Any running doug thorley headers?

[bangotwango]

Close to making a move on a set of thorleys for my 05 denali from bb. Anyone have any experience with them? Install ease/performance/quality would be my main concerns.

Thanks in advance.

 

[Sprayed99]

Close to making a move on a set of thorleys for my 05 denali from bb. Anyone have any experience with them? Install ease/performance/quality would be my main concerns.

Thanks in advance.

I have installed about every header out there for the 99-07 trucks and and like body style SUVs. The thorleys fall into the same category as a pace setter coated headers as far as fit, quality, and performance.

My favorite choice of tubes for these model SUVs is american racing headers. Next would be stainless works.

 

[Xav8r]

My favorite choice of tubes for these model SUVs is american racing headers. Next would be stainless works.

Since I'm considering my options, and you have some experience; which of the two American Racing Header sizes (1 3/4" or 1 7/8") do you recommend for a '01 Tahoe 4WD?

 

[Sprayed99]

Since I'm considering my options, and you have some experience; which of the two American Racing Header sizes (1 3/4" or 1 7/8") do you recommend for a '01 Tahoe 4WD?

anything NA 1 3/4 anything that you plan on running nitrous or forced induction I would go 1 7/8

 

[ATL]

anything NA 1 3/4 anything that you plan on running nitrous or forced induction I would go 1 7/8

agreed!

 

[Xav8r]

anything NA 1 3/4 anything that you plan on running nitrous or forced induction I would go 1 7/8

Thanks for the suggestions guys ... gives me the opportunity to plan ahead now. I'm seriously considering FI (1900TVS) however am going to have a compression and leak down done before I start throwing money at this truck.

So the next obvious question for you guys to help me learn; is there anything adverse in putting the 1 7/8" on a normally aspirated truck (should I decided not to go FI in the future)? Will this kill any performance? etc ...

Thanks again

 

[Sprayed99]

Thanks for the suggestions guys ... gives me the opportunity to plan ahead now. I'm seriously considering FI (1900TVS) however am going to have a compression and leak down done before I start throwing money at this truck.

So the next obvious question for you guys to help me learn; is there anything adverse in putting the 1 7/8" on a normally aspirated truck (should I decided not to go FI in the future)? Will this kill any performance? etc ...

Thanks again

on a 5.3L i wouldnt do it on a 6.0 it won't have that much of an effect on it. In fact running the 1 3/4 on a little 5.3 with a 1900 wouldnt be all that bad either.

 

[hidpositive]

Thanks for the suggestions guys ... gives me the opportunity to plan ahead now. I'm seriously considering FI (1900TVS) however am going to have a compression and leak down done before I start throwing money at this truck.

So the next obvious question for you guys to help me learn; is there anything adverse in putting the 1 7/8" on a normally aspirated truck (should I decided not to go FI in the future)? Will this kill any performance? etc ...

Thanks again

I am in the same boat as you, I want to do an exhaust on my 06 denali this year and set it up for H/C/I next spring. will the 1 7/8's be an issue if the car doesnt get a blower right away? I would hate to waste money like that and change the headers twice if i might only loose a little performance while shes N/A...
-Gary

 

[Xav8r]

Well I've read ... and read ... and read some more. Although I do not have any real experience with this subject and am by no stretch of the imagination knowledgeable, I have talked with a few people in a few forums as well as a few of the manufacturers.

For my situation and preferences ('01 5.3 4WD daily driver w 184k, all the normal bolt-ons & BB tuned, n/a for now, that I use to tow a heavier boat up the steep grades of California) the list of possibilities I considered is; American Racing Headers, Dynatechs, Doug Thorleys, LaMontePerformanceParts, Pacesetter, and CalSpeed.

I'm about to pull the trigger on the Thorley's because of the preservation and enhancement of performance in the lower RPM ranges (where my engine spends 90% of it's life) as well as the CA legality issue. However I am also extremely impressed with the Dynatechs and might have a last minute change of heart over to these.

I don't expect this will help much as it doesn't include any data or specs, but it's the best fast summary attempt of my journey through the choices for anyone who wants to compare.