Engine 92lx. Gt40x heads and air injection provisons

Jul 15, 2018
59
5
18
34
Port Mcnicoll Ontario
#1
Well so many people aay that the gt40x heads dont have air injection provisions. But every picture i look at shows different.. If the gt40x turbo swirls dont have air injection then why do u need thermactor plugs ??? Also what are the holes on the heads that are in the same spots as the trickflow heads and even e7s?? Lmr says they dont have the holes for the air injection. But every picture ive seens shows different. Im far from blind and to me they look like the thermactor ports for air injection... Can anyone who owns a pair of these heads tell me if those holes are infact the injection holes? And if they arnt then why do u need thermactor screws for them???
 

Attachments

  • Sponsors (?)

Boostedpimp

10 Year Member
May 8, 2003
638
135
74
NJ
#2
The three wholes are for the accessory brackets. Not sure what the smaller whole closes to the valve cover area would be fore but my tfs heads don't have that whole and I wouldn't assume it is injection port.
 

Mustang5L5

Car used in adult film "Highway Gangbang-InDaButt"
SN Certified Technician
Feb 18, 2001
28,687
5,609
224
Massachusetts
#3
You would need to actually look in the exhaust ports of the heads and see if they are actually drilled through. The inserts are needed because the heads are machined to be mounted on either side and you need them to install accessories.
 
Jul 15, 2018
59
5
18
34
Port Mcnicoll Ontario
#4
The three wholes are for the accessory brackets. Not sure what the smaller whole closes to the valve cover area would be fore but my tfs heads don't have that whole and I wouldn't assume it is injection port.
Well i kno the trickflow 170s have the air injection and egr. Same with afrs. But ive also seen a set of gt40x heads on a car with the air injection tube attached. Thats why im asking. Im just tryin to figure out on why a thermactor plug is needed if the hole isnt drilled... I duno im just tryin to figure this out cause im in the middle of shopping for heads. And id like to have the gt40xs instead of the afrs or tfs... Im even debating on deleting the tab/tad and just running my diverter valve to my cats and have the air injection vent to atmosphere. Emissions where im from just got scrapped so my build plans have changed..
 
Jul 15, 2018
59
5
18
34
Port Mcnicoll Ontario
#5
Well i kno the trickflow 170s have the air injection and egr. Same with afrs. But ive also seen a set of gt40x heads on a car with the air injection tube attached. Thats why im asking. Im just tryin to figure out on why a thermactor plug is needed if the hole isnt drilled... I duno im just tryin to figure this out cause im in the middle of shopping for heads. And id like to have the gt40xs instead of the afrs or tfs... Im even debating on deleting the tab/tad and just running my diverter valve to my cats and have the air injection vent to atmosphere. Emissions where im from just got scrapped so my build plans have changed..
Also if u look at the two holes next to the valve cover. They are perfect match for the air tube
 

John Dirks Jr

5 Year Member
Jun 28, 2013
1,963
728
164
54
Maryland
#6
If you dont have to deal with emissions, just ditch the air pump and related tubes, plug the back of the heads and port on cats if needed. Keep the EGR if you can.
 
Jul 15, 2018
59
5
18
34
Port Mcnicoll Ontario
#10
I called lmr. Since they are the only site that sells them. But theyre tech dept is dumb. Thry think a t5 is a m50d lol. And i honestly cant get a straight answer from them
Lmr doesnt actually kno squatt. When u ask a question they dont actually look it up. They resort to their site and read the info off it. If it says that the gt40x heads have bigg titties thats what they will repeat. If u get what i mean. The only way im actually gonne be able to find out is to either find someone who has them and see for sure. Or order them and see if they do have them.. As for ditching the emissions. I would do that if i had a way to keep the CEL from poppin codes and resorting to the flow tables...
 

Mustang5L5

Car used in adult film "Highway Gangbang-InDaButt"
SN Certified Technician
Feb 18, 2001
28,687
5,609
224
Massachusetts
#12
Here are my TFS170 heads, can you please circle where the air injection ports
I actually think my 170's do have the ports. I'll drag a head out this weekend and see.

Edit. They do.

IMG_0214.JPG

IMG_0218.JPG
 
Last edited:

Dan02gt

5 Year Member
Mar 2, 2003
465
187
83
39
Greenville, NC
#13
According to the Summit Reviews they do not have provisions for the air injection and EGR.

Outside of the price any reason you want to use these heads? Both the AFR 165s and TFS 170 flow better and have the air ports.
 

wiseguyk

Active Member
Sep 23, 2016
263
58
48
Florida
#14
I have a FRPP crate engine with GT40x heads and can confirm that they do have the thermactor air ports on them.

I know this because I assumed they didn't, until I fired it up for the first time and exhaust/smoke was pouring out the back of the heads :doh:

Thankfully I already had plugs in the old engine so I just swapped them over and all was good.