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surferjoe
Ok, so my 76, 2.0L is kind of boring now. It moves a little but still cant keep up with my buddies 1910cc Bug with Dual Carbs. I dont want to go the whole V8 route on it, just add some more torque and get it a little snappier. Any idea's on what I can do with the existing motor? I really dont want to change the fuel injection. Perhaps exhaust? Ideally I would be willing to throw another $2-3k into it.

Signed,

Need More Speed! ar15.gif
TravisNeff
backdate the exhaust for sure, other than that not much without spending all your dough with little or return. You could do the higher compression P/C's but the "while your in there's will gobble up your cash quickly (and plus if it is running right, why bother for the litte gain).

You could do a lightened flywheel and it will accelerate a little quicker. Maybe doing something to carve off some weight. I remember someone taking the big bumpers and replacing the steel reinforcments with aluminum for a substantial weight savings.

Last option is screw HP and hotrod your suspension...
lapuwali
QUOTE (Travis Neff @ Feb 18 2005, 03:54 PM)
backdate the exhaust for sure, other than that not much without spending all your dough with little or return. You could do the higher compression P/C's but the "while your in there's will gobble up your cash quickly (and plus if it is running right, why bother for the litte gain).

You could do a lightened flywheel and it will accelerate a little quicker. Maybe doing something to carve off some weight. I remember someone taking the big bumpers and replacing the steel reinforcments with aluminum for a substantial weight savings.

Last option is screw HP and hotrod your suspension...

No, DON'T backdate the exhaust! A '76 has to have all of the stock smog stuff. There isn't going to be much you can do with a '76 914 in California to get more power w/o spending a substantial amount of money and time. Just "changing the injection" won't get you much, and changing the exhaust opens you to failing the smog tests.

However, if you want more SPEED, the one thing to do on the '76 is lose weight. There's a good bit to lose on the big rubber bumper cars, and you'll still be able to pass smog.
chunger
Sounds like the cheapest alternative it diet time. . .

Get a heat gun and a scraper and pull out 30 lbs. of tar sound mats on the floors. Early bumpers, FG decklids.
MecGen

Yo surferjoe
That factory fuel injection will hold you way back when it come to HP. Not much to gain with it, still is way cool OK but you won't touch a hopped bug.
You know I have done some chip tunning before, maybe I should look for a junked 914 ecm and maybe play with it HHMmmmmm, converting the ignition points to a hall effct might be a programming nitemare.
I am sure you will get many responses, but if you want my opinion, keep what you got, or get ready for carbs,
Have fun
WBR
Joe



party.gif
lapuwali
QUOTE (JoeSpark @ Feb 18 2005, 04:04 PM)
Yo surferjoe
That factory fuel injection will hold you way back when it come to HP. Not much to gain with it, still is way cool OK but you won't touch a hopped bug.
You know I have done some chip tunning before, maybe I should look for a junked 914 ecm and maybe play with it HHMmmmmm, converting the ignition points to a hall effct might be a programming nitemare.
I am sure you will get many responses, but if you want my opinion, keep what you got, or get ready for carbs,
Have fun
WBR
Joe



party.gif

The 914 ECU is all analog. It cannot be "chipped". There's no software to alter.

If you want to simply ignore smog requirements, then exhaust, porting, and a cam are required to really get any more power. You could swap in an aftermarket ECU to gain tunability. As long as you're not worrying about smog, you can do a lot better than the earlier exhaust to gain power, as well.

All of this really only matters if your goal is to beat your friend's Bug in a drag race. If he's losing you in the twisties, spend your $3000 on a good high-performance driving school, tires, and suspension. That will make a much bigger difference than anything you'd do to the engine.
Reiche
As a CA '76, all you can do will have to be within smog-legal parameters. You are significantly constrained by the exhaust system. The best you can do is optimize and tweak slightly.

Take care of the basics first. Make sure all your FI grounds and connectors are clean. Also make sure the wiring harness is good. The signals the sensors send the ECU are based on resistance. If there is extra resistance in the circuits, the ECU will adjust accordingly, but not usually to your advantage.
If you want to tweak the FI, read up on D-jet. There isn't a whole lot that can be done, but there are a few things.
If the engine is tired, a good rebuild will restore a bit of lost power. While it's apart, you could try bumping the compression a bit. A more modern catalytic converter might help a bit too.
Rand
Please help unconfuse me, because I'm getting different opinions about desmogging my 75...

First of all, I am smog exempt in WA, so I don't care about passing any tests.

I was concerned about the can of worms I would open by removing the cat to open up the exhaust and let it breath easier and cooler. But I've heard it's no problem, and plugging off the stuff on the intake side is a piece of cake and wouldn't affect the running quality.

Please elaborate on the pros/cons of desmogging a 75/76.

TheCabinetmaker
Rand, the big pro is the increase in horsepower. The smog pump, air injection tubes, cat, and heat xchangers all rob power and obstruct engine breathing. The only con I can think of is it won't be completely original, and that ain't a con to me.
Mueller
QUOTE
Please elaborate on the pros/cons of desmogging a 75/76

it's easy, but can be costly*, the earlier exhausts that have no cat. are better as you've told, the air injectors can be plugged up and the smog pump and pulley easily come off...about the only "cons" are that it'll cost some money and time

don't expect too much HP gain, about a 5hp difference between the 75/76 setup...

*worse case would be stripping an exhaust stud in the head


as for the original poster....swapping engines only takes a few hours, you could always have a warmed up engine and your smog motor.....if you do go the second motor route, I'd stay away from carbs and try to keep the motor sorta stock looking, if you get pulled over for something they can do a search and see if you have hot-rodded your car if the cop was that determined...

Dominic
Tear all that smog shit off and install a Header !
If you live in Cali, just keep the original parts to put on every 2 years for your smog check.

If you don't have to smog your car, take the restrictive exhaust system off and throw it away. Put on a set of early (73'-74') 2.0L or SSI 2.0L heat exchangers & muffler or just install a header, it's the most bang for your $$$.

Disconnect the smog pump and plug the smog injectors so they don't leak any exhaust.

beerchug.gif
jim912928
if you have 2-3k....turbo it!
anthony
It's also a lot of work to do every two years. Best to the sell the car and buy a 914-6 with a big six or a 911 if you crave power. Anything you do will cost $$$.

If you want to go faster, learn how to drive faster by autocrossing and getting some track time.
Dave_Darling
To the original poster--for something near $1500, get a [url="http://www.tangerineracing.com/Super_Header.htm#SUPER HEADER COMPLETE SYSTEM PRICES"]Tangerine Racing Super Header[/url] for a "stock" motor. Swap your stock exhaust back onto the car every other year when you get your smog test.

If you have a smog pump, the belt should "accidentally" come off one day. But make sure to spin the pump (by hand or put the belt back on) about once a month to make sure it doesn't freeze up.

The header is probably the biggest amount of power you'll get out of the car.

You can get a bit more power if you take the heads off and have them shaved a bit to bump the compression up. About 8.5:1 should be doable, even with CA's excuse for "premium"-grade fuel. Costs for this will vary, depending on what else needs to be done to the heads and how much of the work you're doing yourself.

You can probably even swap in 96mm P&Cs for 2056cc displacement without throwing off the D-jet very much. You will probably still be able to pass smog just fine... Umm, probably...

Sadly, just about any power-adding modification you make will make it at least a little more difficult to pass smog.

--DD
ArtechnikA
if you don't like your car, you should sell it and buy one you do like.

there will -always- be cars faster than yours.
Randal
QUOTE
If you want to go faster, learn how to drive faster by autocrossing and getting some track time.


Good advice.

Randy,

If you really want to figure out where to spend money, first spend a year autoxing or time trialing in your "stock" car.

After that you'll know what you want to do and in which class, which of course determines the modifications you'll be able to make and stay in class.

Otherwise, just like the rest of us, you'll spend money, get limited results and when you finally figure out what you really want to do, rebuild it all again.

Your $2K is better spent at 1 day $30 autox's or two day $250 time trials learning how to blow the doors off your buddy with the VW.
lapuwali
QUOTE (RandyLok @ Feb 18 2005, 04:31 PM)
Please help unconfuse me, because I'm getting different opinions about desmogging my 75...

First of all, I am smog exempt in WA, so I don't care about passing any tests.

I was concerned about the can of worms I would open by removing the cat to open up the exhaust and let it breath easier and cooler. But I've heard it's no problem, and plugging off the stuff on the intake side is a piece of cake and wouldn't affect the running quality.

Please elaborate on the pros/cons of desmogging a 75/76.

If you have no smog tests to worry about, there are no real cons. The early emissions systems were so ineffective that you'd probably not even pollute any more without it than you do with it. In California, there's a "visual" test that ensures that you have the stuff on the car, even if it doesn't actually work.

If you do remove the air pump and ever intend to use it again, store it carefully in a completely sealed bag. These things can't be obtained new anymore, and buying one used that actually works is pretty difficult.
Jake Raby
http://www.aircooledtechnology.com/store/p...&cat=308&page=1

There ya go....

3010 bucks and some change..

Its good for 120 Ponies with a pair of dual carbs-tested and dyno proven...
tesserra
I agree with Randal. I had a tired 76 with the smog and I used to get some pretty good times autoxing.
I think the best, easyest thing you could do is get a "test pipe" that goes in place of the cat. This will give you a better top end and will preserve that oh so expensive catalitic converter for when you really need it, every other year. Other than that get a pre 75 car and go nuts.
Your car is too clean and original to modify.
It has a lot of value in being original.

George
Rand
My desmog intentions are more concerned with engine longevity than power, since I've heard the smog crap makes the 75/76 cars run hotter and shortens the lifespan a bit. Picking up a couple ponies is a nice bonus.

I've seen horror stories on newer cars that had more complex systems, where an ignorant owner tried to clean up the junk and never could get it running quite right again. If all have to do is remove the smog pump & plug the holes, and replace the cat with a piece of exhaust pipe, and the car only runs better... my concerns are alleviated.

The 75 is smog exempt here in WA. I think my autocrossing days are over (love it, but wife doesn't *sigh*). It's not going to cost me anything (a piece of exhaust pipe and a little time... unless I'm missing something). Makes sense to me to go for it.

Thanks for the input gang.
xsboost90
my car is exempt here finally, after 25yrs. I swapped the motor from the smogger to a pre smog 2.0 w/a cam, stainless heatexchanger headers and lightened flywheel. We'll see what itll do w/ an electronic ignition.
rhodyguy
randy, if you don't have the coinage for a complete heat exhanger swap contact dan root, he's local. he has/had a nice muffler with a bypass pipe for your year.

k
opera guy
QUOTE (lapuwali @ Feb 18 2005, 04:15 PM)

The 914 ECU is all analog. It cannot be "chipped". There's no software to alter.

i have eeprom programers idea.gif is that what you mean by "analog"?
Andyrew
The computer case has no chips. it is in a gell type cell... There is no way to change with without buying a new computer system.

Ie you would have to go with a stand alone computer like the Megasquirt.

If you want some more, Get a KNN air filter and some headers and remove the smog belt. But keep in mind everything you do To it you have to take off and put back on.

lapuwali
QUOTE (opera guy @ Feb 19 2005, 12:48 PM)
QUOTE (lapuwali @ Feb 18 2005, 04:15 PM)

The 914 ECU is all analog.  It cannot be "chipped".  There's no software to alter.

i have eeprom programers idea.gif is that what you mean by "analog"?

No EPROM inside. No EEPROM. No ROM of any kind.

Unlike a digital ECU, which has a microprocessor inside running a program (which resides in memory somewhere, like in an EPROM) to control things, the D-Jet (and early L-Jet) ECUs are all analog discrete transistors, resistors, diodes, etc. There's no microprocessor, no program. A square(ish) waveform comes in from the trigger points, gets altered by the inductance coils in the MPS and temperature sensors, and goes straight on to the injector drivers as a square(ish) waveform.

Some values can be changed by swapping out resistors or capacitors of different values, but not everything can be altered this way. Some things would require significant rewiring of the board. The "program" that the ECU "runs" is essentially in the layout and values of the components. Once can substantially change the fuel curve in the ECU, but doing so would require doing a lot of reverse engineering with an oscilloscope. Brad Ander's web site has the most relevant data on this.
redshift
QUOTE (ArtechnikA @ Feb 18 2005, 09:01 PM)
there will -always- be cars faster than yours.

Oh yeeeeee of little faith....

wavey.gif


M
airsix
QUOTE (jim912928 @ Feb 18 2005, 04:48 PM)
if you have 2-3k....turbo it!

...and have enough left over for a paint job! (I did digital injection/ignition + turbo for $675*)

-Ben M.


*PerfectPower ECU $500 installed + $50 junkyard turbo + $125 plumbing & misc.
MecGen
Hi
Thanx for the info Lapuwali, I see what you mean, much easier to build/buy a system.
Hey Operaguy, what you doin whith that machine, work or hobby ? HHhhmmmmmm....
WBR
Joe


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Bleyseng
My 76 2.0L car went the 96mm pistons, 8.5to1 comp., heads ported and larger exhaust valves 38mm, backdated to 73 SSI HE's with a Bursch, tuned the Djet on a dyno.
The best dyno runs were 95 Rear wheel hp which is about 110-115hp. Car was pretty quick. I like the Djet as its very simple and can be tuned if you are careful.
Its now coming apart for a major upgrade to a 2.4/4.

Geoff
porsha916
First, check compression, if it's good,electronic point replacement, K&N air filter,replace & index plugs, loose the big bumpers, low profile tires(messes up speedo) Try it, then if not enough power sell it or buy another car (smog exempt). good luck (new to posting).
scotty914
dump the smog car get a smog exempt and suby it for 2500 bucks you get 175 hp, or even better get a svx 3.3 or wrx for about 240 hp or so, and it even looks kinda stock
DJsRepS
I own a grand ole 72 1.7 live in fla no smog laws. I bought a cool looking header exaust with a short muffler system and could feel the difference and it even sounded better. Im not sure if it helped but I put one of those cone filters on it as well. Better than the oil bath.
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