Laser temp readers for A/F reading cyl by cyl? - Moparts Forums

Register Log In Moparts Forums Unlawfl's Race & Engine Tech Laser temp readers for A/F reading cyl by cyl?

Print Thread

Laser temp readers for A/F reading cyl by cyl? #604729 02/05/10 10:27 AM 02/05/10 10:27 AM
Joined: Jan 2003 Posts: 4,573 ...gently down the stream LAR_414 OP master
LAR_414 OP master Joined: Jan 2003 Posts: 4,573 ...gently down the stream	Anybody ever use one of those hand held laser temperature tools to read each tube on headers to see if the air fuel mix is off between cylinders. Maybe a way to try out different damns and such on an intake manifold to get a more evened out temp reading from tube to tube. Harbor Freight has a pretty inexpensive one for like $30 on sale right now. I was thinking then you could just hold the motor at a certain rpm to heat the headers up and then take some temp readings to see how the fuel is being drawn between cylinders.

Re: Laser temp readers for A/F reading cyl by cyl? [Re: LAR_414] #604730 02/05/10 11:05 AM 02/05/10 11:05 AM
Joined: Dec 2007 Posts: 10,542 BROOK PARK, OH WILD BILL Senior Member of the Junior Dragster Club
WILD BILL Senior Member of the Junior Dragster Club Joined: Dec 2007 Posts: 10,542 BROOK PARK, OH	I've ever only used it to find a dead hole. Not sure how accurate it would be.

Re: Laser temp readers for A/F reading cyl by cyl? [Re: WILD BILL] #604731 02/05/10 11:54 AM 02/05/10 11:54 AM
Joined: Jan 2003 Posts: 1,633 Jacksonville, NC RonP top fuel
RonP top fuel Joined: Jan 2003 Posts: 1,633 Jacksonville, NC	I don't think it is very accurate especially if the headers are coated or there is a variance in thickness of the flange or header tubing at all. I tried it on my coated headers and I can get a 100+ degree temp swing just by moving the laser a couple inches on the tube or flange. Better probably as Bill stated for a dead cyl. just my

Re: Laser temp readers for A/F reading cyl by cyl? [Re: RonP] #604732 02/05/10 12:05 PM 02/05/10 12:05 PM
Joined: Jan 2003 Posts: 1,329 NC DCM71cuda pro stock
DCM71cuda pro stock Joined: Jan 2003 Posts: 1,329 NC	One thing people don't always realize with IR temperature readers. You actually read a much larger area than just the 'dot'. The cheaper ones will have something like a 6:1 or 8:1 ratio. Meaning that if you are six inches away from your target, you are actually measuring the average temp in a 1" cirlce, not just on the red dot.

Re: Laser temp readers for A/F reading cyl by cyl? [Re: DCM71cuda] #604733 02/05/10 12:11 PM 02/05/10 12:11 PM
Joined: Jan 2003 Posts: 4,243 Canada Kam*Kuda master
Kam*Kuda master Joined: Jan 2003 Posts: 4,243 Canada	Quote: One thing people don't always realize with IR temperature readers. You actually read a much larger area than just the 'dot'. The cheaper ones will have something like a 6:1 or 8:1 ratio. Meaning that if you are six inches away from your target, you are actually measuring the average temp in a 1" cirlce, not just on the red dot. I did not know that 1970 Barracuda Convertible 1968 Satellite Street Strip car 1654.5 Mustang 1955 Land Rover

Re: Laser temp readers for A/F reading cyl by cyl? [Re: DCM71cuda] #604734 02/05/10 12:16 PM 02/05/10 12:16 PM
Joined: Jan 2003 Posts: 1,633 Jacksonville, NC RonP top fuel
RonP top fuel Joined: Jan 2003 Posts: 1,633 Jacksonville, NC	Quote: One thing people don't always realize with IR temperature readers. You actually read a much larger area than just the 'dot'. The cheaper ones will have something like a 6:1 or 8:1 ratio. Meaning that if you are six inches away from your target, you are actually measuring the average temp in a 1" cirlce, not just on the red dot. good point. I think mine is 1/2 area or less. I need to look now that I think about it as it was an expensive one. With that, I still get the variance because that header coating isn't the same thickness when it is sprayed either.

Re: Laser temp readers for A/F reading cyl by cyl? [Re: RonP] #604735 02/05/10 12:32 PM 02/05/10 12:32 PM
Joined: Jan 2003 Posts: 4,573 ...gently down the stream LAR_414 OP master
LAR_414 OP master Joined: Jan 2003 Posts: 4,573 ...gently down the stream	I'm just wondering if it's worth it to try and get somewhat close. I've never tried it, so I have zero experience on this. What kind of temps or temp range do you usually see? Maybe it's good if you see one or two cylinders that are running 100's of degrees hotter than others, meaning they are lean. I've got my LM-1 and it's reading each side of the exahust. So I'm seeing an average of 4 cylinders. Sure would be nice to tune this cross ram a little better if I know one or two cylinders are really getting robbed, by the others.

Re: Laser temp readers for A/F reading cyl by cyl? [Re: LAR_414] #604736 02/05/10 12:57 PM 02/05/10 12:57 PM
Joined: Jan 2007 Posts: 3,695 nc E emarine01 master
emarine01 master E Joined: Jan 2007 Posts: 3,695 nc	I have been takin IR readings from just after the build, if ya fool with it enough you will see patterns in your tune

Re: Laser temp readers for A/F reading cyl by cyl? [Re: emarine01] #604737 02/05/10 02:00 PM 02/05/10 02:00 PM
Joined: Oct 2007 Posts: 3,871 Oregon hooziewhatsit master
hooziewhatsit master Joined: Oct 2007 Posts: 3,871 Oregon	you also need to look at the max temp the gun will read. My cheapo one doesn't go over 450*F. Good for finding a dead hole, but not much else. If you ever find yourself in a fair fight, your tactics suck.

Re: Laser temp readers for A/F reading cyl by cyl? [Re: LAR_414] #604738 02/05/10 02:44 PM 02/05/10 02:44 PM
Joined: Jan 2003 Posts: 30,989 Oregon A AndyF I Win
AndyF I Win A Joined: Jan 2003 Posts: 30,989 Oregon	It works fine, I use a temp gun all the time for tuning and dyno work. Point it at the oil pan, radiator, block, headers, intake, valve covers, etc. The key is to have the right kind of finish on the parts. Flat black is the best finish for measuring temps. Chrome or anything shiny is the worst.

Re: Laser temp readers for A/F reading cyl by cyl? [Re: AndyF] #604739 02/05/10 04:06 PM 02/05/10 04:06 PM
Joined: Dec 2006 Posts: 4,647 aotearoa rebel master
rebel master Joined: Dec 2006 Posts: 4,647 aotearoa	andy's right about the finish. i have a very expensive IR t/meter but on my headers it reads nothing like the pyro's. it's better for reading slick temps & oil pans as previously suggested.

Re: Laser temp readers for A/F reading cyl by cyl? [Re: LAR_414] #604740 02/05/10 05:21 PM 02/05/10 05:21 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	To many variables to use a IC to measure the A/F ratio with any where near accurate readings... a few thousandths thicker coating on the header will give you 30* different reading, add in the center cylinder tend to run hotter.... just use a A/F meter or invest in EGTs, I have both but now days use the EGTs (on all 8 cyl exactly 1" from the head surface) to set the flow on the intakes I make and the A/F for its job

Re: Laser temp readers for A/F reading cyl by cyl? [Re: MR_P_BODY] #604741 02/05/10 07:53 PM 02/05/10 07:53 PM
Joined: Jan 2003 Posts: 4,152 SO. CAL. 7 70blackfish master
70blackfish master 7 Joined: Jan 2003 Posts: 4,152 SO. CAL.	Say a cylinder or two are lean or rich, how would you fix that?

Re: Laser temp readers for A/F reading cyl by cyl? [Re: 70blackfish] #604742 02/05/10 07:59 PM 02/05/10 07:59 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Quote: Say a cylinder or two are lean or rich, how would you fix that? Either try jetting that corner up or work on those ports on the intake

Moderated by Al_Alguire, Hotwheelsjr, moparts, not_a_charger, RangerDan440, tboomer

Hop To

Powered by UBB.threads™ PHP Forum Software 7.7.1