What is the GRM way to driving a sweet sounding V-12 car?

Rocambolesque said:

It's funny this thread popped up, I was also wondering how to get cheap V12 power on a relative budget.

I've seen a couple of videos showing stock V12 XJS accelerating and they don't seem really fast... of course that's stock and this is GRM...

Let's say one gets a 5.3 HE Jaguar, puts a T5 behind it using one of the available bellhousings, re-gears to something like 3.73, makes a custom exhaust and makes it run on a standalone... Does that turn a lazy engine into something more entertaining? Is the 6.0 the way to go? 

It’s still a very heavy car. 4656 pounds!  The post 1993’s are even heavier. 

A gutted race car weighs under 3000 pounds though even with a roll cage.  And with intense focus 2700 pounds can be achieved and 2300 pounds has been done.  

But yes those changes livens it up a lot.  The 6.0 will only give you about 20-25 more horsepower. Plus most of them use a sintered iron crank,  not the forging of the 5.3 ( and that forging is a real work of art    EN 40 steel, really hardened. “ due to extreme hardness of crankshaft material regrinding is not possible on normal grinding equipment”  the crank alone weighs 78.8 pounds  

3 inch main bearings ( 4 bolt )  rod bearings are 2.300 

They aren’t kidding either. I’ve pulled crankshafts that were run without oil for miles and with a light buffing with some ultra fine emery paper were  still within new specifications.    The bearings though were almost dust.  

Stock is roughly 300 horsepower when Corvette 350 was 160 horsepower.  

They raced making around 450 horsepower on 4 SU carbs and won the SCCA runoff’s in 1975 against the Best Corvettes Fords etc in the country. 

In Trans Am against the best Ford Chevy BMW Porsche in the country won the manufacturers championship in 1978 with a XJS making 660 horsepower  in spite of weighing 200 pounds more than a Corvette. 

In IMSA  Jaguar XJS  In 1981. won the most races but lost the championship to Corvette because there were so many Corvettes racing. 

Over in Europe group A which required stock intake and  stock cast iron exhaust  stock virtually everything. the XJS  was regularly was much faster than the BMW 3.5 CSL  but an underfunded team lost due to  trivial issues such as failed windshield wipers, broken hood pin tires  punctured etc. but they never the less won in 1984. 

That engine went on to win LeMans  2 more times  making 640-670 horsepower on French Pump grade gas. 

In reply to frenchyd :

You sure know a lot about those engines/cars! I read a lot of your replies in other Jaguar threads and I understood that the engines were very stout. I like that. 

Three years ago I went to see an XJS for sale. I think it was a 85 or 86. Wasn't perfect nor finished, but mostly straight and rust free (for Quebec...).  The gentleman selling it said it hadn't started in 3 years (maybe it would've ran with distributor oil...). I wanted to buy it to put some sort of turbo LS in it... I ended up not buying it because I didn't have the space. Today I wish I had bought it, but stayed V12. Seems like there were many many old Jaguars for under 2000$ here up until last year or so. Now people want 10k+ for an XJS...

In reply to Rocambolesque :

Yes! The prices have increased a lot and are expected to go even higher.  

It’s not a car for a flipper though.  Any yahoo with a good line of gab and  a few wrenches can drain your bank account.  

Being a bottom feeder I find cars taken apart ( with nothing really wrong with them ) or a Chevy sitting in it. Still not running or sorted  properly. 

I play dirty though, I’ll offer a few bucks for the engine and transmission.  Months or years go by and the offer is accepted.  Then I wait for my offer for the rest of the car to be accepted.  

I’m getting old though.  I haven’t Evan returned some calls lately.   I’ve probably bought my last one.  

NickD said:

Cotton has owned a couple of cheap twin-turbo V12 Mercs, and it seems like if you're willing to do the work and know what you can and can't live without, they aren't too spendy. Not sure if a twin-turbo V12 makes the sounds you are looking for, but I bet the thrust would overcome the sound deficit.

A Jaguar V12 on a couple of junkyard turbos from Saab’s  isn’t melodious but sounds serious.   I built it to race in then Chump car now Champ car. But was told even though I could document what little I’d spent  it wouldn’t be allowed. 

Now I understand it would but there is no way to be competitive with its lousy fuel mileage. 5-6 mpg compared to 20+. ?  A fuel stop is a mandatory 5 minutes.  That’s at least 3 to 1 stops. More likely 4. 

On top of that you would have to turn stupidly fast laps just to stay in the hunt.  Passing a lot of people who just don’t have enough experience and wouldn’t  be expecting you.  

bruceman said:

I look at Jaguar XJS and appreciate the days when they were raced by Tom Walkinshaw . I recall the glorious sounds of the Group C Jags at Spa back in the 1980's. 

I would like an occasional driver car with glorious V-12 sound. How is that done in a grassroots way for $5-10K?

Engine Swap something with a V-12?

Or purchase older BMW, Mercedes, or Jaguar and put headers on etc?

 

The sound of a V12 really started with the ripping silk sound of a 3 liter Ferrari racing down the Mulsane straight at LeMans. The big Jag six cylinder booming right along or even passing the Ferrari  didn’t phase anyone. That V12 screaming  left an impression everyone talked about.  (Even Sir William Lyons) he too wanted one!  But not a little 3 liter.  Something big, 4 no, 5 liters maybe more! 

Still A Jaguar  doesn’t have that ripping silk scream at 8000 rpm though. No V12 does once it gets over 5 liters. but at least it doesn’t sound like a V8 

You have to run the exhaust pipes out the back to really hear a V12.   Dumped on the side you can only hear 6 cylinders  the other side is muffled.  

If you want loud use smaller pipes  It will cost you power but make noise.  Bigger diameter pipes give you more peak power but produce holes in the power curve where the  resonance baffles the exhaust ports and costs power at that particular RPM. 

For real sound you have to treat it like a musical instrument. Start small and go into a megaphone.  

My Black Jack spl. Had that. Headers into a bigger collector and ended with a pair of megaphones. Only 3.8 liters making barely 300 horsepower but it drowned every other car on the track. No V8 could make as loud a sound.  You could follow the car anyplace on the 4 mile long track at Elkart  lake just by the sound.  

$3500 xjs https://houston.craigslist.org/cto/d/houston-1990-jaguar-xjs-61k-miles/6902963785.html 

In reply to Strizzo :

If that were a 6.0 liter car it would be priced about right. A 5.3 it’s, even in today’s heated markets,  at least $2000 over. 

If you want multi-cylinder exhaust note, you could always try a V10. BMWs that have that engine are now becoming reasonably priced.

For a comparison of V12, V10 and V8 sounds, see  https://www.youtube.com/watch?v=Rb7PnkTB9Ik&feature=youtu.be

PS - I always used to taunt a friend who owned a Gallardo that 'real' Lamborghinis had 12 cylinders rather than 10 (which he had, while I had a vintage model with 12) but the sound of the cars wasn't all that far apart.

This seems like a good V12 option.

In reply to ¯\_(ツ)_/¯ :

Oil leak?  Could be a simple issue  or a major issue. 

I’ve tightened up a banjo bolt and stopped a”major leak” and found a engine that had been driven without oil that needed a complete rebuild.  

Miles are low and based on my experience,  probably correct.  However this is not a car for a flipper. Those without knowledge  frequently become victims of unscrupulous mechanics. Paying for things not really needed or can be fixed easily/cheaply  if you know How.  

All 80’s - 90’s luxury cars  are complex and not something that can be turned over to a neighborhood mechanic.  Heck in many cases not even to a dealer or specialist. 

wspohn said:

If you want multi-cylinder exhaust note, you could always try a V10. BMWs that have that engine are now becoming reasonably priced.

For a comparison of V12, V10 and V8 sounds, see  https://www.youtube.com/watch?v=Rb7PnkTB9Ik&feature=youtu.be

 

PS - I always used to taunt a friend who owned a Gallardo that 'real' Lamborghinis had 12 cylinders rather than 10 (which he had, while I had a vintage model with 12) but the sound of the cars wasn't all that far apart.

You’re right, isn’t the 10 cylinder out of an Audi? 

frenchyd said:

wspohn said:

If you want multi-cylinder exhaust note, you could always try a V10. BMWs that have that engine are now becoming reasonably priced.

For a comparison of V12, V10 and V8 sounds, see  https://www.youtube.com/watch?v=Rb7PnkTB9Ik&feature=youtu.be

 

PS - I always used to taunt a friend who owned a Gallardo that 'real' Lamborghinis had 12 cylinders rather than 10 (which he had, while I had a vintage model with 12) but the sound of the cars wasn't all that far apart.

You’re right, isn’t the 10 cylinder out of an Audi? 

 

The Gallardo's original 5.0L engine was not related related to the twin-turbo V10 out of the Audi RS6 and the N/A V10 from the R8, but the later 5.2L V10 in the Gallardo LP560 was derived from the R8 engine, but with changes.

In reply to NickD :

Still made by Audi though? 

You can take two v6 and connect them together to get a v12.  It just weighs more than a single-crankshaft v12.  Is weight an issue?   Must not be if you want a v12!

Only like a billion v6's available.

I mean, this would be my method.

It looks well sorted, the drivetrain actually has a decent rep for reliability, it's as cheap a car as I'd trust, miles aren't bad, and the owner appears to care for it. Buy it, get the maintenance where you want it, drive it. 

https://neworleans.craigslist.org/cto/d/metairie-mercedes-benz-sl-600/6906409528.html

In reply to Mike :

That's nice!

nimblemotorsports said:

You can take two v6 and connect them together to get a v12.  It just weighs more than a single-crankshaft v12.  Is weight an issue?   Must not be if you want a v12!

Only like a billion v6's available.

Most V6’s are 90 degrees not the 60 degrees that make the sweet sound.  Second few V6’s are all aluminum and none to my knowledge are as well constructed. ( 3 inch mains 2.30 rods. 4 bolt mains, long studs reaching almost from the crank webs ) 

Now I'm just trying to think of what v6s would sound good turned into a v12. Alfa anything is probably cheating.


Making horrible sounding ones would be easier, smash two 3.9s from 1st gen dakotas together so you have an almost 8 liter v12 that makes like 200 hp if you're lucky and hits redline at 4800 rpm. 

In reply to Grizz : a Jag, V12 can be bought for under a grand. A BMW. V12 more, $1500? Benz ? Another $500?  

Mashing together 2  V6’s ?   And boy would it be long.  Pulleys,water pump,  harmonic balancer, timing chain, then 6 cylinders,  end of block, end of crank, some kind of coupler,  pulley’s, 2nd water pump,  2nd timing chain, another block, 6 cylinders, end of block, flywheel. 

Jaguar is something like 31 inches long and can be easily taken out to 7 & 1/2 + liters without a new  crankshaft or block.   Stock a 5.3 has nearly 300 hp  but a pair of camshafts, compression and tune and you’re at 700 horsepower  

frenchyd said:

 Stock a 5.3 has nearly 300 hp  but a pair of camshafts, compression and tune and you’re at 700 horsepower  

Can't see it, at least not  without boost or nitrous entering the equation. I love old Jags and have had a bunch, although only one V12, and the idea of a 700hp XJS sounds like a lot of fun.

Please provide specifics:

How much compression?

How much lift/duration on the cams and who makes them?

How to tune it? Aftermarket ECM or tweaking the factory one? Will the stock injectors support 700hp?

What about the exhaust? Stock manifolds good for 700hp?

This thread just makes me want to toss a latest model Jag v12 in a 32 high boy frame with mega squirt and see what I can manage. I figure the Brits have hot cams for them figured out. 

Don't mean to break up the jaguar v12 redundancy that plagues every v12 thread but...

I got a 95 v12 Mercedes sedan for free. Once this divorce is over I'm going to MS this bitch and run straight pipes. YOLO! The Mercedes m120 is my favorite v12 and came from the factory putting down serious power. Zonda used them for a reason. 

Racingsnake said:

frenchyd said:

 Stock a 5.3 has nearly 300 hp  but a pair of camshafts, compression and tune and you’re at 700 horsepower  

Can't see it, at least not  without boost or nitrous entering the equation. I love old Jags and have had a bunch, although only one V12, and the idea of a 700hp XJS sounds like a lot of fun.

Please provide specifics:

How much compression?

How much lift/duration on the cams and who makes them?

How to tune it? Aftermarket ECM or tweaking the factory one? Will the stock injectors support 700hp?

What about the exhaust? Stock manifolds good for 700hp?

He left out two turbos. 

In reply to yupididit :

If you are serious about 700 horsepower you already know how.  30 years ago they were making that sort of power and running 24 hour races.  But you don’t do it on a GRM budget. 

Turbo’s make it a whole lot easier.  I made a whisker short of 500 horsepower on the $500 budget Chump car  ( now Champ car )  had. Today I could solidly exceed that 500 hp number ( but never win a race). 

yupididit said

He left out two turbos. 

Sounds about right