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Bills R2
11-11-2006, 12:08 AM
What seems to be the modern(1/2R+M) fuel requirements for a stock R2 engine? I don't know if compression has been lowered and I hope it has hardened seats.It seems to have been camed,perhaps with an R3 cam?Does anyone know the timing specs for that stick? The engine seems to want more initial timing but it already pings with 91 octane.
The book says my dizzy should have 18 mechanical degrees but it looks more like 24.

'64 R2 back on da road again
POCI,SCCA,SIMTA

GTtim
11-11-2006, 12:32 AM
I've been experimenting with tuning my R2 all summer. Most people that I talk to run their R2s at 28 to 32 degrees total advance. Have you checked the distributor to see if it is the right one? The Prestolite distributors are also famous for problems when they are worn, which can be anytime after 50k. I still get a little ping at 30 degrees total and 93 octane.

Tim K.
'64 R2 GT Hawk

PackardV8
11-11-2006, 04:46 PM
FWIW, if you, in fact, have an R3 cam, it will lower the octane requirement, because the later intake closing lowers the effective compression and will need more low speed ignition advance than the R2 spec calls for.

Second the suggestion you might want to think about your distributor. The Prestolite is always suspect and it really has no place on a current performance driven Avanti. The real answer is to call Dave Thibault and order one of his new Mallory billet units with an R2 or R3 curve built in. If you plan to enter it in concours judging, paint it black and get a black distributor cap. Under the Avanti shielding, no one will know the difference.

thnx, jv.

thnx, jv.

PackardV8

Bills R2
11-12-2006, 11:00 PM
Checking the bushings is a great idea. The dwell does hold steady as a rock though...If the points weren't new,it would already have pertronics! Maybe the cam is wiped out? Got a hundred miles on her now and it runs like cr**!:(

'64 R2 back on da road again
POCI,SCCA,SIMTA

1956 Hawk
11-13-2006, 01:26 PM
I have been working on this for the last 6 months. 91 octane will work fine if the engine is tuned correctly. Like Tim said 28 to 32 degrees should be just fine, but the car will idle much better with more inital advance. Have you tried tuning the carb. If it goes just a little lean it will ping like crazy. Try richening the jets and see if that helps.
David

GTtim
11-13-2006, 11:08 PM
Bill,
Check the numbers on the distributor to make sure it is an R2 type. The R1's have a little more advance in them. Also the cams that do the advancing wear and allow things to get out of spec. Take the distributor out and give it a thorough checking out.

Tim K.
'64 R2 GT Hawk

Bills R2
11-14-2006, 08:49 PM
Iv'e got a dead hole on number 6...I'm going to yank the chrome thingy tomorrow and see if the rockermabobs go up and down.
I'll keep ya posted!

'64 R2 back on da road again
POCI,SCCA,SIMTA

Bills R2
03-13-2007, 11:22 PM
I can't believe it has been 4 months since I popped the hood![?]
Made it out to the garage as it was 70 today!!
Couldn't find any reason for the mis, so I checked valve lash and the valves were pretty tight. I loosened them up a bunch,the book says .030 cold and I will fire 'er up wed and see what happens.

'64 R2 back on da road again
POCI,SCCA,SIMTA

bige
03-14-2007, 08:25 AM
I think the key to properly timing the R2 is making sure the total mechanical advance is all in at 24-28 at the 1600 RPM the factory specifies. I've literally spent years playing around with the timing on my R2. It has a Delco window that I had to alter to match the curve of the original Prestolite. I've found that my car runs the best at around 26 Total. Yes, it will feel more powerful down low with more initial advance but doesn't build power in the upper ranges as it should until it gets backed down to below 30. Each car is different and mine has had internal and external mods but I believe the fast mechanical curve was put there to aid low rpm power without having too much at full boost. You're getting plenty of advance just off idle but nothing further.

Check for intake manifold to head leaks. Brand new metal gaskets never sealed as they should on my car and I was trying to tune around vacuum leaks for months. The fiber gaskets with new intake hold downs ( found some cracks in a few of the originals ) cured the weird idle problem.

You mentioned 91 octane, is there 93 available in your area? You may be trying to tune around an octane deficiency.

Last but not least, when does it ping? A part throttle ping may be the result of too much vacuum advance. Try the car with the vacuum hose off. The whole process is a balancing act. At part throttle under load if the vacuum advance is adding too much any static changes to compensate will hurt performance.

BTW, the 18 mechanical is added to the static timing so you're in spec at 24 total advance. 18 mechanical plus six at the crank.

ErnieR

http://i146.photobucket.com/albums/r241/AvantiR2/avnatiglamour007.jpg

JDP
03-14-2007, 10:51 AM
If you ar not careful, you can hole a piston with too low a octane under boast. You won't hear the detonation at high RPM under boost, but it'll be there even with 93 octane if driven hard. If you baby the car. you'll be fine, but what's the fun in that ?:)

64 Commander 2 dr.
64 GT Hawk R2 clone
64 Daytona HT
63 Cruiser
63 R2 4 speed GT Hawk (Black)
63 Avanti R1
63 Daytona convert
63 Lark 2 door
63 Lark 2 door #2
62 Daytona HT/ 4 speed
62 Lark 2 door
60 Lark HT
60 Hawk
59 3E truck
52 Starliner
51 Commander

Bills R2
03-15-2007, 11:43 PM
Boy,does she run GREAT! Loosening up those valves made all the difference. Nice idle,lots of tire noise... I do have a little valve train noise now,I may take up a little lash. How little clearence can I run,setting them cold?
And thanks to all for your advise![8D]

'64 R2 back on da road again
POCI,SCCA,SIMTA

PackardV8
03-16-2007, 04:30 PM
Hi, Bill,

Glad you are getting what you want from the engine now. IIRC, you aren't completely sure which camshaft you have in your engine. therefore, it is tough to give an informed recommendation.

Some time back, I got a tutorial on valve clearances from Ed Iskenderian himself. He says, in effect, valve lash is negotiable. If you want less noise, a bit tighter will give less noise, but also less low end power and a rougher idle. Loosen a bit to add low end power and smooth the idle, at the expense of a bit more noise.

I used to get all scientific, using a dial indicator to get each one exactly the same, but he just laughed at that. If it takes a couple of thou less to quiet one particular valve, don't worry about it.

thnx, jv.

PackardV8