I saw a higher mileage (120+K miles) 2003 STR for sale for what appears to be a reasonable price. Then I started wondering how much it will cost all us STR owners to rebuild our AJ34S engines in the not-so-distant future.

I started scouring the forum for AJ34 engine rebuilds and mods and didn't find much posted. (Only one great thread on XKR engine rebuild)

I would like to start gathering information regarding how much is costs to rebuild the engine and good shops/businesses to purchase parts and services from.

Has anyone rebuild their engine yet?
Approximate cost?
What are the strong parts? Weak parts? Any custom parts? (Like Carallo rods and CP pistons?, I read that only stock size bearing are available?)

Joe

 

Wow! a week has passed and no one has any comments/information on rebuilding an AJ34S engine?

No one has information on the crank? The pistons? The rods? Bearings?
No one has built up an AJ34S long block?

Anyone know anything about the Arden 4.5L kit?

http://shop.arden.de/jaguar/s-type/s...-auf-4-5l.html

 

I don't recall any posts here or on UK forum. One of the techs probably knows a lot but they do tend to be rather busy.

 

I haven't re-build an engine myself, but the price from Arden isn't bad at all, so I take it they are getting rid of 'old' stock.

 

I can't recall ever hearing of anyone attempting it.

Make sure you document it!

 

Generally, a good place to start with a question such as this is to either examine an engine that has failed to determine the cause, or speak with someone using the engine for racing purposes. If there are 'weak' areas, they are revealed under racing conditions.

Also, if you have access to a Technician at a Jaguar agency, they can often comment on any failures, or failure patterns that may have occurred.

 

Today's engines are not being "rebuilt" like the iron block engines of the past. The oils and lubricating systems today are much better and the inside of the engine typically shows no wear.


Cylinder heads, oil leaks, decarbonization, timing chains, etc all come into play when an engine "rebuild" probably never will be necessary.

 

When my 4.0 engine started to have an oil consumption issue I replaced it with a brand new 4.2 engine. The problem was it came from a Jaguar training center so it had been taken apart many times. To the best of my knowledge there are no aftermarket sources for the engine internals. The bearings are unique to each engine & the block has to be read for proper bearings. I did find it was much cheaper buying all the engine bolts thru Land Rover as they were much cheaper.

If you are interested in purchasing a brand new set of cylinder heads to have ported I will give you a great deal as I used the 4.0 heads. You could set these up with a set of reground cams.

 

Thanks for the input so far.

After I started this thread, I've been searching the web for shops that carry AJ34 parts, and called my local Jag dealer. I read Avos' post on his 4.0 to 4.2 rebuild, and there is some good information there.

The dealer stated that he thought the less common parts such as; pistons, rods, crank shaft, rod bearings (stock diameter only), main and thrust bearings, could be found through their dealer network. (I didn't go into price. He also stated there are a few AJ34 and AJ34S new long blocks still available in the USA. $$$ $7K to $8K.

This being a hypothetical situation, it appears there are 4 approaches to building an AJ34 engine.

1. Scrounge new parts like pistons, rods, bearings and other harder to find parts from various sources. Have the stock crankshaft reworked to stock, and assemble a stock engine.

2. purchase a refurbished/rebuilt long-block for one of the rebuild-houses that build up lots of replacement engines.

3. Have the engine rebuild by someone like Racing Green.

4. Build a custom engine. Custom crankshaft, custom rods, custom pistons, customs bushings. Perhaps bore the block out to support a 4.4L or 4.7L displacement. I've read that a few builders have put in slightly larger valves, ported the heads. Going down this path will have other challenges. ECM tuning, perhaps a larger throttle body.

I suppose it would come down to a balance of cost versus performance.

 

There is no reason to send your engine to the UK. There are many people over here more than capable of building a 4.2. I have not heard of anyone doing larger valves but do have experience with porting the heads & upgraded cams. What are you trying to accomplish? Here is a link to the company that ported my heads & uprated the valve springs.

http://stiegemeier.com/

 

$$$ will speak. I had to fix up a blown engine in a S-type V8.....that required 17 new valves plus 800 for the work. Then you add all the gaskets...chains and tensioner since you are at it, water pump - overflow tank and thermostat same reason, probably motor mounts and tranny mounts, one or two plugs, oh since you are at it tranny filter and fresh oil, new spark plugs, a couple of sensors.........then while you have everything apart you find some suspensions stuff that needs attention, then one of the wheelhubs goes bad, .....TB porting 150, then Mina gallery intake 180, hey might as well tune it......and in my case spent over 6000 in parts! Do I regret it? NO. I like thinkering with cars but make sure you have the $$$ for in case work.........I always make a budget and add a couple of thousand for just in case stuff which always comes up!.........

if this STR is what you always wanted then go for it! but if you want it soon than stick to stock stuff, add a couple of add ons like intake, pulley, exhaust and a tune and you are good to go.......remember in the US speed limit is 75mph.....now if you lived in the EU then I would say go ***** to the wall since you can do the same on the autobahn

 

I already have my slightly modded 04 STR that runs great, and my 2000 S-type conversion project. I've been thinking of adding another STR to the stable for family members to drive. If the economics work out, I've been considering purchasing another one with a blown engine, and putting another engine in it. (I don't really need another project, but I am sometimes stupid that way.) If I go this direction, I wouldn't be in a rush to get it running. Typically I like to do things that others haven't done, so I would consider building up a modded engine.

You are right about the incidentals. When I drop the whole front sub-frame I'll replace anything and everything that looks worn. Suspension, Steering, lines, hoses and all the other parts you mentioned. On my conversion build, I've spent way over $1K on peripheral parts. It adds up so fast. One worry would be weather to put in a rebuilt trans while I was at it or continue to run one with 100+K miles.

 

Question: Do the STR AJ34S engines by chance have forged cranks?

In my readings about the engine, I have read that is is cast and others have stated that it is forged.

Anyone have an estimate for the cost of a custom forged crankshaft?

 

I have no proof if it is forged, and all Jaguar documentation I have don't mention it it is, but do for the rods and pistons. I do know the stock crank is pretty strong ;-).

I guess making a crankshaft in the US will be cheaper then in the EU, here a strong forged one would go into the 2500 euros.

 

Have a read of this thread from 6speedonline Vantage V8 4.7 engine rebuild - 6speedonline.com Forums

Some good info in there about the AJ-V8, the guy has also rebuilt an AJ34S from an XF & mentions some of the details in that thread.

He specifically mentions the Jag engine has a cast crank, the AM uses a forged crank, but the rods & pistons in both engines are "cheaply made"

Oh, and don't even think about using an AM crank in a Jag engine though, the firing order is different...

Here is the guys website PRE Tuning - Site he's in Ilinois

And there is a story about the XF AJ34S rebuild on his site too 2009 Jaguar XF Supercharged AJ34S engine rebuild » PRE Tuning - Site

 

In my AJ-33/AJ-34 searches I read these postings. It is good to get a link to them on this thread. Thanks!

In the past week, I have spent endless hours searching on every combination and association to AV-V8s that I can think of. I have a growing Excel file of my findings.

It is becoming apparent to me that if I take on the challenge of rebuilding an AJ-34S engine, there will be a lot of custom fabricated internal parts.
I have found 6 sites where enthusiasts, or shops, have taken on the rebuild of some AV-V8 variations. None of them have done it completely with stock parts.

It is interesting to note that there are 3-4 engine rebuild sites that list the selling price of a rebuilt AJ43 or AJ34S for under $3,000. I wonder what the rebuild really consists of.

I found several sites in Europe where threads discuss the costs of rebuilding a Jaguar engine, and they ask the same question. I have found more sites in Europe offering rebuilds than in the states.

I believe that a few years ago, RSR? built up a Jaguar AJ based race engine. (Now they are racing the new 5L engine) They spent 35K per engine to do it. special casted block, billet crank, custom rods, 600+HP The list went on and on. Their web site doesn't mention anything associated with this older project.

I eventually will call Carello/CP and talk to them. They have made custom rods and pistons for AV-V8 engines. I have found several sites that custom make billet and forged cranks. I'll call them as well. Wiseco appears to do a lot of custom cranks, Piston and Rod work as well.

I still have the a feeling that the majority of S-types/STRs and other Jaguars with the AJ-V8 based engines will go to the wrecking yard as their engines age. They are just too expensive to rebuild for the majority of owners. It is more cost effective to purchase a newer used Jaguar. From my perspective it is looking more and more like for the majority of Jaguar owners it would be better to spend $15K to $25K on a lower mileage newer Jaguar, than put in $7K to $10K to get an older STR back in reliable shape.

 

It's really a question of volume Joe. I mean this is always our problem in the aftermarket, the volume just isn't there...

And if you can get something done, it's always a 1-off and the cost reflects that.

Aside from the crankshaft bearings being a pain to identify & source, you have to look at what the market needs for bottom end kits:

Basic rebuild:
Stock liners, honed out +0.5mm
Stock cast crank, re-ground, with Custom bearings to suit
Stock rods, cleaned up
Custom Oversize pistons, +0.5mm, same quality as stock, with Custom oversized rings
Stock bolts

Middle range rebuild:
Stock liners, honed out +0.5mm
Stock cast crank, re-ground, balanced, nitrided, with Custom bearings to suit
Custom Forged rods
Custom Forged oversize pistons, +0.5mm, with rings to suit
Stock bolts, or maybe aftermarket, ARP, etc...

Top range rebuild:
Stock liners, honed out +0.5mm, maybe even +1.0mm
Custom Forged Crank, standard stroke, balanced, nitrided, with Custom bearings to suit
Custom Forged rods, with bearings to suit
Custom Forged oversize pistons, +0.5mm, maybe even +1.0mm, with rings to suit
Full bolt kit, ARP, etc...Custom

Over the top rebuild:
Custom liners, +3-4mm
Custom Forged Crank, extended stroke, balanced, nitrided, with bearings to suit
Custom Forged rods, with bearings to suit
Custom Forged oversize pistons, +3-4mm, with rings to suit
Full bolt kit, ARP, etc...Custom

There's a lot of Custom made stuff needed no matter what you do.

I guess the point is, if someone has a Jag and the engine blows, if you look at the basic rebuild that's available now (with custom pistons, rings, and the runaround for bearings) it's sensible to buy a low-mileage engine from a wreck & drop it in, rather than re-build.

The basic rebuild on an AJ-V8 is probably the equivalent money of building a very hot small block Ford V8, with forged everything. I can't imagine what a $3000 rebuild will get you; a strip down, clean & check with new gaskets?

And then when you push into the higher levels, the costs will be very high (think Arden)

You really have to define what you want out of a rebuild....

EDIT

And then you need to think about heads, valves, cams, supercharger, etc. etc...

 

And then as you work your way back, it leads to bigger injectors, bigger fuel lines, uprated fuel pump, re-tuned ECU to make it all play nice together... the quest for power never ends.

The stock internals can actually take a fair bit of power providing you aren't careless with detonation and things like that. I think Avos has proven you can get pretty far without having to go crazy on the bottom end.

If you are gunning for 1000hp, then yeah, ok, you will need all that stuff. If you are satisfied with a measly 600, then find yourself a decent long block from a wreck, get the twin screw kit and have at it.

 

Cambo.

Very good summary! Similar to the spreadsheet I have been putting together, but I am only working from one detailed list of parts and then list my options in columns to the right. I like the way you categorized the different build levels. Succinct and to the point with all the pertinent items.

Now all we need is a cost estimate range for each category and when forum members need to make a decision on rebuilding their engine, they will have this as a reference.

I favor spending more money and making the engine more reliable and/or try for more power, but that is always limited by available funds and the plan for the car.

Take for example: My conversion car has a LS3 installed in it. An associate of mine put a LSA crate engine in a Pontiac Solstice. With the mods he has made he is outputting close to 600HP from an off-the-shelf engine. I was planning on adding a super charger to my LS3 to get the HP up to 550.
When I add up all the costs, it would be better to sell my LS3 engine and purchase a LSA, and use the same tuning/mods he has done and get more reliable HP for about the same cost. Unfortunately, I don't have an extra $12K sitting around, so I work on my project incrementally. Same decision process everyone has to go through deciding what they will do for a rebuild.

Then on the other hand, if I want to build up a 500+HP Jaguar engine, if will probably cost close to $12K when all is said in done. Does that favor a conversion? Is it better to spend the time on a conversion rather than a rebuild?

So many choices and possibilities....

 

I assume everyone has seen this forum posting....

https://www.jaguarforums.com/forum/j...tom-end-96033/

I recently read that the AJ34S heads use 5mm stems on the valves. True?
Do the AJ33/AJ34 engines use the Same valves as earlier AJ series heads?
I read that they same valve were used in the X-types.

Anyone know how big of valve stems have been fitted to the heads and/or can be fitted to the heads? I read somewhere that the Exhaust valve are just under 35mm and haven't found the inlet diameter listed anywhere.