Locked Distributor for Strteet Use

[F-BIRD'88]

Thanks, going to try one out next opertunity.
Getting the PCV correct is important.
Sorry Dvance is advance (spelling) Thumbs are too big.
Or phone is too small...

[BBO Omega]

I locked the timing at 36 deg on my 468BBO in preparation of programming my MSD 6AL2. It ran so much better all around, that I never did program in a curve. Got rid of the stinky idle the car always had. This is a 11.59cr 468ci Olds that I regularly drive on the street but it is not stock. Engine starts without an issue with a factory HiTorque starter (without the brace).

[73c34me]

I have tried several curves with my MSD system. My 383 SBC , 11.5:1 w/ a 239 at .050 Straub camshaft manual transmission.
It runs the best with the distributor locked out at 35ish degrees and the vacuum can plugged into the full time manifold vacuum. The vacuum can is limited to 10 degrees additional timing. I wish I could set the idle timing set to achive 55-60 degrees! Then pull it back.

I am always curious as to why it is said that manual transmission cars like a "curve". This goes against everthing all my small block combos have experienced.

[groberts101]

I have tried several curves with my MSD system. My 383 SBC , 11.5:1 w/ a 239 at .050 Straub camshaft manual transmission.
It runs the best with the distributor locked out at 35ish degrees and the vacuum can plugged into the full time manifold vacuum. The vacuum can is limited to 10 degrees additional timing. I wish I could set the idle timing set to achive 55-60 degrees! Then pull it back.

I am always curious as to why it is said that manual transmission cars like a "curve". This goes against everthing all my small block combos have experienced.

You and BBomega, and probably most others who don't know programmable MSD boxes exist outside of EFI setups, don't know what you're missing out on! 7 series box is fantastic but even the 6 series is worth its weight in gold on a high compression street type deal. Motors feel much larger than they actually are during low rpm transitions and abrupt digs.

On my last 11.5:1 385sbc with programmable 6al I was at 54 degrees until about 1,700-1,800 rpm when the unit started ramping back timing to 36 under WOT. Anything else less than partial throttle and the map sensor allowed way more part throttle timing than most here would ever be comfortable with. Well.. at least those who haven't ever seen or programmed efi maps.

[groberts101]

I locked the timing at 36 deg on my 468BBO in preparation of programming my MSD 6AL2. It ran so much better all around, that I never did program in a curve. Got rid of the stinky idle the car always had. This is a 11.59cr 468ci Olds that I regularly drive on the street but it is not stock. Engine starts without an issue with a factory HiTorque starter (without the brace).

You're leaving tons of part throttle torque and efficiency on the table there. Get a gm map sensor and repin the msd's screwy pinout to match. Only reason they moved the pins is to get you to spend more cash on there "special" map sensor. GM stuff works just the same and you can run the vac hose under the dash to keep Installation cleaner.

And another fyi.. by default, that box has a 25 degree start retard built in.

[BBO Omega]

I do have a programmable MSD unit (6AL-2), and I’m sure I’m leaving some MPG on the table by not using a MAP sensor and programming in a “Vacuum Advance”. That said, unlike you small block guys, the taming down of low speed torque is a plus for my Omega with a 468 BBO on the street. It lights the tires at will already. With a 4200 Converter, the curve would have absolutely zero effect on my 1/8 or 1/4 mile times.

[73c34me]

I locked the timing at 36 deg on my 468BBO in preparation of programming my MSD 6AL2. It ran so much better all around, that I never did program in a curve. Got rid of the stinky idle the car always had. This is a 11.59cr 468ci Olds that I regularly drive on the street but it is not stock. Engine starts without an issue with a factory HiTorque starter (without the brace).

You're leaving tons of part throttle torque and efficiency on the table there. Get a gm map sensor and repin the msd's screwy pinout to match. Only reason they moved the pins is to get you to spend more cash on there "special" map sensor. GM stuff works just the same and you can run the vac hose under the dash to keep Installation cleaner.

And another fyi.. by default, that box has a 25 degree start retard built in.

Maybe. However my last curve was with an 8 degree bushing and stiff springs to bring the curve in fully after 3000 rpm. Locked out has better seat of the pants response.

[groberts101]

I do have a programmable MSD unit (6AL-2), and I’m sure I’m leaving some MPG on the table by not using a MAP sensor and programming in a “Vacuum Advance”. That said, unlike you small block guys, the taming down of low speed torque is a plus for my Omega with a 468 BBO on the street. It lights the tires at will already. With a 4200 Converter, the curve would have absolutely zero effect on my 1/8 or 1/4 mile times.

I kinda figured that.. almost added your likelihood of needing to control traction in my reply but kept it short for a change. My old classmate had a 455 powered omega too.. also knew many with 455 powered late 80's cutlasses as well(1 was even chained down!). They were mostly semi-rusted shitboxes with motor swaps but there was a couple solid running high 11 second cars with mild bolt-ons and gutted interiors that easily impressed back in those days.

I will say that you could easily use it as a traction control device with many different curves being set aside for varying track and pavement temps. Plus, I'd rather have my motors being all they can possibly be, highest possible cylinder pressure the fuel and acceleration rate will allow from idle to redline, and have to pedal it. Brackets would be a different beast of course and consistency is key there but I'm sure you catch my drift here.

[groberts101]

Maybe. However my last curve was with an 8 degree bushing and stiff springs to bring the curve in fully after 3000 rpm. Locked out has better seat of the pants response.

These boxes are set up with locked distributors and retard timing up to 25 degrees from your base timing settings. They work far beyond what any conventional centrifugal weighted/vac pot distributor will allow without having to rob peter just to pay paul. Having fine tuned the bejesus out of many conventional setups I will never go back after using programmable stuff. It really is that good and far faster to dial in.

[novadude]

The down sides are higher engine temps a cruse and maybe idle , greater fuel usage which tie's in with faster engine ware!
Here's what the tipical mid 1960's GM V8 Dizzy came set up for.

I like that curve. I've found that setting up the distributor that way works very well for street ~327-350 ci engines with 9:1-10:1 CR, and mild (<225@0.050") cams.

[GARY C]

Ever wonder why no one does a "Locked Fuel Curve"?

[427dart]

Car is fairly light weight .... under 2700 lbs with me in it and half tank of fuel , and a 5speed manual . Engine is a 482 FE with a BLP Billet 4150 mini annular carb on an Ebrock dual plane intake .
Been playing with springs on the MSD distributor ( no vacuum advance ) and beginning to wonder if I wouldn`t just be better off with the distributor locked out at 36 degrees .
What downsides for a street car/play toy would there be if I did that ? I`m thinking ( while having a brew or two ) if I take the two lightest MSD springs and stretch them slightly so at cranking speeds , I have zero centrifugal advance , but when the engine fires , it goes to full advance , 36 degrees , that should tell me how the car runs without pulling the dizzy to lock it .

Thoughts ?
BTW ... It runs on premium 91 pump gas .

I assume that 482 is in a Ford and at under 2700 lbs. what could it be? Cobra? Sounds like a beast!

[novadude]

Ever wonder why no one does a "Locked Fuel Curve"?

[Kirk600]

I have my MSD set up with 1 spring in it..... full advance happens around 2100rpm

[427dart]

I have my MSD set up with 1 spring in it..... full advance happens around 2100rpm

Same here but it's a ACCEL Billetech Race distrib with Crane Hi-6 unit...all no longer made since MSD bought out everybody.