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Discussion Starter · #1 ·
I talked with my cam manufac to ask question about when timing should be ocoming in on my application and I believe he said around 2500-3000 all in. I told him, right now I am all in at 1900-2000. He said if it's not pinging (which it's not) then I should be ok with it coming in a little early. My mechanic who fired the motor and set the timing thinks it's too soon and will hurt gas mileage. My cam grinder said I should have a lot of low end torque (which I do) with it coming in earlier.

Ideally, who is right. Where do I want my advance coming in at. My mechanic recommended I get a new dist. (GM HEI said good enough). Said either my current set up the springs are badly worn or weights.. but something was off with it. It had a wire on the inside that caused it not to start initially as well. Can someone recommend a good street distributor for a stock 357 with Vortec heads 10.1 compression.
 

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Evil Wicked Mean And Nasty
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MSD Pro billit with a 6al box . Thats what i run and have had no issues . you can buy a complete kit but they are not cheap. So i guess it really depends on how much you want to spend. Last time i checked the pro billit with the box was around $600 but you get everything wires cap button all to install . JMO. Cole
 

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Well to start off with you can get a good Hei from summit racing for around $90 bucks I do believe and they come with a nice high output coil and they come with medium advance springs. They should work reall well for a good street performance motor. There is also Skip white on ebay who has hei's for around $ 55 or so shipped and they look really well but I have no experience with them but they give you a few years warranty and I have read on here to where some had excellent results with them. Get a hei recurve kit from summit or advance autoparts or napa or autozone if you have one near buy, if you get one it should give you a graph that shows you when your timing comes in at with the different set of springs.
Eric
 

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Evil Wicked Mean And Nasty
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eric32 said:
Well to start off with you can get a good Hei from summit racing for around $90 bucks I do believe and they come with a nice high output coil and they come with medium advance springs. They should work reall well for a good street performance motor. There is also Skip white on ebay who has hei's for around $ 55 or so shipped and they look really well but I have no experience with them but they give you a few years warranty and I have read on here to where some had excellent results with them. Get a hei recurve kit from summit or advance autoparts or napa or autozone if you have one near buy, if you get one it should give you a graph that shows you when your timing comes in at with the different set of springs.
Eric
I totaly agree with eric. Jegs has one also i ran in a stock 350 before i did the 408 thing. Cost was like around $100 or so, and it worked really well for the street. Cole
 

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Discussion Starter · #5 ·
$600 or so is getting out of the range and may be overkill. If I would have built a 383 or larger then that's a different story. I am slightly above stock with my build and would like ignition to be a step slightly beyond stock as well. The whole system has to compliment each other. In other words, what advantage does such a dist. ($6oo-) have over a cheaper unit at this level. I am interested in tuning.. and I think dist. selection is key.

My mechanic recommended a new stock/factory GM hei type unit and order a spring kit as suggested.. and play around with it this way. If I wanted the unit slightly above stock performance wise.. and did not want to fool around with anything inside, then which is the dist. for me. I really just want to drop it, wire it, and fire it. What's the rpm limit on stock gm hei.
 

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Evil Wicked Mean And Nasty
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Carlos9 said:
$600 or so is getting out of the range and may be overkill. If I would have built a 383 or larger then that's a different story. I am slightly above stock with my build and would like ignition to be a step slightly beyond stock as well. The whole system has to compliment each other. In other words, what advantage does such a dist. ($6oo-) have over a cheaper unit at this level. I am interested in tuning.. and I think dist. selection is key.

My mechanic recommended a new stock/factory GM hei type unit and order a spring kit as suggested.. and play around with it this way. If I wanted the unit slightly above stock performance wise.. and did not want to fool around with anything inside, then which is the dist. for me. I really just want to drop it, wire it, and fire it. What's the rpm limit on stock gm hei.
Thats what i did with mine, droped it in wired it up set the curve,havent done anything else before i was running a stock GM HEI and it was fine till i started getting in it up in the RPMs then it would fall off just loose it not anymore. But like eric said you can take a cheaper HEI and play around with for alot less money get some decent performance out of it. Cole
 

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Discussion Starter · #10 ·
eloc431962 said:
Thats what i did with mine, droped it in wired it up set the curve,havent done anything else before i was running a stock GM HEI and it was fine till i started getting in it up in the RPMs then it would fall off just loose it not anymore. But like eric said you can take a cheaper HEI and play around with for alot less money get some decent performance out of it. Cole
Cole, this is what I was eluding to when I mentioned I wanted something a little better than stock.
 

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If you want something more then stock then get either a summit gm hei or a jegs hei. They are both around $90 dollars or so and get a recurve kit. All you would have to do is change the springs and play with that nothing else. I have a aftermarket hei and all I did was go to autozone and got a mr gasket recurve kit and put the lightest springs on readjusted my timing and had to do nothing else. With the lighest springs all of my mechanical timing comes in by 3000 to 3200 rpm. Don't use the weights from Mr gasket they are junk. I just kept my ones that came with the distributor.is the one I have in my 96 s10 and I am getting ready to put in a new 350 and this is what I have from summit http://www.summitracing.com/parts/SUM-850001R/ then get a recurve kit from summit to go with it. http://www.summitracing.com/parts/SUM-G5212/ that kit has all the springs to recurve the hei to what you want. I would go with that. There is no need to get a MSD for a mild street engine. I have a 460 plus hp 350 in my other older s10 with big flowing heads cam etc and I only have a hei with a 50,000 bolt coil and a set of light springs on it nothing else and it works excellent.
I hope that helps out.
 

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Discussion Starter · #12 ·
ok, my springs (which are light also) must be worn or something else for me to be all in by 1900. Is there such a spring that would have that.. and maybe that's what I have. Not sure. If the summit brand already comes with a med spring (which is what I thought you wanted) then why change to a lighter spring.
 

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Evil Wicked Mean And Nasty
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The lighter springs like the heavier weights bring the curve in quicker. That why people change to lighter springs. Carlos i am not telling you to go buy a MSD setup, i know people that are running the same setup eric is running in his stuff and they dont have any problems i know of and the run on the street and the strip. I do know one thing like a good set of heads and a good carb and among other parts the distributer and the other parts all are investments to me,JMO What are your plans down the road with this engine? Cole
 

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Discussion Starter · #14 ·
My plan down the road are to leave it as it is. I only want to tune it to get it running optimal. I planned this build and have no future adders to it. Just want it firing good and hard on all 8 now with the right timing/adsvance etc.
 

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Carlos9 said:
I talked with my cam manufac to ask question about when timing should be ocoming in on my application and I believe he said around 2500-3000 all in. I told him, right now I am all in at 1900-2000. He said if it's not pinging (which it's not) then I should be ok with it coming in a little early. My mechanic who fired the motor and set the timing thinks it's too soon and will hurt gas mileage. My cam grinder said I should have a lot of low end torque (which I do) with it coming in earlier.

Ideally, who is right. Where do I want my advance coming in at. My mechanic recommended I get a new dist. (GM HEI said good enough). Said either my current set up the springs are badly worn or weights.. but something was off with it. It had a wire on the inside that caused it not to start initially as well. Can someone recommend a good street distributor for a stock 357 with Vortec heads 10.1 compression.
As to where you want your advance to come in at; the mechanical advance will begin to come in at around 800 RPM and continue until the advance weights are fully extended. The RPM where that occurs is dependent on what combination of return springs and/or weights are used and if you have limited the travel of the weights.

If your primary concern is the RPM that all the mechanical timing is in at; then you only need to swap the light return springs you are using for a heavier set. Usually one light and one medium spring will get the total mechanical timing all in around 2500 RPM for a GM HEI. For best street performance the all around favorite recommendation for the RPM to achieve total mechanical timing is in the 2500-3000 RPM. This really depends on your driving style and average cruising speed.

A cheap replacement HEI (like the one sold by Skip White) can be substituted. I have run one of the ones he sells and it works fine for street use. I did swap out the return springs as I mention above.

The stock GM HEI is a better alternative for street use.

While the MSD setup is excellent, it is way overkill (in my opinion) for street use and very high dollar. I'd consider it IF I were running at the dragstrip OR was running more than a 125 HP shot of NOS where a retarded ignition is required.
 

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Discussion Starter · #16 ·
Yeah, I was just trying to find out where it should be coming in. I have a buddy that races cars and he said his comes in at 2400. Not sure if it was circle track or bracket racing. He does both.

Anyway, when he mentioned I would have poor gas mileage (mainly because I was all in at 1900) this was when I started to want to investigate this matter. I do want to upgrade my distributor. Maybe the summit one or a stock GM replacement would fit the bill.

I was also a little concerned about the cam guy stating 1900 was ok if it;'s not pinging. He also did not think it would hurt gas mileage much. Who's right here.
 

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Carlos9 said:
Yeah, I was just trying to find out where it should be coming in. I have a buddy that races cars and he said his comes in at 2400. Not sure if it was circle track or bracket racing. He does both.
As I previously posted, the mechanical advance will begin to "come in at" around 800 RPM and continues to increase until the counterweights are fully extended. The RPM that occurs at is determined by the weights/spring combination.

Carlos9 said:
Anyway, when he mentioned I would have poor gas mileage (mainly because I was all in at 1900) this was when I started to want to investigate this matter. I do want to upgrade my distributor. Maybe the summit one or a stock GM replacement would fit the bill.
A stock GM HEI is not an upgrade but rather a replacement. This would also be so with almost any "stock" style aftermarket replacement HEI distributors.

Carlos9 said:
I was also a little concerned about the cam guy stating 1900 was ok if it;'s not pinging. He also did not think it would hurt gas mileage much. Who's right here.
It's not so much who's right, but rather what your overall performance is with the present timing. Having the curve extended so that it doesn't reach the full mechanical advance until a higher RPM than what you have at the present, should increase your overall performance as well as mileage. Extending the curve above 3000 RPM for a street engine is also not beneficial. Think about what the RPM is when cruising. Many vehicles are cruising at 60 MPH around 2200-2800 RPM. This all depends on the gearing and tire diameter. For best overall fuel mileage, that is where the total mechanical timing should be. The actual total timing at cruise speeds will be higher if vacuum advance is also hooked up. This will further increase fuel mileage.
 

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First off, find a new mechanic. Secondly, buy a curve kit for the dist you have (about 10 bux) and follow the instructions. Start the advance at about 800 or so and max it by 2800. Problem solved. NO, you will NOT have bad gas mileage with it all in by 1900.
 

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Discussion Starter · #19 ·
Before we go knocking the mechanic, let me tell you it is not him.. it's totally me in this scenario. This guy knows his stuff. He may not have the time to explain it to me completely, but I did pick-up that there was a problem with it coming in early. That's all I needed to know. He just felt that this was something that's worthwhile for me to learn if I'm going to be tuning my cars. He was obviously there, so he saw the truck, tire size, output from the motor from firing it/breaking in the cam, putting it on his light, adjusting timing. idle speed, etc.. so this was his assupmtion of it all. All he was mentioning was once I get the advance set where it should be and timing everything straightened out that it would run even better than it does now.

It amazes me how people start pointing fingers. It's me idiot.. not him. This is why I am on here asking.

For the sensitive on word guy, when I said upgrade, even "A stock GM HEI" is an upgrade compared to the POS unit I have now.
 

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Any aftermarket hei will be an upgrade in my opinion. I had a stock reman hei from the autoparts store and it was fine till I ran the rpm's above 4500 plus. The original stuff just did not do much. Replacing the springs and weights along with a bigger coil and control modual from proform it brought the thing to life. If you get one from summit its not a stocker hei by any means. The stock ones come with a 35000 volt coil and nothing fancy and stiff springs and does not bring totatl timing until around 5000 rpm. The summit ones come with a set of medium springs and a high performance control modual and a 50,000 volt coil and a good cap and rotor. That will be a difference then an old stock one. If I was you get the one from either summit or jegs and get a recurve kit along with it and you can get everything you need.

I am running mine still in a 350 with all kinds of high performance aftermarket stuff and my hei works awesome. Has no problem going to 6000 rpm.
Eric
 
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