Longchamp +100 HP

It's always a bit worrying what you find when taking your engine apart. I don't think the heads have ever been off, I've never had to use so much force to loosen the head bolts before. Most looked good, pistons look like new, the wear ring is invible, feels non-existent. Only thing worrying were the pushrods, I put new in when I changed the cam in 2008, had to because of length. Two of them were obviously bent. Intake on 2 was 3mm bent, intake on 3 was 1mm bent, and maybe others. I'm not going to reuse them anyway, but is this a sign of something bad? I don't think the cam is bad, and I just took out the 16 lifters and checked the bottom, looked good. I doubt this engine has been above 5500 rpm since that cam and those pushrods were put in. Well maybe a few times at Spa...

If I remember right, one of the pushrods I discarded when changing the cam in 2008 was also bent
Why do they bend? I've never had a bent pushrod in any engine before.

Heads are off, so now it's about cleaning and making the reused parts ready. I'm also installing a carb spacer that will be modified as per Dan Jones instructions. So, short of a stroker kit or forced induction, this engine will now be at its full potential IMO

The most common cause of a bent push rod is a stuck valve.

If the engine layed without running it for a long period of time, this could have been the cause.
Better to use bronze valve guides then the original cast in iron ones.

I have seen on the 428 engines valve guides that are too tight new. It's an easy fix when the heads are off the engine though. Run an 11/32" reamer through them to make sure they are straight. 3/8" on the FE's.

When you replace the original guides with the pressed in bronze guides you MUST do this anyway. The pressure from pressing them in can distort them enough for the valve stems to get hung up when the engine is hot.

The FE's run hotter normally than the Cleveland or the Ford SB does.

A flat cam lobe could easily be caused by using engine oil with not enough ZDDP in it.

Many owners are simply not knowledgeable enough to realize how important that is?

Better to have too much in it than not enough.

Make sure you use plenty of the cam shaft break in compound on your new cam and lifters.

The first few minutes are critical and you can kill the valve train on first fire up if you don't liberally coat everything in it.

ALL of the afermarket cam manufacturers are using cast iron cam blanks from "OFFSHORE" sources. They only spot check the cores when loading them into the cam grinding machines.

A noticeable amount are coming through with visible defects on them fresh out of the box, Check your new camshaft over carefully. Do not assume it is perfect and without defects.

There have been those that used 3/8" push rods on the Cleveland for as long as I can remember. Probably just using the hardened 5/16" that you ordinarily would on a solid lifter cam with guide plates would be enough.

I did have a brand new set of Crane hardened 5/16" push rods break on me though. If you look at the push rods, they have little dimple welds that hold the round tips to the tubes.

On the Cranes, the cracked through those welds and about 4 of the tips came off into the engine on the lifter side.

I went back to the TRW Boss 351 service push rods and have never had another issue since in 30 years. I run triple valve springs also, so there's a lot of pressure on the valve train.

Never bent a push rod in a Cleveland. Yes in a 428 AND 351w.

I have heard of the lifter bores being too tight on some engines as well. Personally I have not encountered that yet though.

Maybe consider using the Wyandorff bronze lifter inserts? The kit comes with a reamer to clearance the sleeves once you press them in.

Theoretically you can do the modification on the block on the engine in the car, but you need to catch ALL of the metal debris you create from boring out the lifters and that is much simpler with the block disassembled and on an engine stand.

Incidentally, the drag racers here use a C4 automatic trans behind the Clevelands. They are much lighter and can handle the power of the Cleveland. The C6 is considerably heavier.

Doug, thanks for input. Since I'm putting on new heads, that should sort that part. I doubt the lifters bind, at least they slide down freely all of them.

Spacer work. Before:

After:
This is what to do if you have a dual plane with floors at different levels, which I think all dual planes have. Maybe that's why they're called dual planes...

BTW, does anybody know what the small hole close to the fastener hole top left is for?

Heads have arrived

Hi Mikael,
nice heads, what did you go for?
Cheers, Tim

Tim, it's Trick Flows, 62cc, 2V, for normal cam. I think the cheapest they do for the Cleveland. This engine is a medium build all the way, has to be able to drive in traffic with auto and A/C. And still outrun almost everything it meets of course...

Pretty heads.

quote:

Originally posted by No Quarter:
Tim, it's Trick Flows, 62cc, 2V, for normal cam. I think the cheapest they do for the Cleveland. This engine is a medium build all the way, has to be able to drive in traffic with auto and A/C. And still outrun outrun almost everything it meets of course...

not directly the purpose of a Longchamp ?

Damn right it is! You thought it was a quiet sedan for an old guy to relax in? Wrong, it's a domesticated race car, undercover... Soon with enough power to back it up

I agree, Mikael. I always thought of the Longchamp as a Euro-Mustang with a better suspension.

Progress. But don't be fooled, there are no pushrods or rockers under those covers. I needed different length pushrods, and no vendor in my backwards country had any length but the standard ones. So have to wait for Summit via Mike. But tried to do everything else.

BTW, this thing about getting the right geometry by getting correct length pushrod has always confused me a bit, some instructions on doing it sound counter intuitive to me. But I like this one, simple, even I could do, and the satisfaction of seeing the ink-wear pattern in the middle...
Lunati pushrod length checker

Carb sits a little higher with the modified spacer. I hope (and think) the hood will be able close.

In comparing my old heads with my new, I would like to know what compression ratio I'll get. I made a crude measurement on the new heads, 62cc, and "62cc" was stamped on it, not bad I made a just as crude measurement on the old heads, approx 75cc. Pistons are slightly dished, with two "twirl"-notches I think. Does anybody know any specifics about my old heads, and my compression ratio before and with the new heads?

quote:

I agree, Mikael. I always thought of the Longchamp as a Euro-Mustang with a better suspension.

Bosswrench, in a way: yes. But there's more to it than that. E.g. cooling fins in the engine room, cooling ducts for front discs, tri-Y headders (an option), ZF steering (Series 3). Lots of small stuff that shows they took performance seriously. And the suspension as you say, independent, rear discs moved inwards etc.

CR is gong to be just under 10:1. 9.7 or 9.8. It should feel crispier with those heads.

In order to make the car pull, you need to do something with the final drive ratio.

3:1 is not going to cut it. You need around 4:11 or better. 4:33 is actually a really good number.

Doug, do you know the ratio in my Longchamp?

Mikael, do you know if any varients of the Longchamp or Deauville used ZF steering? If so, which type of ZF steering was it?

Don't know how to edit my own posts here: during the period ZF made 'ZF-Ross", 'ZF-Gemmer' worm & roller, and ZF ball-and-nut (power) steering boxes. Which one is used in Longchamps or Deauvilles?

quote:

Originally posted by Bosswrench:
Don't know how to edit my own posts here: during the period ZF made 'ZF-Ross", 'ZF-Gemmer' worm & roller, and ZF ball-and-nut (power) steering boxes. Which one is used in Longchamps or Deauvilles?

I'm told all series 3 have them, but I don't know exactly which of the above...

Nice job Mikael

quote:

Originally posted by No Quarter:
Doug, do you know the ratio in my Longchamp?

No. I know little about the car itself. Consider though that the Pantera is 4.22:1 with a 2.20:1 first gear. When you multiply those numbers it comes remarkably close to what a Mustang with a 3.89:1 rear and a 2.32 first gear has.

I can tell you from experience though that if you want the Mustang to pull hard enough to break a 15.0 second 1/4 mile you really need 4.33 rear end ratio with that transmission.

Automatics complicate that formula though. Generally they have a lower ratio first gear and the torque converter because it slips some, adds more rpm to the engine at that point. As if the car had lower gears.

If I remember correctly, a C6 with a 3.50 rear is approximately equal to the 3.89/2.32 manual ratio?

Some people have been successful with using the 78 or so Granada transmission in the car since it has an overdrive top gear. This gives you the bottom end that you need and recovers some of the lost gas mileage at the top because of the increase rpm.

Any way you look at it though, looks like if you got around 12 mph, that's going to be about the best you can do with that car and engine setup.

It wasn't built at a time when high mileage was a major concern.

It gets 16 mpg on my commute to work

Got so far on the Longchamp I could try closing the hood with the new spacer on, there was enough room, phew

Pushrods received so I could assemble it all. Picture from just before soaking in oil. It's a shame that the valvetrain isn't visible with the engine running I think.

I got it started, idle is fine, vacuum rock steady, no ticking sounds. That's all for right now, weather and salty roads will delay test drive

Nice - looking forward to seing it back out there

quote:

Originally posted by No Quarter:
It's a shame that the valvetrain isn't visible with the engine running I think.

That can be arranged. See on Youtube
Good work Mikael. Following with great interest.

quote:

Originally posted by No Quarter:
It's a shame that the valvetrain isn't visible with the engine running I think.

I remember SOMEONE making clear Lexan valve covers maybe 25 years ago. I haven't seen them since.

It might have been small block Chevy only. Maybe?

I think they were made for racing purposes? Drag racing primarily. This way you could visually check for issues on a running engine without tearing it down.

Wow, that's a memory test for sure. Who the heck made these things?

I want to say it was one of the large camshaft companies. Check ebay. Maybe a lead will turn up there?

That companies website came up with a google search. Expensive $285 and Chevy only. http://www.clearvueconcepts.com/products.htm

don't think it keeps clean very long...just one good reving ?

and.. it would make me scared, just seeing all those moving parts...and hope they keep moving

I'd like to upgrade my not so stable acc bracket to the orig idea, see picture. Does anybody have such a thing laying around?

The bracket I was needing, I welded something instead...

Back to the +100HP(?). Last weekend it was time to drive it, to test it, was it a rocketship now? Not really. So far it's been disappointing.

The first trip I couldn't feel much difference, only that it spun its wheels more often, a good sign, damp roads. But when I got home I knew what to do, having read my own book (sorry). Ignition had just been set as per ICE's recommendations, 16 degrees initial and I set the ignition box to +12@3800. It definitely felt like too little too late, both by being slow and by backfiring a little bit. I tried to do +12@2800 (there are 16 different settings in the ICE-box), that helped, so I was right about needing to get earlier ignition. I would have to forget about the ICE recommendation and do the tuning as in my book. So I drove home, to get my pen and paper and timing light and 1/2" wrench. But parked outside and hot, it wouldn't start. Hhmm. You can't tune your car if the basic like starting and not overheating are not OK. So had to fix that first.

I'll spare you the details on fixing the hot start problem, but it involved dismantling starter and routing new wiring. Now the starter runs faster than ever. But rain had started, so no more tuning that weekend. To be continued...

One more thing that made the Longchamp feel slower than it should be was that I had no kick down anymore. Just raising the carb 5/8" eliminated the kick down, so I had to bend the rod in a few places.

So now it's ready to go tuning. Just need the time and weather to do it...

As I'm writing this I see snow coming down...

It isn't going to pull at all without changing the gearing. You could put a 500hp supercharger on the car and it would still be sluggish without the gears.

Adding 100hp to this setup won't even show in 1/4 mile times.

How much does the car weigh?

what I'm thinking is that you really need 4.33:1 rear gears with an overdrive transmission so you can cruise reasonably with it.

I'd take a guess and say you probably have something around a 3.00:1 rear ratio now? With that it is a 16 or 17 second 1/4 mile car and won't embarrass a Ferrari unless it is Uncle Luigi Ferrari (no relationship) and he is pushing a gellato cart?

Today I could test a bit more on the Longchamp. I decided to ignore all the good advice and manufacturer’s recommendation and follow the process in my book. I set the initial timing by the vacuum gauge, ended up with 8 degrees earlier timing as the best steady high vacuum. I listened for detonation, couldn’t hear any, and tested if it could start with that early timing, it could. My timing gun showed 24 degrees at idle with vacuum disconnected and plugged. That’s a lot, right? Well maybe my balancer doesn’t show TDC correctly or my timing gun is faulty. Who knows? All I know is that my engine liked 24 degrees better than 16 degrees as read on the balancer. So who cares about the numbers? I don’t. And that just goes to prove the main point in my book, you can NOT set your timing based on your Haynes manual or the manufacturer’s recommendation or your best friend’s recommendation or the fastest guy in town’s recommendation. Only the vacuum gauge and the trial and error method I describe in my book will optimize your engine! Now, you can consider this posting a blatant attempt to sell books, or you can go for those free +25-50HP a perfectly tuned engine will give you. Up to you...

The test drive felt like another car. It now easily spins its wheel, in fact on the semi damp roads this morning it was impossible to measure a 0-60, it just spun its wheels all the time. Those that have read my book knows that you can’t tune any further unless you have consistent dry roads to do it on, so fine tuning and playing with the 16 curves in the ICE box will have to wait a few weeks. I don’t expect to find a lot of extra power still, but you never know.


If you copy my way of tuning, remember to always err on the side of caution, meaning start with too late timing and go earlier and earlier until you get best performance and no detonation.

Mikael just out of curiosity how much does it advance to/max when you rev it?
Jan

Haven't checked... And if the idle number maybe is wrong, then the max will also be. The curves in the box will add from 6 to 20 degrees, I'll play with them later