100+ MPG CRX HF VREX - help needed!

[mcc6]

When you say "skirt spoilers", do you mean like a body kit that goes all around, or do you only mean side skirts? I was considering putting side skirts only on my VX, but don't know if that hurts or helps aerodynamics. I've always heard that the full body kit helps...but don't know about just the side skirts.

[theholycow]

I'm not aware of any manual transmission that has a pump, but I'm certainly no expert.

You could possibly add cooling fins to the transmission pan and/or housing...but if your manual transmission is making that much heat then you've got a problem that's wasting a lot of energy and is going to destroy your FE. That heat has to come from somewhere. I guess if your engine is running as hot as you plan then the transmission could end up with a lot of the engine's waste heat instead of making more of its own.

[pgfpro]

Originally Posted by 101mpg

But the car IS going to be manual. This vehicle will run HOT so I want all the cooling I can get. Oil cooler FOR CERTAIN. When I do my cross-country trip I'll hit a lot of mountains - and with an HF-based transmission and big mountains I'll need additional cooling.

On the engine with running a taller gear set it would be a good idea to run a engine oil cooler. I to live in a mountainous area and have ran an oil cooler with a engine oil temp gauge. You can see the oil temps increase a lot when you climb a major grade. Plus if you run a belly pan it would also help keep the oil cool from the lack of air movement. You could also control the oil temps by running some type of shield in front of the cooler during the winter months.

[101mpg]

Definitely thinking of running a belly pan. This is going to be a complete build - strip the car down to the frame, likely re-strip it and have it powder coated, and build from scratch. New wiring, rerouted and made shorter, brand-new brake lines throughout, etc.

Engine oil cooler for certain.

I do need a good source for cooling the transmission with a belly pan. By the way everyone feel free to throw in their two cents about the fluids used in every part of the vehicle - they will all be brand new of course, and plan on Amsoil where I can, anything else I can pick up that will be top of the line for fuel economy and vehicle life will go in.

I'd love something like the Mugen CRX Pro kit which is nearly cost prohibitive, not sure what gives the best fuel economy but I'm planning on spoilers all the way around the vehicle not just side skirts. New front bumper and rear bumper spoilers as well as the sides. Wings West maybe? Other ideas?

The problem with this is that I may have to do some really expensive A/B/A testing with multiple kits. I know the Mugen kit (not the knock-offs) actually bolts on where several other types are put on with tape and not made as well. Most spoiler kits are made for racing not FE, unfortunately.

[101mpg]

I'm specifically looking for donations for the VREX, by the way. I have yet to locate a proper frame. Looking for the early 1988 HF with pillar-mounted seatbelts, little to zero rust. I know, hard to find.

I can use pretty much anything - VX wheels, tires, spare bulbs, spare tools, an extra racing seat you might have unused in your garage, spare carpeting, any parts off a VX, a SuperMid you may not be using, any VX or CRX engine parts, a Civic Wagovan manual transmission, any CRX (especially HF) drivetrain parts, any CRX Si suspension parts, brake lines, rear disc brakes from the CRX or Civic series (Integra brakes aren't bad either), a spare carbon fiber hood, spoiler kits, clutch parts, racing pedals, or anything else you can think of that I might be able to use, especially if you think I haven't thought of it.

I'm located in West Virginia, and can travel to pick up most items if you're east of the Mississippi in general. If you've got a working VX or CRX I might be able to travel further to drive it back.

I've been in negotiations with my mechanic as to what this all will cost, how long it will take to do the heart & lung transplant, best time of year for him to start it off, etc.

I am grateful for all the community help I can get. My stated goal is to put together a 100+ MPG vehicle out of mostly stock parts. The only things I think I'm going to have to actually have custom made are a couple of the gears for the transmission, and that's not TOO custom IMO.

Thank you all for your help and input.

[101mpg]

Here is what I plan on doing for the transmission:

Civic Wagovan MANUAL transmission. It will be geared as a 6-speed (5-speed plus granny gear gives me 6 speeds). Final drive from the HF. Basically most gears from the HF, although I think first gear is from the Si. 6th gear is .55:1, which may mean 5th and 6th may have to be custom gears. The goal is 90-95% stock parts out of different vehicles - I'll keep a tally when I'm done of what is not a stock part you can just buy anywhere, for the entire vehicle. Basically use existing technology.

I hope this answers people's questions on the transmission. I'll be having a transmission expert do the tranny rebuild, and fill it with the appropriate Amsoil fluid. The clutch will be all brand-new and I'd like to get the best recommendations I can on it.

[GasSavers_Erik]

What size tires will you be using? What speed do you plan on driving cross country?

If you are using 175/70 R13 (890 revs per mile). The HF 2.95 final drive + a .55 high gear will give only 1444 rpm at 60 mph.

This is good in terms of reducing friction losses but... does anyone know if there is a low rpm threshold on the VX lean burn? If so, I suppose you could always just downshift until you can use lean burn- but this would negate the purpose of the extra weight of the 6 speed 4WD tranny.

You may want to also check that the wagon tranny will fit in the CRX (there may need to be a hole cut in the firewall to make room for the rear wheel drive yoke on the back of this tranny).

[pgfpro]

I have a mpguino for OBD1 I could donate that I never used.

This would work great if you switch over to OBD1 with a OBD0 to OBD1 harness and a few other mods to complete the conversion.

Add some CROME engine management to the mix and you would have a killer setup. You could go with an Moates Ostrich or I could burn you a chip with built in lean burn as a base map. I might even be able to come up with a extra OBD1 ecu.

The Ostrich would work better for fine tuning that you could do on the fly with RTP. I could even work with you on teaching the program and some basic EFI theory.

I have done this in the past and now have over a 100 different people tuning there own cars.

But I would like to get a star next to my name if this all goes down.

[101mpg]

I appreciate the donation offer pgf - and this is going to be a community project as much as I can make it. We can get you a star next to your name. =)

Erik - plan on doing freeway speeds - not over 70 and will figure out exact speeds with lots of prior testing.

Tires will be close to stock. I have thought about but not specifically planned out the low revs with lean burn - I will keep it in the forefront once I get to computer programming. PGF makes some good points - I will have to get some custom mapping which I don't know what to do, but when I get there will make sure I get everyone's help.

I appreciate the offer to learn EFI theory.

I know there is a low threshold on the lean burn but will have to work on getting it mapped. May even need to only engage lean burn in a couple of gears?

Wagovan tranny is SUPPOSED to fit but will have the mechanic work that out once I get that far. That's the nice thing about these threads - can go back and revisit each issue as it comes up!

I appreciate the thoughts on these matters - they are not trivial.

[pgfpro]

Here's a fuel map of my Del Sol when it was turbocharged.

The numbers in the cells are raw numbers with Neptune and Crome management. As you can see this is a speed density system.
Inches HG on the left side and psi on the right with zero being between
0.5"hg and 0.4psi.

Most speed density systems use the map sensor to determine load (in this case left/right columns. Then they use up/down or rows for rpm.

So from the map above you can see that at 15"hg and 2625rpm you have a raw number of 153. This number will convert to a pulse width and that will be how long the injector is told to stay open for one engine cycle in
milliseconds or m/s.

As you can see on the far left there are very low numbers 26"hg. This are close to what the factory runs for decel injector off to conserve fuel.

Also whats nice about this is if your in a lower gear your swept area will not be the same as a high gear so you can just set a few rows for your 5th gear for lean burn. As you can see by the highlighted cells.

The timing table looks just like this but with rpm and timing values.