multiple spark unit. I'm looking at either the 6AL or the street fire from MSD.

[War_Wagon]

I can't remember what year GM switched from points style distributors to HEI's, but if your car still has points, swap in an HEI distributor. Any truck wrecking yard will have one, as the 250 was in a million pick ups. Do that before you put a 6AL in it, it will make a big difference. Also, consider putting in a partial grill block sort of filler piece in underneath the "grill" in front of your windshield, where the wipers are. I think that was still there in '74. You need some airflow through it to feed the heater, but you don't need all of it. Pull your carpets out and take out all the insulation under them, there is probably 20 or 30 pounds worth of it in that car. Oh, and a chin spoiler under the front bumper, you can make one out pf plexiglass, those cars never had anything like that. Just my .02.

[Kyleyadon]

I hadn't thought of blocking the grill that's in front of the windshield before, so that's something else I'll look into. I still have yet to make it out to harry's u pull it, so that's one more item for me to look into getting from them.

[Frank Lee]

There's no factory blocking piece for that HVAC inlet. I doubt much air is flowing through it anyway when the blower and controls are off... so I'd leave it. Or, try taping or blocking it somehow and see what happens; at any rate it won't show up on the gaslog.

[Kyleyadon]

The grill block was causing the engine to overheat so I removed it will have to re-design and try again. I'm thinking that since I'll have to pull the engine apart to do the cam swap I want to swap the crankshaft as well, something with a longer stroke to increase displacement, and shave the head for more compression. Also an upgrade to newer lighter pistons. Any thoughts on if this would be beneficial or not?

[saand]

kylaeyadon, looks like your doing a lot of interesting and fun mods.
I have been modding my auto mazda 626 so you might be able to find some useful "easy" and cheap mods if you look at what i have done to my car (bugler). I have listed all my mods under the car garage so you should be able to see them.

The mechanical changes you are proposing sound like a very big job so i wish you good luck there and i look forward to seeing how you go.

I do wonder if the lighter pistons will do anything for you. From theory it seems they will just reduce engine inertia which i think would cause an incredibly small impact on FE if any.

Also increasing displacement will increase your fuel usage not decrease. A larger displacement will cause more air to be sucked in and out of the engine causing higher losses in efficiency. If anything you will want shorter stroke pistons which will mean you will have to change the height of the piston rods, the crankshaft and the position of the crankshaft or grind down the engine block. When i looked into this myself i decided it was too difficult and expensive.

so as for my not too informed opinion i would suggest these mods would not be beneficial but i am happy to be proven wrong

[Frank Lee]

GM did make a 153 CID straight 4 for their Chevy IIs from '62 to '70; then after that the 151 CID "Iron Duke" (available from '77 on in the Ventura and other things http://en.wikipedia.org/wiki/Chevrolet_Chevy_II_/_Nova ) ... find one and it should pretty much bolt in, I'd think.

[Kyleyadon]

I don't think I'd want to drop the engine size like that, if increasing displacement would increase fuel consumption I won't do that, but I still think increasing the compression would be worth looking into. I will do further research into the lighter pistons before making a decision and will post what I find. I do have to say though, the straight six is a kinda odd engine that I'm having trouble finding information and parts for so it's getting tempting to swap in a small v-8 just for the convenience. But I did find that the same engine was in the gmc jimmy and several other full size pick up trucks, so maybe if I do research on them I'll find the information that I'm not finding by researching the passenger cars.

[Kyleyadon]

Well, I've been doing my research, and not only I have I found information that leads me to believe that the lightweight engine components I want will benefit my FE, but I have also decided on some more mods I want to do, namely the addition of a supercharger. Here are some links to the info I've been studying.

How Does a Supercharger Get Better Fuel Mileage? | eHow.com

https://www.kmjent.com/cart/product....1&cat=0&page=2

What are the benefits of lightweight internals? - E46Fanatics

JE pistons in a nord - benefits of lightweight pistons? - Alfa Romeo Bulletin Board & Forums

Piston Fundamentals - Mustang & Fords Magazine

I also finally found a source for a good majority of the parts I want, summit racing.

GM inline 6-cylinder - 4.1L/250 - CHEVROLET - SummitRacing.com

So, now the biggest thing holding me back? MONEY

The actual mechanical work of doing the mods, won't really be a problem I'm very mechanically handy and there are no computer chips to worry about.

[Frank Lee]

I looked at all the links. Some are good, some are not, but the bottom line is you are not racing and you will not benefit from any of that.

I myself made a mistake many years ago by buying forged pistons for a 283 build. As a mild street engine, it totally didn't need them and in fact the cast pistons would have been the superior choice not just because of cost, but because of their better temperature stability. That was an expensive lesson. Live and learn.