downpipe or dutt neck?

[oc192]

When I first bought my car a year ago, it had some major issues. It would knock at only 5 lbs of boost. Fast forward 1 year later and I have a lot of the bugs worked out, now running 15 lbs of boost with no knock (have to mix in 100 octane of happy juice). I have replaced fuel pump, injectors, hotwire kit etc etc. Besides Alky, what mod would you go for next? Right now it is a toss up between a 3 in downpipe or a duttweiler neck.

 

[Nasty Wendy]

For immediate gains go with the duttweiler neck. More than likely you will upgrade your IC later so going with the dp will be a longer lasting investment. So the question is do you want the most bang for your buck right now (dutt neck) or are you modding for future improvements?

 

[oc192]

For immediate gains go with the duttweiler neck. More than likely you will upgrade your IC later so going with the dp will be a longer lasting investment. So the question is do you want the most bang for your buck right now (dutt neck) or are you modding for future improvements?

Thanks Wendy, modding for future improvements. My goal is to reliably achieve 11.5ish 1/4.

 

[TRICKSIXPA]

Skip the Dutt neck and go straight to a streched Innercooler if your patient you should be able to find one on the board going for $300-$500 then you would not have to worry about buying another one to reach your 11.5 goal. Yes I know people have gone over that with a Dutt neck but having a stretched innercooler
makes it easier.IMO.

 

[turbofabricator]

Down pipe. The Dutt-neck really doesn't do much more if you spend a half hour with a die grinder (or even a drill) with a carbide cutter and port about .150" from each side of the inlet. Stuff rags in it and keep it upside down, then grind away. You'd be hard pressed to find ANY gain in the Dutt neck, over doing just the porting. Clean the intercooler out at the same time. Use brake clean, and let it soak a few minutes. Slosh it around and you will be amazed at the amount of oil that is coating everything in there. It'll probably take 4-5 cans of brake clean if it's never been done before. You can also strip all the external paint off of it to make it more efficient. The stock paint is THICK and acts like a blanket. Use a light coat of flat black after stripping the old paint with Permatex spray gasket remover. Works just like paint remover. Spray it on, let it sit in the sun, then high pressure nozzle spray it with a garden hose. Rinse/repeat as needed. Save your money needed to buy and weld on the Dutt Neck for a PTE intercooler.

 

[turbo nasty]

Neither get alky.....Even though your say Beside Alky. Best performance for money spent.

 

[Rich Gio]

Neither get alky

I Know you said BESIDES Alky, but.....X2! Just put Razor's kit on mine... Went from a 13.2 @ 100MPH (17# boost) to a 12.6 @ 106 MPH (22# boost). Best Mod I've done to date!

You could also port the turbo elbow... supposed to give you similar gains as the downpipe into the 11's.

 

[williamsGN]

Downpipe, no need trying to increasing turbo flow through the intercooler if you can't first increase the exhaust flow.

 

[tzque]

Can you please explain how the alky kit works and why get both the alky kit and the down pipe . My car was stock but as then go I upgrade . I am surronded by trash talking kids in hondas and even though my head tells me not to race them . Right place right time I need to make sure I can beat them

 

[CardBoardHero]

I am surronded by trash talking kids in hondas and even though my head tells me not to race them . Right place right time I need to make sure I can beat them

Do like I do... Show them something they can't do.... Take off with 3 of your friends riding with you. I bust on a friend with a rx7 all the time, because he doesn't have room for trash talk AND his girlfriend in the car

By the way... I cleaned my intercooler this spring after purchasing the car... Even that one little thing makes a difference. I would recommend new hoses and clamps at the same time.

 

[williamsGN]

Can you please explain how the alky kit works and why get both the alky kit and the down pipe . My car was stock but as then go I upgrade . I am surronded by trash talking kids in hondas and even though my head tells me not to race them . Right place right time I need to make sure I can beat them

Alky kit is triggered at a set boost psi and sprays alky / methanol into the up pipe which cools the air charge in your motor preventing detonation. This allows you to run higher boost levels without the need for race fuel.

The stock downpipe and elbow are very restrictive, I noticed a difference when I added a downpipe to my first GN in stock trim. In fact I would say the stock downpipe set up is more restrictive then the stock exhaust and would replace the pipe before I even worried about the muffler system.

 

[BobbyBuick]

first step fuel, 2nd step exhaust... i would gut the cat or loose it and get a DP.I ran 11.60s on a stock IC no neck mod.I have a nice DP for sale that will look like a stocker stainless steel 3" for 285.00

 

[oc192]

Thanks for the replies, based on this thread I am going with the downpipe. My next questoin is what type should I get? I want to be able to adjust the boost with a manual boost controller mounted in the car. Will I need a downpipe with an external wastegate, internal wastegate, or does that matter. ALso, is the wastegate solenoid on the passenger valve cover the same thing?

 

[williamsGN]

I've had ext & int and both had boost controllers in the car. If you have an external you can then lose the solenoid on the valve cover. Externals will cost more, but my external stays more consistent boost wise than the internal I had.

 

[Nasty Wendy]

External vs Internal will depend on your goals. How much power do plan on making?

 

[oc192]

External vs Internal will depend on your goals. How much power do plan on making?

I would like to make between 400-500 hp when it is all said and done.......which will be a couple years out

 

[turbofabricator]

Intergral wastegate up to 750+ HP.

 

[Roger]

I've compared Dutt neck to stock & seen no difference, however, the TRs don't all respond the same.
The TH downpipe was a big improvement.

 

[turbofabricator]

Ken Duttweiler himself claimed that the increase in power stated was due to loosening the compressor housing and rotating down to align the inlet/outlet better which in turn increased spring pressure on the wastegate actuator which increased boost 2 psi. This was a LOOOOONG time ago. Wish I remembered where he stated this.

 

[Rich Gio]

Ken Duttweiler himself claimed that the increase in power stated was due to loosening the compressor housing and rotating down to align the inlet/outlet better which in turn increased spring pressure on the wastegate actuator which increased boost 2 psi. This was a LOOOOONG time ago. Wish I remembered where he stated this.

I did not see any real HP gains by going to the Dutt neck. That being said I DID see a decrease in lag and "gained" 2 psi of boost at the same actuator setting. Seemed to spool up faster at the line as well.