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-   -   85 turbo still 0-60 18 seconds at best... (http://www.peachparts.com/shopforum/showthread.php?t=196450)

ichbineinekrous 08-07-2007 05:02 PM

85 turbo still 0-60 18 seconds at best...
 
19 to 19.5 is more the norm. In the past 3 months this is what Ive done:

valves adjusted, transmission shifts crisply and smoothly (once warmed up), diesel purge, ALDA removed then replaced (no difference) lines and overboost solenoid cleaned, wastegate spring adjusted to enable turbo to top out at 14 psi. (per new boost gauge), Fuel filters replaced, tank strainer replaced, cooling system flushed...maybe a couple other things that I can't remember also.

I'm not obsessed with achieving 13 sec. 0-60, I just want Gretchen to run at a respectable 14-15 secs. I now have a compression tester, and after reading the ip timing procedure I'm don't feel overly confident that I can address that myself. Any other ideas out there folks?

tjohn 08-07-2007 05:09 PM

The quickest and easiest thing that you haven't mentioned is adjusting the linkages. You want to be certain that pushing the go pedal down to just above the kickdown switch result in the ip giving maximum fueling. This frequently can cause a problem. Also need a clean air filter.

Assuming you've already knocked off those, does the tranny shift at the maximum shift points on the speedometer? If the tranny down shifts too fast you'll have a hard time achieving proper 0-60 speeds.

After that, I think you probably are looking at something more involved, like IP timing.

Brian Carlton 08-07-2007 05:15 PM

Quote:

Originally Posted by ichbineinekrous (Post 1585465)
and after reading the ip timing procedure I'm don't feel overly confident that I can address that myself. Any other ideas out there folks?

With the '85, you can use the RIV lights to do injection timing. Much faster and more accurate than the procedure that you were reading.

Also, it's time to check the chain for elongation and see if the camshaft is late.

ichbineinekrous 08-07-2007 05:32 PM

yes to linkage adjustment, primarily had to take the slack out of the rod that travels down to the ip, the little cam/ stopper wasn't even making contact with the stop with linkage at full spread. Did air filter also, I'll check the mph at each shift tonight, I think its close to what it should be.

Last time I did the valves, I got inconsistent results checking the tc stretch. from 0 deg. to 5 deg. I did not use a dial gauge on the valve spring method which is poss. more accurate. I just rotated the engine till number 1 was at TDC and read the scale on the pulley. Did this 5 times, (and it was really fun bloodyin' up my knuckles on the back of the radiator) and got 5 different answers. I'll do a search on IRV lights as I'm not familiar. Thanks guys.

ForcedInduction 08-07-2007 08:59 PM

Ditto on the linkage. You can have a helper or heavy object press the accelerator to the floor and make sure the arm on the IP is touching it's stop bolt. Also make sure the rubber joint on the firewall is not cracking when the accelerator is pressed.

Zoonhollis 08-07-2007 10:25 PM

You mention replacing the ALDA, but did you actually adjust it to correspond to the newly-added boost? Shoving more air into the intake alone won't do it; it needs more fuel.

ForcedInduction 08-07-2007 10:56 PM

Adjusting the ALDA after adjusting the boost is not necessary.

lietuviai 08-07-2007 11:48 PM

Quote:

Originally Posted by ichbineinekrous (Post 1585498)
(and it was really fun bloodyin' up my knuckles on the back of the radiator)

Save your knuckles and use the pulley nut of the power steering pump to turn your engine. That's the way I've always done it. If your belts are tight enough, this method works great.

Zoonhollis 08-07-2007 11:54 PM

Quote:

Originally Posted by ForcedInduction (Post 1585836)
Adjusting the ALDA after adjusting the boost is not necessary.

It most certainly is. Boost means nothing if there's not a concomitant increase in fuel delivered. I learned this both by doing it myself, and from Herr Dieseling Doktor (to say nothing of basic chemistry/physics). Do a search if you don't believe me, or look here:

http://www.peachparts.com/Wikka/OM617BoostControl

If the originator of this thread has not done this adjustment, no wonder his car is still sluggish.

ichbineinekrous 08-08-2007 09:24 AM

The progression of events was...

1. Sheared ALDA adjustment rod off attempting to enrich
2. Removed now useless ALDA
3. Installed boost gauge, turbo making 9 psi
4. Adjusted wastegate, turbo now produces 13-ish
5. Got freaked out about overboost, bought usd ALDA and installed
6. Made no adjustment, protective metal shroud is virgin

I plan to remove the intake manifold pressure sensor, after reading a post here about it getting completely crudded up, and to check the overboost protection solenoid. I'll prob. clean it out again, or at least T the boost gauge in between the ALDA and overboost solenoid to check the amount getting to the ALDA.

winmutt 08-08-2007 09:45 AM

Quote:

Originally Posted by ichbineinekrous (Post 1586104)
The progression of events was...

1. Sheared ALDA adjustment rod off attempting to enrich
2. Removed now useless ALDA
3. Installed boost gauge, turbo making 9 psi
4. Adjusted wastegate, turbo now produces 13-ish
5. Got freaked out about overboost, bought usd ALDA and installed
6. Made no adjustment, protective metal shroud is virgin

I plan to remove the intake manifold pressure sensor, after reading a post here about it getting completely crudded up, and to check the overboost protection solenoid. I'll prob. clean it out again, or at least T the boost gauge in between the ALDA and overboost solenoid to check the amount getting to the ALDA.

How are your injectors? Have you disabled your EGR and ARV yet?

BigBadJohn 08-08-2007 09:52 AM

Those stock turbos never were the best were they?

Zoonhollis 08-08-2007 10:00 AM

I can definitely understand if you're a little gun-shy about adjusting the new ALDA, but I still maintain that this must be done in order to take advantage of your increased boost. I would begin with 1/8 to 1/4 turns CCW.

winmutt 08-08-2007 10:03 AM

Quote:

Originally Posted by Zoonhollis (Post 1586137)
I can definitely understand if you're a little gun-shy about adjusting the new ALDA, but I still maintain that this must be done in order to take advantage of your increased boost. I would begin with 1/8 to 1/4 turns CCW.

Uh no it does not have to be adjust for increased boost. Not at all. It probably SHOULD be adjust since it is new to that engine and probably not much of an adjustment.

TheDon 08-08-2007 10:35 AM

Quote:

Originally Posted by Zoonhollis (Post 1585910)
It most certainly is. Boost means nothing if there's not a concomitant increase in fuel delivered. I learned this both by doing it myself, and from Herr Dieseling Doktor (to say nothing of basic chemistry/physics). Do a search if you don't believe me, or look here:

http://www.peachparts.com/Wikka/OM617BoostControl

If the originator of this thread has not done this adjustment, no wonder his car is still sluggish.

just letting you know.. Lance(FI).. knows his stuff


You could remove the ALDA and see how that works for you


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