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TR6 building a High performance TR6 engine

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hondo402000

hondo402000

Darth Vader
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I am starting to think about building my TR6 engine, not in too big a hurry but would like opinions, here is what I have thought of doing so far
bore out, not sure how much
new pistons
new rods
index the crank
0 deck the block.
new cam not sure what lift and duration
lifters
already have 40 DCOE carbs
balance all rotating components
line bore the main bearings
add cam bearings

what else is there to do?
 
You will get an ear full here on that subject. Just stick around and wait for the opinions to roll in.
 
nitride the crank

if you want parts recommendations - how much do you want to spend and what hp are you after? Street or race?
 
There are a couple of the TR6 Competition Preparation Manuals on ebay, they're a good place to start:
here it is

The two on ebay now look like they may be copyright-infringing photocopies, with all the poor reproduction of photographs, etc. that goes along with cheap illegal bootleg stuff.

You'd probably get the best info straight from Kas Kastner's latest books, sold on his web site:
https://www.kaskastner.com/kasbooks.html
As he says he's updated it. I plan to get one Real Soon Now.
 
Keep in mind that Kas' primary goal was building full race engines.
Billet crank
Carrillo rods
Aluminum head (anyone heard anymore on this?)
 
When you finish building out a budget for this let me know. I am really curious about the cost of doing all of this.
 
Don't forget about roller rockers and go up a ratio or two. 1.55 or 1.65:1. Stock is 1.46:1. Don't go to crazy with the cam or you will hate driving on it the street. You've got to decide what you want to do with the car. Do you want a crazy go fast machine and spend a lot of money on high octane or racing fuels to make it run right and can't take it on long trips. Or a stock car which is ok. Or a car to look good and out perform a stock car. Remember don't street your race car and don't race your street car.

Unless your cylinder walls are worn out save your money on punching out the cylinders. You can archive higher compressions by just shaving the head. Don't go much over 10:1 for a street car. Or you may need over 94 octane. Getting hard to find and big $$$$.

Read all you can about cams. That is the heart beat of your motor. Build the specks of your motor around the performance of the cam. The competition manual was the best thing for me when I built mine. Smart thing too not being in a hurry. Larry
 
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Let your machinist determine the overbore. Basically, whatever the next size needed to correct any problems in the cylinders.

Increasing the ratio of the roller rockers will also alter the cam lift from the advertised numbers. Take that into account. Which brings up a very important piece of advice. All of the things you listed need to be considered together, as a system, because that's what it is.

Also, don't forget about the head. More than just skimming it to increase CR. More power can be unleashed through head work than is often considered. Mostly because good performing head work is not cheap.
 
Good ignition, Either Allison/Crane or coil over. Allison Crane lets you use the distributor and maintain mechanical tach. You should be able to find a good hotrod shop that can install weights and springs. Lighten the flywheel. Either get one of the steel flywheels or get a good machine shop to lathe the outer part of yours. ARP bolts and studs. When you get it apart get a good machine shop to replace the rod bolts and check the rods. If not too far out of shape they can be used for quite a lot of horses. Short primaries on the exhaust with a collector as long as you can get it to fit, heat shield under the intake manifold, make sure that someone does a basic port match of the manifold to head. go with the later oil pump, check the oil supply passageway in the head that feeds the rockershaft, possibly enlarge it just slightly, make sure all oil passageways are deburred, Especially on the crankshaft. Make sure you go with some sort of breather system to catch the pcv fumes/oil. If you go with an electric pump you can blockoff the pump orifice(bigblockChevy plate) tap it for a pcv valve and hose it from the valve cover. Do a web search for Engel cams. Ithink this guy knows whereof he talks(and makes) for cam usage. Upgrade the springs. and wouldn't hurt to put valve seals on. If you upgrade the valve retainers, stay away from aluminum. Cost is not much more for the titanium and they are SOOOOO much stronger and more reliable. pin the thrust washers.
 
at this point I do not want a race car for the street, I would like to build an engine thats better than stock but still streetable,and reliable as far as the cam, the next one up from stock, if that makes sense? I would prefer to over bore at min 020 maybe 040" Roller rockers, I plan on just getting numbers for parts and pare down if it gets out of hand. this project is probably more than a year out, My engine runs well its the oil leaks that have me thinking of going forward. I was hoping guys out there that have rebuilt engines could tell me what they have done and where they got parts, like really good pistons, rods, cam etc
 
My suggestion in that case is to not go crazy. I call expensive parts engine porn (there is an illicit thrill about having them) and it is easy to get carried away. You can spend 20k easily on an engine, and still think you missed something...

For what you are looking for, the stock pistons, stock rods and stock crank (though for the crank, nitriding or freezing is usually not a bad thing) are all going to be good enough. Spend some money to get them balanced. You already mentioned line boring and cam bearings, both good ideas.

Spend the rest of your money on the head and the cam. Better valves, port work and a suitable cam. You could do worse than a GP2 or 3. I assume the carbs are triples, if not look into them.

I know you want a list of parts or what other people did, but other people that built monster engines usually did so with a specific goal in mind. If you want a street car with a bit more oomph, then don't start looking at (for example) a billet crank or carillo rods.

The 5k you'll drop on these two things alone will get you most of the way towards having a nice rebuilt streetable engine with 150hp and no reliability worries.

Uprated parts to consider that are easy to overlook are the waterpump and the oil pump. Roller rockers probably aren't a bad thing. Also spend some money to get whatever lifters you buy checked for hardness.

The only other thing I'd suggest (and I'll get flamed for this) is that unless you are comfortable tuning the webers, look into the triple ZS setups for the street.

A couple of places to try as a starting point for pricing are probably APT and Goodparts. I bought a bunch of stuff for my engine from Kai at Wishbone also.
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]The 5k you'll drop on these two things alone will get you most of the way towards having a nice rebuilt streetable engine with 150hp and no reliability worries. [/QUOTE]

Which are the two things you are talking about. The billet crank and carillo rods or the balancing the stock crank, rods and piston, combined with head work?

Also, just out of curiosity, how much are you looking at to get a head ported, polished, new valve seats, and port matched? $500? $1000? $5000?
 
The crank and rods. Carillo rods are about $1800. Last I looked a billet crank was coming in at $3500.

The cost of those alone will pay for all the machine work. And probably leave a little over for parts.
 
Someone asked: Also, just out of curiosity, how much are you looking at to get a head ported, polished, new valve seats, and port matched? $500? $1000? $5000?

It cost me about $1100 to have the head port-matched to the intake, new valve guides, new hardened ex. seats, new ex. valves, shave the head, unshroud and CC the cumbustion chambers. Add to this a new cam (GP3) and all of the other crap you will replace while in there (motor mounts, gaskets) and I spent something over $2K.

It's fun though....
 
Okay, the oil leakage and consumption thing, increased reliability.

My recommendations. strip the engine. You might be pleasantly surprised and find minor to little cylinder bore wear. I've torn a couple down with well over 50K on them and they did NOT need overbore, just a surface hone to reseat the rings.

New seals and gaskets. Whenever you can use FEL-PRO for gaskets and update the seals, take the originals to a bearing supply house and have them size to a Chicago Rawhide or National. Seal material and springs have improved immensely in the last 40 years. Install the cam bearings and a line bore would help. Lighten the flywheel for now, you can spend the money for the steel when you go full tilt in three or four years. A good machine shop can lathe down the outside high spot of the flywheel cutting off a good 5-6 lbs. I believe mine lost 9, but it's been so long ago, I can't remember. Have a good machine shop rebuild the rods, they check for trueness, stretch and roundness of the big end, resizing them if needed, replacing the bushings and bolts. Nitride the crank, balance the bottom end. pin the thrust washer to the cap, deburr all oil passageways,crank included, chamfer the oil holes on the crank, valve springs upgrade. Ken Gillander is who I bought mine from. Get a machine shop to install valve stem seals. I urge you to do a little research on Engel cams. He knows his stuff, can grind you a cam to fit YOUR needs and desires. Heat shield under the carbs, good ignition, drive it.
 
bobh said:
Keep in mind that Kas' primary goal was building full race engines.
Billet crank
Carrillo rods
Aluminum head (anyone heard anymore on this?)
Click to expand...

I haven't read his TR6 preparation manual. His GT6 manual has a section on "Building a hot street GT6".

I also think any diligent research would certainly include his latest books on the subject.
 
Just remember that most every performance 'upgrade' or 'improvement' will come at the cost of reliability.

Stronger pistons? They need increased sidewall clearance, they make more noise and have more piston slap/friction.

Higher lift/longer duration camshaft? They should have stiffer valve springs which increase the loads on the valve heads and seats. Plus they are harder on rocker arms.

An overbore on the block means less iron to absorb the engine heat which means the engine will run hotter. Higher compression also means more heat so you may need a better radiator in traffic and hot summer days. Figure an electric fan, too.

Every modification comes at a cost...

My advice for horsepower is to spend the $$$ on the head, intake and exhaust. Use stock pistons...rebuild your existing rods...balance the rotating assembly..CHECK the linebore (most engines will not benefit from a linebore...linehone? maybe)...Index the crank? Any good crank grinder will check for straightness but any other work is of dubious value in all but an all-out racing engine. And I'm not sure why this 'nitride the crank' keeps coming up on British car forums. Unless you've got a welded stroker or badly damaged journal that has been repaired nitriding is simply not needed in a street engine. And I've never had a crank nitrided in many years of drag racing and circle track racing and I've never had a crankshaft failure.

My 2 cents...may the beatings begin...
 
The TR 6 crank is not the best design in the world. Good strong torque motor but only 4 main bearings, minimal counterbalancing on the journal weights. Notorious for flexing(we used to call crank whipping back 30+ years ago). Where sustained rpms over 5300 and you're gonna find your crank flexes and cracks. I'm not talking about keeping the tach redlined, all it needs is rpms up above 5K for any period of time repeatedly. Sets up a stess fracture on several of the journal to counterweight junctions.

Ideally it would be 7 mains(like the Toyota Supra 6) Fully counterweighted, Any good late high performance aftermarket crank, and 4 bolt main caps or at least reinforced girdles. With counterbalancing you do not need(as much) the nitriding or steel, even a good cast iron will work.

From what I can read, he's trying to increase ouput and reliability, especially reliability, with a good water pump and perhaps 4 row radiator should not have to worry about overheated by overboring. May not need to go any over 20 over anyway. Remember that when these engines were designed in the mid=60's, there wasn't alot to do to hop them up, other than cam, carb, compression. Now metallurgy, flow science, ignition science, etc. can increase the performance without sacrificing the reliability.
 
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