TTI vs Dougs

-
gabe380

gabe380

Active Member
Joined
Nov 4, 2015
Messages
34
Reaction score
10
Location
Portland, Or
I know that there are countless threads about this, but I have a question that I haven't been able to find an answer to yet.

Both TTI and Doug's offer a ceramic coating option, but TTI also has the option for a "thermal barrier" coating to be applied to the inside of the headers. Supposedly this thermal barrier creates better airflow through the headers, as well as reducing the overall underhood temp.

Just curious if anyone has used both of these products, and has noticed any worthwhile improvement/benefits with the "thermal barrier" version of the TTI's.

I would just buy the TTI's and forget about it, if it weren't for the fact that TTI says that their 340 headers won't work on a 318. I have a 318 now, but will likely be swapping to a 340 at some point, and really don't want to have to buy a second set of expensive headers.


Gabe
 
gabe380 said:
I know that there are countless threads about this, but I have a question that I haven't been able to find an answer to yet.

Both TTI and Doug's offer a ceramic coating option, but TTI also has the option for a "thermal barrier" coating to be applied to the inside of the headers. Supposedly this thermal barrier creates better airflow through the headers, as well as reducing the overall underhood temp.

Just curious if anyone has used both of these products, and has noticed any worthwhile improvement/benefits with the "thermal barrier" version of the TTI's.

I would just buy the TTI's and forget about it, if it weren't for the fact that TTI says that their 340 headers won't work on a 318. I have a 318 now, but will likely be swapping to a 340 at some point, and really don't want to have to buy a second set of expensive headers.


Gabe
Click to expand...
I'm not sure about the coating part of your question, but i can't understand why TTI would claim that the headers won't work on a 318.
They may not be optimum for the port size difference, but claiming that they ''won't work'' on a 318 is hogwash.
There is lots of meat on the sealing surface of a 318 head to accommodate the bigger tubes and flange.
In fact, i do have a cheaper brand of header on my A-Body 318 (Flowtech, don't buy these, they are designed for a B-Body i found out later!) that is also designed for a 340/360 engine and had no issues with the sealing to the head issue, my issues were hitting the steering box and coupler, torsion bars, and oil filter. Cheap headers are a nightmare to say the least...........
I would say that a 318 sized port header wouldn't work on a 340 or 360 port size engine, not the other way around.
I would call TTI and i bet they say that it's a misprint.
 
Last edited:
TTI offers to "fill in" the sections of the exhaust flange that does not correctly contact the head exhaust port. Solution; get the option for extra $, when you convert to the 340 simply grind out the added section. Port matched of course.

upload_2019-4-5_13-23-25.png


upload_2019-4-5_13-24-23.png
 
Dartnut said:
I'm not sure about the coating part of your question, but i can't understand why TTI would claim that the headers won't work on a 318.
They may not be optimum for the port size difference, but claiming that they ''won't work'' on a 318 is hogwash.
There is lots of meat on the sealing surface of a 318 head to accommodate the bigger tubes and flange.
In fact, i do have a cheaper brand of header on my A-Body 318 (Flowtech, don't buy these, they are designed for a B-Body i found out later!) that is also designed for a 340/360 engine and had no issues with the sealing to the head issue, my issues were hitting the steering box and coupler, torsion bars, and oil filter. Cheap headers are a nightmare to say the least...........
I would say that a 318 sized port header wouldn't work on a 340 or 360 port size engine, not the other way around.
I would call TTI and i bet they say that it's a misprint.
Click to expand...
I thought the same thing, until I called them last week. They said that the 340 headers almost always leak on 273/318's, and that's why they make a specific header for the smaller engines.
 
I have never heard or read a claim that a thermo barrier or other type coating on the inside of the header tube will improve flow and HP.

Now THATS Hogwash!
 
Hey Gabe,

Here's what I found on TTi's site,

"An appealing silver high-luster finish applied to the steel surface to protect against rust, corrosion and withstands temperatures up to 1200°F. Exceeding this temperature will result in discoloration of the header tubes. The thermal barrier is a protective inside coating which increases part longevity by reducing under-hood temperatures by 50 degrees protecting component parts from thermal fatigue."

No mention of performance enhancements unless I missed it somewhere else on their website.

Personally, I found TTI products to be excellent and they fit perfectly!!

If they told me a particular header won't fit correctly, I'd believe them .

I've followed a lot of threads on this and other forums and it is rarely that you hear a complaint about TTi with the exception of pricing.

I have TTI on my car and I couldn't be happier with the product or their service.

My 2 cents....
 
gabe380 said:
I thought the same thing, until I called them last week. They said that the 340 headers almost always leak on 273/318's, and that's why they make a specific header for the smaller engines.
Click to expand...
Well, i learned something new today then................
Thanks!
 
gabe380 said:
I know that there are countless threads about this, but I have a question that I haven't been able to find an answer to yet.

Both TTI and Doug's offer a ceramic coating option, but TTI also has the option for a "thermal barrier" coating to be applied to the inside of the headers. Supposedly this thermal barrier creates better airflow through the headers, as well as reducing the overall underhood temp.

Just curious if anyone has used both of these products, and has noticed any worthwhile improvement/benefits with the "thermal barrier" version of the TTI's.

I would just buy the TTI's and forget about it, if it weren't for the fact that TTI says that their 340 headers won't work on a 318. I have a 318 now, but will likely be swapping to a 340 at some point, and really don't want to have to buy a second set of expensive headers.


Gabe
Click to expand...

rumblefish360 said:
I have never heard or read a claim that a thermo barrier or other type coating on the inside of the header tube will improve flow and HP.

Now THATS Hogwash!
Click to expand...


Anything that decreases the diameter inside the pipe will not flow as much as the larger pipe...

If you are going to run a thermal barrier, put it on the OUTSIDE of the pipe so it doesn't restrict flow....

I gotta go with Rumblefish on this one...
 
The thermal barrier will cut your underhood temperatures and that is most certainly worth more power than whatever loss of inside diameter the coating might result in,the coating is not that thick,will also keep everything else in the enginecompartment alitle happier by keeping the heat where it belongs. If the difference is measurable? dont know,never measured,but i know for a fact that many years ago i swaped from just painted headers to a set of coated headers with the thermal barrier and the difference in underhood heat radiation was obvious.
And you want that barrier inside the tubing not on the inside considering how some headertubing seems to harden over the years due to the heatcykles..
 
As long as its an organic coating with soft pigments. Anything that comes lose near the heads is subject to reversion. Don't want anything hard or abrasive getting sucked in.

I say if you really want headers on the 318, get 318 headers. If/when you buy the 340 and install it, you can either modify or sell and got a portion of your money back.
 
Multiple sets of TTI on several different rigs. Always with the same results. Zero issues, no struggles on install and great longevity. Dougs would be my 2nd choice for sure. after that..... Good headers ain't cheap, cheap headers ain't good.
 
IMO, waste of money on the thermal stuff.

I buy coated dougs every time now. Use the autozone code and the coated are in the 560 range.
 
1Fast340 said:
The thermal barrier will cut your underhood temperatures and that is most certainly worth more power than whatever loss of inside diameter the coating might result in,the coating is not that thick,will also keep everything else in the enginecompartment alitle happier by keeping the heat where it belongs. If the difference is measurable? dont know,never measured,but i know for a fact that many years ago i swaped from just painted headers to a set of coated headers with the thermal barrier and the difference in underhood heat radiation was obvious.
And you want that barrier inside the tubing not on the inside considering how some headertubing seems to harden over the years due to the heatcykles..
Click to expand...
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^this
Also , the thickness is what /.001 to .002 thick ?. Get real.
If I were going to buy new headers, u could bet ur a$$ the they would be thermal coated !! If u think they don't work, try an A B A test with them and w/o , the engine compartment heat will make u believe other wise. Unless u got some weak *** motor that doesn't have enough h.p. to get hot .
Flaking off and going back into the engine would be about the last thing I would worry about . opinions are like --- -----, most everybody has got one , this is mine----------opinion, LOL
 
famous bob said:
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^this
Also , the thickness is what /.001 to .002 thick ?. Get real.
If I were going to buy new headers, u could bet ur a$$ the they would be thermal coated !! If u think they don't work, try an A B A test with them and w/o , the engine compartment heat will make u believe other wise. Unless u got some weak *** motor that doesn't have enough h.p. to get hot .
Flaking off and going back into the engine would be about the last thing I would worry about . opinions are like --- -----, most everybody has got one , this is mine----------opinion, LOL
Click to expand...
Yup. I don't want any ___ extra junk getting iinto my engines, and I don't beleive that coating is guarenteed to never come off when subjected to exhaust right off the head.

For thermal barrier coating, I went with the real deal on the last pair of carbon steel headers. Zirconiumdioxide.

TTI-Shorty-Driverside-cropped.jpg


TTI-Shorty-Passenger-side-031F.JPG
 
Last edited:
Underhood temperatures reduced by 100 degrees with the ceramic TTI’s vs similar cars with stock exhaust at summertime car shows. Not scientific, but did use a thermal temp gun.
 
You must log in or register to reply here.
-

Back
Top