Author Topic: Timing the twin cam  (Read 11962 times)

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Online BDA

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Re: Timing the twin cam
« Reply #15 on: Tuesday,January 20, 2015, 07:46:52 PM »
blaster, would it help if I you knew how much they cost now? (Here's one that was nice at one time - nicer than mine - but now need block and head repair: http://www.race-cars.com/engsales/cosworth/1414985251/1414985251ss.htm) I was lucky and had mine built a long time ago when it was merely expensive. There are several people who have adapted the Toyota 4AGE (which is basically a Japanese BDA) to their Europas. It requires a bit of fabrication and wiring work, but it should be really good and a lot less expensive.  :)
« Last Edit: Tuesday,January 20, 2015, 08:07:41 PM by BDA »

Offline blasterdad

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Re: Timing the twin cam
« Reply #16 on: Tuesday,January 20, 2015, 08:33:00 PM »
 :huh:
WOW, you would think that after 2565 views someone would have snatched that up by now!  ::)
Even comes complete with melted cylinder head!  :o
I think I'll stick to the ol' Renault...  ;)
P.S.
Congrats on getting one while the gettin' was good!  8)

Offline buzzer

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Re: Timing the twin cam
« Reply #17 on: Saturday,January 24, 2015, 01:28:04 PM »
An expensive bit of furniture at $14k.
Dave,

Other cars. Westfield SEiW. BMW E90 Alpina D3. BMW 325 E30 convertible and Range Rover CSK

Online BDA

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Re: Timing the twin cam
« Reply #18 on: Saturday,January 24, 2015, 02:13:30 PM »
I had heard that good (running) BDAs were going for about $20K+. I know the head can be fixed but I have no idea what it would cost. Of course you would then have to assemble it. I guess a lot of the price is for the alloy block which would be nice.

I don't think it makes sense to put the value of a finished Europa into the engine for that Europa, but thinking about it for a bit, I really pretty much did that - given the price of Europas in 1980 - and what I paid for my motor. But I had ended up with a head and a set of Dellortos so having a motor built with it seemed like the obvious thing to do. Also, it's a very straightforward engine swap that even I could do.

Offline Grumblebuns

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Re: Timing the twin cam
« Reply #19 on: Thursday,February 12, 2015, 11:57:12 AM »
Spent the morning getting close and personal with the TCS determining it's static timing. Following the directions of TCS4605R (Tom), I found my static timing to be 20 deg TDC. Through trial and error, moving the car back and forth while incrementally advancing the distributor got the static timing to 5 deg TDC as per the manual.

I was wondering if initially setting the timing marks at the flywheel to 5 deg TDC, then advancing the distributor to get the test light to light up would accomplish the same thing.

Second question, is finding the static timing point even necessary if the end goal is to set dynamic timing with the engine running?

The end result of finding the static timing point exercise is that I won't be afraid to pull the distributor out of the engine if I had to. Another kernel of knowledge in my personal knowledge base.

Joji Tokumoto   

Offline EuropaTC

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Re: Timing the twin cam
« Reply #20 on: Thursday,February 12, 2015, 01:23:33 PM »
Hi Joji,

Your first point - setting the flywheel then moving the distributor - well that's how I normally set static timing. I jack the wheel up and leave the car in gear because it's easier to move the wheel than a spanner on the front of the crankshaft. (which is what I do on the Elan, better access).

Then I remove the distributor cap so I can see the points, or in my current case the Pertronix, and move it so the light comes on. The reason I remove the cap is because once I set it on the "wrong" side of the cam - the points were closing not opening - and that didn't work so well. The other point is you're sure you have the rotor arm pointing at the right pole for #1 on the cap.

I've always used static timing and to be perfectly honest, when I check it with a light afterwards there's very little, if any, movement needed. Because I like to think of myself as a mechanic of course I always twiddle it a bit, but practically I think the car would run quite happily on the static settings.

Brian

Offline TCS4605R

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Re: Timing the twin cam
« Reply #21 on: Thursday,February 12, 2015, 09:53:37 PM »
BDA -  About ten years ago, I crewed for a Formula Atlantic Swift DB4 racing SCCA races.  At that time, a new engine cost about $25,000, a rebuild was $8,000 (built by Bruce Jennings on the West Coast of the USA).  They were fuel injected, developed around 240 HP and could run about 8 hours of track time before an engine rebuild was needed.  The rev limit was 10,800 RPM.  Very neat engine, so yours was a bargain.

What type of gearbox are you using with the Cosworth BDA and do you use the standard Lotus rear suspension?

Tom

Online BDA

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Re: Timing the twin cam
« Reply #22 on: Friday,February 13, 2015, 06:55:23 AM »
Tom,

Mine is certainly not a race engine - though it was balanced, blueprinted, ported, and dyno'd. Of course, mine uses Webers rather than injection. I'm not quite sure, but in our discussions, I thought Dave mentioned that mine was a "small valve" head it came off an Escort). I don't know if there were two versions of the head or opening up the valves was part of the preparation for the race motors. You might know more of the particulars about that.

I elected to use a cast crank. Dave offered a steel one to me for an additional $500 but I declined. Who would do a stupid thing like that? Well, it was 10% of the cost of the engine and Dave said it would only give me 1000 rpm. I don't think it was a race crank because I knew Atlantic drivers who twisted their motors to 9500. Dave said to keep the redline at 7500 and I thought that was plenty for a street engine. As for the price, keep in mind all this happened thirty five years ago!

Jennings has (or had) been building great motors for a long time, but my buddies who raced Atlantic generally used Grimaldi. Eight hours doesn't seem like much, but at almost 11000 rpm, I guess that's to be expected.

I'm using an NG-3 gearbox and Richard's twin link rear suspension with his rear disc brake kit.

Offline Grumblebuns

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Re: Timing the twin cam
« Reply #23 on: Friday,February 13, 2015, 07:34:15 AM »
Hi Joji,

Your first point - setting the flywheel then moving the distributor - well that's how I normally set static timing. I jack the wheel up and leave the car in gear because it's easier to move the wheel than a spanner on the front of the crankshaft. (which is what I do on the Elan, better access).

Then I remove the distributor cap so I can see the points, or in my current case the Pertronix, and move it so the light comes on. The reason I remove the cap is because once I set it on the "wrong" side of the cam - the points were closing not opening - and that didn't work so well. The other point is you're sure you have the rotor arm pointing at the right pole for #1 on the cap.

I've always used static timing and to be perfectly honest, when I check it with a light afterwards there's very little, if any, movement needed. Because I like to think of myself as a mechanic of course I always twiddle it a bit, but practically I think the car would run quite happily on the static settings.

Brian

Thanks Brian, pushing the car back and forth wasn't too bad of an ordeal but I thought there may be a better way. I haven't started up the car since I set the static timing and plan on doing another road test once the weather cools down a bit. We've been above 80 deg F for the last couple of days.

Joji Tokumoto