1970 R 1600, setting timing. do i try to achieve book spec's or give it more/less timing?

[Mspencer]

only have had the car for a few weeks, and cleaning it up while waiting for parts. replaced the starter, the plugs, cap and rotor. the car starts right up, don't need to give it any gas but the idle is at 1800 rpm so after it warmed up i adjusted the Idle so now its between 950 and 1k. the timing shows 16 at 600. that idle seems low but i will give it shot, any guidance here is appreciated. the timing marks are interesting, as i understand it, the center mark is TDC and the other marks are 5 degrees 

 

thank you.

[datzenmike]

The total advance, initial and mechanical should not total much more than about 32 degrees when revved up. The mechanical advance is built into the distributor, and on the '70 L16 should be about 22 to 26 degrees. If the idle is at 600 (a good number, 750 is what I shoot for BTW) then the initial timing should be more like 5 degrees BTDC.

 

I don't have the timing spec for the 510 but the L16 in the '73 truck is 5. The engine will start very well with 16 but when revved up the mechanical advance will add about 26 degrees for a total of over 40!!! The engine will ping and act up. 

 

Find the stock timing for your '70 and set to that. (I think 5 to 8 BTDC but check)

 

 

 

Once warmed up take the top off the air filter and make sure the choke is completely off or the choke flap is vertical. 

[MikeRL411]

Roadster not 510 !  Type R 1600cc engine not L1600.

[Mspencer]

17 minutes ago, MikeRL411 said:

Roadster not 510 !  Type R 1600cc engine not L1600.

Correct R 1600.

[datzenmike]

Profile and other post corrected to show R 1600.

 

Still 16 BTDC seems way too high for static timing . Find out what timing is and turn it down.

[banzai510(hainz)]

Is this a dual carbed motor? SUs Roadster?

I know On a 510 with dual SUs it was like 14btdc  at idle whatever idle is speced for.

You sure you got the right setting if you have one of those fancy timing light(dial it in) or just the point and shoot type.

 

vac advance hose hooked up to the right spot?

photos??????

Edited October 29, 2021 by banzai510(hainz)

[Mspencer]

On 10/29/2021 at 12:01 PM, banzai510(hainz) said:

Is this a dual carbed motor? SUs Roadster?

I know On a 510 with dual SUs it was like 14btdc  at idle whatever idle is speced for.

You sure you got the right setting if you have one of those fancy timing light(dial it in) or just the point and shoot type.

 

vac advance hose hooked up to the right spot?

photos??????

 

[stevecar]

You need to see if you still have the smog distributor. If so, the timing would be 0btdc. 16 is for non smog.

[datzenmike]

stevecar I thought there were only R1600 and R2000 cc displacements for the Roadster.

 

 

[stevecar]

11 hours ago, datzenmike said:

stevecar I thought there were only R1600 and R2000 cc displacements for the Roadster.

 

 

The Roadsters have 3 different displacements. The 63-65 SPL-310 1500 with the G engine, the 65-70 SPL-311 1600 with the R engine, and the 67.5-70 SRL-311 2000 with the U engine. The smog distributor was installed in the cars sold in U.S. 68-70.

Edited December 10, 2021 by stevecar

[datzenmike]

Ah. My limited info only goes back to '65. 

 

How is it possible to have 15 degrees BTDC on them? It's been my experience that the higher the compression the less advance.

[stevecar]

8 hours ago, datzenmike said:

How is it possible to have 15 degrees BTDC on them? It's been my experience that the higher the compression the less advance.

The pre-smog distributor cam will provide 15 deg mechanical advance, but the smog cam provides 35 deg.

If MSpencer set his initial advance at 16 deg and still has the smog cam, he would have about 51 deg advance with max rpm verses about 31 deg with the pre-smog.

[Mspencer]

24 minutes ago, stevecar said:

The pre-smog distributor cam will provide 15 deg mechanical advance, but the smog cam provides 35 deg.

If MSpencer set his initial advance at 16 deg and still has the smog cam, he would have about 51 deg advance with max rpm verses about 31 deg with the pre-smog.

[stevecar]

You cannot tell by looking at the outside of the distributor whether it is smog or pre-smog. You will have to see if the cam is 7.5(pre-smog) or 17.5(smog). It will be stamped on the top. Sometimes you can see it if you look through a hole on the plate at just the right angle, but usually have to pop off the plate to see it.