GHL Headers Suitability

[Pork Chops]

Hello.

I've turbocharged a 3.2 Carrera the details of which can be found here

Turbo 3.2 Carrera Ignition Upgrade Pathway

but it's basically an unopened US spec 3.2C, Garrett 3582R 0.82 AR, VEMS ECU, running 10lb of boost. Exhaust is standard heat exchangers with a J pipe. Makes a laggy 400fwhp.

I've got the opportunity to buy some GHL headers with heat, per the attached image.

Primaries are 1 5/8" and because of the shape of the collector and the heat exchangers I'm guessing they are 'shorties' and not 'tuned length'.

I will be adding an ethanol flex fuel set up as well as the headers which will allow the ignition timing and boost to be more aggressive due to its excellent knock resistance.

I'd like to see a 100fwhp increase taking it to 500 but importantly also reduce lag / make the engine more responsive.

So given the cost and effort of fitting these headers my question is are they going to offer a good enough increase in performance to be worth it and also are they suitable for my goals?

Cheers.

[Alan L]

I had some of those on my car. I cut the heat boxes off (track car only). That exposed the pipe junctions - which were considered inferior to others.
There are better headers you could buy I suspect. Of course price will be the issue. But Brian (rarelyL8) makes excellent headers and I think has heat option available also.
I suspect your gaining another 100Hp is probably a bit optimistic. My 2c.
Alan

[Pork Chops]

Originally Posted by Alan L

I had some of those on my car. I cut the heat boxes off (track car only). That exposed the pipe junctions - which were considered inferior to others.
There are better headers you could buy I suspect. Of course price will be the issue. But Brian (rarelyL8) makes excellent headers and I think has heat option available also.
I suspect your gaining another 100Hp is probably a bit optimistic. My 2c.
Alan

Thanks Alan. Re power i guess we'll see but E85 is a game changer. In the end it will be what it is, and frankly even if it offered a nice bump in torque and made the turbo spool up faster I'm sure I'd be happy with that. I would ideally love to have a set of Brian's headers but they are a relatively expensive option with the GHL units costing $1k AUD and they're on my garage floor already!

[Alan L]

I hear Ya.
But I bit the bullet in the end and ordered some of Brian's. No regrets.
And I have some GHL headers on my garage floor too :-)
All the best.
Alan

[Rodsrsr]

I doubt you'll pick up 100 hp but either way your gearbox will be the limiting factor. (unless you have a G50)

[crb07]

I cracked my GHL’s and gave them away to someone who wanted to try and repair them.

Fabspeed are nice. Wish I could find another set. Pricey new.

[Pork Chops]

Originally Posted by Rodsrsr

I doubt you'll pick up 100 hp but either way your gearbox will be the limiting factor. (unless you have a G50)

It’s a G50 or I wouldn’t have bothered. As for the hp are you familiar with the tuning possibilities of ethanol? But let’s try and stay on topic with my question being about the headers.

[Pork Chops]

Originally Posted by crb07

I cracked my GHL’s and gave them away to someone who wanted to try and repair them.

Fabspeed are nice. Wish I could find another set. Pricey new.

Where did they crack out of interest?

[Alan L]

I think I had to have mine repaired also. It is a while back, but when I am next at them (few days time), I will have a look for some repair marks.
Alan

[Pork Chops]

Originally Posted by Alan L

I think I had to have mine repaired also. It is a while back, but when I am next at them (few days time), I will have a look for some repair marks.
Alan

Here's a question for you. Were you able to tell the difference between the GHLs and Brian's? That kind of assumes all other things were equal including the tune. Worth asking...

[Alan L]

If you are asking for a seat of the pants dyno evaluation, it would be hard to say. if you have a look at the specs of my car, there are many changes and the headers were changed during some of the many upgrades (10-15yrs ago). It was quite some time ago, and I doubt it was just a swap of headers.
But one manufacturer of headers that I was looking at was quite critical of the GHL design.
Regards
Alan

[spuggy]

As far as GHLs go, I got a set of Fabspeeds - and ended up leaving the GHLs on the car, because they looked better made to me. Mine never cracked, and I never had boost creep with them - momentary overshoot by 2 PSI or so, drop back to wastegate spring within a couple of tenths of a second. Wastegate takeoff on the Fabspeeds didn't look like an improvement to me - the opposite, if anything, IIRC.

GHLs were also usually made to fit 930s, but you have a 3.2 - aren't these ports at least a little larger than 930 ports (which I seem to recall are 38mm? That 1-5/8" you quote - is that outside or inside diameter? I looked up the spec I ordered from Brian, and got

Tuned 930 headers, 1.63"/42mm primaries with gasket protectors, T3 turbo flange, single waste gate.

So that's ~1-5/8" ID - to suit the "spare" 930 heads I had ported to 3.2 specs and machined for thick-flange style headers with gasket protectors/stubs.

Originally Posted by Pork Chops

Were you able to tell the difference between the GHLs and Brian's? That kind of assumes all other things were equal including the tune. Worth asking...

Trouble with this question, as you seem to appreciate, is that relatively few people are going to change only one thing at a time... Alan L may be one of the few folks that can provide an answer to this.

Brian very likely could too - but I suspect he's going to be inclined to hold off from commenting because he doesn't want to appear to be hawking his goods here.

(Which, actually, when you've got Brian's headers on the bench, just sell themselves, IMO. They're extremely high quality and worth every penny. Best welding I've ever seen, no question - hard to believe a human did it. And custom-made to your specific requirements.)

Most others are likely going to do other things "while we're in there". And especially so because it's pretty well-understood that certain changes complement each other or are required in concert with the other changes to make the most of them.

FWIW, I found a big improvement in spool/response when I went to GHLs from factory RoW headers - however, added a Kokelyn and a K27/HF at the same time. Another big bump in response came from dialing in extra advance off-boost (and handling boost retard with the J&S Safeguard).

When I went from GHLs to Brian's headers, I found that the end-result was a massive improvement. However, I also went with Pauter rods, 3.2 manifold, flame-ringed/ported 930 heads, and twin-plugged with COP, as well as MoTec with sequential injection/boost control. Response is insane in comparison to CIS with the pancake manifold.. It buzzes along sounding angry at cruise and just wants to rev - manifold vacuum vanishes pretty much instantly when you get in more throttle, so boost transition is right there...

But clearly, none of these are exactly useful as an apples-to-apples comparison because too much else was changed as well...

[spuggy]

Originally Posted by Alan L

there are many changes and the headers were changed during some of the many upgrades (10-15yrs ago). It was quite some time ago, and I doubt it was just a swap of headers.

LOL. So much for me thinking you'd have tried this Alan

Originally Posted by Alan L

But one manufacturer of headers that I was looking at was quite critical of the GHL design.

Someone I have conversations with (who actually worked on 935s in the day), pointed out that the factory used primaries that were as short as possible.

Dunno, above my paygrade/knowledge. I get the impression that to really get the most out of equal-length primaries, you probably go with twin-scroll or even divided volute as well. But then you're balancing all kinds of things that are unquantifiable - at least by me...

I can't even get a feel for how much equal-length tuned primaries help with response on my current motor - because lower reciprocating mass (J&E pistons, Pauter rods) and reduced airflow resistance (MAP sensor, no barn-door CIS airflow or Motronic AFM in the way) almost certainly both play a part. As well as more advance in the map thanks to EFI, while twin-plugged.

Some have reported boost creep with GHLs as well as other aftermarket 930 headers. I never saw it with mine, even with a factory muffler (more backpressure than open exhaust). However, I have always ran an open dump pipe - probably also a factor.

I found the guy who owned GHL (Jeff? I think?) very helpful on the phone when I got a previously-owned set and called needing accessories/oil lines etc. long time ago. Shipped me a drip tank same day - and provided factory part #'s off the top of his head for early-style oil lines...

Gotta say though - GHLs were made for a long time. I get the impression from some experiences others had that quality, perhaps materials and maybe even design didn't necessarily stay the same for the whole run. But I liked the set I had...

[lite75]

When I ran that same turbo with the .82 hot housing I couldn't control the boost using one wastegate, spool up was incredibly fast. That was with Fabspeed headers.

[Pork Chops]

Originally Posted by spuggy

GHLs were also usually made to fit 930s, but you have a 3.2 - aren't these ports at least a little larger than 930 ports (which I seem to recall are 38mm? That 1-5/8" you quote - is that outside or inside diameter? I looked up the spec I ordered from Brian, and got

So that's ~1-5/8" ID - to suit the "spare" 930 heads I had ported to 3.2 specs and machined for thick-flange style headers with gasket protectors/stubs.

(Which, actually, when you've got Brian's headers on the bench, just sell themselves, IMO. They're extremely high quality and worth every penny. Best welding I've ever seen, no question - hard to believe a human did it. And custom-made to your specific requirements.)

OK so the OD on the GHL headers is 1 5/8". Good point re 930 vs 3.2C heads. The GDL headers have the thick flanges (what I want) and I've read on other threads that factory 3.2 heat exchangers are 1 5/8" and therefore should fit. I would ideally love a set of custom headers from Brian but time and money both blow out with that option. Hence I'm asking if the effort of fitting the GHLs is worth it compared to stock 3.2 HEs. I will likely end up with Brian's product but just not right now.

Brian if you're lurking feel free to chime in. We've exchanged a few emails and I'm quite sure your contributions will be fact based.

[Alan L]

Here is a pic of what they look like without the heat boxes.
I have looked for a weld repair and cannot find one - altho it may be well disguised. I do recall getting some welding on them. One weld seam looks like it may have been re done partly.
Alan
Sorry - the pic won't allow me to post it. Need permission from the file administrator. WTF

[Alan L]

[Pork Chops]

Originally Posted by Alan L

You beat the system Alan. Well done! Nice to see them naked. I guess these are shorty or log style. Certainly not tuned length so quality aside the question remains what improvements might be associated with fitting these over the factory 3.2C heat exchangers.

[RarlyL8]

Anything is better than the OE 930 heat exchangers, and the J-pipe version is better than the Y-pipe (75-79 USA) version. Generic short tube headers offer performance by deleting excess tubing length and small ID restrictions. They are all pretty much the same with most being produced inexpensively overseas. Cracking is common. The basic short tube design offers a lot of opportunity for improvement, which is what we did with our tuned headers. The collector on most is horrific. All 3 uneven primaries dump into a common chamber. Any advantage in velocity gained by having a short path to the turbo is pretty much shot right there. The single 90° elephant nose waste gate pipe encourages boost creep.



Tuning the primaries does many things; torque off-boost is increased and HP on boost is increased. Waste gating excess flow evenly off both banks and at smooth angles helps to control boost pressure regulation. Materials and welding are quality for a very long service life even with track use.
If on a budget then yes, the short tube headers will work. Our system takes things to the next level.

[spuggy]

Originally Posted by Alan L

Alan, are you sure those are GHLs? If so, d'you know what generation? I got no skin in it, but just curious; see, the headers I bought from a Pelican in (I looked - 2007 - sheesh. Thanks Mike!) - and was told were GHLs, looked quite different. They

(a) had a slip joint (which, on cold days, from the sound, was obviously open for a few seconds until it warmed up, expanded, went "sssspppbt" and stopped) &

(b) the collector angles/arrangement on mine looked different/better(?)

eg (from my 2013 For Sale post https://forums.pelicanparts.com/porsche-911-used-parts-sale-wanted/766571-3-3-930-upgrade-parts-kokelyn-ghls-abs-airbox.html: