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Discussion Starter #1
I just had my 74 GTV restored, used to have a Shankle Sure start, ran great with it, swapped it out for a rebuilt Ingram TA, pump set to spec using factory manual and factory tools. Starts ok, idle 1100, while warming up throttle to 3500 seems fluffy, like running on 3 cylinders, once warm that disappears, but no snap until around 3500, pulls smoothly below that when warm but the power is not there. Pittatore cams set at 104 lobe centers using a degree wheel. It鈥檚 been over 20 years since I drove it regularly but had great power throughout the rev spectrum, now feels like a two stroke when it hits 3500. Any thoughts?
 

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Ok. When you set the pump gap at 175F coolant temp, did you use a dummy T/A that has a 27mm extension? Or did you use the actual T/A?

A frequent problem that arises is that the 1974 model pump requires a 27mm T/A extension at 175F. BUT, the rebuilt T/As that you get now have either a 29mm or 31mm extension at 175F. Test them in a pot of heating water on the stove. I recommend you do this while the wife is out shopping. The T/A adjustment screw in the pump body may not be able to adjust enough to compensate for the longer extension.

The end result is the T/A will lean the mixture out way early resulting in poor warm-up performance.

The solution to the problem is to use one ordinary hardware store washer (if the T/A is a 29mm extension model) or two washers, if it's a 31mm extension. You will have to grind a little off two edges to clear the T/A hold-down screws. Ordinary hardware store flat washers are about 2mm thick so that will fool the injection pump into thinking that it has a 27mm extension T/A and starting/warm-up performance will be restored.
 

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Discussion Starter #6
Was set up by shop, using manual and calls to Wes Ingram, but I will pass this info along to them, the new TA did extend past 27mm, so you could be on to something, Thanks
 

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I'll need to know what the "T" number is on the injection pump dataplate. Just because it's a 1994 model, doesn't necessarily mean that the pump hasn't been swapped out with a later model.

The proper "T" number for a '74 model is T255/1. Starting in 1976 with the T260/1 pumps, 29mm T/As were used.
 

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Discussion Starter #8
I believe it's the original pump. I have owned the car since new and don't recall swapping the pump, but will check, car still not in my possession. I appreciate all your help. Thanks!
 

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In all likelihood it's a T255/1 then. Next you'd need to know if the new T/A is a 29 or 31mm extension type. I'm guessing 31mm. If you got it recently from Wes, he should know to what spec his T/A rebuilds are to.

If it's a 31mm model, put two 2mm ordinary flat washers under the lower T/A flange. You'll have to grind two edges in each washer to clear the hold-down screws. You will then have to check/reset the pump gap to .019" at 175F coolant temperature. You will find that the T/A adjustment screw will now not be bottomed-out completely.

You will probably find that your cold-start and cold-running performance will improve markedly.
 

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Discussion Starter #10
I'm pretty sure they shimmed it, but can't confirm if they adjusted the screw under the TA, or exactly what they did. Wil find out. Again, thanks for all the suggestions. Fran
 

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Did they set the relay crank (the thing the throttle cable connects to) on the intake manifold using the factory jig?? There are very few of those tools around. Most mechanics do not have one. It's real important that be set correctly. I have a loaner tool if you need it. What shop did the work?
 
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