tappit?

[jzwartster]

dont know I got 16+ when I had my 600 edel broc on it but had hesitation. I needed more gas flow. Now I run a 700 dual feed street avenger by Holly and run real good with great response but really drinks the fuel. Is it because its a 9:1 compression? When I bought the short block the guy said most of the guys race 'em but wont hurt to drive it either. 350+hrp with 348 lbs of foot torch.

[cgrey8]

I guess I should feel really good about getting 20-24MPG. On the daily commute, I average 22MPG, however on the highway running 55-60, I'll get upwards of 24. Interstate speeds drop it back down into the mid to upper 22s though. I'm really hoping that the 331 will get a tad better than the stock engine. Attention to details such as quench, Dynamic Compression, and running a very mild cam should help. The downside is I'm afraid I'm forcing myself into premium gas. So it better get higher MPG for the $.30/gal higher pricetag of premium.

If my area ever gets an ethanol pump, I'll be in good shape. An E30-E40 mix would put me in the same octane level as 93 octane. Although I wouldn't get the fuel economy 93 would give. Ethanol burns cleaner leaving nearly no soot in the combustion chamber or pipes.

[jzwartster]

I just like to take off fast and get up to speed. I dont spin the tires or let the RPMs up much higher than 3500. I live in town and leave it in 2nd sometimes but realy need to quit that to get a lil better milage.

[jzwartster]

The company that built the motore said a lot of the guy race these engines. he said it will be fine to run daily but will cost in the gas. I didnt get to bad of milage with my 600 edel broc on but had bad hesitation. Put my current 700 dual feed street avenger on and runs great but suck the gas. The compreddion ratio is 9:1 is that why I get so bad milage?

[cgrey8]

The Dynamic Compression Ratio tells you more than the Static Compression Ratio does. Without knowing the cam you are running, a 9:1 static could be about right or it could be very low. Although if this is a performance oriented engine, it would stand to reason that the cam probably is too in which case 9:1 is probably on the low side...but a safe compression if you are running 87 octane regular pump gas.

As for how I'm getting the fuel economy I am, that's a lot to do with the tweaks I've made in the computer. Up timing here and there, maintained the EGR, and leaned out cruise and tip-in enrichment where I can to not waste fuel. I've got the engine burning lean enough where I can wipe my finger across the inside of my exhaust pipes and all I get is brown rust and maybe a hint of black. Before I made the tweaks I did, I would get a solid black finger print due to the excessive soot created from running rich...even with fuel injection and CATs. With the stock tune, the best I could get is 20MPG and that was babying it and never WOTing it.

[carvinmark]

The company that built the motore said a lot of the guy race these engines. he said it will be fine to run daily but will cost in the gas. I didnt get to bad of milage with my 600 edel broc on but had bad hesitation. Put my current 700 dual feed street avenger on and runs great but suck the gas. The compreddion ratio is 9:1 is that why I get so bad milage?

I'd bet the accelorater pump was bad in the edelbrock carb, seen many of them bad on those carbs, I hate them and refuse to run them. Any carb with a bad or too small accelorater pump will cause a hesitation.

[jzwartster]

Im not sure what size the cam is but do know its a radical cam. She rocks sittin at a stop light at an idel. I only run non ethenal premium and usually add gas treatment or octan boost 104. There are two of our many gas station that offer this kind of fuel. Better for seal and pump in the carbs.

[cgrey8]

In that case, yeah 9:1 is on the low side. You could EASILY put a super/turbo on there and get 6-8PSI boost on there...assuming the internals can handle it. But I wouldn't be surprised if you could get upwards of 15 PSI from it. Of course that wouldn't help your fuel economy, but it would at least make use of the low compression in a meaningful way.

[jzwartster]

what do the cost? how are they installed? I have Fedural Mogal piston by Keith Black as well as main and rod bearing, Hasting rings, Ford OEM rods, Melling timing chain and Fel Pro seals and gaskets. Not sure of the heads they're 18 mill. of 68 mustang.

[cgrey8]

I don't know about cost. But here's what I can tell you...

Centrifugal superchargers are probably the easiest and cheapest to install since all they are is a device that gets a belt and forces air into the engine. They are easier to install on EFI, but there are carbed setups that can take a supercharger. Unfortunately, you often need a "blow-thru" carb in order to use a setup like this.

Positive Displacement superchargers also run off a belt, but add some height to the engine since they mount directly on top of the engine. The carb would mount directly on top of it. Again it'll use a belt. Sometimes there are clearance issues with these and the distributor. These are generally the higher output chargers, but are also the more expensive and add some complexity to clearance with the hood.

Turbochargers don't take a belt. But they do require some fancy rigging with headers. I've seen pics from people here on the forum that mounted Mustang shorty headers upside down on the engine with the collectors pointing forward and up. They mounted the turbo to those and from there, plumbed in everything else. If you have the room in the engine bay, turbos are a nice way to go. They are far less of a parasitic load on the engine so you generally get better gas mileage with turbos than you do superchargers. But if you oversize the turbos, you get "turbo-lag". I've heard of people using all sorts of turbos for their setups. I think one of the most popular are diesel turbos. Evidently, they are cheap and very reliable. But again, I wouldn't know. The downside to turbos on a Ranger is you'll need to walk into the project expecting there'll need to be custom fabbed stuff done to make it work. A person with a welder, cutting torch, and some imagination shouldn't have too much trouble doing what's needed.

Regardless of which you do, once you get above about 8 PSI, you find it beneficial or even necessary to install an intercooler which cools the boosted air. Pressurizing air has the negative side-effect of heating it. Hot air going into an engine encourages preignition. You want to avoid that as much as feasible. Without an intercooler, the best option you have is reduce the boost when the engine is detonating due to high intake temps. With an intercooler, you may find that you can make more power with less boost because the cooling of the air is actually letting more air into the engine than was getting in before with the air hot. Generally intercoolers aren't needed until you are at or above 8 PSI though. So most "budget" boosted applications stick in the 5-6 PSI range which is still a significant power boost.

Another thing to keep in mind when you boost an engine is it's 10x easier/faster to blow a head gasket or melt a piston due to too much spark advance or not enough fuel.

To make sure you are fueling enough at WOT, you'll need to invest in a Wideband O2 sensor so you can make sure your WOT fueling is staying plenty rich. Naturally aspirated WOTs should be in the 12-13 AFR range. Mildly boosted engine need to be in the 11.5-12 AFR range. Heavily boosted engines will need to be as low as 11. The added fuel is not so much for power, but for combustion temp control. Under boost, combustion temps will skyrocket. The added fuel is just there to keep that under control as much as possible. Having a Wideband sensor will let you see if you are hitting these targets or not so you know to take your foot off the gas before bad things happen. Regardless whether you are carbed or EFI, a WB O2 should be thought of as a requirement if you go boosted unless you are running a very tried-n-true configuration.

To prevent piston damage, you'll need to make sure your spark advance is retarded with boost. Straight mechanical advance distributors are not going to be your friend on a boosted application. You need a distributor with a vacuum advance so you get more timing with vacuum and less timing the deeper you go into boost. With EFI, you can setup a tune to pull spark as engine load goes up. But with carbs, you rely on the physical behavior of your components and have little way to verify what they are actually doing. So don't guess when it comes to what distributor you use. Be sure that what you are using is good for the boost levels you are trying to attain.

[jzwartster]

Wow, i think Ide just go supercharged to eliminate most of the risks, but I just bought this new carb and as you know they're not cheap. I think i do have enough room under the hood and thinking about getting a 4" cowl glass hood with the cut out, probably needed for sure. Definatly a project to think about when I am wanting a lil more. Already done everything you see in the last 6 months and got a lot to do around the house. Roof, floors, drywall, siding, it all cost money and the house is almost paid for and want everything finished in the next year when it will be paid off.

[v8ranger]

All mine fits under the hood with no problems. I am running a paxton with about 6psi of boost. I only get about 10 to 12mpg around town.. But when you have a supercharger under the hood, you always end up playing.. I love mine, it realy woke things up. I havent taken it on any trips to see wht kind of mpg it gets on the highway...

[jzwartster]

sweet! I think you have the same polished aliminum alternator as I do. I have the mounting (arm) braket on the top side and a bolt with spacer on the bottom side. I have movement in the alternator and cant come up with a senareo to stregnthen it. I almost need a braKET TO MOUNT TO THE BACK SIDE OVER TO MY INTAKE OR SOMETHING. aNY IDEAS? Sorry about the cap lock.lol. It shouldnt have any movement, when your on the gas it tight but at an idle it is not, Frustrating, we dont have any junk yards around to see if I can come up with a braket there.

[v8ranger]

If you look, you can see the brace going to the intake. What I used was the mounting brakets from a 90's 5.0 crown vic. I also had to make a spacer to keep the alt forward. I used a brake caliper slider and drilled it out for the bolt. then ground it down to fit. when I use to work at a shop I always kept odd hardware, bolt,slidders, pins, etc... I will get some pics of it today so you can see it better...

[v8ranger]

The brace that goes from the alt braket to the intake, I had to do a little modifications to it. I little cutting and re-welding so it would fit the carb intake.. You have to make sure you get the spacer in the lower mounting hole perfict.. If you dont, you end up breaking off the ear. Trust me, I did that a couple times before I finaly got it perfict... lol....