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Discussion Starter · #1 ·
Exterior of the 71 GT -done
Interior of the 71GT -done
Rims and Tires- done
exhaust -done
fuel delivery system and Weber carb-done
Suspension and shocks-done
Engine is next
Problem I have a 69 Kadette 1.9L in the GT. Warmed up I can rev up to red line in neutral with no problem. Acceleration fair 1st thru 3rd. But when I hit 4th gear at about 50-60 mph, I can run it up to about 75- 80 mph and then it bottoms out on acceleration at about 3500-3800 rpm. Almost feels like the brakes are on but I know their not. I seldom ever run the higher rpm's but I know something isn't right. I know it isn't the Weber carb or settings. My hope is that it is in the distributor advance. Old style distibutor with double advance. Could anyone point me in a direction to start looking? :cool:
 

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if you rev it and it hits a brick wall its fuel

when your rev it like in 4th gear and its like creeping up to 80mph its Air


sounds like your Air filter is clogged or to restrictive.


JMTCW

Davegt27
 

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Discussion Starter · #3 · (Edited)
davegt27 said:
if you rev it and it hits a brick wall its fuel

when your rev it like in 4th gear and its like creeping up to 80mph its Air

sounds like your Air filter is clogged or to restrictive.

JMTCW

Davegt27
Checked that possibility out already. Running a JAM air head on the Weber with a 2 and 1/2 inch cold air intake and Kand N air filter. Take it off and run it without a filter- same results :cool:
 

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If the ignition timing is too far advanced it will flatten right out too. It'll rev in the lower gears but in the upper gears where you are fighting the wind and you need power it will just get lazy and not rev.

I saw a 12 hp drop on a racing engine with just 3 degrees too much timing. It would rev to 9500 with correct timing and would NOT rev past 7800 with too much advance. Something to look for anyway....
 

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Check the distributor advance. Check out your fuel pump and fuel lines, make sure the float isn't stuck in the carb. Then check out the ignition system, make sure that the points are good and set, or the electronic ignition if so equiped is still functioning.
 

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1.9 Rpm

your running a ram-air intake ??.
If you've got a scoop and ramming the air into your carb, you'll see exactly what you're experiencing...the faster you go, the higher your intake manifold pressure gets and your starting to lean out your engine because the carb was designed to have the engine suck air and fuel through the venturi... now that isn't happening. Now you need a way to increase the flow of fuel in proportion to the increase in manifold pressure. Fuel Injection would be your best bet.
But now you need to also advance the timing further because now you have positive manifold pressure. :(
 

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Discussion Starter · #8 ·
Crusher said:
your running a ram-air intake ??.
:(
Running a JAM air head- look in the new products review section- replaces the rectangular Weber air filter. Been some discusion on the proper placement for it and I have mine mounted as high as possible for the smoothest flow :cool:
 

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Opeler
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1.9 rpm

OK, I see....Well, in neutral you can rev up because your not pushing tha car down thr road, you don't need to put puch on your gas pedal to get the rpm's up...I would agree with one of the other threads, it must be either starving for fuel, air, or maybe that engine is lacking the HP...I cant remember if you said if it was a new engine or not.
 

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ok i see thats like the K&N adapter here is what the reviewer said


Registered: Mon Nov 18, 2002
Location: Dripping Springs, TX (close to Austin)
Posts: 504 Review Date: Wed Jan 7, 2004 Recommend? no | Price paid: $60.00 | Rating: 4

Pros: Allows for ducting to front for cold air. Looks cool, matches the valve cover, aluminum dissipates heat well, so do fins. Good quality.
Cons: Too restrictive of the air flow IMHO


I am changing my original input of this item. The design is too restrictive on air flow. I had Jam Engineering make a 3/4" spacer to raise it up(Another $20) some which helped a little but still restrictive. I have used a die grinder to open up the mouth as much as possible, still restrictive. On a stock engine it may work.
All it has is looks in my opinion. I am going to look at doing something different and write off the money wasted as research. A stock unit with K&N will flow better than this.

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George Born to Drive www.geocities.com/opelenvy 73 GT, 1.9, 32/36 DGEV, Sprint, Cold air intake, Jacobs, Pertronix, etc... '75 Sportwagon Automatic
 

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Here is a pic of the Jam Engineering remote aircleaner adapter that I modified by cutting the original snout off and welding on a 3-inch aluminum tube I made from rolled sheet aluminum. I also used part of the Jam Engineering 99004.351: Solex/Weber aircleaner adapter to raise the remote aircleaner adapter up level with the carb top plate. It now seems to work as well if not better than the square K&N filter sitting on top of the carb. I don't know if it flows better than the filter on the carb but the engine is not sucking in hot air.

Here is a link to a higher quality picture then the attached image.

http://www.imagestation.com/picture/sraid159/p1f5cbd8cf9198d2c050e3e61f9a31c01/f4fa3479.jpg

hth
Brian
 

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Discussion Starter · #12 ·
Wondering if my gas pedel placement might be PART of the problem- seems to be setting kinda low to the floor. Could anyone tell me how to raise the gas pedel higher from the floor? :cool:
 

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(Wondering if my gas pedel placement might be PART of the problem- seems to be setting kinda low to the floor. Could anyone tell me how to raise the gas pedel higher from the floor? )



Ya, try lifting your foot. :D
 

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There is an adjustment mechanism in the engine bay. Unsecure the placement mechanism(a slide-in pressure clamp). Slide out adjustable rod from its hole. Screw adjustment to desired floor location.
 

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Before you try to adjust the gas pedal check to see if the throttle plates are all the way open. With the car off have someone press the gas pedal all the way to the floor and look down inside the carburetor. You may have to open up the choke plates (top ones) to see the throttle plates (bottom ones). They should be straight up and down. If they are your pedal is fine. If not an adjustment is necessary to get the throttle plates all the way open with the pedal at the floor or just above it.

hth
Brian
 

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My brother and I both had the condition mentioned above. Both of our Opels' carb linkage came from the factory adjusted such that the secondaries were only opening 1/3 upon full throttle.

We took different approaches to checking for this condition. I checked mine with the engine shut off.
 

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Discussion Starter · #17 · (Edited)
bq97 said:
Before you try to adjust the gas pedal check to see if the throttle plates are all the way open. With the car off have someone press the gas pedal all the way to the floor and look down inside the carburetor. You may have to open up the choke plates (top ones) to see the throttle plates (bottom ones). They should be straight up and down. If they are your pedal is fine. If not an adjustment is necessary to get the throttle plates all the way open with the pedal at the floor or just above it.

hth
Brian
Wife put the gas pedal to the floor- said she felt honored to sit in the drivers seat for the first time in 4 years. With the pedal all the way down and looking past the choke plate, the throttle plate on the passenger side opens all the way and gas is injected down the throat but nothing happened on the driver side throttle plate. Looks like they are partially open but they didn't move. Houston- do I have a problem here? :cool:
 

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yes sir i believe that surely could be it! :D

now all ya gotta do is adjust it. you can see where the gas pedal comes through the firewall, and where the throttle linkage fits into it, and secured with a small clip. remove the clip, and spin the small "pin" downward to make a longer distance between where the gas pedal is attatching to the linkage, and the ball end of the linkage. if you havent see the gas pedal setup, you surely wont know what i'm talking about cuz i dont have real good names for these things, but i hope that a meager attempt with no specific names can help ya tom!
 

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Discussion Starter · #19 ·
greensmurf20 said:
yes sir i believe that surely could be it! :D

now all ya gotta do is adjust it. you can see where the gas pedal comes through the firewall, and where the throttle linkage fits into it, and secured with a small clip. remove the clip, and spin the small "pin" downward to make a longer distance between where the gas pedal is attatching to the linkage, and the ball end of the linkage.
Think I got it figured out. I will lenghten the distance tommorow after work. Will this longer length make both throttles open when floored?? :cool:
 

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adjusting this paticular part of the throttle linkages will make your gas pedal raise higher off the floor. so if you have to push it further to get it to the floor, it'll open up the butterflies further. just adjust it so when its floored the butterlfies are just completely open so you arent stressing the carb when you floor the engine with excessive force on the linkages and such.
 
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