First 1/4 mile run with new engine

[silver]

At what IAT2 temp does it start to pull timing? I was thinking it was above 140F, but I couldn't find it in the search. The highest I've seen is about 125F and it comes back down to 105F. The heat exchangers were around 90F. I haven't made a bunch of hard runs in a row though.

130 from memory.

you and I are running the same heat exchanger now, mine's mounted in front of the radiator and yours up top, so it would be pretty interesting to compare during a run.

On track (not drag strip) I would see IAT's go upwards of 170-180 but they would cool back down in the turns maybe to 150 or so.

Now, I haven't gotten it to go above 130, and it cools down quickly from there.

IAT's can't really be compared with what's your temp vs mine but more of what's the delta between IAT1 and IAT2...if you got your car nice and hot after 20 minutes of spirited driving...then drove at highway speeds, what would the difference be between 1 and 2...if it's 30 or under you're doing great....if it's 50 or over, something's not right........or you have a stock atom.


**what do you mean when you say " the heat exchangers were about 90F" do you mean that was ambient? or IAT1 or something else.

[RyanD]

IAT's can't really be compared with what's your temp vs mine but more of what's the delta between IAT1 and IAT2...if you got your car nice and hot after 20 minutes of spirited driving...then drove at highway speeds, what would the difference be between 1 and 2...if it's 30 or under you're doing great....if it's 50 or over, something's not right........or you have a stock atom.


**what do you mean when you say " the heat exchangers were about 90F" do you mean that was ambient? or IAT1 or something else.

I'll check again, but I think the delta was in the 20-30 degree range when everything was warmed up.

I meant after a long drive I jumped out and took the temperatures of the heat exchangers with an IR temp gun to get an idea what the water temperature was. 90F seemed ok to me.

[silver]

I'll check again, but I think the delta was in the 20-30 degree range when everything was warmed up.

I meant after a long drive I jumped out and took the temperatures of the heat exchangers with an IR temp gun to get an idea what the water temperature was. 90F seemed ok to me.

ahh I gotcha..

yeah our cars would probably have a better delta than 20 degrees if the laminova tubes did a better job getting heat into the water.

since the water's only getting to 90 degrees we're not going to take a whole lot out of that

[RyanD]

I just checked my boost with an OBDII scanner. The 3.15 pulley makes 14psi and the 2.9 pulley makes 16psi. That's based on the MAP sensor, so I need to get an analog gage to check it. I thought it should be at least 20psi.

[silver]

I just checked my boost with an OBDII scanner. The 3.15 pulley makes 14psi and the 2.9 pulley makes 16psi. That's based on the MAP sensor, so I need to get an analog gage to check it. I thought it should be at least 20psi.

I see 15-16 psi with the 3.15 pulley on the harrop

[silver]

I see 15-16 psi with the 3.15 pulley on the harrop

side note: when I changed my oil filter, the transmission cables are so tight, that they end up being pushed into that solenoid on the bottom of the supercharger, and if that solenoid can't extend fully, you don't get full boost.

I was getting 2-4lbs of boost when it could barely move, then 10-12 lbs when it could mostly move, but fully free 15-16

[RyanD]

side note: when I changed my oil filter, the transmission cables are so tight, that they end up being pushed into that solenoid on the bottom of the supercharger, and if that solenoid can't extend fully, you don't get full boost.

I was getting 2-4lbs of boost when it could barely move, then 10-12 lbs when it could mostly move, but fully free 15-16

Ok, I'll check the solenoid. Didn't know that was possible.

The Cobalt guys say they are getting more boost, but they have a factory boost gauge. I wouldn't put it past GM to calibrate the gauge to read higher than actual boost. I'm going to at least get a cheap gauge and hook it up temporarily to check mine. Is there a line I can tap into to measure boost? The solenoid line is on the inlet side, isn't it?

What PSI can I expect from "x" pulley?
64mm / 2.5" ~ 27.5 psi
70mm / 2.75" ~ 25 psi
75mm / 2.95" ~ 22.5 psi
80mm / 3.15" ~ 20 psi
85mm / 3.35" ~ 17.5 psi
89mm / 3.5" ~15psi

[silver]

Ok, I'll check the solenoid. Didn't know that was possible.

The Cobalt guys say they are getting more boost, but they have a factory boost gauge. I wouldn't put it past GM to calibrate the gauge to read higher than actual boost. I'm going to at least get a cheap gauge and hook it up temporarily to check mine. Is there a line I can tap into to measure boost? The solenoid line is on the inlet side, isn't it?

What PSI can I expect from "x" pulley?
64mm / 2.5" ~ 27.5 psi
70mm / 2.75" ~ 25 psi
75mm / 2.95" ~ 22.5 psi
80mm / 3.15" ~ 20 psi
85mm / 3.35" ~ 17.5 psi
89mm / 3.5" ~15psi

solenoid is visable if you remove the trapezoidal hatch in the rear firewall, also gives you access to move the transmission cables IF they are in the way.

coming off the solenoid is a vaccumm hose which could also be leaking causing loss of boost.

Why don't you trust the boost gauge on the aeroforce? what I've noticed is also your boost changes very quickly so it may peak at 16, but if you're watching the road, you may only see it get to 14. it definitely builds boost as the rpm's go up so your peak boost should not happen until the top of the rpm range.


I think you wrote fictitious numbers above right? just to make an example? because they seem really high, unless they are for the stock blower.

[RyanD]

Why don't you trust the boost gauge on the aeroforce? what I've noticed is also your boost changes very quickly so it may peak at 16, but if you're watching the road, you may only see it get to 14. it definitely builds boost as the rpm's go up so your peak boost should not happen until the top of the rpm range.


I think you wrote fictitious numbers above right? just to make an example? because they seem really high, unless they are for the stock blower.

I used the recording function on my OBDII scanner. I realize boost will vary a little versus RPM, but it should be fairly constant within a couple psi.

The numbers above seem to be accepted values from the Cobalt/Redline guys with Harrops on LSJs. This is the FAQ on the Redline forum, and the FAQ on the Cobalt forum has the same numbers.
FAQ: Harrop LSJ-1320 TVS & You - Saturn ION RedLine Forums

That's why I was questioning if I should be getting 20psi instead of 15psi. There is also a post on the other Atom forum that says a 3.15" pulley makes 20psi. I just want to verify that I don't have a leak, slipping belt, etc.

[silver]

I used the recording function on my OBDII scanner. I realize boost will vary a little versus RPM, but it should be fairly constant within a couple psi.

The numbers above seem to be accepted values from the Cobalt/Redline guys with Harrops on LSJs. This is the FAQ on the Redline forum, and the FAQ on the Cobalt forum has the same numbers.
FAQ: Harrop LSJ-1320 TVS & You - Saturn ION RedLine Forums

That's why I was questioning if I should be getting 20psi instead of 15psi. There is also a post on the other Atom forum that says a 3.15" pulley makes 20psi. I just want to verify that I don't have a leak, slipping belt, etc.

ahh, I would guess that their boost will be different b/c their belt set up is different than ours.....that's just my guess, I think Positron needs to weigh in, he knows all that stuff