1 2
JohnInKansas
JohnInKansas Reader
6/19/12 8:35 a.m.

So now that I finally have the TR4 at home (vs at my folks' farm), I don't really know where to start.

My plan for the final product is a street-legal GPrep autocross car. Started and ran a couple weeks ago, first time it had started in several years. Seemed to run okay, didn't take it out as there was a bad leak from the fuel pump diaphram. Rebuild kit is on order, should be here in a few weeks. I've definitely got brake work to do, need to check all the lines, make sure all the wheel cylinders are operating normally, bleed the system. I need to check the fuel tank; I suspect its a little crusty. I had issues with engine response to "snap acceleration" when I last drove it. Engine hesitated when I put my foot back in it exiting a corner at 40-60mph. I want to get it across a scale before I start stripping unnecessary bits so I can get an idea how much weight I removed. Planning on pulling fiberglass molds of the exterior panels, adding flares where required. Haven't decided what size wheels/tires I ought to go with, which will influence what size flares I incorporate into the molds.

My gut says get the fuel pump fixed, installed, drive it around the block a couple times. Park it, and do a full check of everything. Fuel, brakes, suspension, frame, electrical, cooling, etc. Make a to-do list based on that.

The rest of me wants to get started now.

Looks like things I can do before fuel pump include fuel tank removal/stripping/installation, brake system diagnosis/repair. Anything else I should look at while I'm waiting?

I can update this thread as I progress through the build.

oldtin
oldtin SuperDork
6/19/12 8:56 a.m.

Get it working, safe, reliable first (hydraulics, fuel, electrics - make sure it's not going to set itself on fire the first time out). second after memorizing g-class rules would be perhaps start on the suspension - you'll want some camber at the front so you have a few options like shortening the upper a-arms or if you swap out TR6 lower a-arms and mounts you can shim them out (I like that option better than cutting the uppers) - front sway bar - you can probably do without a rear one or pretty small. Steering joints, ball joints, suspension bushings. Oh, if your body mounts are 50 years old, it might be time to swap those out. Probably not as relevant for auto-x, engine oiling - baffling/gating the pan and maybe a rocker arm oiler. Maybe not as sexy as starting with fat tires and flares, but there ya are.

Edit for gratuitous pics - My first TR4 and first sports car, Current TR4 - getting a second life as vintage racer,

Joe Gearin
Joe Gearin Associate Publisher
6/19/12 9:00 a.m.

You may get some good input if you post this over on the Classic Motorsports website as well.

http://classicmotorsports.net/forum/classic-cars/

oldtin
oldtin SuperDork
6/19/12 10:14 a.m.

Awakening a sleeping mgb checklist ok - so not a triumph, but not a bad checklist to go through to get you moving.

JoeTR6
JoeTR6 Reader
6/19/12 5:34 p.m.

That looks like a TR4, not a TR4a, so I assume a it has a solid rear axle. If it was an IRS car, I'd replace the rear hubs with beefier units (Richard Good or Corvair hubs) before autocrossing. We had problems with the front stub axles flexing which led to pad knock-back and weak brakes on the first pedal press. Consider putting thicker stub axles and aluminum hubs on the front, or at least have the hubs magnafluxed. Upgrading the suspension bushings with nylatron helps quite a bit. As for wheels, we're using 16x7 Panasport racing wheels which don't rub on a TR6 but may have issues on an earlier TR. 225x50-16 works pretty well for us.

Another thing that helps for autocrossing is ditching the crank-mounted cooling fan for an electric one. We have a thermostatic switch and a manual override to keep the car cool while sitting in grid.

JohnInKansas
JohnInKansas Reader
6/20/12 3:10 p.m.

Thanks for that PDF, Tin. That looks like a reasonable way to get started. There isn't very much on that list I haven't done since I've owned the car (9 years this week), but it has been a while.

JoeTR6: Solid axle out back. I'd heard about axle failure. I stripped the splines off of one of the front studs last night, so depending on whether the hub stripped the stud or the other way 'round, I may be replacing the front hubs anyway. I can't run wheels that big in GPrep, largest they allow on a TR4 is 15x7. Found a setup for 15x7 with 225x45 meats that would run about $650 (wheels and tires), haven't pulled the trigger. Plenty else to do before I get to the "fun stuff".

What about roll cages? I had planned on roll hoops behind the seats with proper bracing, preferably one I could add onto to make a full cage at a later date if I decide to road race or something. Any reason to go straight to the full cage and bypass roll hoops?

Edit: something like this

oldtin
oldtin SuperDork
6/20/12 5:06 p.m.

Check out konig rewinds if you haven't already (15x7 minilite reps) - with a sponsor package you can get them for $75/ea. Most of the rear axle fears/stories revolve around the one that broke going around the carousel at Road America. Dramatic roll...I think there was a second one that hit hard on turn 5 at RA as well. So now some of the midwest sanctioning bodies want to see a southwick conversion (that shop no longer exists - guy works out of a home shop - hit or miss of actually getting one now) or a ford 8"/floater axle. JoeTR6 called it on the hubs/spindles - with sticky tires the stock spindles will flex/knock the calipers back - resulting in pucker moments on the brakes.

Christian "Mad" Marx has a well-driven/sorted TR4 - stock rear axle, stock rear springs. I think he runs around 3* neg camber and a decent sway bar up front (he shortened the upper a-arms btw). No idea what G-prep allows on the engine. Marx has several engine mods, but not to the point of having a 31 minute motor for a 30 minute race - seems to keep his revs under about 6500 and uses 87mm pistons. You'll also notice shifting sounds on the video without his hands leaving the wheel - OD unit with switch on the wheel by his left hand.

As far as a cage - the triumph ladder frame is a little flexy. A full cage can stiffen that up - especially if you run a couple of tubes from a front hoop to the spring towers, but you'll also add any weight savings and probably more back into the car. I've come across a few racers with ratco frames under them. The ratcos are 2x3 tubing instead of triumphs pair of c-channels welded together.

JohnInKansas
JohnInKansas Reader
6/21/12 9:20 a.m.

Yeah, I've heard plenty about Tony Drews' accident. I remember looking for the Southwick kit with no luck, that would explain it.

Those Konigs are sexy. I didn't find any info on sponsorship on their website, I don't suppose you've got a link?

Familiar with Christian. Haven't talked with him, but have seen his videos and seen that he's active on a couple of TR forums. GP engine mods are as follows: valvetrain unrestricted (valve size limits apply), minimal rebore, increased compression ratio, any metal pistons/rods, any crank with stock angles. There's plenty of room for building in the rules. Pretty much, it has to operate (mechanically) the same as original, and can't do a big bore, but anything else is fair game.

RATCO is on my bookmark list. Outside my budget for the moment, but may be in the cards down the road. Roll cage/hoops are high on my list, want to get that taken care of after reaching roadworthiness and before doing too much race modification.

JohnInKansas
JohnInKansas Reader
6/21/12 9:37 a.m.

Also, I find that I am mistaken about maximum wheel size in GP. Max for the TR4 is 16x7, not 15.

oldtin
oldtin SuperDork
6/21/12 10:20 a.m.

The konig deal is through nasa - so you could sign up for nasa-x and run with them a bit to qualify. I'm supposed to stick with 15x 5.5, but looking at what people are actually using says go for the 15 x 7 rewinds. The pic of the red car - I think that one runs a couple of flat sided mikunis. The claim is they work better than dual webers (which in vintage here will get you bumped a class higher over SUs or ZSs). Other than that, looks like GP engine mods are similar to vintage DP. For my first round - nitrided stock crank, forged 87mm pistons - decked for 10.5:1, bigger valves, 300* cam - the idea being a reliable engine with mid-pack capability and see where my driving is. Would have loved to spring for the billet crank and carillo rods, but the budget says no.

I've just had a few e-mails with Christian about the viton rear seal - I ended up having the scroll seal tweaked to take a mopar seal - plug n play from any NAPA...

konig sponsorship form

JoeTR6
JoeTR6 Reader
6/21/12 12:08 p.m.

I saw Chip Bond's DP TR4 several (at least 10) years ago and got a chance to look it over. He had a very nice "safety cage" that was essentially an upper frame. It connected to the front suspension towers, ran through the firewall, and connected to the rear frame rails. The dash hoop and main roll bar connected to the frame mounts, IIRC. He said it stiffened the car up quite a bit. I believe he stopped racing it not long after, and can't find any further info on Google. The Friends Of Triumph guys should know everything about prepping a TR4.

Good luck with the build.

JohnInKansas
JohnInKansas Reader
6/21/12 12:31 p.m.

Either of you fellows a member of FOT? I seem to recall you have to be invited to join.

emodspitfire
emodspitfire Reader
6/21/12 4:53 p.m.

You (probably) want to make sure that the roll hoop complies with the SCCA Autocross/GCR rules...

Rog

JohnInKansas
JohnInKansas Reader
6/26/12 9:01 a.m.

I've been waiting on a (backordered) fuel pump rebuild kit for several weeks now, and probably will be for several more.

Is there any particular reason not to convert to an electric fuel pump? Universal electric pumps start in the same neighborhood as the rebuild kit for my mechanical pump.

Car's up on jackstands, wheels off, oil changed, spark plugs changed, fuel drained. Going to start on the brake system this afternoon.

oldtin
oldtin SuperDork
6/26/12 9:48 a.m.

No reason not to convert to electric fuel pump - all the track cars I know of run electric - keep in mind SUs don't like much pressure - like 2 psi - depending on the pump you may need a pressure regulator.

Not a member of FOT - probably banned for having a ford rear end - but the archives make good reading. There is the kas kastner competition prep manual - that's another resource,

JohnInKansas
JohnInKansas Reader
6/26/12 10:35 a.m.

Zenith-Strombergs for me. Don't know if they're really any different than the SU's in terms of fuel pressure. I may convert to Mikunis or Webers down the line, but not this season.

I've got the Kastner Prep manual on my bedside table. Also have "Triumph TR Maintenance, Modification, and Tuning" by J.L.S. Maclay and "How To Improve Triumph TR2-4A" by Roger Williams. Browsing Amazon turns up a "Complete Official Triumph TR4-4A (driver's handbook, workshop manual, competition prep manual)" by Robert Bentley. Know anything about that one?

oldtin
oldtin SuperDork
6/26/12 10:52 a.m.

I've got the strombergs - - just not as tuneable as SUs. I wonder how hard it would be to go with ITBs. Otherwise, have my eye on the mikunis, but I'm still not in love with this car.

think I've got all the books except the Williams one. Bentley are reprints of the manuals.

JohnInKansas
JohnInKansas Reader
6/26/12 11:17 a.m.

http://www.i-bmw.com/showthread.php?t=5318

http://www.theukmotorsports.com/2011/10/triumph-tr4-fuel-injection/

http://richmondvaclassics.com/2011/05/30/fuel-injected-1964-triumph-tr4/

http://www.triumphexperience.com/phorum/read.php?2,700,page=1

I like the idea of carbs, I know how they work and can work on them readily. I don't really understand the way fuel injection/ECUs/etc work, nor do I appreciate the added complexity. Might be worth it if there's a measurable performance advantage though.

JoeTR6
JoeTR6 Reader
6/26/12 7:57 p.m.

We're using a Holley red pump in the trunk and regulating it down to 3.5 PSI just before the Weber carbs. Webers are also sensitive to pressure, and I've read that much over 4 PSI will flood them. I'd go with Stromburgs or SUs on an autocross car. If you build the engine so it needs more flow than two SUs can provide, go with the Richard Good triple carb intake (if rules allow). BTW, we're getting ready to try an ITB intake/Megasquirt install.

One advantage of the mechanical pump is that it stops when the engine does. If you were to have an incident, you'll at least want to put a shut-off switch on/under the dash. We also wired in an inertial cutoff switch from a late MGB under the hood to shutoff the fuel pump and ignition in a crash.

I'm not a FOT member.

JohnInKansas
JohnInKansas Reader
6/27/12 1:12 p.m.

I think I'll cancel my order for the fuel pump rebuild kit, buy a new set of battery cables (slightly longer than original) and an electric fuel pump from local autoparts store, convert to negative ground, install parts, celebrate. Should get me back to operational this week rather than "sometime in July" when they get the rebuild kit back in-stock.

Yanked the drums off the back last night. Looks like I already replaced the wheel cylinders (shiny parts, new-looking rubber). For some reason, I didn't run a hard line to the right rear brake... it hasn't been connected at all. I'm going to pull and replace all the brake lines and hoses this weekend I think. If I'm going with an electric fuel pump, I'll take measurements of the mechanical pump and fab a block-off plate at work tomorrow.

Joe, you said an electric fan is a good idea. Would you recommend a pusher or puller or does it matter?

JoeTR6
JoeTR6 Reader
6/27/12 6:25 p.m.

I like the puller fans, but you may have interference problems with the crank fan adapter. We have a timing wheel in front of the pulley, so needed to remove the fan adapter anyway. I'm not so familiar with the early TR4s, though.

intrepid
intrepid New Reader
6/27/12 6:35 p.m.

If you're messing with the battery, you might want to consider relocating it to the trunk as well to improve weight distribution.

-chris r.

oldtin
oldtin SuperDork
6/27/12 6:57 p.m.

The TR4s have a long crank bolt - with the crank handle mechanism built in (even the ones without the hole in the radiator) - if you go electric fan, you can shorten/clean up things up a bit in the front and have plenty of room for a puller fan. Personally, I'd take some measurements and hit the junkyard and see what matches...but I'm cheap.

JohnInKansas
JohnInKansas Reader
6/29/12 8:55 a.m.

If I want to run an electric fan with an auto-on/off dictated by coolant temperature and a manual override (on) option, what would I need to get that set up? Specifically interested in the temperature sensor, the rest of it should just be wiring and a toggle switch.

JoeTR6
JoeTR6 Reader
6/29/12 9:14 p.m.

I used a relay to power the fan. For controlling the relay, I ran always-on power to the relay coil through a lit-when-on toggle switch in a blanking plate for the radio. I ran a second always-on power wire through a thermostatic switch mounted where the vacuum switch used to be in the upper radiator hose. I'm not sure TR4s had those, but you should be able to find the tee fitting easily enough. The sensor was an American part that threaded directly into the tee fitting, but I don't have the part number handy. You could always adapt a sensor to fit or braze a fitting onto the radiator.

1 2
Our Preferred Partners
JuldNUrWhICMxds2pisTTqsdz5zuKuPfTgFsvKDSZdiAZvMrT44ShmDIcUl07kWX