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Tech Area => General Buick Tech => Topic started by: SuperSix on April 24 2014, 02:38:43 PM

Title: Dutt neck - worth it?
Post by: SuperSix on April 24 2014, 02:38:43 PM
Is this a viable upgrade over stock? Cost is $70 or so, then I would have to pay someone to weld it in..

Or just wait for a deal on a good used aftermarket SLIC/front mount?
Title: Re: Dutt neck - worth it?
Post by: earlbrown on April 24 2014, 02:45:12 PM
Back when that was a common mod people used to report boost jumping up 3 or 4 pounds from that neck.

That tells me you'll loose 10 ~ 15 pounds of ex manifold pressure at the set boost level. That's always a good thing.


Even a good deal on a used SLIC will be a lot more than the $100 or so it'll take to upgrade the stocker.  Plus you can always sell it for more money with the neck on it when you find that good deal.


Before I bought the neck, I'd pressure test your stock intercooler first.  No reason to put a bunch of effort into a leaky core.
Title: Re: Dutt neck - worth it?
Post by: SuperSix on April 24 2014, 03:20:08 PM
Back when that was a common mod people used to report boost jumping up 3 or 4 pounds from that neck.

That tells me you'll loose 10 ~ 15 pounds of ex manifold pressure at the set boost level. That's always a good thing.


Even a good deal on a used SLIC will be a lot more than the $100 or so it'll take to upgrade the stocker.  Plus you can always sell it for more money with the neck on it when you find that good deal.


Before I bought the neck, I'd pressure test your stock intercooler first.  No reason to put a bunch of effort into a leaky core.

Great info, just what I was looking for.

Thanks, Earl.
Title: Re: Dutt neck - worth it?
Post by: Steve Wood on April 24 2014, 05:43:39 PM
Yep

Steve

Title: Re: Dutt neck - worth it?
Post by: motorhead on April 24 2014, 09:58:13 PM
Your other option is something like this: http://www.ebay.com/itm/ALUMINUM-TURBO-35-x11-75x4-BLACK-FRONT-MOUNT-INTERCOOLER-KIT-2-5-SILVER-PIPING-/201078115194?pt=Motors_Car_Truck_Parts_Accessories&hash=item2ed1308b7a&vxp=mtr (http://www.ebay.com/itm/ALUMINUM-TURBO-35-x11-75x4-BLACK-FRONT-MOUNT-INTERCOOLER-KIT-2-5-SILVER-PIPING-/201078115194?pt=Motors_Car_Truck_Parts_Accessories&hash=item2ed1308b7a&vxp=mtr)
Title: Re: Dutt neck - worth it?
Post by: deathraider6996 on April 24 2014, 10:00:42 PM
See I've been wondering about those eBay intercoolers. Are they better than stock? Is it hard to mess up a intercooler design?. Are they worth their price?

Sent while curing depression with boost.

Title: Re: Dutt neck - worth it?
Post by: Scoobum on April 25 2014, 05:20:43 AM
You pay for what you get. Either weld a Dutt neck on a stocker...or go with a good quality SLIC like a Precision etc.
Title: Re: Dutt neck - worth it?
Post by: daveismissing on April 25 2014, 08:27:27 AM
Quote
Turbofabricator:
ACTUALLY.........The Dutt-neck ONLY gained 2 psi of boost due to Kenny having to re-clock the compressor housing to align with the new centerline of the larger neck. This, in turn, added more spring tension on the wastegate actuator. PERIOD! I have welded quite a few 2.5" Dut-Necks on over the years. They definately do not hurt performance, but I have found no substaniated gain other wise. Take a die grinder to the intercooler inlet and you can gain almost 1/2" of cross sectional area. The above info came directly from Kenny himself, shortly after he dyno tested the modification. I agree with Razor in that the CORE is the biggest restriction in the system. Step up to a PTE stock location intercooler for the best gains. (or other SLIC units available today.) The stock core is barely big enough to support 350HP. I know, I know they ARE alot of coin.
Title: Re: Dutt neck - worth it?
Post by: SuperSix on April 25 2014, 09:28:37 AM
Hmmmm
Title: Re: Dutt neck - worth it?
Post by: Steve Wood on April 25 2014, 09:59:40 AM
http://www.vortexbuicks-etc.com/ICtest.htm (http://www.vortexbuicks-etc.com/ICtest.htm)

Numbers are relative.  The two pounds drop in this test (the only near scientific test I have seen published) are a significant percentage given the magnitude of the numbers being compared.

One must keep things in perspective.  If we put a large turbo on a very fast car, the improvement would be miniscule if going from a stock IC to a big neck...but if we are talking about turbos of the 44 size on an average street car that is sneaking into the elevens, the improvement is more obvious.

Contrary to most internet commandos, one does not need a big IC or a three inch dp to run in the elevens...On the other hand, a steady supply of mullets is required to keep the Buick business in business...
Title: Re: Dutt neck - worth it?
Post by: Steve Wood on April 25 2014, 10:09:47 AM
More food for thought, Grumpy edged into the Nines on V4...and it does not look all that impressive on the test linked above...just shows how dangerous it is to make assumptions based on apples and oranges particularly when it comes to numbers.


In answer to the question above about IC design...yes it is complicated as one is trying to balance flow versus heat reduction and get even air flow across the entire core to maximize affect....
Title: Re: Dutt neck - worth it?
Post by: tb3 on April 26 2014, 09:59:58 AM
I wonder why there hasn't been a GNX Dutt necked intercooler ever been available for the aftermarket? 
Seems like that would be the ultimate for guys that wanted to go stock-ish appearing and stock mounted
Title: Re: Dutt neck - worth it?
Post by: granitestategn on April 26 2014, 10:19:23 AM
Quote
Turbofabricato r:
ACTUALLY.........The Dutt-neck ONLY gained 2 psi of boost due to Kenny having to re-clock the compressor housing to align with the new centerline of the larger neck. This, in turn, added more spring tension on the wastegate actuator. PERIOD! I have welded quite a few 2.5" Dut-Necks on over the years. They definately do not hurt performance, but I have found no substaniated gain other wise. Take a die grinder to the intercooler inlet and you can gain almost 1/2" of cross sectional area. The above info came directly from Kenny himself, shortly after he dyno tested the modification. I agree with Razor in that the CORE is the biggest restriction in the system. Step up to a PTE stock location intercooler for the best gains. (or other SLIC units available today.) The stock core is barely big enough to support 350HP. I know, I know they ARE alot of coin.
I'm confused by this one. Why would you have to re-clock the turbo to align it with the Dutt neck? I have mocked up my stocker on a piece of plywood as a jig and plan to cut off the stock neck and maintain the same centerline and distance when welding to the Dutt neck in place. I see no reason why this won't fit correctly. Why would you install it any other way?
Title: Re: Dutt neck - worth it?
Post by: Steve Wood on April 26 2014, 10:36:54 AM
I am sure there has been...a GNX intercooler is the same one used on the TTA's....as I recall, the fin spacing is the only difference between the GN and the GNX/TTA


A couple of more comments-as is so often said, we get hung up on boost which is measured in psi but what counts is how many air molecules we can push into the cylinder which is air density.  Heating air thru the turbocharging process reduces the number of molecules in a cubic foot of air....when we intercool the air charge we are trying to recover lost air density which resulted from the compression of the charge.

Coincidentally, alcohol injection does the same thing...increa ses the charge density when it vaporizes and removes heat from the air charge.

The link I posted above from Bob Dick's test used a relatively small turbo-a TA49 as I recall.  It showed a reduction in pressure drop of about 2 psi across the core under the test conditions...a nd a corresponding improvement in flow coefficient of about 40% if I divided in the right direction...th at is about what the pressure drop reflects as well.

I think it is safe to say that the big neck is a pretty good bang for the buck in a mild combo that runs mid elevens...wher eas it is a paperweight on a Nine second car....add alcohol injection and it is perfectly adequate for most people unless they want to go down to the local Wawa and compare invoices.

It's all about apples and oranges
Title: Re: Dutt neck - worth it?
Post by: Steve Wood on April 26 2014, 10:38:30 AM
Normally I would not expect to have to reclock it
Title: Re: Dutt neck - worth it?
Post by: daveismissing on April 26 2014, 03:10:27 PM
Via the study Steve linked it certainly looks like there are benefits.
I trust no one thinks I was disparaging Steve by quoting the dissenting opinion, -merely to engage the peeps in a spirited discussion. :)
.
Title: Re: Dutt neck - worth it?
Post by: Steve Wood on April 26 2014, 03:46:57 PM
certainly does not bother me...just pointing out that remarks have to be taken into context and one does not need an IC rated at 1200 hp to get good benefits on an eleven second car....

Title: Re: Dutt neck - worth it?
Post by: motorhead on April 26 2014, 08:48:48 PM
In answer to the question above about IC design...yes it is complicated as one is trying to balance flow versus heat reduction and get even air flow across the entire core to maximize affect....

For this same reason I am willing to entertain a "knock-off" eBay FMIC intercooler over a 30 year old SLIC; there are lots of 8-9 second turbo LS-engines running these eBay units.

To each their own.
Title: Re: Dutt neck - worth it?
Post by: granitestategn on April 26 2014, 08:55:08 PM
Via the study Steve linked it certainly looks like there are benefits.
I trust no one thinks I was disparaging Steve by quoting the dissenting opinion, -merely to engage the peeps in a spirited discussion. :)
.

Nope. I didn't take it that way. I just couldn't understand why you would need to change the location of the IC inlet centerline. I think you'd have to screw it up pretty bad to have to screw with the turbo to get the hose on.
Title: Re: Dutt neck - worth it?
Post by: tb3 on April 26 2014, 09:33:21 PM
Remember the guy awhile back that said screw it and removed his intercooler, put a U pipe on it, put the ally to it, and had very good results?
makes me wonder how many running alky would accomplish their goals and would'a saved the $$$ by not bothering with a IC :chin:
Title: Re: Dutt neck - worth it?
Post by: tb3 on April 26 2014, 09:39:59 PM
Didn't know the tta ic's where same as gnx's!.
Learn something new everyday!
thanks Steve! :cheers:
Title: Re: Dutt neck - worth it?
Post by: motorhead on April 27 2014, 11:36:45 AM
Remember the guy awhile back that said screw it and removed his intercooler, put a U pipe on it, put the ally to it, and had very good results?
makes me wonder how many running alky would accomplish their goals and would'a saved the $$$ by not bothering with a IC :chin:

Lots of folks are running un-intercooled with E85 with great success... an intercooler is a bit of a band-aid/crutch when it is difficult to maintain a favourable air charge density.
Title: Dutt neck - worth it?
Post by: 87we4jk on April 27 2014, 07:01:27 PM
I've got a barely used core that I got dutt necked last summer and hope to have it in by the end of May. I am going to record a few runs before I make the swap. I'm running stock boost levels right now on 93 oct.. Will keep you posted


Sent from my iPad using Tapatalk
Title: Re: Dutt neck - worth it?
Post by: Steve Wood on April 27 2014, 07:38:32 PM
Doubt it makes any difference that cannot be attributed to the boost increase related to the better flow

Steve

Title: Re: Dutt neck - worth it?
Post by: phil_long on April 28 2014, 09:34:34 AM
Im so ridiculous, as I'm sitting over here hoping someone try out that ebay kit!!! :rock:  I really want to know how it works, and I've invested so much into my car over the last year, I can't take anymore chances.  Lol. I won't buy another intercooler anyway until I get a turbo(leaky leaky oil).  :hmm
Title: Re: Dutt neck - worth it?
Post by: TURBOPOWERED68 on April 29 2014, 12:51:35 AM
Im so ridiculous, as I'm sitting over here hoping someone try out that ebay kit!!! :rock:  I really want to know how it works, and I've invested so much into my car over the last year, I can't take anymore chances.  Lol. I won't buy another intercooler anyway until I get a turbo(leaky leaky oil).  :hmm

i just put and Ebay junk on my car, ill let you know how it goes.
BTW i am also installing a Dutt-necked IC onto my Regal.
Title: Re: Dutt neck - worth it?
Post by: phil_long on April 30 2014, 08:08:15 AM
What ebay piece did you put on there? And yes please, keep me informed.
Title: Re: Dutt neck - worth it?
Post by: TURBOPOWERED68 on April 30 2014, 10:14:03 PM
i got one close to this but with 3" in/out lets

http://www.ebay.com/itm/CXRacing-Bar-Plate-Intercooler-Turbo-1-Side-24-X11-X3-2-5-Inlet-Outlet-/140629768087?pt=Motors_Car_Truck_Parts_Accessories&vxp=mtr&hash=item20be2ff797 (http://www.ebay.com/itm/CXRacing-Bar-Plate-Intercooler-Turbo-1-Side-24-X11-X3-2-5-Inlet-Outlet-/140629768087?pt=Motors_Car_Truck_Parts_Accessories&vxp=mtr&hash=item20be2ff797)
Title: Re: Dutt neck - worth it?
Post by: deathraider6996 on April 30 2014, 10:58:56 PM
Out of curiosity, for that price, why didn't you go with a rjc?

Sent while curing depression with boost.

Title: Re: Dutt neck - worth it?
Post by: phil_long on May 01 2014, 09:22:11 AM
Yeah thats pretty steep in price!!!!
Title: Re: Dutt neck - worth it?
Post by: SuperSix on May 01 2014, 10:20:31 AM
I thought you were talking about a cheap mid ~$100 unit.  :O
Title: Re: Dutt neck - worth it?
Post by: phil_long on May 01 2014, 10:51:28 AM
As did I
Title: Re: Dutt neck - worth it?
Post by: deathraider6996 on May 01 2014, 11:51:09 AM
Same here!

Sent while curing depression with boost.

Title: Re: Dutt neck - worth it?
Post by: earlbrown on May 01 2014, 02:21:50 PM
the seller is out of them.  They guys that sell china stuff jack the price way up when they're waiting on a new container.  If you look at the sales history you can see they sold for $158
Title: Re: Dutt neck - worth it?
Post by: TexasT on May 01 2014, 03:08:23 PM
Pix of this "$158" intercooler? Comes with piping and such?
Title: Re: Dutt neck - worth it?
Post by: TURBOPOWERED68 on May 02 2014, 09:35:45 PM
NO NO i didn't look at the price.
the one i got was about $125.00 shipped
ID NEVER buy something that expensive
Title: Dutt neck - worth it?
Post by: TURBOPOWERED68 on May 02 2014, 09:50:50 PM
Pix of this "$158" intercooler? Comes with piping and such?

http://turbobuick.com/forums/threads/1968-chevelle-with-87-gn-engine.197799/page-19#post-3325534 (http://turbobuick.com/forums/threads/1968-chevelle-with-87-gn-engine.197799/page-19#post-3325534)
Title: Re: Dutt neck - worth it?
Post by: phil_long on May 05 2014, 09:25:35 AM
Ok cool.  Still subscribed and awaiting details. 
Title: Re: Dutt neck - worth it?
Post by: TWIN86GNS on May 18 2014, 11:31:04 AM
Anything you can do to help the flow will be beneficial and be worth your time and effort.  In the above link to the intercooler report I believe they didn't particularly like the Eastern Front Mount.  My Dad bought one of those intercoolers (and it is still on the car) back in early 1995 and it REALLY woke the car up.  The previous best mph was 114 and change and with the same combo, but with the new intercooler the car ran a couple passes of 120 mph.  That to me says about 60 hp and the Eastern FMIC is a small intercooler by todays standards. 

I bought a used Eastern FMIC for my car MANY years ago and it is still sitting on the bench waiting for some other upgrades before it is installed and I expect it to work well for me as well.

Title: Re: Dutt neck - worth it?
Post by: TWIN86GNS on May 18 2014, 11:33:10 AM
Just so I am clear, I am not advocating for people to run an Eastern FMIC, just passing along my experience with a "small" FM and how it really helped our car.  I am sure any new IC (FMIC or SLIC) will do the same for you and you will be happy.
Title: Re: Dutt neck - worth it?
Post by: SuperSix on May 19 2014, 11:13:30 AM
Let me know if you want to sell it. :D
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