I ordered bigslantsixfan's spring kit and it came in the other day. But I haven't been able to figure out which curve would be best for my setup.

Setup this is going on: stock bore, 8.8-9.0 comp, aussiespeed hurricane w/ 350, OCG819, 108lsa, ground w/ 4* advance. Stock stall 904, 2.76 gears, full street weight dart sport.

I have two governors, a 13R (.477) and an unmarked one, that mics at .380ish.

I've read that you don't want a real fast advance on the street with high gears. Why? What falls under "real fast advance"? Would a blue and yellow spring be alright? The kit recommends the .380 slot, but I thought I'd seen the 13R recommended as well somewhere...

I just need some good input and understanding on the matter I suppose...

I'm doing recurving on my 225 now with bigslant6fan spring kit. Have exactly the same specs like you except I have 2bbl super six setup, a stock cam and stock compression on my 70 Valiant. What I have done was to check how much my rpm are at various speed to know which curve suited me best. I drive really slow max 50 mph and that's 2000 rpm on my gauge. So I wanted a curve that maxed mechanical before or at 2000 rpm to utilize the advance for good mpg. For now I'm using yellow and blue spring 12 initial and 17 mechanical which gives me 29 total. You want 30-32 crank degrees initial timing + mechanical for good performance. If you then use the 0.380" (17 crank degrees) governor which I run you can run 13-15 initial timing. If you run the 13R governor you then have 26 crank degrees mechanical then you would have to run 4-6 intial timing which are to low in my opinion. I have tested blue and green which were to slow for my liking but real close to a overall ideal advance curve I think. Have tested blue and blue which are better on the lower rpm. The yellow and blue are probably the fastest advance curve you will run on the street I think. The best thing is to have patience and try diffrent spring setup the feel which one suits you best. The slower the curve I have run the better the acceleration is at a higher speed and the faster the curve is the faster it is at lower speeds in my experience. What are the goals for the recurve, better mpg, WOT performance or a combination? You have the vacuum advance also to deal with. I wanted 52-55 degrees total plus vacuum advance for best mpg. I run a vaccum can from a 318 which is stamped with only a 12 on the arm which are 24 crank degrees. So with my 29 total and 24 vacuum advance I get 53 degrees total + vacuum. My mpg now are 25 which I'm real happy with. I'm a novice in this but this is my experince. AggresiveTed on this board have alot more experince and have helped me alot. Take some notes to know what you have done. Good luck and have fun.

Oh yes, I forgot to mention my vacuum can. I don't have it in front of me, nor recollect the part number, but it is stamped 11 on the arm.

Also, thanks for mentioning goals as well. I'm going for a rather peppy motor, but don't plan on going past 5k with it, going for lots of torque. I would also like to get pretty decent mileage out of it as well, expecting at least 20mpg, with 25+ being the ultimate goal. (Aerodynamic tricks, like Sam Powell conducted a study on months back, will be imitated to reach this. Also, manifold heat of some sort would help dramatically I'm sure.) Also, I hadn't thought of a fast advance hindering my higher speed acceleration (I'm thinking, freeway passing type situations, correct?)

Thank you for your input!

When accelerating vacuum will drop off depending on how much throttle opening, and it can come close to zero at WOT uphill. When this happens, the additional vacuum advance falls off to zero that would have been added to mechanical. At this point rpm controls any mechanical advance until it is maxed out at say 2500 to 2800 rpm. giving around 30 degrees of advance or so depending on your curve.

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82' LeBaron Convertible; the new Chrysler Corp
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