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MARKUSA
MARKUSA New Reader
7/16/18 1:01 p.m.

In reply to frenchyd :

Just regular green antifreeze? or the orange?

MARKUSA
MARKUSA New Reader
7/16/18 1:34 p.m.

In reply to MARKUSA :

How much does adding turbos affect exhaust note on these engines?

frenchyd
frenchyd SuperDork
7/16/18 3:35 p.m.

In reply to MARKUSA :

The one I did I ran without mufflers at all. But I put a turn down just ahead of the rear axle on both sides. It beat the noise meters at the race track but it was plenty loud if you were really on it.  

I’d think it would be too loud for your wife without mufflers. 

frenchyd
frenchyd SuperDork
7/16/18 6:43 p.m.

In reply to MARKUSA : I’m sorry, it turns out it’s being sold by Robbie Frazier in the Jaguar XJS enthusiast group 

 

MARKUSA
MARKUSA New Reader
7/16/18 6:59 p.m.

In reply to frenchyd :

ok thanks.  Its along ways anyway.

frenchyd
frenchyd SuperDork
7/17/18 1:12 a.m.

In reply to MARKUSA :

I’m so tempted. I’ll bet a couple of hundred dollar bills would buy that. 3 would be my top offer because that would be twice what he’d get from the junkyard.   It’s only a little over 400 miles  one way. and another set of flatheads  with those nice seats is extremely tempting.  

There does not  appear to be any rust holes in the body that I can see although the paint is gone on the top of the car indicating it’s been out in the sun for decades. Neglected that long tells me rust would be blistering through the fenders by now. It’s not, they are nice. The body seems too nice to just scrap. 

 

I can’t tell because the speedometer needle is covering the first number on the odometer but I suspect it only has 43,370  miles on it.  You can see the bottom of the number and it’s not round.  

As nice as the interior appears, rust free fenders, I think low mileage. I’ll bet it was some guys retirement car that may really need very little in the way of mechanical repairs.  

But with my wedding less than a month away if I came home with that, I’m not sure I’d get out of the dog house in time to walk down the aisle. 

ps, I bought my 84 XJS for $500 and drove to California and back to get it. Although much of the reason for the trip was to spend time with my best friend from the Navy.  

MARKUSA
MARKUSA New Reader
7/17/18 7:35 p.m.

Congrats on your wedding!!

frenchyd
frenchyd SuperDork
8/17/18 10:33 a.m.

In reply to MARKUSA :

Wedding is over so now I get to play a little bit. I think I check on the guy in Joliet and see if he still has the Jag. 

Dirtydog
Dirtydog Dork
8/17/18 1:18 p.m.
frenchyd said:

In reply to MARKUSA :

Wedding is over so now I get to play a little bit. I think I check on the guy in Joliet and see if he still has the Jag. 

Congratulations.  Much health and happiness!!   Welcome to the "Oldyweds Club".   Time to play.

XJ13
XJ13
3/22/20 10:00 a.m.

You need one of these ... cheeky

The tera V12 ....

 

frenchyd
frenchyd PowerDork
3/22/20 4:50 p.m.

In reply to XJ13 :

While those are fantastic and very lust worthy, I'm certain the price is as well.  
 
I'm much more of a what's available at junkyard prices.  
  Over the years I've seen too many nice cars sell dirt cheap because the currant owner can't figure out how to get them running. 
Stuff like that isn't for the Flipper since you actually need to learn how to get it running in order to stand a chance of seeing a profit. If you really understand cars it's not magic. Or that hard of work.  Forget about having the shop do it. 
 

A hobbiest who isn't lazy can do it easily enough. There are U tube video's that can explain things well enough.  But it's too much work and expense to just stuff a Chevy in to ever come out on top.  It's been tried countless times.  

People ask silly prices for them and some fools pay those prices. Here is the real numbers if you want a Jaguar V12 
 Rusty Parts cars without a tittle are worth scrap iron prices. $150. 
Rusty  parts cars  with a tittle are worth maybe $50 more since now you can scrap it.  if you separate the aluminum. You'll make a little more but it will take more than 10 hours to do. 

Rust free bodies add a couple of hundred dollars and the tittle adds a couple hundred more.  So you could get $750- $1000 

Running cars even with issues add $1000 to those numbers  

1975-1980 cars in decent shape, drivers,  are worth North of $3500. With earlier (1975) cars commanding +$5000.  1981-1988 cars in driver shape with no issues.  Can command nearly the same price. Convertibles add a minimum of $2000 and special editions can command $10,000 over that. The best ones are the 6.0 convertibles. Good driver quality  6.0V12's start at $25,000 and have commanded prices  well over that at auctions 

frenchyd
frenchyd PowerDork
6/26/20 11:04 a.m.

In reply to frenchyd :

Update;  

I'm embarrassed  to find out how hard I've  made a simple thing. In the past when I wanted to improve the flow through the heads ( and gain the added power that offers )  I ordered Blank Chevy valves and had them ground  to fit.  Result was a valve that approached $50 each. 
Turns out I could have saved myself almost $40 each.  Rock auto sells new intake valves for the 4.2 for $11:00 each.   Order the valve seat for that as well and  Bob's your Uncle. 
     Careful now. Bigger valves require bigger ports  and doing a good job of that is 200+ hours of hand porting and testing. Plus there isn't a lot of room for error without hitting water.  I threw away 3 heads before I got  both heads and all the ports to flow equally. 
Plus it turns out there were two places that cast the heads.  One has thicker walls than the other. Thus more chance for a non fatal error. 
Yes you can probably get into the port and Weld it back up. But when I was doing that most engines I got were the early Flathead engines.  So  I'd  just grab another and be more careful the next time. 
Now the Flatheads are getting rare. They're even porting the dumb HE trying to get it working.  Giving up compression to get it flowing around the recessed valves. 
I did figure out how to port the engine in about 10 hours using  a vertices mill.  By taking a ball mill do a plunge cut into the port stopping just before it intersects  with the  part of the port coming from the intake manifold. The part of the port  from the  intake manifold is at a different  angle and elevation in all 12  ports but I measured  each one using a piece of brass  tube and two washers and  an angle finder. 

The result is a slightly smaller port than hand porting but it actually flows better. I wish I'd saved all that information. It would sure make  things easier. But I gave it all away with the V12 E type I sold. 
 

Don't bother with the exhaust port. It already flows  too much.  The formula for exhaust is 80% of intake  and  it's at 91% stock.  Port the intake  bigger and the formula gets  the exhaust near  perfect.  
Oh!  The tailpipe off the exhaust manifold is 2 inches. By going to 2 & 1/2  all the way back  there is a comfortable 30 extra horsepower waiting for you. 
 

Using stock sized intake and exhaust valves.   And cast Iron factory exhaust manifolds with stock intake required by group A regulations   TRW  made 450+ horsepower.  Group 44 made 460 horsepower using the Stock(ish)  carbs in their XKE 8 years earlier. 

frenchyd
frenchyd PowerDork
7/1/20 1:27 p.m.

In reply to frenchyd :

Power adders for the street. 
#1 the noise nozzle on both air cleaners hurts power but muffled intake sound.  In addition it picks up heat from the engine and off the radiator. 
If you remove those and replace them with 3 inch aluminum flexible dryer hose. You can gently shape them to pick up cool fresh air from in front of the radiator.  That's worth 30 horsepower. 
 
#2  the tailpipes from the exhaust manifolds on are 2" . If you increase them to 2 & 1/2" there is a solid 15 horsepower plus the exhaust note gets deeper. 
 

#3 eliminate the triple bypass mufflers. Use only the rear resonators. You will hear the exhaust but most don't find it objectionable. That's reportedly worth over 20 horsepower. 

AJ6 Engineering in England has the whole thing is stainless steel and it really looks nice. But by the time it gets here it's shocking what it will cost.  Local muffler shops should be able to do it much cheaper. 
 

Starting with 264 horsepower DIN. You could be at 329  horsepower.  
 

#4.  Depending on if you have access to really good premium you can advance the timing. Quick and dirty every  1 degrees of advance will get you 2 1/2 extra horsepower.( My race car I advance a total of 5degrees. )If you ever need to use less than that for fuel be sure to drive gently. Accelerate slowly.  

  • Since the 6.0 has 314 to start. The same changes will get you to 379 Horsepower. Plus about 2.1 horsepower per degree.  Lacking a PROM chip Im not sure how you will achieve that. 

     
frenchyd
frenchyd PowerDork
9/23/20 5:28 p.m.

In reply to frenchyd :

400+ Horsepower!  
Changing  the camshaft on a V8 is a complex job.  Usually you need to take the whole front end apart, maybe even drop the oil pan, then remove the top of the engine, remove the valve covers, pull the rocker arms, pushrods,  lifters,  then slide the camshaft put being careful the cam lobes don't gouge the cam bearings. 
Replacing  it is the reverse.   Many hours of work. 
on a Jaguar you remove the cam covers and there is the camshaft. Right on top.  They even make it easy in that in the tool kit is a cam gauge. Same one they've used since 1947.  Notch on top of the camshaft when both sides are touching and the crank is on top dead center the cam is aligned. 
To make sure you don't drop the timing chain they have a bracket in every engine to hold the tension on the chain. A 3/8ths fine thread nut screws on the bolt sticking out of the veneer adjuster. Then you remove the two bolts that hold each camshaft. All you do now is remove the bearing caps by unbolting a 7/16th nut on each side.  Send the camshaft in to your local cam grinder. The second most commonly used master lobe for a Ford Flathead  will get you a little over .405 lift and longer duration.  Isky calls it their XM3 ( still will idle at 650 rpm as smooth  as ever ). 
    That's good for 82 more horsepower. 
Yeh, you've got to adjust the shims and as long as you have a .012 feeler gauge  and 1 inch micrometer ( plus know how to add and subtract ) you're done in a few hours. The next time will be even faster. 
 

So now you're at 419 hp.   Not only that but where the stock cam laid down at 5500 these regrinds should get you well over the factory red line of 6500 

With the tiny 2.75 stroke that's a walk in the park. And the factory tested the engine up to 8300rpm before valve float began. 
 

But wait?  Could there be more?  I don't know much about EFI. But if the engine has been burning 91-92 octane and you feed it E85 with its 100 octane. It will need about 60% more fuel. Jaguar ( Lucas ) makes  injectors that do that.  For  your extra fuel you will get about 10% more power on the early 75-80 engines and 12% more power on the later HE 

 That's 460/470  horsepower. 
 

     Could there be more?  
 

To keep the HE  engine  with its 11.5-1 compression ratio from pinging on 91-92 octane  the factory retarded the timing from 41 degrees to 17 degrees.  
With E85 we have 100 octane. How much timing and how much more horsepower?  
A crude rule of thumb is 2&1/2 horsepower per degree.   So 4 degrees should get another 10 horsepower.  Think there is room for more?  Go all the way to say 23 or even 24 degrees?  For racing we put it on a chassis dyno and advance the timing until power stops increasing. How much to back off from that point depends on you.  Me? I look to where power increases flatten out and go one degree back from that.  That gives me enough reserve to relax. Being right on the edge means there are conditions where you'll be over the edge. If I've got 99.5% of power available with a small reserve my experience  tells me I'll be OK. 

frenchyd
frenchyd PowerDork
9/24/20 7:00 p.m.

What about us Luddites?  We start out 20 horsepower less than because we use carbs instead  of EFI. 
 

But wait. One of GRM's posters started out with a V12 with carbs. The intake manifold has a dog leg to pick up heat ( and get under the fenders of an XKE )  if you cut that off you pick up 30 horsepower on a chassis dyno.  
 

What about Weber's?  They are indeed wonderful eye candy. But they cost a fortune. Then you need a second fortune to buy all the parts needed to tune them. And  a 3rd fortune to do all the time required to adjust to the various weather conditions. 
Worse the set of Weber's  IDF's. ( IDA's are too tall ) on the shortest manifold with  the shortest possible air filter gives only 3/8ths of an inch clearance between the top and the hood. In other words poor power production. 
Group 44 did some very clever tricks to get a set to fit and work on their XJS 

frenchyd
frenchyd PowerDork
9/25/20 12:37 p.m.

In reply to frenchyd :

What if you want to go beyond that?  Where is there power to be had?  
Obviously the later 6.0 makes 56 horsepower more. Built in 1992 usually sold as a 1993 they continued through until 1997 but only 3 were made that year.  The engines are basically the same both Sedan and XJS 

They were batch made. About 3000 were made with the forged crankshaft made with Hardened EN 40 Steel  then they went to Sintered Iron for the final batch. Most 93&94's were forged the rest were the sintered iron. Plenty strong enough for mild modifications but serious power makers prefer the Forging. 
Starting about 1990  the factory also made improvements in crankshaft sealing and a bigger oil pump. 
   For those fascinated with technology the 93's  and later also had the most developed ECM. Instead of distributor they went to crank detection coil on plug ignition. Luckily for us Luddites all the parts are still there to reverse it and go back to distributor. 
      Go big or stay at home. 
The Jaguar crankshaft is a massive affair. 78.8 pounds of the finest steel forging. ( Chevy' V8's are around 25 pounds ) Then hardened so your normal crank grinder might not be able to do the following. 
The stock crankshaft has massive 2.3 rod journals.  
most common connecting rods are 2.1 or smaller. If you offset grind the crankshaft to that 2.1 size you can pick up a total of .400 stroke. Considering the loads on the crank you can even go to 2.00 or even the Honda size of 1.94 inches. NASCAR does it and those engines are required to run as much as 1100 miles  plus all the practice and qualifying assume over 2000 miles at  engine speeds well over 9000 rpm. Putting 4 times the force the Jaguar does. 
 But that's not all! 
Stock bore on both the  5.3 and the 6.0 is 90 mm about  3.543 it is possible to take the Jaguar out to 96 mm about 3.779 

How  expensive will that be?  Well I last paid $357 to offset grind and reharden my crankshaft a long time ago. But it shouldn't be wildly more expensive.  Then I carefully shopped places like Summit and Jegs etc. until I found Chevy connecting rods that with slight modifications would work. Again a quick glance has sets at around $400x2 =$800 
   Since I was using Chevy rods it made sense to use Chevy pistons.  A quick glance says the Kieth Black pistons for the 4.3 will be  workable.  The thickness at the top will allow the modifications required and still retain the shape to maximize power. They cost $183 a set but you need 2 sets ( gives you 4 spares) and 4 spare connecting rods too 
 Total?  Rods bearings rings pistons and machine work budget $2000 and you should be pretty close. 
with a 5.3 you're at 415cu in. With a 6.0  you're at  450 cu in 

frenchyd
frenchyd PowerDork
9/26/20 2:35 p.m.

In reply to frenchyd :

Once you've built up the bottom end. Attention needs to be paid to the top. 
The HE heads in both the 5.3 & 6.0 limits ultimate power to around 450 horsepower.
 So to capitalize on previous changes the earlier heads 1971-1980 so called flatheads are required.  Power levels approaching 800 horsepower have been produced using ported versions of those heads.  

Rob Beere sells oversized valves and the required oversized lifters to capitalize on the bigger British camshafts sold by Piper or Kent. You will also need to machine the cam carriers oversized to take the oversized lifters. I always machine mine slightly undersized and hone to finished clearance. 
At this level work on the intake is required. You can replace the stock butterfly's with butterfly's from a pair of 4.0 in line six cylinder engines  for additional capacity doing a modest amount of modifications. extrude hone the runners  and match to your ported inlets.  
For carbuarators again extrude honing is called for  and you might want to switch from the 175 Strombergs to the HD 8 SU carbs. 

yupididit
yupididit PowerDork
9/26/20 8:24 p.m.

Frenchy,

Whats the best way to install a 3 pedal assembly in my XJS?

Donebrokeit
Donebrokeit UltraDork
9/26/20 8:46 p.m.

Wouldn't a G.M  small block unit work?

Stampie (FS)
Stampie (FS) MegaDork
9/26/20 9:40 p.m.
frenchyd
frenchyd PowerDork
9/26/20 9:46 p.m.

In reply to Stampie (FS) :

The potential is there. Yes you can put NOS in anything and go faster. For just as long as the tank(s) hold out. 

frenchyd
frenchyd PowerDork
9/26/20 9:55 p.m.

In reply to yupididit :

One of my friends took a stock brake pedal assembly and modified it to take  a second pedal. 

You could chase ( on the phone) around British junkyards where most of the manual transmission(6 cylinder )  cars were sold. 

For a race car I'd just take out the stock pedal assembly to give me room  for an aftermarket pedal assembly. 

frenchyd
frenchyd PowerDork
9/26/20 9:57 p.m.
Donebrokeit said:

Wouldn't a G.M  small block unit work?

Sigh,  you are aware that most small blocks make a lot less power than a V12. Look up the difference between gross or Advertized horsepower and SAE net. 

wspohn
wspohn Dork
9/27/20 10:37 a.m.
frenchyd said:

In reply to Stampie (FS) :

The potential is there. Yes you can put NOS in anything and go faster. For just as long as the tank(s) hold out. 

Or for as long as the engine holds out.  I had a daft vintage racer friend who ran a Daimler SP250 (which I think supports the characterization of 'daft') and he added NOS to it. Of course it added a bunch of power but the next time he changed the head gaskets he commented that the piston crowns had 'gone all wavy".....

EvanB (Forum Supporter)
EvanB (Forum Supporter) MegaDork
9/27/20 10:42 a.m.
frenchyd said:
Donebrokeit said:

Wouldn't a G.M  small block unit work?

Sigh,  you are aware that most small blocks make a lot less power than a V12. Look up the difference between gross or Advertized horsepower and SAE net. 

That's why you need a big block. 

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