Never seen some ones idle setup like yours is for sure. Does your atom have a wideband on it for tuning? I see at idle your timing is going negative at idle for some reason and you have a lot of stuff that needs to be changed. You can use my scan config if you like.
I don't have a wideband on the car, but I have access to a dyno with one.
Is the idle problem mostly due to the injector settings, or are there also mistakes in the timing table or somewhere else?
Injectors will screw everything if your having problems there you need those fixed first to make the rest be proper as well
Take your ls4 off and use stock until you locked it down. Ls4 causes surging issues that screw with injector settings. You can install it and adjust for it when your injectors are locked down.
@ Atom75; what dual pass endplate do you have on your car? If it's a modified stock plate you're fine, but if it is one off the special cast ZZP dual pass plate you may have a vacuum leak under the SC.
We found that our ZZP dual pass plates were cast a little higher than the stock item. This was no problem with the stock M62 blower, but if you mount a bigger Harrop SC on top it can touch the ZZP plate and the seal with manifold is not tight. We had to grind down both our ZZP plates...
(Spray f.i. with brake cleaner to test for leaks, but your idle rpm is a tad high for this...)
Last edited by Speedytec; 06-06-2014 at 04:40 AM.
Yes, I have a ZZP dual pass plate. No way to get to it on an Atom without pulling the engine.Originally Posted by Speedytec
I know, I'm driving a 850kg VX220/Speedster (Lotus Elise clone) with an LSJ in the back.
But ZZP Dual Pass plate + Harrop can be trouble. (We bought our ZZP plates some years ago) You can check if the charger touches the top side of the plate, but it's difficult to see. And see if you can spot the green bypass channel seal between the SC and the plate's air bypass channel. ( => Not good; seal should be completely hidden from view.)
Leak path was discovered by spraying brake cleaner and the resulting rise in revs.
We removed the fuel rail and the Harrop, removed the SC gasket, taped-up the intake manifold and covered everything up with a cloth. Then cardefully grinded a few mm of the top of the plate in the car.
Clean, replace stuff, job done. Perfect vacuum @ idle and no more negative timing.
Last edited by Speedytec; 06-06-2014 at 07:36 AM.
put a return fuel system on it. get rid of the ls4 tb. I have about 75 different maps for id1k's in the lsj engine setup. The ecm has a hard time controlling those injectors on the stock returnless style fuel system.
The most hated, make the most power.
93 Ranger. 5.3 D1X. 1069hp.
That requires pulling the engine again to do it correctly. Maybe I'll look at doing that next winter.
I still haven't found a good company to tune it. Any recommendations?
depends if you're willing to ship the car or not.
The most hated, make the most power.
93 Ranger. 5.3 D1X. 1069hp.
i had the same issue on hockeyman's car. the "foot" of the harrop was not seated propoerly. I had to grind it flush.
384whp/303wtq
Built 2.0LSJ: TVS w/2.6, 1000cc, Stage 2 cams, custom fuel system, E85, Dual Pass, 3"intake, 3" Catless exhaust, CIA midlength Header
I changed back to the stock throttle body and installed a new Denso O2 sensor. I had someone work on tuning it, but I'm convinced that he doesn't know what he's doing. It was undriveable after 20 tries.
I compared my file with some others, and made changes myself. Now it idles almost perfect and drives ok at low speed. Here is the tune file and log. Besides having too much fuel, does anything else look wrong?
I'm not sure about the timing tables. Am I better off to start with stock GM timing tables?
TEST1.hpt
TEST1A.hpl
Timing is always last leave it stock until you get it all sorted out
Did you check for vac leaks under the Harrop?
It looks ok to me, and now it idles steady. MAP reads 35 kPa at warm idle at 1000RPM. That would be about 65kPa vacuum on a vacuum gage. Sound about right?
Right. I was asking because the timing table in my file looks wrong.
I copied everything in the Spark tab from a stock tune file. Anything else look wrong before I try to adjust the MAF calibration?
Last edited by Atom75; 07-10-2014 at 07:26 PM.
is there o-rings around the base of the injectors? have you replaced the injector isolators with new ones? did you grease them before you put them in?
The most hated, make the most power.
93 Ranger. 5.3 D1X. 1069hp.
stupidest idea ever...injector cups pftt
2000 Ford Mustang - Top Sportsman
I see the issue with the Harrop and the ZZP dual pass plate. However, I sprayed the green seal with the engine idling and nothing happened. What symptoms were you seeing with this issue?
I also sprayed the injectors, and nothing happened either.
Harrop ZZP dual pass.jpg
I had an airleak on the aluminium/rubber SC seal, so between mani and charger, near the ZZP endplate. The green bypass seal was tight, but I found a (small) rise in idle when I sprayed on that spot.
My symtoms were a lower than commanded idle timing (sometimes negative) together with a very low ETC position. All signs the ecu was doing it's best to lower idle revs by shutting TB and retarding timing...
But 35KPa MAP reading is not bad, especially with hoter cams, (Which type?). See what it logs at normal idle speed (850-900), together with ETC position and Ign. timing.
(I heard those ID1000 injectors can be sucked into the head if not secured properly. So to prevent this you need to install an extra bigger o-ring at the injector base.)
Edit; on that pic I can spot some green color of the visible bypass seal. That indicates me your Harrop is fouling on the ZZP endplate and not sitting low enougn on the manifold with probably an airleak at the blower seal. The green bypass seal should be completely invisible from view.
And besides that you now bolted the SC down on a non-flat surface that can cause issues on the bearings...
Last edited by Speedytec; 07-16-2014 at 06:02 AM.
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