Texas Speed ported heads - need CFM flow rates
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I'm Batman..
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From: Lehigh Acres FL
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Texas Speed ported heads - need CFM flow rates
TSP offers CNC ported cylinder heads for the LT1. This service requires you to send in your existing LT1 heads For them to port them. Unfortunately they do not list the flow rates for this service on what the expected flow will be afterwards. Anyone know what the flow rates are?
They also offer replacement aftermarket PRC heads and notate on the site the flow rate for those but that is not the same as what I am asking.
Thanks in advance guys
Ant
They also offer replacement aftermarket PRC heads and notate on the site the flow rate for those but that is not the same as what I am asking.
Thanks in advance guys
Ant
Drifting
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TSP offers CNC ported cylinder heads for the LT1. This service requires you to send in your existing LT1 heads For them to port them. Unfortunately they do not list the flow rates for this service on what the expected flow will be afterwards. Anyone know what the flow rates are?
They also offer replacement aftermarket PRC heads and notate on the site the flow rate for those but that is not the same as what I am asking.
Thanks in advance guys
Ant
They also offer replacement aftermarket PRC heads and notate on the site the flow rate for those but that is not the same as what I am asking.
Thanks in advance guys
Ant
Thread Starter
I'm Batman..
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From: Lehigh Acres FL
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Team Owner
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From: cookeville tennessee
Drifting
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ls7 heads flow around 340-345 stock
Thread Starter
I'm Batman..
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From: Lehigh Acres FL
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Texas speed was running a special.. they had just finished there CNC program! Factory heads flow around 300 (less then a stock Ls3 head) despite the 12 degree valve angle.. I think I paid less then a thousand and had them milled at the same time..
ls7 heads flow around 340-345 stock
ls7 heads flow around 340-345 stock
Drifting
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I talked with Lonnie at TSP and he confirmed that at .650 they flow 358CFM. Those are some great numbers! That, coupled with the five angle valve job, and skimming the head (milling if your going NA) cost me less than a grand. They are even going to install my Vengeance Racing springs, retainers, and keepers and set the spring height for me! Woohoo! Im ecstatic! All I have to do is ship them my heads now.
I'm 12.1 CR at around 12lbs on stock bottom end lt1.. I run flex fuel and I'm decent at tuning lol
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Stock LT1 heads flow....
.60 lift-----285 I/208 E
.65 lift-----291 I/210 E
but the ported LT1 heads from Texas Speed flow....
.60 lift-----345 I/226 E
.65 lift-----358 I/228 E
Stock LS3 heads flow....
.60 lift-----316 I/189 E
The PRC LS3 heads flow.....
.60 lift-----358 I/235 E
.65 lift-----366 I/240 E
As you can see the ported C6 LS3 heads flow better than the ported LT1 heads.
A stock C6 Z06 LS7 head flows....
.60 lift-----351 I/209 E
.65 lift-----353 I/204 E
A PRC265 LS7 head flows....
.60 lift-----383 I/235 E
.65 lift-----388 I/241 E
A PRC285 LS7 head flows....
.60 lift-----386 I/235 E
.65 lift-----393 I/241 E
Last edited by JoesC5; Apr 20, 2017 at 06:57 PM.
Thread Starter
I'm Batman..
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From: Lehigh Acres FL
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I don't think the stock heads are that good. If they were, the LT1 would have around 500 HP instead of 460 HP.
Stock LT1 heads flow....
.60 lift-----285 I/208 E
.65 lift-----291 I/210 E
but the ported LT1 heads from Texas Speed flow....
.60 lift-----345 I/226 E
.65 lift-----358 I/228 E
Stock LS3 heads flow....
.60 lift-----316 I/189 E
The PRC LS3 heads flow.....
.60 lift-----358 I/235 E
.65 lift-----366 I/240 E
As you can see the ported C6 LS3 heads flow better than the ported LT1 heads.
A stock C6 Z06 LS7 head flows....
.60 lift-----351 I/209 E
.65 lift-----353 I/204 E
A PRC265 LS7 head flows....
.60 lift-----383 I/235 E
.65 lift-----388 I/241 E
A PRC285 LS7 head flows....
.60 lift-----386 I/235 E
.65 lift-----393 I/241 E
Stock LT1 heads flow....
.60 lift-----285 I/208 E
.65 lift-----291 I/210 E
but the ported LT1 heads from Texas Speed flow....
.60 lift-----345 I/226 E
.65 lift-----358 I/228 E
Stock LS3 heads flow....
.60 lift-----316 I/189 E
The PRC LS3 heads flow.....
.60 lift-----358 I/235 E
.65 lift-----366 I/240 E
As you can see the ported C6 LS3 heads flow better than the ported LT1 heads.
A stock C6 Z06 LS7 head flows....
.60 lift-----351 I/209 E
.65 lift-----353 I/204 E
A PRC265 LS7 head flows....
.60 lift-----383 I/235 E
.65 lift-----388 I/241 E
A PRC285 LS7 head flows....
.60 lift-----386 I/235 E
.65 lift-----393 I/241 E
Drifting
Joined: Jul 2005
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Drifting
Joined: Jul 2005
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Yes 12.1 CR/stock cam and 12lbs of boost...
as time goes on you'll see higher comprsssion on a DI motor pretty normal..
LT4 is 10.1 and is ULTRA safe on a DI engine.. much like being 9.1 on a port injection motor (LS9)
It all goes back to proper fueling and spark.. your tuning window is much smaller on a higher CR engine so you have to be ok top of the tune..
I run e60 and meth (10gph) and max timing is 12 degrees and little less at peak tq and a simple 8 on 93.
With a Cam I would do even more compression and be able to get away with it due to dynamic compression
as time goes on you'll see higher comprsssion on a DI motor pretty normal..
LT4 is 10.1 and is ULTRA safe on a DI engine.. much like being 9.1 on a port injection motor (LS9)
It all goes back to proper fueling and spark.. your tuning window is much smaller on a higher CR engine so you have to be ok top of the tune..
I run e60 and meth (10gph) and max timing is 12 degrees and little less at peak tq and a simple 8 on 93.
With a Cam I would do even more compression and be able to get away with it due to dynamic compression
Thread Starter
I'm Batman..
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From: Lehigh Acres FL
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T/A, a couple of questions about your TSP heads..
1. Did your intake runners have a small hole in them where they were ported out exposing the bottom of the rocker bolt hole/threads? Mine have a small pinhole area on each of the intake runners like this. I read online that using some simple thread sealer will take care of this, I'm just not sure if that is normal or not.
2. Did you get any bench flow test results for your heads back from them with your heads showing how they performed?
3. What did the porting job look like? Were all areas of the ports touched by the CNC machine? Mine appears to have several areas that were not touched by the machine, and that may just be because there's no restriction there. It doesn't look like the actual ports where the gaskets mate up are any bigger.
Thanks
Ant
1. Did your intake runners have a small hole in them where they were ported out exposing the bottom of the rocker bolt hole/threads? Mine have a small pinhole area on each of the intake runners like this. I read online that using some simple thread sealer will take care of this, I'm just not sure if that is normal or not.
2. Did you get any bench flow test results for your heads back from them with your heads showing how they performed?
3. What did the porting job look like? Were all areas of the ports touched by the CNC machine? Mine appears to have several areas that were not touched by the machine, and that may just be because there's no restriction there. It doesn't look like the actual ports where the gaskets mate up are any bigger.
Thanks
Ant
Drifting
Joined: Jul 2005
Posts: 1,646
Likes: 188
T/A, a couple of questions about your TSP heads..
1. Did your intake runners have a small hole in them where they were ported out exposing the bottom of the rocker bolt hole/threads? Mine have a small pinhole area on each of the intake runners like this. I read online that using some simple thread sealer will take care of this, I'm just not sure if that is normal or not.
2. Did you get any bench flow test results for your heads back from them with your heads showing how they performed?
3. What did the porting job look like? Were all areas of the ports touched by the CNC machine? Mine appears to have several areas that were not touched by the machine, and that may just be because there's no restriction there. It doesn't look like the actual ports where the gaskets mate up are any bigger.
Thanks
Ant
1. Did your intake runners have a small hole in them where they were ported out exposing the bottom of the rocker bolt hole/threads? Mine have a small pinhole area on each of the intake runners like this. I read online that using some simple thread sealer will take care of this, I'm just not sure if that is normal or not.
2. Did you get any bench flow test results for your heads back from them with your heads showing how they performed?
3. What did the porting job look like? Were all areas of the ports touched by the CNC machine? Mine appears to have several areas that were not touched by the machine, and that may just be because there's no restriction there. It doesn't look like the actual ports where the gaskets mate up are any bigger.
Thanks
Ant
2)I did not!! Texas speed always has a solid cylinder head (especially for the money)
3) there CNC job doesn't touch everywhere... it would need to be touched up by hand if you wanted that!! I think the head could be improved a little, but for what you get it's solid!! They took the bare minimum bc they didn't want to increase
port volume too much.
Last edited by T/A KID; May 19, 2017 at 04:36 PM.
Thread Starter
I'm Batman..
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From: Lehigh Acres FL
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1) yes!! That's common!! Just use some "right stuff" or similar sealant
2)I did not!! Texas speed always has a solid cylinder head (especially for the money)
3) there CNC job doesn't touch everywhere... it would need to be touched up by hand if you wanted that!! I think the head could be improved a little, but for what you get it's solid!! They took the bare minimum bc they didn't want to increase
port volume too much.
2)I did not!! Texas speed always has a solid cylinder head (especially for the money)
3) there CNC job doesn't touch everywhere... it would need to be touched up by hand if you wanted that!! I think the head could be improved a little, but for what you get it's solid!! They took the bare minimum bc they didn't want to increase
port volume too much.
Thanks man!
Ant