Put my older Rom back in today and it feels alot better. Just went out and ran a 0-60 .1 faster than at the track Friday night in a 2200 DA compared to the 1300 DA at the track. I'm going to let it learn all week and hopefully hit the track this weekend or next at the latest. Feels like it pulls hard again! Man I shouldn't have flashed a new Rom b4 the track, live and learn I guess!

 

Yeah you gotta let the truck learn the tune and do about 3 0-60 pulls before hitting the track

 

Any idea how many tenths it could affect it? It felt like it was holding shift and just not pulling hard on my first and only pass Today it felt really good after I put the older Rom back in. Also I think I ran it in my 87 street map, actually I'm pretty positive I did because that's what I run on the street and didn't change maps when I got there. That might be worth .1-.15 I'd say. Any idea? I feel heart broke right now thinking that headers didn't give me any gains. LOL

 

Where you running Cipher going down the track? Was the truck pulling timing on launch? There's no telling what the different tunes will effect without know how your truck is running on each tune. You gain a good bit from the truck learning the tune.

 

Timing went from 31 @ 2100 rpms to 20 @ 3425 rpms & maxed at 34 @ 5825, so yes your right it did pull timing. What causes that? Knock?

 

Too much heat (I.E. heatsoak, which is why heatsoak will kill your times) or yes knock. Low grade gas

 

During the run the outside temp was 70 and after sitting and waiting in line with the truck running my IAT was 102 degrees now that you mention it. You think the heat soak killed my times?

Now that you say that, that's like running in 100 degree heat with my IAT's like that!! Good lord, no wonder I ran the same times. This Saturday I'm going to run and give it a good cool down. This track I can basically drive right up to the line and go Thanks OFIVE!!

 

If you stall to long or at too high an rpm I'm pretty sure that can do it.

 

Yeah no doubt man, its hard sometimes to avoid heatsoak. When I was running my car, first time was right off the street, and ran horribly. Second run, I did so good, let the car sit for a while, and pushed it through the staging lanes, then I drive into the burnout area, and the car in front has something wrong. So the tech guy talked to him, finally he reversed out the way, but the car in the other got to go by itself before me. All this while I'm sitting there idleing. I was so pissed. You can feel it. I get out and run around in my car before it has had time to idle, and its a rocket. Now that's its 90+ outside, I have noticed with a passenger, my car feel no faster then my Titan in cool weather and the throttle response blows. The heat will straight up destroy your performance lol

 

When an engine pulls timing, it's going to be: engine load, intake air temperatures, or knock detection

More often than not it's the engine load and intake air temperatures. ECU's have tables that modify how much ignition is cut from intake air temperatures and they have load tables that tell the car what ignition timing to run based on load.

IF the knock sensors hear knock, they will cut ignition based on knock ignition limit tables. Basically, these tables tell the ecu how much ignition to pull in the certain areas when knock is detected.

 

So its prolly best to sit and cool after every single pass? Not to make back to back passes? Also when the timing pulls like that does it stay there or go back to normal once everything has calmed down?

 

It depends. I can hot lap my car and not lose any speed or et. But honda designed my engine to run hot and i have a very good very well insulated CAI that doesn't heatsoak.

And generally, timing will go back to normal quickly, but not all ecu's are the same. Sometimes it may stay with ignition retard for quite some time before it goes back to normal.

 

yeah it always seems when im at the track my first 3-4 passes are ALWAYS my fastest and it slowly gets worse as the night goes on....i even pop the hood and let it cool for over an hour and still run slower....GOOD LUCK DS! i was looking at those DTLTs but if you dont show much of a gain off of them im trying another brand!

 

I'll argue this till I drop...lol, but if your engine temp is at 190 (normal operating temp), you are good to go. I've hot-lapped many times with no significant ET difference as long as my engine temp was at 190.

 

I agree but hotlapping is different than heat soaked. If I hot lap my iats stay 10-15 above outside temp. Heat soak is from sitting in line with the truck running like I did. My iats were 46 degrees above outside temp at take off.

 

I'll agree that +30-40 IAT does matter for the first few seconds. Sometimes there is nothing you can do if the guys ahead of you are wasting too much time. I always wondered if a few pieces of dry ice would help if there were pockets attached to the intake air box. This would be different than icing down the intake manifold because you would leave them in there for the run.

 

Thats interesting. I wouldnt mind trying it just to see. Couldnt hurt anything right?

 

I wouldn't put them in the air box, but attached to the outside body of the box. I have no idea what kind of gas dry ice emits if it's inside the air box...

 

Yea outside of course but how?

 

I don't know, so let us know when you figure it out... Also, those flat, small, reusable plastic ice packs should work too. My first thought is duct tape...lol.

 

When i hit the track i usually get there at least an hour early so the truck can completely cool. Then i will do 2 back to back passes then take a break & let it cool for another hour. Then run a few more. I've got the best results doing it this way! I agree, heatsoak can kill your times! That's another reason i never put my fender liners back in after my header install. It lets all the hot air escape out through the front wheel's.

 

Dry ice emits CO2, carbon dioxide when it evaporates. The speed at which the air is pulled into the engine, the dry ice wouldn't cool the IAT's down enough to be worth doing imo. Now, if you could cool the entire manifold and CAI tube @ once and keep it cool, then that would make a huge difference. Icing your intake while getting your coolant temps down to 140deg. is the trick. My fastest pass was by getting my coolant temps down to 140deg and pushing it through the staging lanes (no easy feat!!). Icing the intake manifold does help. It's worth at least .05 to .1 in the 1/4.

 

Insulate everything! Coated headers, insulated intake...all of it! LOL....The intake I'm getting connects to the TB (Obviously) then runs straight forward about 6 inches and has a plate that goes down in front of the hood and catches outside air to be pulled up into the intake

Pontiac GTO "VARARAM" Cold air system *New* | eBay

 

Thats a pretty cool set up

 

O-Five, what's interesting about what you show is the fact that this sits right behind your hood scoops right? All of the concern of doing the ram air mod on our trucks with moisture getting up in there should be dismissed after looking at this design unless I'm missing something. This CAI for the GTO would be soaked in a rain storm right?

 

Well, it's actually in front of the hood scoops. It pulls air in from under the hood opening and through the front grills. There are actually plugs in the scoops from the factory, but I took those out. I'm sure water could get in there, but you would have to be driving fairly fast in the rain for it to make the path to the filter. This particular intake is known to greatly reduce heat from the intake.