scooter123

My balancer Is bang on the mark......I checked it using a dial indicator when the heads were off at TDC on the # 1

I will try to fine someone around town that knows distributors and give me a hand with it!!! There is a older guy in town that builds engines but has retired!!! We will see

Thanks guys!!

captjim

THe problem is you suggested that a larger carb will reduce the detonation, which is ridiculous. At part throttle, carb size is not the issue, maybe jetting.

Scooter, just looked up cam specs, .475/.480 and 218/224 is a pretty small cam for a 10 to 1 468. Do you know if it was degreed? 160 cranking psi does look good, though.

coppercutlass

Jim i did not say his carb was the issue ., again you assumed. He did say however that his previous engine seemed to have more power. An under carbed engine will not make good power. Also doesn't detoation usually happen under load. Why would part throttle have anything to do with this he said his engine seems under powered so he obviously wants to get on it a little bit so a 650 carb is kinda small to smoke the hides. Also did you not read marks post where he mentioned his true compression could be lower.

442rocketdave

By the chart your 461 cubic inch motor with at least 9.6 compression at 5200rpm needs 738cfm at 5500 778 and at 5800 800+ so a 750 is in order and it will run better! Hopefully the problem lies in the distributor with the advance mechanism since the balancer is ok I would guess the distributor is where the monkey wrench is.

captjim

I agree, as do others.

Copper, detonation will happen under part throttle if the vacuum advance is adding too much. The factory has a specific "curve" with initial, vacuum, and mechanical advance. This "recipe" is designed for a specific engine combination. Change the combination (cam, compression, etc) and the timing curve needs to be changed, too. At part throttle, you have both rpm resulting in some mechanical advance and high vacuum resulting to a lot of vacuum advance. Combined, it can be too much which is why Oldcutlass suggested disconnecting it.

BTW Scooter, just curious, are you running headers?

coppercutlass

Yes and oldcutlass brought up a good point in disconnecting it. I know how detonation happens. I have chased my share of timing gremlins. What i was getting at and you mentioned it that at part throttle carb size does not matter and he mentioned he wants it to make some power. So keeping his carb would not make sense if he wants to smoke the hides like i mentioned. I never said his carb size was the issue just that he should probably get a bigger one. Again you keep saying i say things i dont.

scooter123

Its all good guys...I will get things all sorted out here in the next little bit.....please do go off the head with each other.....between all the knowledge here we can get it done in a positive manner!!

Thanks!

captjim

He made a suggestion that I and Mark disagreed with, that's all.
So, are you running headers? Also, is it the original points distributor?

scooter123

stock headers and I have a petronix ignition and msd coil and msd 8.5 mm wires

captjim

You made a post suggesting a larger carb right in the middle of a thread where detonation is the issue. Your posts are often incomplete and hasty; this has been brought to your attention many times. It is not our fault that we don't undertsand what you mean. Take a moment to make a concise, coherent post.
Also, you stated this,
"Also doesn't detoation usually happen under load."
If you truly understand the role of all the components and how they work together, you would not have made that statement. Detonation happens at part throttle as often or more so than at WOT.

coppercutlass

yet you say at crusing rpm carb size does not matter yet i doubt he will only be crusing it. Then mark tells him to re jet it !!!!!! You guys cant be serious about telling him to keep his carb. Im sorry But out of all people you guys arent telling someone to go to a bigger carb when i got a ton of crap for running a 600 eddy carb on my last 350 and everyone saying it needs a 750. You have a 770 on your 355 correct ? there is a reason for that. I see him having too small of a carb as an issue maybe not with his detonation but once he gets his timing sorted out and he actually wants to get on it that 650 wont do much.

captjim

OK, is the Petronix and HEI replacement? By "stock" headers do you mean the factory exhaust manifolds?

Edit: Is this it?
http://www.summitracing.com/parts/pn...ake/oldsmobile

If so, there is your lack of grunt. These are HEI units, they like a lot if initial.

coppercutlass

Jim i have only experience detonation once and it was under heavy load wot. I took care of that. Also if you pay attention someone before i did suggested he get a bigger carb. Wouldnt you say something if you saw something wrong or could help. It seems like you guys do it all the time. All i did was make a simple statement and you guys run with it and thrash me. Well you too jim can do everything i told mark to do.

captjim

Then state "While I do not think it is a factor in your engine detonating, I do think it would benefit from a larger carb" See, not so difficult.

scooter123

yip factory exhaust manifolds.... petronix is electronic ignition ..if thats what your asking!!

coppercutlass

jim only you, mark and nick seem to have an issue with what i post or what i say . Only you guys., you do realize this correct ? no one else has an issue with what i say or suggest. No one else reads into whats there they take it fwiw. For instance A post came up and the op. asked about using 14cc pistons and balancing and you said it shouldnt be an issue. yet i got flack from you and mark and i forgot who else for not balancing my frankesntine 350 with cast o.e. flat tops. Which why would you suggest someone re use stock pistons when you guys see it as a cost effective replacement when i did that i got crap. sorry scooter unfortunantly i cant post or suggest anything on anyones post without the same clowns doing the same things and complaining about the same crap.

captjim

Yes, but does it have the big cap? Is it the one I posted above? If so, this is a major issue. You stock timing specs are for a points dist. HEIs like a lot of initial, this is probably why it is sluggish off the line. Here is my HEI "recipe". Get a set of timing springs. They came in three pais, light, medium, and heavy. Use 1 light and 1 medium spring. Set initial at 22 degrees with the vac disconnected. Connect vac to manifiold and see how much it adds. That dist should have an adjustable can, it requires a small Allen wrench. Adjust it until you get 10 degrees of vac advance. Take it out and drive it. This combo has worked very well for me on 355s.

scooter123

no its not that one ...it has a regular cap....cant get my photo of it on photobucket right now

captjim

OK, then disregard the HEI part.

oldcutlass

3 things:

Jim, Copper>>>>>to your corners, you guys are in time out. Joking!

The carb question came up during his build post and I believe this engine was originally a low comp 2v.

The timing was supposed to be set to around 34 initial+mech @ 3500 RPM with vacuum advance disconnected.

I'm wondering if with the vacuum advance disconnected are we still getting detonation? If we are then the timing is probably coming in too fast.

scooter123

I drove it to work this morning...11km with it disconnected and pluged and it was bad

oldcutlass

Was this distributor on the car with the old engine? And you have 12v to the coil?

scooter123

Ya its the same distributor as the old engine.....I will have to check the voltage to the coil

As for recurving the distributor......Is there a kit I need to buy...any recomendations??

oldcutlass

What was your engine doing with the vacuum advance disconnected? and prior to that was it hooked to manifold or ported vacuum?


Yes, there is a kit:

http://www.summitracing.com/parts/pn...1/applications

You also mentioned something earlier in the post about your balancer jumping around? Can you explain that part.

scooter123

I got 12.3 volts with the key on but the engin not running on the + side of the coil

oldcutlass

You really need to check this with the engine running, voltage at + side of coil and at battery +. Is there a tan, very stiff wire on the coil +?

442rocketdave

Hey Scooter any progress??

scooter123

i put the new carb on tonight.....And cant say I notice much difference in power...but it fixed my lean problem.....plugs are now I nice tan colour now!!

As for working on the distributor...I ordered a spring kit/weights.....I still have to ask around to find someone to give me a lesson in this area!!

Im going to contact the machine shop next week to see how much he removed off the heads and block.......I did not ask him if he could tell if it was blocked or decked before.....is there a way to tell???

Im starting to think this engine it higher compression than I think!!

Before I rebuilt this engine...stock....I could leve a strip of rubber about 50 ft long......not now.....something just not right....car runs/starts/idles grea tbut with this new cam and higher compression I was expecting a little more power from all the work I put in

oldcutlass

Once you get the timing right it probably will have more power. Be patient and don't hammer on it too much with the detonation.

442rocketdave

Be patient, the motor is not broke in and you have to get that timing right. The power will come!! when you get everything in sync then she will start to run especially when it is completley broke in. I have seen motors not break in for over 500 miles and some a 1000 miles.

scooter123

I hope so dave!! I just have to relax and take time to learn more and more each day!! I also backed the timing off to get rid of the engine ping!!

442rocketdave

Well one good thing is your plugs arent bone white and that nice tan color is a step in the right direction. Get that advance curve set right and get everything in sync and she will start running strong soon. Check out the products I told you about!

scooter123

yiper!!

cutlassefi

Here are some facts;

A carb that's "too small" should leave just as big of a burnout as the "right" carb. Where it will fall short will be in the upper rpm ranges. Put a vacuum gauge on it an you'll see what I mean, it'll start to pull vacuum at wot once you get to the higher rpm ranges but otherwise it will behave just like the "right" carb when you punch it initially. Jetting however needs to be optimized for any size carb.

Your timing mark moving around is obviously not from a loose balancer ring, as you've checked it correct?
It's the module in the distributor. I know there are a hundred guys on here that use the Pertronix stuff, but all the ones I've used did the same thing. An inferior/cheap module will not hold the timing steady, plain and simple. All that stuff is made abroad and some are better than others.

And if it's not broken in by now then you either have the wrong rings in it or the improper wall finish. Most ring sets today seat pretty quickly when everything is right. And yours being lean lends itself to quick break in vs too much fuel and possibly washing out the rings.

Where is the timing set now?

Thanks

442rocketdave

CutlassEFI is right on the money! I had an electronic conversion years ago and I had problems so I switched back to points and used the MSD 6a and used the points to trigger it and it worked fine. Also in the past many people used chrome rings and did not have the proper finish for them and it took forever to break in and that included standard rings also with poor honing jobs it would take longer.

coppercutlass

Mark you an I both know if he wants to make somepower the 650 will only feed it so much. Sure he could have jetted it and put time effort and money into fattening up the 650 but in the long run he would not have been happy as I thinkhe wants to get on it a litle bit. Also my experience with a small carb is much like scooters sort of. I ran a 1405 edy carb. The car ran 13.3's at 103 with it. But it would bearly spin the tires on the street. I put a holley 650 dp and it packed a much bigger punch. Then I added a better converter and things really go intresting. Both carbs ran great box stock the eddy was a tad bit lean the holley is on the money. Just my experience. I run a proform hei and I have been running it for years probably 6 now and no issues . In box stock form it worked very well. All I did was add a lighter spring and it has worked flawlessly. Mark it's. Kinda like the iron vs. Aluminum heads. I think spending money on the proper carb will be money well spent in the long run. Plus again like I mentioned I don't think you would recommend a 650 carb for someone who wants a little performance. What kind of speed shop do you run where you reccomend some one re jet a small carb when he will be money and time ahead buying the correct one that will feed his engine correctly.

MDchanic

This is a side point, but not off topic (perhaps a "low-jack" ) and generally FYI --

I have been tuning an engine which came with a points distributor and a Crane magnetic pickup unit.
I've never used a points-substitute before, and hadn't heard anything bad about them, so I kept it.
It seems to start and run well.

Most of the tune-up tachs I have used on this motor (yes, I tried a few, including a Snap-On MT460), have seemed to "conk out" and go to zero just before 3,500 RPM. I figured it was probably the result of the "computerized variable dwell angle" feature changing the pulse width to something the tach wasn't prepared for, but, still, it was weird.

Also, I had noticed occasional "jitterimess" to the timing mark, like it will hop 5° for the blink of an eye every now and then.
I had ASSumed that my timing lights (yes, two different dial-back lights, one a Snap-On, one cheap) were shaky, but maybe it was that darned module.

I'll keep an eye on it, and of course I have a set of pre-set-up Blue Streak points and condenser in the glove compartment.

- Eric

cutlassefi

But by the same token if he wants to get it running better with what he has then why wouldn't I recommend what to try next? Aren't you a big proponent of using the stuff that you have? Or have you changed your mind on that too.

I stand by my recommendation, and his response confirms that doesn't it;
"And can't say I noticed much difference in power". hmmm. Kinda my point huh.

Just sayin'

coppercutlass

I'm a fan of using what you got if it will run right. When my points distributor did not work I bought a hei, when I finally decided the eddy wasn't enough carb I bought one. The diffrence is I bought my carb through holley's ebay store very very cheap. And my hei I bought cost much less than a lot of the other ones. Putting a new carb may have not added a bigger punch but eventually when he gets on it it won't fall on it's face at certain rpm. That's what I'm geting at.

oldcutlass

IMHO he did not have a carb issue, it's timing. The advance kit Scooter ordered should correct this.