Braking in, just some questions

[Tapi]

After this cold winter I got my GN Opel on the road again yesterday. I installed a fuel pressure gauge, boost gauge and a multimeter for O2-signal.

For some reason, I didn't get the thing cool enough with thermostat (new one) so I took it off. Does that do any harm?

Fuel pressure was about 2,3 bar (33 psi) when running. Is it too low?

The O2-sensor signal was about 0,55 - 0,80 V most of the time. A bit too rich mixture but safe?

The car didn't roll well. Sometimes it just wouldn't move when idling at D. When the boost got up to 0,55 bar (8 psi) at #3, the noise got up but barely any difference was at speed. How could I say if my tranny needs some efforts?

I have connected a GN wiring harness to a Chevy TH200R4 and I made a manually operating lock-up-switch. It grounds the violet wire. It didn't seem to have any effects when I switched it on and off while driving. How do I know, which pin at the tranny is for this purpose?

 

[blackbuick87]

Put the thermostat back in. Otherwise the coolant will not stay in the block long enough to act as a heat exchanger. You have a bad radiator or its plugged.

 

[Whooshmobile]

How hot does the engine get? If everything is working correctly, you should be able to keep the engine temperature below 180 degrees (Farenheit) with a low temperature thermostat installed on a normal day, with normal driving. If the engine runs hotter than that, you should try to find the real problem such as radiator, low coolant, etc. You need a thermostat, otherwise, the engine will not heat up enough for the computer to go into "closed loop mode".

I try to tune for O2's around 780 mv at WOT (wide open throttle).

Does the engine run poor when you try to go, or does it run well, but is held back by something?

 

[Tapi]

With thermostat the gauge pointed 200-220 F and wihout it ~180 F. The radiator is a big aluminum one but I don't know about air flowing through it. In front of the radiator there's also intercooler and tarnsmission oil cooler, which causes some of the heat.

The engine seems to run well. When I try to push the car without engine running, it's too hard for myself. I need a buddy to help me on that. Is that kind of "non-rolling" common for automatic tranny?

 

[Whooshmobile]

There probably isn't alot of air flowing through the radiator given the shape of the Opel. Also, a front mount intercooler makes cooling even worse. Just make sure your radiator and cooling lines are clean. How old is the radiator? Maybe it needs cleaned. If you think that might be the problem, you can take it out and bring it to a radiator shop to be cleaned.

If you don't have a fan pulling air through the radiator, that would be a good thing to install. You can measure the radiator and purchase an electric fan that fits. The best way to wire it would be to buy a temperature switch that turns the fan on and off at preset temperatures.

For the thermostat, it sounds like you might just have too hot of thermostat. You can purchase a 160 degree thermostat. That is what most of the guys here use. These engines run best when kept cool.

For the rolling problem, it sounds like you might have a brake hanging up. I know it is simple, but did you check your emergency brake? If you suspect the transmission, an easy test would be to unbolt the driveshaft and try to roll the car.

Does it make any strange noises?

 

[Tapi]

Radiator is clean. It's new.

I have a 1200 cfm blowing fan (pretty strong thing..) sucking air through the intercooler and radiator. It's wired so that it wont turn off when engine cools down.

I'll check that thermostat, I don't know what it's rated.

No, the handbrake isn't the thing slowing me. I remember that this hard rolling started, when I first time installed the driveshaft. Now I have different rear end, so that won't be a problem.

This thing sounds as a bus (tranny is keeping some noise) without boost. That noise isn't just so bad.

I don't have a kick-down cable attached, so I usually won't get 0,5 bar boost until at #3 gear. Then the car sounds as a helicopter but the moving isn't as impressive.

 

[Whooshmobile]

I dont' see any obvious problems with your cooling system. Try a 160 degree thermostat and let us know what happens. Hopefully you can at least keep it around 180 degrees while driving normally on a normal day.

So the trans. whines, like a bus? Does it make noise while in park and through all of the gears?

If so, it sounds like your torque converter or pump, maybe. Try posting a detailed description of your problem in the Transmission Tech section of this board. It is moderated by WE4 (Bruce), who is a very knowledgable and helpfull guy.

I would get the TV cable hooked up as soon as possible because it controls the trans. and tells it what to do as far as pressures. Your car won't act right unless it is installed and adjusted properly. At what RPM is it shifting right now?

For reference, without powerbraking, my car reaches full boost (adjusted to ~17psi while on pump gas) by 3000 rpm and holds it through all of the gears while shifting at 5000 rpm.

Also, your Chevy 200-4R trans. should work fine as far as drivability, but unless strengthened, won't last very long if the car runs well. 86-87 "BRF" transmissions have stronger parts and are the prefered 200-4R transmission.

Did you install the GN engine in the car? Did you make a twin turbo setup for it? I only ask because all GN's only have 1 turbo stock. Is the engine fairly stock? I would be interested in seeing some pictures if you have some.

 

[Chuck Leeper]

KIckdown cable??

There is no kickdown cable on a 200-4R. If you are referring to the TV cable and it's not there, the trans WILL FAIL in a short time. The TV circuit controls pressure to the clutches, etc. The pressure rises as the cable is pulled when you step on the accelerator. DO NOT drive the car w/out the cable.
Put the cable on, push the release button on the end at the throttle body and push the cable sheath toward the firewall til it stops. Then open the throttle to full open. The cable will click as it moves out. It will stop when you reach WOT.
As for the heating: I would look to be sure the inlet air flow is not going beside the rad and thru other openings such as the headlites, etc. You may have to add deflector plates in some areas so the air has to go thru the rad. The fans are not wired backward are they?? If they are, the air will be pushed, not pulled thru.
Another trick is to remove the hood seal at the rear of the hood. This allows hot air that's trapped in the engine bay to escape.
Also, be sure the lower rad hose is not being sucked shut. It should have a wire spring in it to prevent this.
A properly operating cooling system should hold the temp at within 5* of the stat, assuming the stat value is correct for the engine. IE: a 150* stat in an engine/system designed to operate
W/ a 180* stat won't be within the 5* range.

As for the lockup clutch. If you are at idle, trans in gear and you close the switch, the engine should die. If it does not, then the clutch is failed or the circuit is not working.

HTH,

 

[Tapi]

I looked at the old thermostat. It was rated 180 degrees. That is too much?

Trans doesn't make noise while in park or not moving. It whines a little while moving.

What is the difference between kickdown and TV-cable? How does driving without it hurt the tranny? It is shifting at about 3000 rpm with medium throttle now. If it would shift down when I floor this, I would not handle this thing.. (my car is a LOT lighter than usual GN:s)

Yes, I know the original setup in GN. I made this conversion to twinturbo myself. At my home page you can see some pictures about it. The block, pistons and shafts are stock.

This car's front end doesn't let any air through unless it goes through the radiator. There are no other holes. Fan is wired right.

I'll have to try driving without the hood, if that would make a difference.

 

[Whooshmobile]

I would try installing a new 160* thermostat. Also, you might be on the right track in removing the hood to see ift that helps cooling while driving. It is possible that your engine compartment is sealed up tight enough that when the air enters through the radiator, it has nowhere to go, and pressurizes the engine compartment. If removing the hood helps substantially (it will help let air out), you could look into making vents in the fenders or something.

For the trans- Definately install the TV cable. As stated before, it controls the pressures in your transmission. You will damage the transmission by not installing it and adjusting it right. It doesn't just tell the trans when to downshift.

The whine doesn't sound good, but I am not sure what it could be. Probably not the pump or converter, otherwise it should do it all of the time, regardless whether the car is moving or not. I would guess that the whine and the hard rolling problem are related, though.

The twin turbo setup on your home page is pretty awsome. I bet the car is pretty quick even at such low boost levels. But, we all want more power, don't we?

 

[Tapi]

One problem seems to be solved!

Today we had this "annual spring cruising" and we just cruised through the city at walking speed in a 1-2 mile long chain. This bad rolling came so bad, that I had to stop completely. After some cooling down I noticed that the brake pedal felt weird.

This is the diagnosis: Driver's side header heated braking fluid in "primary circuit", it expanded and started to brake me down. I installed a bushing between these "primary and secondary" cylinders and the problem didn't appear on a test drive!

...My braking system is not very simple...