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boostedhfrex 07-04-2008 02:28 PM

Running too rich at part throttle and warm up
 
1 Attachment(s)
When I start my car for the first 2 1-2 minutes it runs rich (12.2-12.4 afr) and won't really accept any throttle. Once the car warms up, the afr's go down to 14.8 and I'm happy with that for now. Now the other issue is that riding down the road from about 2800-4000rpm at part throttle the car runs incrediblly rich. Basically anywhere from 15hg's and below down to 21ish hg with a 10.8-11.2 afr. I've spent alot of time trying to lean out these part throttle areas and the car really doesnt respond to any of the changes until it sipmly pegs lean and then you have a delay in throttle response at tip in. Its basically too rich or too lean. I've tuned a couple cars for myself and other people and have never ran into this problem at all. I'm attaching a copy of the tune

Here's the setup
D16Z6
vitaras/tt rods
mild ported head w/zex 59300 cam
cdm 57trim turbo
660cc injectors
2.5 dp/straight exhaust

boostedhfrex 07-04-2008 02:29 PM

Re: Running too rich at part throttle and warm up
 
And thhe car is running on crome btw

Tom-Guy 07-04-2008 03:05 PM

Re: Running too rich at part throttle and warm up
 
A lot of the 660cc injectors I see are overbored stock Honda injectors. If that's what you have then I'm happy to tell you that your problem is you can't reliably modify Honda injectors past 550cc; this is what Venoms are, and why they suck.

The last set of 660cc I saw would actualy toggle too rich to too lean at idle and at super light throttle like you flipped a switch, and as soon as you tuned to get things so they were stoich it would flip back the other direction. WOTs were fine, though, but the plugs were "foggy" due to shitty/poor atomisation.

Running 12:1 AFR when cold is normal, minimises fuel fall out in the manifold while the mani is cold. Your lack of ability to drive it for a second, however, is something else. ??

boostedhfrex 07-04-2008 03:11 PM

Re: Running too rich at part throttle and warm up
 
These injectors are the skinny black deka siemens injectors. I've never dealt with these before, have you. I think the throttle problem when the car is cold might be due to the fact that I had played with the idle screw the other day and its not 100% in phase witht he iacv.

Tom-Guy 07-04-2008 03:37 PM

Re: Running too rich at part throttle and warm up
 
No, I've never dealt with them.

I'd start over with my basemap. Get the car warmed up, with a virgin map do the generic recurve on your injectors, and then under the advanced tab of your fuel modifiers start adding offset until you idle at stoich.

Sometimes if the voltage @ idle varies a half volt or so when you rev up a couple hundred rpms it won't work correctly, but in theory if everything is correct your whole part throttle map should be witin 1/2 AFR of target. It doesn't always work that way if mechanical timing is off (decked, milled, aftermarket cam gears not accurately labelled) or if you've done a cam change or the IM/turbo mani/header is real different from stock.

Some of the larger guns go from super lean to rich as you add injector pulse, and then they lean back out as you add more. I've never dealt with those injectors, and I've never seen it in anything as small as a 660cc, but sometimes tuning is trying wacky things as a trial and error sort of thing.

Get play with it and get more info, if you still have problems I'll see if I can't be more help.

boostedhfrex 07-04-2008 03:53 PM

Re: Running too rich at part throttle and warm up
 

Originally Posted by Joseph Davis

I'd start over with my basemap. Get the car warmed up, with a virgin map do the generic recurve on your injectors, and then under the advanced tab of your fuel modifiers start adding offset until you idle at stoich.

Sometimes if the voltage @ idle varies a half volt or so when you rev up a couple hundred rpms it won't work correctly, but in theory if everything is correct your whole part throttle map should be witin 1/2 AFR of target. It doesn't always work that way if mechanical timing is off (decked, milled, aftermarket cam gears not accurately labelled) or if you've done a cam change or the IM/turbo mani/header is real different from stock.

So take a stock p28 map, recalculate for 660cc injectors...then paste your values in?

I do have a milled head and a bigger cam so could timing be an issue.

Tom-Guy 07-04-2008 03:56 PM

Re: Running too rich at part throttle and warm up
 
I'd be careful about my eCtune timing maps into Crome, etc. They might work fine, but your engine might want something different.

boostedhfrex 07-04-2008 04:06 PM

Re: Running too rich at part throttle and warm up
 

Originally Posted by Joseph Davis
I'd be careful about my eCtune timing maps into Crome, etc. They might work fine, but your engine might want something different.

Do you have any crome maps??

Tom-Guy 07-04-2008 04:12 PM

Re: Running too rich at part throttle and warm up
 
I tune more turbo ITRs than I have tuned D16, oddly enough. So, ah, aside from some D16Y8 maps, no.

Set your timing ~12 degrees at 10 psi, your car may like more along the lines of 13-15 which are common figures Matt Shue's come up with in the past.


boostedhfrex 07-04-2008 04:24 PM

Re: Running too rich at part throttle and warm up
 

Originally Posted by Joseph Davis
then under the advanced tab of your fuel modifiers start adding offset until you idle at stoich.

could the idea of these values being off have something to do with my rich throttle tip in??

Thanks again JD, I guess I'm learnin like the noob in ur sig


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