A couple of the projects we done for Astons that have been very successful & popular are headers for the V8 & V12 cars. We can go from this:




To this:



Lots of power on tap! I'm looking at some of the schematics & parts systems for the 5.0L Jag Engines, and it looks like they come with a cast 'log' manifold. One of the advantages of putting a tubular manifold on a supercharged engine is that, although better exhaust gas scavenging can have the effect of dropping the boost pressure a little bit, they often make more power at lower boost. Aside from increased power there's an added benefit of less stress on the engine. It doesn't look like there's anything available for these engines at present. Is anybody interested in a product like this?

Hopefully we can go from this:



To Something like this:





Please chime in with your thoughts. If I'm barking up the wrong tree, let me know. If you think this would be something of interest, or if you have specific things you would want to see/not want to see in a product let me know too!

Thanks Guys!

 

For some reason, the 'before' image for the Jag is missing.

I'm afraid my opinion will be somewhat moot, since I'm on the wrong side of the Atlantic and shipping big lumps of stainless around is kinda expensive. However, for what it's worth, if you had independent dyno proof of some significant gains, it would be an interesting prospect. Would depend on price, of course - how much does that Aston snake bag go for?

 

count me in. Ive mainly just been searching for some test pipes (catalyst elimination) but if I could get headers or even a one peice set up (headers & test pipes) then I could go with your catback or even any cat back system on the market and have great performance and great sound. Would the headers come with new hardware? Like new studs/bolts and gaskets? Also, for the catalyst elimination could you guys build something like the CEL eliminators on bigdaddiesgarage?

Im trying to get the most hp out of my XKR as possible. I got word from a tuner that the are very close to cracking the TCM tune to allow the car not to restrict the power to the tranny...Id love to have a 700hp XKR!!

 

Not sure why the before image isn't showing up, shows up for me. It is basically a 'log' manifold, with no primaries at all.

You're not on the wrong side of the Atlantic at all. I live in Canada, and we sell primarily to North America, shipping a set of manifolds is less than $100 to most N.A. destinations, but our company is actually based in Dorset and that's where we make everything.

So you're much closer than you think. £15 delivery!!!

 

Sweet, Im in Iowa. Road trip to Canada this summer! Lol.

 

Is this a direct bolt on and will it work with aftermarket cats?

 

If we go ahead with this, it will be a direct bolt on (as in, no cutting or welding) but based on the OEM parts schematic I would say it will have to be a replacement for both the OEM Manifolds + Downpipes/Cats all together. The reason for that is that the OEM manifold is literally just a log with a section just a couple of inches long at the end before it hits a flange. There would be no way to build a proper merge collector or any sort of primary assembly into that small a space.

However, if you replaced the header and the cats together, there is more room to produce something decent. It could then be supplied either totally cat-less, or with a highflow Motorsport Cat integrated.

 

Sorry, I missed this one yesterday. The V8 Vantage Headers are $2995 in 304 grade stainless, don't ask if you want them in Inconel 625! We also sell high flow catalysts for those cars for $1895 (20gsm high quality loadings.)

Hard to say for sure, but depending upon the final configuration, I would say that all things being equal, a cat-less header with O2 sensor locations would be around the same as the Aston units, ones with integrated high flow cats probably $35-3600.

 

So, about £2.1k - plus VAT, about £2.6k. I'd want to see proof of some significant gains for that outlay. I like the idea, because it's (relatively) easily reversible - having a collector's edition model, I don't want to affect its value with mods that are hard to undo (like a pulley swap).

 

Somewhere in that range, yes. Hard to know 100% until we've really gotten stuck into the project but I think that's a reasonable estimate.

Me too!

I get that - reversibility is always a plus. One of the downsides with the pullies is that you can't even order a replacement OEM pulley. To the best of my knowledge you can only order the whole charger assembly.

 

I want some headers....and extra bungs welded in for dual bank wideband sensors. No cats. And the rest of they system just loud enough not to be annoying when the cruise control is on. Otherwise, let it ROAR!

 

I am very interested in speaking about some headers for my 2012 xkr!! I’m in Winnipeg.

how do we get the ball rolling on this??

 

Hi @blueballzz. You might want to take some time and introduce yourself in the intro page and fill out your profile. Also, this sight has a feature called infinite scroll which you may have stumbled upon. The post you replied to is from 2014. Welcome and best of luck

 

How long are you willing to wait, and how much $$$$$ are you willing to spend? Why headers, and what is your ultimate goal?

Does your XKR have the Performance Active Exhaust (X-pipe)? Have you already done the pulleys and custom 600+HP tune? If not, that's money better spent than on headers.

 

I actually spoke with Stuart from velocity about this , the project was canned as it didn't make the expected power on the supercharged 5l the test vehicle was a f type.

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Why am I not surprised?

 

If Just Headers were applied with no further tune, I'd not expect any gains at all.
To truly test any benefits with headers, first a tune would need to be loaded to the stock configuration.
THEN the headers added and a similar tune uploaded but optimized for the headers.
That's the only way to find if headers would help at all. I'd be really surprised if there wasn't any gain with headers, headers are just..... better.

 

We tested the headers pretty thoroughly, including stock and tuning files and there was little to no benefit. Some small amount of torque (around 15ft/lbs, within a pretty narrow power band of just over 1000RPM.) However not enough to justify the cost of the project. We also had concerns about installation problems. It's extremely difficult to keep a TIG welded stainless header flange perfectly flat. The heads are aluminum so the torque spec on the header bolts is 10ft/lbs. Given the EXTREMELY difficult access on the FType, and all the other smaller body vehicles (RR is a little easier) the likelihood of stripped threads etc. would be very high.

So overall, the cost/benefit is just not there. Particularly on an vehicle where more power & torque is just readily available through tuning & pulley options.

 

This guy picked up about 70 HP and 50 TQ from a full exhaust with headers and an accompanying tune. To zero in on the contribution of the headers, how much power do catbacks with tunes make on those cars?

https://www.jaguarforums.com/forum/x...rs-too-200795/

 

It's difficult to evaluate external dyno results without seeing full datalogs & knowing background information. However... the baseline is 490WHP. With those mods I would essentially expect to see stock numbers. The pulley won't make any significant difference unless a tune is applied because all the excess boost created is vented by the bypass valve once it hits commanded peak boost. To add a tune to that, we would expect to see gains of 70BHP or so at the crank, depending on the upper supercharger size. Given the drivetrain losses I would infer for their baseline, that would be 62-62WHP.

They are showing a gain of 70WHP from adding headers, full exhaust, upper pulley + tune.