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Congratulations!! They are awesome fun cars.

Remind us what the pulley ratio is currently for this one
 

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You could likely pick up a stock lower pulley/balancer pretty cheap and just leave the 2.38 up top.

There again, if it has the Griptec hub already, the top would be the easiest swap (by far)
 

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You could likely pick up a stock lower pulley/balancer pretty cheap and just leave the 2.38 up top.

There again, if it has the Griptec hub already, the top would be the easiest swap (by far)
Yeah, most here have the OE lower sitting in a box next to the OE injectors, HX, lifters, PR's, lid, cam, clutch pack, etc.
 

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Discussion Starter · #46 ·
Congratulations!! They are awesome fun cars.

Remind us what the pulley ratio is currently for this one
2.38 upper Grip tech, 9.45 lower.

What's the next logical step 'down' if I wanted to preserve the blower? Also the car has an Aeroforce gauge and I've been watching the IATs. IAT1 is usually well under ambient temps but IAT2 is all over the place anywhere from 155-250. Is this because of air in the system, a bad sensor, or something else? The previous owner did have a coolant flush done recently before I purchased the car.

A more extensive parts list of the car is as follows-



(2.38/9.45), ZL1 lid,

FBO,
Engine-
Frankenstein heads
Btr PDS Stage 3 cam.
Manley Pushrods
CHE Trunion upgrade.
High volume oil pump

Blower-
Milled ZL1 lid
Reinforced brick
Grip tech 2.38 whole upper assembly
ATI/DSX 9.45 lower and relocation bracket

Fuel
ID 1080S
DSX flex fuel sensor
DSX auxillary pump

Cooling-
Vadar upper and lower heat exchanger
2 gallon BMR tank.


I'll get pics up next time I have a chance.
 

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WeaponX has a bunch of different pulley information on this link.
Congrats on the new whip
 

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Discussion Starter · #48 ·

WeaponX has a bunch of different pulley information on this link.
Congrats on the new whip
Thanks! Ive seen that ratio table before but unfortunately I dont see my exact combination on there. I can infer though from my setup that its way on the extreme end and I want to dial it way back. I'm also very concerned about this IAT2 temp issue with it showing what I'm assuming are nonsensically high numbers. Hoping its just a bad sensor.
 

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Your pully ratio is 9.45 divided by 2.38 = 3.97
3.97 * your redline RPM is blower speed. So, at 6000 engine rpm that would be 23,823 blower rpm. At 6500rpm 25,805 blower rpm.

Shoot for 22,000-ish blower RPM or lower.

Here is a chart that might help
 

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As a side note, the aggressive pulley isn't going to explode the blower or anything, particularly if you keep the engine RPMs down. The blower bearing become a maintenance item when you spin it fast. It's also not as efficient, but a lot of people do it.

For the IAT2 that is as high as you say, it's likely either an air pocket in the heat exchangers or a bad sensor. I don't know if the Vaders have a port on top that allows you to bleed. I would make sure there they are fully bled.
 

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Discussion Starter · #51 ·
Would the car pull timing based off of a bad IAT2 reading? I'll check Vadders site to see if they have a bleed system.
 

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Yes. Above 160 typically but the tune can change that.
 

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Discussion Starter · #53 ·
The idle video wont upload but heres some pics of the car. I cant find anything on Vadder's site about having a way to bleed air out of the system and from the videos Ive watched it looks like a pain in the ass to get air out.
 

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Discussion Starter · #54 ·
So it looks like the largest Griptech pulley I can get is a 2.55 which would put me at 3.70. Are there any other concerns with a change other than just getting the car tuned again with the swap?

Also another silly question, can replacing an IAT2 sensor introduce air into system any kind of way? Is there a good telltale sign to know if it's a bad sensor or air leading to nonsensically high IAT2s?
 

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Just a belt and the tune is just a good idea anyway

The IAT2 doesn't measure the water. It measures the air temp post blower. So it wouldn't introduce air into the water if changed it.

It's hard to trouble shoot over the internet but the first things I would check:

Air bubble in heat exchanger. Without a place to bleed at the actual heat exchanger it's a pita to get all the air out. I don't have a good idea here. You'll just have to fight with it until satisfied.

The pump: make sure the hx pump is working and flowing strong. If it's stock a pierburg might be a good upgrade.

Also recommend posting the question as it's own thread in the appropriate sub forum so more people see it.

Nice car BTW!
 

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You can run the pump with a OBD II scanner and burp it overnight. Wash rinse and repeat. Very easy and people have trouble doing it. I got the air out of mine in a day.
 

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You could put a 2.5 upper on it to tame it down a little... Idk if I would go with a stock pulley with the rest of the mods. How do you expect to be driving it? Obviously the blower isn't going to see life threatening speed until you get up in the rev range.
 

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Discussion Starter · #58 ·
I don't know if this would help in my situation or not but the car does have an ice tank and I seem to recall reading somewhere here that those can somehow be effective in getting air out of the system? Again thanks for all the info guys. I've got weeks of reading to do to get informed about the car.
 
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