whalepirot

Also: Power OR reliability; inverse relationship!

How do I know! Ouch.

Charsel

Reliability comes first. NA may not be as fast, but nitrous oxide, turbo/supercharging has potential of cooking/blowing up engine innerds. Not going to be a track car, yet.

aklim

Fast, cheap and reliable. The holy grail. Pick any 2.

MatthewMiller

In general I doubt a hot cam is going to cost any mpg. IIRC, isn't it basically the LT4 cam, or very similar? It has a bit more overlap than the stock LT1 cam, and so any mpg lost would be at idle and around-town driving. But it will still be little if any loss.
That said, a cam is a lot of work and expense, and honestly I'm not sure the gains from a hot cam would be worth it. I'd suggest the headers and maybe rockers, which are relatively easy bolt-ons.

Your 95 car should be a mass-airflow system, right? I doubt it will need any "tune" to accommodate those mods. It might even accommodate the hot cam without at tune. If you do need to change the PCM calibrations, the bad news is that it's hard to find someone to do it for you on a car that old. The good - really good - news is that you can do it yourself with a cheap program and adapter called Tunercat, and any one of several data-logging programs. For under $100 you can do everything yourself that you might ever need. The data-logging can also help you diagnose certain things, such as a failed O2 sensor, too. So I suggest that you get these tools, store a copy of the OE calibrations, and then start getting comfortable with the adjustments. That way, if you do ever decide to go more wild with the mods, you are ready to roll your own tune.

whalepirot

Over the decades with my C4 (and numerous mods) there were times I was about to quit and sell it due to overheating, no-starts, broken diffy and other issues. It took LOTS of time to sort out and become relatively reliable; a large part of why I leave my C5 Vert totally stock.

My Smart Cabrio taught me that the least fuel is used at lowest RPM.. duh! Hence the corporate push for low-end torque engines. Basic physics dictates that more fuel is needed for more acceleration.

C4s, stock, get pretty amazing fuel econ, better with each model year. The '02 is 40-50% better than my '84 for Hwy mpg and is a better all-around-use car, IMO, and I feel lucky to have two Vettes that serve my diametrically opposed goals. I suggest leaving your DD alone and working towards a hot play toy.

kkesler

Easiest and best thing I've done so far gave me more power and about 10% better mpg.

What did I do? I quit running gas with ethanol in it. I started running "pure gas" and they have never run better.

Mr. Peabody

Well heck you bought the right color... everything's going to be ok

If you are going to the parts expense and labor effort of installing the roller rockers I would suggest that you at least look at the GM Hot Cam kit. It comes with the RR the correct springs & retainers as well as the hot cam.

I had that done 10 years ago along with stainless works long tubes and have been very happy with the results on my 95. For the first 6 years I used it as my DD too.

aklim

That is incredible. Base stock is 114500 BTU and ethanol 10% is 111836 BTU. 2664 BTU or 2.32% difference. Where is the 7.68% coming from?

https://en.m.wikipedia.org/wiki/Gasoline_gallon_equivalent

aklim

IDK about the thing being as easy as you allude to. You can easily know how to make adjustments since you are tweaking software. That said, like any craft, it hasn't been simple to master. Give me a few hours and I can learn how to do weld. Doesn't make me a good at it. That takes years to get the experience which is why they pay experienced people more because they generally can do a job better than a greenhorn that just graduated from school.

Why? If you are racing and keep changing combinations, sure. Once you set it up and it is right why adjust anymore?

kkesler

Dunno, guess I'm just making sh*t up.

biggiefl

Not sure if you can do the 1.6's and the hot cam so pick your poison because they can cost about the same.

Cjunkie

A couple weeks ago i started running 90 octane pure gas in my 86. It seems to like it better and with a slight increase in mpg.
I have nothing scientific to gauge it against lol may be a placebo effect.

Phoenix'97

I figured out why ethanol, even at 10% blend with gasoline, is bad for your motor and fuel economy when my fuel pump quit on me one day and I had to get the car towed to a maintenance shop. There was a caked layer of gunky ethanol separation at the bottom of my gas tank, along with some water accumulation, and it was only a matter of time before it got sucked up into my fuel pump when I drove my car on too low of a fuel tank one day. I have been using ethanol free pure gasoline since 2012 and I have never had a problem since then.

Here is how Ethanol ruins your motor, fuel injectors, fuel lines, fuel pump, fuel tank, and gives you less fuel economy than pure gasoline! Unlike Butanol, Ethanol is hygroscopic, which means it draws in water moisture and bonds with it. So, with time, you will have a decent amount of water accumulation in your fuel tank, and before then, water in the fuel won't be good for mileage nor your fuel system. Ethanol, also goes through phase separation, which is why you need to buy STABIL fuel stabilizer when you are storing ethanol blended fuel for long periods of time! Ethanol will actually separate from the gasoline and settle at the bottom of your fuel tank as a gunky substance which will wreak havoc on the fuel system, and before then, ruin your fuel economy and gunk up the injectors.

Long story short, Ethanol blended gasoline is LITERALLY "watered down" gasoline and it will degrade your fuel economy! Now, I plan to go further than using pure gasoline when I find a company to purchase Iso-Butanol fuel from, a higher octane rated Butanol that can be safely used in higher compression V8 motors, and it will allow me to bump up the compression on my LT1 two notches in the future so my power production and fuel economy will receive a slight boost in tandem with all the modifications I plan to make to my LT1 that will also help me make it more fuel efficient for a daily driver while also giving me instant gratification at the traffic signal.

aklim

Hard to say. For all we know the 93 octane was partly from last summer.

aklim

IDK. Around here, unless you go to a marina, it is hard to get pure gas. Even if you do, you have no idea how fresh it is and I am talking 87 octane. 93 is even less used and I have doubts it is as fresh as their 87. Anywhere with fresh gas doesn't usually seem in my area. That said, my tanks are always empty. I almost never fill up before the needle sits on empty for a bit. Whatever it could have sucked up, it would have sucked up. How did you ascertain it was that and not that the pump just plain died?

Butanol is pretty much fantasy fuel like racing gas. Hard to come by at the pump so I doubt we can compare them. I can't say I have seen one at any pump I have been at. Maybe a racetrack. Last time I pulled the pump, I didn't see anything there. If you leave the car for ages, maybe condensate but if the car runs often enough, I am not sure water is that much of a problem even if it does form and gets sucked up. Leave it outside for 10 years, sure.

Yes but by how much? And how much will pure gas cost for that extra bit of economy? I get gas at say Costco where I can for 35 cents cheaper than other E10 stations. Sure, it has 10% ethanol but how much more will I spend to get that probably stale pure gas? If I had to drive 20 miles out of the way and inconvenience myself and pay more, will I save anything with respect to gassing up on the way?

Charsel

Thanks for the info. I'll look into Tunercat. It does have MAF. Going to add cam in 5 yrs. (retire) when I don't have to worry about MPG.

Phoenix'97

It is very hard to find any gas stations offering non-ethanol blend gasoline. Ethanol blended gasoline is incentivized so gas stations make more of a profit from it as opposed to selling better pure gasoline. This website helped me to locate stations in my state that offer non-ethanol blended gasoline. I lucked out with one location at Delta Sonic and another location not too far away at a Sunoco gas station.

https://www.pure-gas.org/

I am paying 30 cents per gallon more than the price of regular ethanol blended gasoline and I am paying five cents more than 93 octane ethanol blended gasoline. Honestly, for the peace-of-mind I get after experiencing my fuel pump fiasco, I am more than willing to spend that extra couple of cents per gallon.

The shop told me and they showed me. Now, there is also the possibility that maybe I purchased bad gas.

It is possible I pumped phase-separated gunky crap gasoline into my tank if it somehow got stirred up from a recent tanker fill up, but this just addresses another problem about buying ethanol blended gasoline, any stale crap at the bottom of the tanks at any gasoline station can do some serious damage to your car! However, time plays a crucial role as well! My car was already ten years old when I bought it in 2007 and this incident happened five years after owning her. I spent the first three years storing her during the winter when I could afford it, and I did prep her with STABIL during her storage, but that doesn't mean it was fool-proof. Despite driving her every day and not allowing the fuel in my tank to sit, and fueling up with supposedly "fresh" fuel, it is still possible that a layer of stagnant fuel will remain and that fuel is what will go bad at the very bottom of your fuel tank, plus the addition of moisture accumulation from the phase-separation process. With enough time, and an inaccurate fuel gauge with stagnant ethanol-blended gasoline, you are probably filling up with less and less "fresh" fuel and it is only a matter of time before your fuel pump sucks up bad gas that has accumulated in the tank...

With regards to lower octane Bio-Butanol and higher octane Iso-Butanol, these are not fantasy fuels! The problem lies with the Ethanol subsidies. Butanol won't make it's way on to the market if attempts are not made to have it replace Ethanol in blended gasoline, and after this entire post, you should understand why! Butanol is the polar opposite of Ethanol when it comes to mixing and bonding with water, so it is right off the bat a superior fuel additive but it can also be used as a stand-alone fuel replacement for gasoline, which is why I aim to acquire it for my own personal use in the future. With a rated 102 octane, Iso-Butanol will allow me to have my LT1's compression increased by two points and this cleaner burning fuel will now help me achieve better fuel economy in that it helps keep the motor clean with extremely-minimal to no carbon deposit build-up and with the higher compression. If my modifications are done right, I could experience 2014 LT1 fuel economy, out of a second-generation iron-block LT1!

Cjunkie

Hartford Muni AP
J Stop Citgo
Both have 91 Octane pure gas in your area

kkesler

Give it another couple of tanks at least, takes a while for the ethanol hangover to end

Tom400CFI

Say.....WHAT!?