340 stroker 422

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Sheeeeeet…. I just run as much advance as I can and then work the springs on the curve. You all know when you go to far with that right?

LOL!
 
BIIIIIIIIIIIIIIIIIIG mistake not using vac adv. Should be used, adjustable unit, connected to manifold vacuum.
I prefer ported vacuum, there is too much variance using full manifold vacuum.
It really raises hell off idle and transition in gear.
 
fishmen,
MVA works just fine when it is dialled in properly.......AND the correct VA can is used. A common problem is trying to make MVA work with a factory VA unit......& bigger cam with reduced vacuum.
 
Rat,
Post #119. To answer your question, yes. I have done it many times. 11.3:1 CR Pontiac engine, idled with 53*.
Factory Pontiacs with 10.75 :1 CR had 26* at idle with 198 @ 050 cam. Rembering that factories had to be conservative.
With higher CR, you may have to cut back on both the rate & total amount of MVA added. Sometimes slightly stronger springs are needed in the dist. It is all part of the tuning process.
It always amazes me that people buy a Holley or some 'upgraded' fancy looking clone & then f**k around for hours changing air bleeds, emulsion bleeds, etc....but never bother dialling in the idle ign timing that makes so much difference. I wish I had a dollar for every off idle hesitation I have fixed by merely giving the engine the idle timing it wants.
 
Heads are from 67 to 67.5cc.
They are bolted on, did some work today. Tomorrow will cut pushrods, put carb on it and wait till there is time to start this thing.
I have ngk bcp7es plugs, should I give them a shot or go to 8 from the start?

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Heads are from 67 to 67.5cc.
They are bolted on, did some work today. Tomorrow will cut pushrods, put carb on it and wait till there is time to start this thing.
I have ngk bcp7es plugs, should I give them a shot or go to 8 from the start?

View attachment 1716022075

What is your final compression ratio? If that plug is an extended tip there is no way I’d start with that. You need a standard reach plug. Start with that in an 8 heat range and tune from there.


One of the things with high CR pump gas engines is extended tip plugs. Sometimes you just can’t use them.

Which is why I said plug selection is critical.
 
What is your final compression ratio? If that plug is an extended tip there is no way I’d start with that. You need a standard reach plug. Start with that in an 8 heat range and tune from there.


One of the things with high CR pump gas engines is extended tip plugs. Sometimes you just can’t use them.

Which is why I said plug selection is critical.
Any suggestion from NGK?
 
Heads are from 67 to 67.5cc.
They are bolted on, did some work today. Tomorrow will cut pushrods, put carb on it and wait till there is time to start this thing.
I have ngk bcp7es plugs, should I give them a shot or go to 8 from the start?

View attachment 1716022075

What head gasket thickness?
Did you say the pistons were .010” down?
 
What head gasket thickness?
Did you say the pistons were .010” down?
0.039”

I bought cosmetic 0.065” as backup that will lower the compression to around 10.6:1 but want to try as is first.

Who knows.
 
I hate this intake. I think victor would be the best for this…
This engine will evolve with time for sure.
 
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I had a 360 with a similar set up for cam and heads.

A cleaned up victor was worth about 25HP up top but it paid the price down low. WAY behind the RPM and TQ crossover was about 5000rpm.
 
Yep, some don't get it: big cams & big intakes taketh from the bottom & putteth at the top.....
 
Guess it depends on what you are after. That 232* camshaft is almost a carbon copy of mine and it ran way better than anybody thought it would throughout the ranges with both manifolds. WAY BETTER.

My rig was 35HP better up top and from 4600 on it stretched out quickly. I looked at the sheets... I'll guess that stroker is going to be done with max HP around 5700 or so. Still going to be a solid runner with a good tune staying out of detonation.

Running a street car driving around town, I'd leave the RPM on that stroker, although, the arm would make a big difference in the lower end tq. Again, whatever you're after in the end.
 
I had a 360 with a similar set up for cam and heads.

A cleaned up
Guess it depends on what you are after. That 232* camshaft is almost a carbon copy of mine and it ran way better than anybody thought it would throughout the ranges with both manifolds. WAY BETTER.

My rig was 35HP better up top and from 4600 on it stretched out quickly. I looked at the sheets... I'll guess that stroker is going to be done with max HP around 5700 or so. Still going to be a solid runner with a good tune staying out of detonation.

Running a street car driving around town, I'd leave the RPM on that stroker, although, the arm would make a big difference in the lower end tq. Again, whatever you're after in the end.
I figure given almost hemi size displacement, that single plane would benefit up top, give it more rpm and make it more linear overall. That’s my view. I may be wrong.

I will work on the owner of this to switch cams and intake after 1st season of driving. That would really wake it up and take advantage of compression better.

He is in full whine mode now because he just paid for body, paint, interior, bumpers, wheels, tires and everything else basically. As usual he underestimated the cost by a lot.
 
About this small cam…
Owner bought this engine as a fully rebuilt unit. We didn’t plan any stroker kit. He wanted some good street cam and it was specked based of compression that this was supposed to have. Engine was sitting for years before I got it to check what’s inside. Unfortunately I found water damage.
Crankshaft was also useless because whoever assembled it damaged it with rod bolts. You can see “new” bearings…
Rings corroded so much that I needed to hammer out brand new pistons.

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That looks awful nice. Is it just the angle of the pictures or does that oil pan sump look really far forward?
Ok I will say it, this is going into 73 Challenger with RMS suspension kit.
You guys are the best so I posted this here for opinions.
 
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