TR2/3/3A Carrillo Pro-A Conrods in TR2/3/4?

[Alan_Myers]

Hi all,

I'm a few months away from rebuilding my TR4s motor and have a couple matched sets of original conrods on hand, but am exploring other options.

Does anyone have any experience with Carrillo Pro-A conrods, or similar, in a 4-cylinder TR?

I ask because I'm trying to find some middle ground between original (weak) conrods and the much, much more expensive, (but very good) Pro-H Carrillo conrods.

The conrods in the TRactor are probably it's weakest point. Especially 40+ year old ones, no matter how well they are reconditioned!

But, the main alternative, H-beam type conrods, are extremely pricey, from Carrillo or anyone else. By the time this much is being spent, might as well go to a billet crankshaft, too (open up your checkbook!).

Plus, using H-beam conrods might bump a car into a different race classification (I don't know this for sure, suppose it depends upon the type of racing... autocross in my case, although it's been 20 years or more since I've been around it.)

On the other hand, it would be great to use *something* a bit improved over the originals.

I see that Carrillo now offers a much more affordable A-beam type conrod, similar in style to the original conrods, but a little lighter and, presumably, stronger (perhaps omitting the oil cross-drillings where most original TRactor conrods break?).

Whatever I end up with will be used with a good original crankshaft, 87mm AE pistons & liners (am still considering 89mm instead), and various other tuning mods such as a hot cam, Webers, header, etc.

The goal is a strong engine, with plenty of low- and mid-range, good to around a 6000 redline. I'm trying to avoid a high revving screamer that's impossible to drive on the street.

Any conrod suggestions out there? If using Carrillo Pro-A or anything similar, where did you get them and about how much did they cost? Do you feel they were worth the expense?

Thanks in advance!

/ubbthreads/images/graemlins/cheers.gif

 

[CraigFL]

I always like to look in this catalog for performance information and parts:

www.paeco.com

Order the catalog for the best info...

 

[michalotti_tr]

If you're looking to spend that kind of money, you might want to consider Cambridge Motorsports (https://shop.cambridgemotorsport.com/) "Longrod" conversion - it's supposed to reduce rotating mass and allow a higher reving engine and is available for the TR motor up 92mm in size.

 

[Alan_Myers]

Hi folks,

Thanks for the link Craig. I'll order a catalog. I wasn't aware of Paeco. The info on the website is a bit sketchy, but looks interesting.

Raymond, yes, the Cambridge longrod conversion is very nteresting. I understand with a billet crankshaft and a careful, balanced build, it's good to 7500 rpm! Probably a bit more than I need, but interesting as a kit price.

I know they use JE Pistons in those kits, which has the same parent company as Carrillo. So the conrods supplied in the kit are probably Carrillo's Pro-H.

As a kit, it's more reasonable, but did you notice cylinder liners aren't included? Add another 260 pounds sterling for those.

Also, all those longrod kit components are imported into England by Cambridge... from right here in California! That means paying import duties and shipping twice, for all practical purposes. I'm sure both the pistons and conrods are special ordered, probably in some quantity. But, I wonder if there's a supplier on this side of the Pond.

Thanks for the suggestions!

 

[PC]

Carrillo's "Super Lightweight A Beam" rods for the SB Chevy are "restricted" for use under 7000rpm and 450hp.

Since you're not looking for 225+hp from your mill I would expect the PRO-A rods to be stronger than you'll ever need them to be.


[ QUOTE ]
... I wasn't aware of Paeco. The info on the website is a bit sketchy, but looks interesting..

[/ QUOTE ]I always recommend that everybody get a PAECO catalog. Even if you don't use them/their products it's an excellent resource for seeing the kinds of operations one does to high performance engines and relative pricing. (Whether you use them or not is a personal choice. I'm not recommending either for or against. Just recommending the catalog.)


[ QUOTE ]
...I know they use JE Pistons in those kits, which has the same parent company as Carrillo. So the conrods supplied in the kit are probably Carrillo's Pro-H. ...

[/ QUOTE ]In Cambridge's TR-4 "Long Rod Piston and Conrod sets" section they don't specifically say, but if you go to the conrod pages they do say they're selling Carrillo rods and all the pix are of PRO-H rods.


[ QUOTE ]
... But, I wonder if there's a supplier on this side of the Pond..

[/ QUOTE ]It's certainly easy to get JE pistons and Carrillo rods in the US. You'll probably want to talk to your machinist and contact Carrillo and JE directly to hammer out details. /ubbthreads/images/graemlins/hammer.gif


PC.

 

[PeterK]

Paeco

I ordered a set of conn rod bolts from them. For $5 each they sent me standard 70 cent grade 8 bolts. When I returned them, they took 10% and gave me a credit rather than a refund. Nice catalog but I won't buy from them again. ymmv. Peter

 

[trfourtune]

alan,
i looked into all this before and had an idea on what i wanted. i also am in the process of a build up like yours. custom rods can be sourced from crower to any size,length specs, that you want for less than a set of carrillos and less than cambridge. also you can order custom pistons to match your rods from JE with a better suited forged material for the street/autocross usage. remember forged pistons require more clearance for expansion and knock if not up to temperature so you have to run hard (thank god).
i talked to racetorations in england an got the advise of 40+ yrs race motor building experience and i took it. carrillo of the shelf tr4 rods (std length) with (my own sourcing) british frame and engine 89mm race pistons and sleeves. (this size was strongly recommended by racetorations). 10:1 compression with 290 deg racetorations cam, this is for the street/autocross. headers, webers (i have dellortos). he states the 89mm with 290 cam acts the same as 280 cam with 87mm pistons but gives more! this give a big fat torque curve and hp to about 148 ft-lbs, 148 hp.
good luck. i have been researching for about a year for the set up i am going for.
rob

 

[trfourtune]

alan,
further note: talk to all the pro tr builders out there. most will share. some do NOT do their own motor developement. that is why i took racetorations advise. they are constantly doing tr 3-4 motor developement.
rob

 

[trfourtune]

cambridge, if they don't say they are carrillo, ther're NOT. there are MANY look alikes out there now, some made in the orient. i don't know how good they are but beware! if they are carrillo, the seller will DEFINITELY say they are.
rob

 

[michalotti_tr]

ok, the lightbulb just went on in my head ... someone on the Stag mailing list I belong to is offering a set(?) of 4 87mm Stag pistons for sale. I wonder if these could be the pistons used in the long rod conversion?

 

[Simon TR4a]

Hi Alan, and everyone!
I am pleased to see there is still as much interest in tuning the Fergie engine on this board.
My engine is a bit milder than Alan's or Rob's, having 86mm pistons, but I have got oversize valves from Triumphtune, Chromemoly pushrods, slightly stronger valve springs and 9.75 compression with a Kent cam (Supersprint? on their website anyway, one below race) of 290 degrees duration and .310 lift.

I find the cam works very well, idles at 1200rpm and pulls from 2,000rpm, strongly from 2500.
As Rob points out, the bigger the displacement the milder the cam will act.
There will be lots of room for unshrouding the inlet valve with an 87mm bore, even more if you go 89mm with Ken Gillander's kit. If I were doing it again I might not bother with the special rods, I had to get shorter ones because the head was shaved so much so figured I should take the opportunity, but they are pretty heavy. On the other hand I have heard the stock pushrods bend like a pole vaulters pole at 6000rpm.
I had trouble getting enough fuel to the carbs on race tracks, Mosport has a straight about 1500 yards long, uphill, so your on the gas a long time, so I used a cheap impeller pump, bigger line, and Holley fuel pressure regulator. This shouldn't be a problem in autocross!
Obviously you are concerned about rod strength, being on a budget I used stock rods shotpeened, but shift at 5500rpm, no problems.

Recently I took off my header, which was from Moss, and put a port matched cast exhaust manifold on. The old header tubes turned downwards immediately from the ports, and the primaries were very short, so I don't expect to lose much by doing this.
I have asked for help on some questions from Greg Solow, the Morgan Doctor, and Uncle Jack Drews, well known TR4 vintage racer, and can get informed opinions from these guys if you need specific advice from an expert source.
Hope some of this may be helpful!
I am sure many will be interested to hear progress reports from Alan, Raymond and Rob.
Simon.

 

[Alan_Myers]

Hi Rob,

Good info! Thanks! I'll check out Crower, too.

After 25+ years TR ownership, I only know enough about performance tuning them to realize how much I *don't* know (and be a little dangerous). /ubbthreads/images/graemlins/wink.gif

Yes I'm doing the same sort of research you are (thus this question!). Have had several loooooonnnggg discussions with Ken at BFE. After all, he's been performance building and racing TRs since he bought his TR2, which happened to be the same year I was born - 1955! BTW, he also strongly recommended the 89mm setup, not just because he sells it. And, a lot of the stuff he sells is sourced from Darryl at Racetorations.

Ken at BFE, DKU at Racestorations, Neil at Revington and Chris at Cambridge probably are among our best resources for info about performance tuning 4-cylinder TRs. But, they each bring some personal biases for the products they have developed and sell. And, to some degree, they are into different types of performance tuning: I think Ken's focus is on vintage drag racing. Neil is a bit specialized in rallying. Chris and Darryl are more vintage road race oriented. Wonder if we can get Kas Kastner himself to consult? He built Production cars for endurance. His books are the next best thing, I suppose, but sometimes recommendations found in them are NLA or have been superceded by even more improved products (or, worse, are now only available as poor quality knockoffs).

Roger Williams "Improving..." books tend to have more current product info, but are mostly focused on what's available in England and based on sometimes conflicting advice he gathered from Cambridge, Racetorations, Revington and a few others. His compilations aren't necessarily based on firsthand experience or entirely unbiased. Plus, I simply don't always agree with everything he has to say. For example, he prefers and recommends the J-type OD, I prefer the A-type. Still, I often recommend his books as a very valuable source of info.

I *was* planning to use a set of AE 87mm pistons & sleeves already on hand, matched up with the best set of recondition stock conrods and a good recondition stock crankshaft. However, BFE's 89mm kit is tempting and not *too much* more expensive. Camdridge's longrod kits, or any equivalents that might be found on this side of the Pond, are interesting to me, too.

I understand some forged pistons are now being made in materials that are less prone to expansion and can be run with less tolerance. Don't know, though, if that includes any of the ones we have discussed or if any are available for TRs.


I still have a lot questions and some conflicting info. For example, I'm still going back and forth about a rocker setup. Cambridge's 1.5:1 double roller rockers appeal to me, but Ken it trying to convince me rollers are unnecessary and less reliable than the stock rockers. On the other hand, stock rockers are actually something like 1.44:1, so throw of my new cam specs a little (#149 grind: 282 duration, 287 lift at the lobes). On the other hand, Racetorations has a very sensible upgrade: a rocker shaft pedestal kit that provides shaft end support, a known weakness, but it might be only usable with stock rockers.

I'm also considering using the new "GT40" cam followers that Racetorations and BFE offer. I have a brand new set of lightened, drilled & phosphated TR tappets on hand, but the GT40 type, which are used with sleeves, are getting really good reviews.

Another thing, when it comes to big end and crankshaft bearings, Ken at BFE says pretty much anything currently on the market will do. On the other hand, he probably rebuilds his race engines annually, so doesn't worry about long term bearing life. I've always heard Vandervell were the best and most reliable available for the TR 4 cyl. motor, but see that Vandervell, Clacier, AE and others are now actually all the same company!

Oh well, I guess it's just a matter of making a decision based on the best info we can track down, then moving on and getting the car back on the road.

If you are interested, some other details & photos of my project are at the link shown by my signature, below.

Thanks again.