i was going by Counts numbers, saying 256 cam period, for the AM engine!
there is so much more than lift and duration.

 

was runnin thru some of my old pix! a little off topic.
came across this interesting engine, Chevy 4cylinder for a lowly Cobalt coupe!

dyno sheet ,check the torque, and the boost #s, whoda thought from a street engine!
GM is great for giving a detailed book and part numbers to build it!

yup 1400hp,, 900 lbs ft, 9000rpm, and amazing 52 PSIG boost.

the hp junkies will appreciate it.

that engine is for the race car,, other pix are for the street car, to go out for fast food,(Macdonalds,, Wendys, ETC). read the street performance figures on the window sheet.
i dont think i want to run him! LOL.

 

Count. I've been investigating the inlet ports on the late model heads, (I presume they are still AJ34 heads) and wondered why they have the asymmetry. Turns out the inlet ports are offset by about 1/2" from the centerline of the combustion chamber. Why did jaguar do this? - To clear the water outlet ports on the front of the engine? I'll have to dig out my 4.0 heads and see if they have a similar offset.

Doesn't look like there is much one can do to straighten and even out the flow.

Question: On a supercharged engine, what might happen to the midrange/low-end power if I enlarged the ports to straighten them out? Too big of inlets might not be good?

In my build I plan on fitting a front fed supercharger. It has inlet port runners that are vertical and a lot longer than originally on Jaguar and I will mill inlet adapter manifolds to adapt to the new inlet manifolds. It is a 3L twin screw with a signigifantly higher effieciency that will pump in a lot more air into the engine. Based on this, how much do the inlet port shapes matter versus the stock shape?

 

Hey Count Iblis, any updates/progress on your project engine?

 

Hey TI, sorry for the delayed response:


To answer your question- let me reference what I wrote earlier


"....I can still see the nasty asymmetry forced upon the ports by the AJ34 design in an external consultancies misguided attempt at trying to boost swirl levels. It is far better on a pent roof engine to try to boost tumble. Tumble can increase turbulent kinetic energy at TDC in conjunction with appropriate squish, and can be used to mitigate knock limit AND dilution tolerance. Swirl can be used to boost dilution tolerance and mixing. Mixing is more important on GDi engine and on diesels. On Port injected engines mixing is typically less of an issue as atomisation is dictated by the fuel injector, targeting, mounting location and nozzle design."


The 4 litres whether they are the AJ26 or 27 do NOT have the assymetry

 

No, sorry,
been occupied by work and getting into my Mopar 7.7 litre build. Designing my own cam for it- a pushrod valvetrain-getting it to rev to 7500 rpm, working with Comp.


The Aston engine has left a nasty stain on my workshop floor though.


When I start to get very deep into the Jag engine build I promise I will keep everyone posted.


1st step is to get the X308 XJR running and sort out the rear end

 

Hi Count. Another oddball question For that high of a redline on your big block, will you be using beehive springs? They seem to be a easy and lower cost way of reducing weight in the valve train.

Cheers,

[QUOTE=Count Iblis;1422845]No, sorry,
been occupied by work and getting into my Mopar 7.7 litre build. Designing my own cam for it- a pushrod valvetrain-getting it to rev to 7500 rpm, working with Comp.

 

GGab, I'm looking into using Beehive springs. They usually negate the use of double valve springs, allow better package space for the rocker arms, and allow the use of a lighter keeper. I may have to use titanium valves to get the valve mass down from 140 grams to a more acceptable 90g. my biggest issue is that with Jaguar Direct acting valvetrain Im used to natural frequencies of the system of about 900-1200 Hz- which allows the system to rev, with the Big block Mopar oushrod system its down at around 600 Hz, and I may have managed to get it up to around 800 Hz (Chevy LS engine is around 740 Hz) but will it be enough. That's what Im looking into now.

 

.

many years back for a short oval short track car(Sprint today) i built a typical SBC chevy 327cu", forged aluminum 13-1 forged M/T pistons fuelie heads(hey thats all we had in 1964). factory swirl valves ,

what was different was the cam/lifters, and dual springs, from CHET HERBERT California, the unusual thing was the roller lifters, the body was made from some Viet Nam era military billet aluminum(lot of secret stuff in Cali back then).

engine had no problem revin 8500 rpm , and lasted 18 races without a teardown!
owner sold the car in winter and never heard from again!

i still think about those aluminum lifters!! they were machined billet and had a strange green color coating, and most interesting was to keep lifter from rotating Chet used steel square rod that installed from the end of oil galley all the way thru the lifters for the lentgh of block held in place by screw in plugs.

that guy was way out of the box when it came to cams and valve train, anybody remember his 400* cams, hey there is only 360* in a circle.
RIP

 

Hey Ron, these are the lifters today I've found that are probably similar, they have good control, and allow for higher revs.


Morel Lifters - Performance Lifters


For the record, I'm not affiliated to the company and am not trying to advertise, neither are any pushrod accessories even relevant to Jaguars ;-)
But this is still interesting if you're of an engineering disposition
The other company I came across was Scorpion and their high revving roller hyd lifters.


I need to bush the lifter bores and control the oil supply- trying to find a machine shop that can do that is tough. Quite specialist

 

.

good luck on finding a machine shop familier with bushing the lifter bores,
hoping the original bores are accurate,relative to the cam lobes.

YIKES that sound tricky, YES gotta love engines to appreciate whats involved.

 

also in 1964 ,i had a Factory Ramcharger prepared Dodge Coronet.
came stripped,not even sound deadner, no rear seat only cardboard shelf.

426 MAXIWEDGE, torque flight(Yuky buttons),3.90 LSD rear.

it was reasonably fast, most important i did not take the sticker on dash serious!

said "this vehicle not intended for street use" DUH.

well i was out hunting any thing with wheels, many nights.

Yup overheated it and cracked the heads and block right up from mains to cam bores!

went to dealer and he said read the warrenty book ,nope nothing unless i was winning races at a track with proof!

that was a very special engine,short ram dual 4 barrels, big port heads, custom rockers and springs, steel crank, rods, hi-comp. pistons, lot of small improvements.

big cast exhaust mani. ,aluminum bumpers,(brakes were a joke).

sugar happens ,winter came ,snow covered it , DAD said get that junk out of yard, well i was off to some girl friend or somthing , came home one day car was gone ,dad said,it went to junkyard.
he who hesitates, loses.

back then,young and dumb,"easy come,easy GO"

 

Ron, thanks for that interesting insight!


I saw a lot on the superstock Max Wedge stuff but didn't realize just how undomesticated the equipment was.


If anyones interested


This covers some of it-




Those cars were super light, like 3000 lbs with the 413 and 426 Max wedge style motors and over 400 Bhp.


Incidentally a failing of the 440 style motor from a flow perspective is the shallow/low roof height intake ports of the engine. The intake valve length is only about 4.85 inches. COmpare this to the equivalent Chevy.


The Max Wedge style engine has a bigger port and higher port roof height.


Intake valve length of the Max Wedge style engine is about 5.4 inches by comparison.


The Mopar stage VI heads I'm using are based on the Max Wedge geometry for this reason...although I intend to have better cooling that Ron had on his Superstock!

 

altho the Max wedge engines were great for drag racing ,not so good for Nascar or street use, anything related to endurance use!

when i had the engine out and stripped down , all you had to do is pick up a standard 383 iron head, vs a 426 Max head the weight difference was at least a 1/3 lighter for max head!
the big push around the 60s was to make thin-wall castings, blocks and heads, fine for racing as long as you didnt overheat, thin wall cracked easily!

course aluminum became the answer, then money no object Magnesium blocks came along, if it wasnt for Viet nam war production there woudnt have been any foundries to cast such stuff, government paid for the technology to do!

oh well ancient history today

by the way, my Dodge was RED

 

oh well ancient history today

by the way, my Dodge was RED[/QUOTE]

But still fun for the rest of us to hear about

 

Amazing thread and thorough analysis.

I'm embarking on something similar, so some questions if the Count/anyone can answer ..

1. Crank Shaft: using the AJ37 is a great idea, so I'll start with that. Would want a 93mm bore and a 93mm stroke.
2. Pistons: for that stroke and bore. Thinking TRW forged pistons.
3. Piston Rods: For that stroke and bore, need connecting rod dimensions to have these custom made. help anyone?
4. Heads: AJ37 heads, as suggested. Has the Count actually made/modded the cams? care to share?
5. Blower: thinking of a Kenne Bell 2.8LC or 3.6LC. Thoughts?

 

My first comment: You better start reading up on everything you can find about rebuilding custom engines from the ground up. There are absolutely NO aftermarket parts other than a stock rebuild. That means almost every component in the bottom end of the engine will be custom. Pistons, rods, sleeves/block, crank. If you build it, yourself budget at least $10K to $15K for parts. If someone else builds it, plan on $20+K.

Replies to your posted items.

>Crank Shaft: using the AJ37 is a great idea, so I'll start with that.
Good luck finding an AJ37 crankshaft for sale! I've been looking for a couple years now and haven't found one under $5K. Easier to purchase a complete engine than it is to find the crankshaft. If you can't find an AJ37 crank, custom cranks in the USA start at about $3500, and only a few shops will actually fabricate one at a time without an additional $3K to $5k engineering charge.

>Would want a 93mm bore and a 93mm stroke.
93mm bore wont work! 96mm cylinder spacing. 3mm between the edges of adjacent walls. 92mm bore is risky, but has been done, 91mm bore is proven. (Perhaps with a very custom head gasket, you might be able to seal across 3mm. - More $$$$ - more risks.)

>Pistons: for that stroke and bore. Thinking TRW forged pistons.
I didn't know that TRW makes an off the shelf piston that will fit. Please let us know what you have found. Likely you will need custom pistons to match the custom rods.

>Piston Rods: For that stroke and bore, need connecting rod dimensions to have these custom made. help anyone?
Best you read up on how to calculate rod length. Dimensions are base on block deck height, crank stroke, Piston compression height.

>Heads: AJ37 heads, as suggested.
Good luck getting your hands on a set of AJ37 heads. Again. Better to purchase a complete AM 4.3 or 4.7 engine. $7K to $12K for a complete engine.

>Has the Count actually made/modded the cams? care to share?
There are other threads on cam shaft mod. Search the forum and read up on the topic.

>Blower: thinking of a Kenne Bell 2.8LC or 3.6LC. Thoughts?
Good choice - 2.8L KB

Reads to me like you are just dreaming about building a high HP AJ-V8 series engine. Unless you have deep pockets and pay someone to build it for you, you have lots of research ahead of you before even thinking of spending money on parts. No one is going to just give you, or post all of their research, time and effort that it took to build their engines. (They may not even remember all the details.) All you will get are snippets of information here and there. You have to make a plan and map out every detail associated with the build. Your build will likely end up being different than the few that have been successfully completed.

Good luck.

 

Agreed; I am at the research stage, so putting together a supplier list.

I've almost sealed the deal on an AJ37, so don't plan buying individual parts. Interestingly enough, I have found a couple of precision engineering/manufacturing places here in the UK who will do parts by the piece - one for another day; I have in mind to mod a Jaguar V12 6.0L engine to DOHC and a KnB Mammoth blower, so will start a separate thread as and when.

Thanks a lot for this feedback, exactly what I was looking for prior to stripping the anticipated AJ37. I was hoping I could getaway with the same 93mm bore on the Gen III engine, but evidently not.

They do a 93mm bore set, hence why I wanted to start there. Yes, there is the custom forged option from the likes of Mahle and others, so let's see how the cookie crumbles when the babe is stripped and the actual work begins.

Thanks for the feedback; I'm aware of how it's done, though I was hoping that someone else might have gone through the motions before the actual strip and rebuild to save duplication.

You mentioned that 91mm bore was proven. Did you actually do that or can point me to who did it? they'd most certainly have treaded the same path I intend to, so room for information reuse and gained experience.

Ditto crankshaft comment. I'm sourcing a full engine.

Good idea , though wanted feedback from the Count on his propositions. I'll have a search and browse of the forum.

Thanks

I'm certainly not under any illusions as to the size of the task, nor do I propose copy-paste effort/info. The one difference is that I do intend to post and share the core of the research, as well as hopefully be able to offer the mods in kit form to others or offer a build service locally.

Thanks once again for your feedback.

 

bore to bore: 98mm. 93mm is just and just ok with very thin ductile iron
sleeve if you have N/A - but it's not enough for boosted engine and specially not ok for high boosted.


I have had this grazy puzzle 20 months and tens of things have needed to resolve and make/order custom parts from all over the world.. BIG money gone and this was not the first or second big project for the same car. I would say stage 3 or 4.. But now almost completed. I hope never again back to this kind of rebuild, but at least I have enough knowledge after all of this and know what exactly to do next time.....

 

I say full speed a head and damn the bloody torpedoes! In other words, if this is your dream.

Go For It.

First the dream stage then the do stage. The nice thing about these forums is it allows you to reach out to a huge number of enthusiasts, instead of just one or 2 motor head buddies.

But what are you building the motor for?

Is this to be a street car? A drag strip or road course terror? Is this to be more of a show car, that does run snd make the power but will be more for display and personal satisfaction?

Avos has already made proven-reliable monster hp on stock (or kind of stock) Jag engines without replacing everything with the most exotic parts possible.

If you were building a N.A. then I can understand, but boost doesn't really give a crap how light the metal is, or that the heads and cams are design perfection. Sure you'll make more hp with lighter material and higher flowing designs, but how much are you shooting for?

Avos must have hit 600 crank hp years ago. He's not even using water/meth injection or running different aftercoolers. He's making it with improved flow and higher/cooler boost with his Twin-Screw Kit.

I don't think Avos or any of his customers have blown their engines up with his kit, which seems to give some proof the factory internals are strong enough to hold big power figures for.....? Has it been 10 years that Avos has been running his Twin Screw kit? If not it must be close.

What are you shooting for?