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Old 10-30-2009, 02:35 PM   #51
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Re: 350 TBI vortec heads LT4 hotcam

Quote:
Originally Posted by alvanwie View Post
I am running a similar setup to yours but with a comp cam. You said the power is just not there. On my setup that was generally an indication of not enough timing. I could not find what your timing tables look like but I attached a copy of what I am currently using. You should be careful here, mine is fairly aggressive and may not be right for your heavier truck. As for the popping on accel, that is generally a lean condition. Try adding some AE.

Attachment 187416
alvanwie,

Thanks for the timing table. Mine was not as aggressive and using yours put a whole lot of punch off the line. I got only a few knocs that I can tune out, but overall the shpae of the curve works awesome. Wonder what I should change since mine is stick?

I'm heading up to the track tonight with some drag radials! I'll let ya know what I run.
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Old 10-30-2009, 09:32 PM   #52
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Re: 350 TBI vortec heads LT4 hotcam

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Originally Posted by graebz28 View Post
alvanwie,

Thanks for the timing table. Mine was not as aggressive and using yours put a whole lot of punch off the line. I got only a few knocs that I can tune out, but overall the shpae of the curve works awesome. Wonder what I should change since mine is stick?

I'm heading up to the track tonight with some drag radials! I'll let ya know what I run.
graebz28,

Glad it helped. Are you running a similar combo? I don't think any major changes would be required for a stick, just watch for knock counts when shifting. Good luck at the track. Let us know how it goes.

Al
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Old 11-01-2009, 08:13 AM   #53
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Re: 350 TBI vortec heads LT4 hotcam

Did Some WOT tuning with the LC-1 WB O2. VE tables hit 100% up at 95 and 100 MAP so I had to increase BPC and start again.

One thing that I am concerned with is that hte WUD is showing a higher reading of the AFR of around 0.8 - 1 than the gauge that came with the LC-1. I have them both wired to the brown output wire and on the EBL it runs to the ADC channel 0. Should I also be running a ground from the EBL to the grounding location of the sensor?

Anyway, thanks again for all the help here, I still have lots to do, have not even touched AE and PE besides zeroing all the AE SA retard which helped a ton.

Also... just out of curiousity, I did my WB VE learns with 20% filter. What is a typical value people are using. I would assume 0 is ok for initial tuning, but as you get it closer you'd want to increase the filete rto 20,40, etc? thoughts?
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Old 11-01-2009, 07:47 PM   #54
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Re: 350 TBI vortec heads LT4 hotcam

Quote:
Originally Posted by 88GMC1500 View Post
Did Some WOT tuning with the LC-1 WB O2. VE tables hit 100% up at 95 and 100 MAP so I had to increase BPC and start again.

One thing that I am concerned with is that hte WUD is showing a higher reading of the AFR of around 0.8 - 1 than the gauge that came with the LC-1. I have them both wired to the brown output wire and on the EBL it runs to the ADC channel 0. Should I also be running a ground from the EBL to the grounding location of the sensor?
If you feel the gauge is correct and the EBL is off. Then create a user device in the EBL that is offset by the .8 AFR. I would check the LC-1 voltage against the gauge value to make sure that the gauge is correct.

You can also try tying the LC-1 analog ground to the EBL. It is just that doing so tends to create ground loops.


Quote:
Anyway, thanks again for all the help here, I still have lots to do, have not even touched AE and PE besides zeroing all the AE SA retard which helped a ton.
?There isn't any AE SA retard in the EBL.

Quote:
Also... just out of curiousity, I did my WB VE learns with 20% filter. What is a typical value people are using. I would assume 0 is ok for initial tuning, but as you get it closer you'd want to increase the filete rto 20,40, etc? thoughts?
The greater the filtering the higher the lag in the WB value. Use as little filtering as possible.

RBob.
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Old 11-01-2009, 08:49 PM   #55
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Re: 350 TBI vortec heads LT4 hotcam

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Originally Posted by RBob View Post
?There isn't any AE SA retard in the EBL.
My apologies, I was referring to "SA - PE Max retard" and not AE.
Quote:
Originally Posted by RBob View Post
I would check the LC-1 voltage against the gauge value to make sure that the gauge is correct.
As for which reading is accurate, I have no idea which one to trust but I like your suggestion. How exactly would you recommend performing this check since the value changes so rapidly? I'd almost need snapshots. i.e. for a given time, what is the gauge reading, EBL reading and actual voltage at the analog output.
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Old 11-01-2009, 10:48 PM   #56
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Re: 350 TBI vortec heads LT4 hotcam

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Originally Posted by 88GMC1500 View Post
My apologies, I was referring to "SA - PE Max retard" and not AE.

As for which reading is accurate, I have no idea which one to trust but I like your suggestion. How exactly would you recommend performing this check since the value changes so rapidly? I'd almost need snapshots. i.e. for a given time, what is the gauge reading, EBL reading and actual voltage at the analog output.
Hopefully the reported knock in PE mode isn't real.

In the LC-1 setup there is a sampling rate. Can slow down the output and see if the reading steady's out enough to check the voltage vs. the gauge & EBL.

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Old 11-02-2009, 12:41 AM   #57
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Re: 350 TBI vortec heads LT4 hotcam

for making my lc1 match, I do it with the motor off key on. using logworks as that will be the real a/f, then if tunerpro is displaying something different. I reprogram the outputs a few tenths of a volt to make the tunerpro match logworks. and you can do the same for your gauge by hooking it to the other output.
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Old 11-02-2009, 03:31 PM   #58
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Re: 350 TBI vortec heads LT4 hotcam

Quote:
One thing that I am concerned with is that hte WUD is showing a higher reading of the AFR of around 0.8 - 1 than the gauge that came with the LC-1. I have them both wired to the brown output wire and on the EBL it runs to the ADC channel 0. Should I also be running a ground from the EBL to the grounding location of the sensor?
That is usually a not preferred method for analog signals. You have another output (Yellow in my LC-1 manual) that you can use to connect a second input. You will have different signals unless both ebl and the gauge have equal resistance. You should trust what LogWorks is saying the value is vs either the gauge or ebl at first. Logworks was a free program that came with your LC-1. See directions to connect below.

5.3 Laptop recording of AFR or Lambda
1. If real-time recording with the Innovate LogWorks software, connect the Serial OUT connection
(unmarked) with the included 2.5mm stereo to DB-9 cable to a serial port on your laptop.
2. Connect the terminator plug (2.5mm male plug with no cable) into the Serial IN connection of
the LC-1.
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Old 11-02-2009, 03:44 PM   #59
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Re: 350 TBI vortec heads LT4 hotcam

I'll have to try logworks and the output jack with serial cable to compare, but simply defining the device to the spec of the LC-1 by hand instead of using the LC-1 preset corrected the mismatch. The LC-1 has a 7.35 - 22.39 range. The EBL had a different range pre-defined for the LC-1. Once I created a user device with the proper range, the readings sync up.

As for the yellow wire, according to the book that is the 0-1v (simulated NB) signal. The brown wire is the 0-5v (wideband). Not sure if things have changed or what, but thats what came with my kit.

On a side note, my experience tuning with WB02 has been that in the idle - 1200 range, the WB learns destroy the VE table. After 3 or 4 learns it wont even run anymore. It just surges lean to rich and you can see it in the log till the engine dies. Is this normal? I guess I"ll have to tune the idle -1200 range with the NB?

Last edited by 88GMC1500; 11-02-2009 at 04:06 PM. Reason: changed lower AFR range
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Old 11-02-2009, 04:14 PM   #60
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Re: 350 TBI vortec heads LT4 hotcam

Typically, the VE cells for idle need to be close if not all the same. I found that looking mainly at the cells I see active at idle, then making them all the same so that when it jumps from one cell to the next it does not add a ton of fuel or vice versa. Same with timing if you do not check to use the same SA value when at idle.

Because of cam overlap and the unreliability of the AFR at low RPMs, it is really a question of how it feels vs numbers. I just did a few learns and forgot not to use the new bin, just rather cut and paste from the non-idle cells of the new learned bin. I have to go back a few learns and copy my idle cells back again.
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Old 11-02-2009, 04:23 PM   #61
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Re: 350 TBI vortec heads LT4 hotcam

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As for the yellow wire, according to the book that is the 0-1v (simulated NB) signal. The brown wire is the 0-5v (wideband). Not sure if things have changed or what, but thats what came with my kit.
You should be able to program both channels with LM programmer. I have an O-meter (Do you?) and I set both channels the same with range from 10-20 and then set ebl and the o-meter the same as well. Section 6.5 of LC-1 manual shows a picture that has tabs for both analog out 1 and 2. Set them both to use air-fuel ratio and set 0 volt = 10 and 1 volt = 20.
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Old 11-02-2009, 04:54 PM   #62
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Re: 350 TBI vortec heads LT4 hotcam

running LM Programmer 3.25 and looking at "Analog Out 1" its a 0.103v - 1.099v range which is only an AFR range of 15.01 - 14.08. This is narrow band. What I dont know is if this is a simulated voltage range or if it this is an actual narrow band inside the O2 sensor. "Analog Out 2" is 0v - 5v range wich is AFR range of 7.35 - 22.39. From what I can figure. As for the gauge, its a blue Innovative Motorsports gauge. I've attached pics of all this in case this is something new?
Attached Images
File Type: jpg tbo_AFR.jpg (97.7 KB, 7 views)
File Type: jpg afr_gauge.jpg (14.1 KB, 6 views)
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Old 11-02-2009, 04:56 PM   #63
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Re: 350 TBI vortec heads LT4 hotcam

you can program either output to be whatever you want. the one is setup default as a narrow band sym to make it easier for people to use.



just punch the numbers you want in and hit save.
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Old 11-03-2009, 10:46 AM   #64
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Re: 350 TBI vortec heads LT4 hotcam

Quote:
just punch the numbers you want in and hit save.
Yeah, what ??? said. Change and click on program rather than save. Change, program, then switch to the Analog Out 2. Switch back and forth to make sure your changes were saved. I had some issues with mine and it took more than once to get my values to appear on the LM_Programmer.


You would not want to use the LC-1 as a NB unless you place it at the stock sensor location (Correct me if I am wrong). The WB should be just in front of the cat or even further back if you do not have a cat. Once you get the motor dialed in, you could use the LC-1 as a narrow band if you are going to run closed loop. Some at TGO like the better accuracy of the LC-1 to control closed loop. However, you loose the WB functionality. Since I am not moving to CA now, the cat is gone and I just run open loop.

You got the better gauge. I went cheap and got the Moate's O-meter. Works ok but when it is really cold it does not work until it warms up??

Once you have that all squared away, you should be able to have the gauge, ebl and the logworks to read. You would need another usb to serial to see all at once or another lappy like I did. Then you can play around with the advanced settings for the analog outputs to complicate things even more

Last edited by graebz28; 11-03-2009 at 10:50 AM.
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Old 11-03-2009, 10:52 AM   #65
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Re: 350 TBI vortec heads LT4 hotcam

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Originally Posted by alvanwie View Post
graebz28,

Glad it helped. Are you running a similar combo? I don't think any major changes would be required for a stick, just watch for knock counts when shifting. Good luck at the track. Let us know how it goes.

Al
Yes, very close but I have some waaaaay to big of heads but I got them cheap! Running GM TBI manifold, 2055 hookers, real 90 lb injectors .. rest in sig. I can't believe I am not hitting 100 MAP though. I think the intake might be the culprit. Thanks again. My tires were bad already but now they are showing the steel radials. I did not make it out to the track unfortunately. I just bought a winter car so I am going to put on my full drag suspension and slicks. I'll just drive it to the track the next couple weekends weather permitting.
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Old 11-03-2009, 10:03 PM   #66
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Re: 350 TBI vortec heads LT4 hotcam

Thanks for the LC-1 help, I see exactly what ??? said and now realize that the defaults are dumbed down a bit.

Question for the guys who have successfully tuned more than once.... I notice that all or rBOB's VE tables produce a nice smooth 3D graph. Mine looks horrendous although its running better and better as I get close. I'm just wondering if the end result is a nice smooth graph with numbers from the lower left increasing as you go up and right or is that just for stock cams?
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Old 11-03-2009, 10:06 PM   #67
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Re: 350 TBI vortec heads LT4 hotcam

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Yes, very close but I have some waaaaay to big of heads but I got them cheap! Running GM TBI manifold, 2055 hookers, real 90 lb injectors .. rest in sig. I can't believe I am not hitting 100 MAP though. I think the intake might be the culprit. Thanks again. My tires were bad already but now they are showing the steel radials. I did not make it out to the track unfortunately. I just bought a winter car so I am going to put on my full drag suspension and slicks. I'll just drive it to the track the next couple weekends weather permitting.
Yes I saw your earlier comment about only hitting 94kpa. Does it read 100 with key on/engine off? At what rpm does it drop to 94kpa?

Mine typically will be at 100kpa at WOT low rpm and will taper off to about 97kpa at about 5000rpm. I have been thinking about going to a single plane manifold, but I have seen mixed results used with tbi.
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Old 11-03-2009, 10:24 PM   #68
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Re: 350 TBI vortec heads LT4 hotcam

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Originally Posted by 88GMC1500 View Post
Thanks for the LC-1 help, I see exactly what ??? said and now realize that the defaults are dumbed down a bit.

Question for the guys who have successfully tuned more than once.... I notice that all or rBOB's VE tables produce a nice smooth 3D graph. Mine looks horrendous although its running better and better as I get close. I'm just wondering if the end result is a nice smooth graph with numbers from the lower left increasing as you go up and right or is that just for stock cams?
You will want to end up with a fairly smooth curve. However, normally you will see max VE at the your peak torque RPM then the VE will taper off at higher RPMs. Going from low kpa to high kpa, it will normally be a fairly steep slope initially and flatten out more at high kpa values.
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Old 11-04-2009, 01:02 AM   #69
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Re: 350 TBI vortec heads LT4 hotcam

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Yes I saw your earlier comment about only hitting 94kpa. Does it read 100 with key on/engine off? At what rpm does it drop to 94kpa?

Mine typically will be at 100kpa at WOT low rpm and will taper off to about 97kpa at about 5000rpm. I have been thinking about going to a single plane manifold, but I have seen mixed results used with tbi.
Yep, hits 100 at key on. Talking with some local tuners who were suggesting hitting the limit of the TBI. I agree about restriction but think it is more in the manifold if anything. Single plane could be an option for me cause the 200cc intake runners push the power band up. The LT-4 makes max torque at 5000 and max HP at 5000 (On a ZZ4 longblock http://www.cis.udel.edu/~davis/z28/buildup/cam/ ). Add the huge heads and now fuel velocity ain't happening down low so a manifold with a 6500 powerband would be better.

Ya got me looking now and I found a perfect solution for under 150. Check out http://www.summitracing.com/parts/PF...8/?image=large

Never heard of the brand, but it looks like a pretty cool piece with a 1500-6500 powerband, is still dual plane and appears to be heated/not air gap.

It also has a note that 96+ blocks do not have a water bypass in the block. Does that mean my current gmpp manifold is not getting heated by coolant from my L31 block??

Fck, time to sell all this stuff and just build my 406.
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Old 11-04-2009, 10:20 AM   #70
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Re: 350 TBI vortec heads LT4 hotcam

Quote:
Question for the guys who have successfully tuned more than once.... I notice that all or rBOB's VE tables produce a nice smooth 3D graph. Mine looks horrendous although its running better and better as I get close. I'm just wondering if the end result is a nice smooth graph with numbers from the lower left increasing as you go up and right or is that just for stock cams?

Be aware EBL uses a smoothing factor to make nice those tables.
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Old 11-04-2009, 11:52 AM   #71
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Re: 350 TBI vortec heads LT4 hotcam

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Yep, hits 100 at key on. Talking with some local tuners who were suggesting hitting the limit of the TBI. I agree about restriction but think it is more in the manifold if anything. Single plane could be an option for me cause the 200cc intake runners push the power band up. The LT-4 makes max torque at 5000 and max HP at 5000 (On a ZZ4 longblock http://www.cis.udel.edu/~davis/z28/buildup/cam/ ). Add the huge heads and now fuel velocity ain't happening down low so a manifold with a 6500 powerband would be better.

Ya got me looking now and I found a perfect solution for under 150. Check out http://www.summitracing.com/parts/PF...8/?image=large

Never heard of the brand, but it looks like a pretty cool piece with a 1500-6500 powerband, is still dual plane and appears to be heated/not air gap.

It also has a note that 96+ blocks do not have a water bypass in the block. Does that mean my current gmpp manifold is not getting heated by coolant from my L31 block??

Fck, time to sell all this stuff and just build my 406.
I believe that manifold is a knockoff of the airgap design.

The older blocks had a small thermostat bypass port built into the block. This allows a small amount of coolant flow so the thermostat see a more typical representation of coolant temps in the block rather than a stagnet pool of coolant below the t-stat.

On a true vortec engine the bypass is built into the manifold as part of the t-stat housing and most of the blocks do not have the bypass port.

So... with these aftermarket vortec manifolds if you use the newer block some sort of bypass is required so the t-stat sees the actual coolant temps otherwise you end up with hotspots in the engine.

Typically they bypass from the manifold to a water pump port. In my case there was no port on the water pump, so I simply drilled a couple of 1/4" holes in the edge of the t-stat to provide a small amount of bypass.

Last edited by alvanwie; 11-04-2009 at 11:56 AM.
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Old 11-04-2009, 12:01 PM   #72
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Re: 350 TBI vortec heads LT4 hotcam

I have been having issues with my temp dropping drastically from 180 to 150. Would hooking up one of the ports on the intake to the water pump port help this issue? The engine runs super cool, there is a 195 t-stat and I"ve replaced it 3 times now becuase the engine runs more like 175 unless sitting at a traffic light when it will go to the 195 before the t-stat opens and kicks the fans on.

I was not sure of the water pump port was a an outlet or an inlet. If its an outlet, I'm just not sure of the bypass will create a loop around the t-stat and make my condition worse.?
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Old 11-04-2009, 02:34 PM   #73
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Re: 350 TBI vortec heads LT4 hotcam

Yes, I believe you need an inlet port on the pump so you get coolant flow circulating through the engine. However, if you are using a pre 1996 block this should not be an issue because of the port in the block. Typically with the post 1996 block if no bypass is provided the t-stat will open too late, the temp guage may show too low with the t-stat closed (depending on where it is located) and you may actually hear pockets of boiling coolant at different points in the heads.

Just looked back at your original post and see that you are using a post 1996 block. You do need to provide a bypass. I would say the easiest thing to do is to drill a couple of 1/4" or 3/16" holes in the t-stat flange.
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Old 11-04-2009, 02:54 PM   #74
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Car: 88 1/2 Ton pickup
Engine: vortec 350, LT4 HotCam
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Re: 350 TBI vortec heads LT4 hotcam

The block is a 96-00 vortec truck block. CTS sensor for the ECM is in the front top of the manifold, and dash temp gauge sensor in the driver side front head. I can try doing the loop thing, other than that, Im pretty much ready to do the old cardboard in front of the radiator trick, I had to admit.
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Old 11-04-2009, 03:18 PM   #75
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Join Date: Oct 2005
Location: Dyer, In
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Car: 91 Camaro RS
Engine: 355 Vortec
Transmission: 700r4
Axle/Gears: 3.42

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Re: 350 TBI vortec heads LT4 hotcam

You are running the risk of cooking that engine. Just drill a couple of 1/4" or 3/16" holes in the t-stat flange.
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Pacesetter Ceramic Coated headers
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