AJ's Opinion; my super-fun, 360/A-833/3.55 street-combo

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>>back to the build. I have decided that YOUR street build for a clutched car should have a C/E of exactly 224* lol. . In at the right spot, you can have very good extraction at 108 allowing a compression of 116*. So then just pump up the pressure short of detonation and yur done.
Now I'll go out on a limb and say that you might find twenty cams to fill this bill, at a C/E of 224*; IDK maybe a hundred. So we need to narrow it down some.
First on the hit list is Powerband. If you run 3.55s like me, you have a two-gear streeter. That is to say that you can hit 60mph at the top of Second gear. So you have just one shift to deal with, and the tires will be spinning all the way thru First, so really, you have no powerband to be concerned with, so you can run any LSA you want to. If you want the big power number, get you some overlap, and run 106 or less LSA. If you want the top of the rpm band to stretch out so you can rev it to the moon try a 115LSA.
Lets see what this looks like.
Because my car spins 325/50-15s to way past 65 mph, I don't care about any dyno power number; she already has way more power than the chassis can handle. So I like to rev it!
Lets start with about 50* of o'lap, and I get 268/278/111.5 in at 110 .
Lets pump it up to 60* of overlap, and I get 272/284/109.. in at 108.
Lets try 70* of overlap and I get ............. 278/288/106.5 in at 105.
All of these theoretical cams have the same 224* C/E. All of them are going to have the very same CCP(Cranking Cylinder Pressure) and all of them will have the same extraction of 108*..
The 278 cam will make the most power, well I should say has the potential to make the highest number on a dyno. Not just because it has the most intake degrees, but partly also because of the large 70* of overlap.
The 268 cam is the smallest and has very little useful overlap so it will make the smallest number...... but it will hang on to it's power longer after the powerpeak...... because the LSA is so much wider.
Which one would I run? Well I have already run 53/61 and 76 degrees of overlap, so Ima liking the big numbers and I don't care if it only carries the power to just 300 after the peak, so Ima thinking 80* of overlap!! That would take a 282/294/104 cam. However, the exhaust duration is starting to wander way off into left field so Ima thinking to abandon the idea of adding any more overlap to the 224CE
So Lets go back and look at the 272/284/109. The exhaust was already wandering back here, lets see if we can clean it up. Lets reduce the exhaust to 4* split and increase extraction from 108 to 110 for a new C/E of 226 a very nice number. And the cam becomes 272/276/110 in at 108, and the Compression remains at 116. Overlap drops to 54*
This would make a GREAT street cam, with just enough of each event to make it work, with the exception of overlap that is just 54* .. But hang on, with 3.55s and 27s, 60mph is just 5100 in 1.92 Second gear so um........ do we need more overlap? Answer; no we don't, lol.
So then think about this; If you limit your combo to 3.55s and run a Mopar A833, that sets your rpm to 60=5100 in Second gear; why do you want to build a 430hp monster, that will never get to it's powerpeak, and more than likely will have a softer bottom end... hmmmmmmmm
IDK but automatic-guys do it all the time.
By my trapspeed of 93 in the Eighth at 3457 pounds, the Wallace Calculator says that takes 430 hp. ...... so apparently so did I (build a monster). But not on purpose, I can assure you. All I ever wanted was to not have a wussy bottom end, and make decent mpgs so I could make her my DD.
Ok so where are we on the build?
Well first off, I only cut my decks to get away from the .028 gaskets, which couldn't, I thought, take the 190psi. It turns out that lots of guys here on FABO are running, or have successfully run, those .028s with a proper deck prep. So My failure was not the norm. But I didn't know that.
So then, slam your fresh-bored and honed 360 together with the KB 107s at whatever, down-in-the-hole, and use the .028s ; just remember to rough up both the decks and the heads to give them something to hang on to.
I run the alloy heads so I can pump up the pressure, and forget about the actual numbers, so long as it is over 170psi. I took my engine apart every winter 6 in a row, looking for evidence of detonation on 87E10 and never found any, even at 190psi. So I mean how could I lose? She runs cheap gas all the time, runs massive pressure, gets great fuel economy and went 106 in the Qtr at 3650 pounds with the smallest cam. 106 could be a mid twelves car, so that was fast enough for me.
It turns out that the Eddies with my small cams have no problem running to 7000 rpm or more, mine have been there hundreds and hundreds of times. Did I build it for that? No! They just happen to hang on really well.
After that, just bolt on whatever. I started with the factory iron intake and a TQ. then an Excellerator and several other carbs all VS or AVS or TQs. After a while I figured out my combo was lousy with an un-controlled by my foot, secondary, So when the AirGap came out, I got me one right away and bolted a 750DP on top. As a streeter it ran great with every one of those...... but I think the AG is part of why the small cams I run, keep on pulling long after peak.
As for cams I liked the 270/276/110 the best. The 227* C/E is just right. In at split overlap it gets great fuel-economy even down to say 1800 rpm.
But the truth is; If there is a next cam, it will be Solid-Lifter cam with a similar .050 to what my Hughes HE3037AL cam has, but with less advertised. It will have a tighter LSA than 110, less stagger than 276/286, and more overlap than 61*, lol. I really want my fuel mileage back without a loss of midrange and without a higher rear gear. It turns out that 2240rpm@65mph is a fabulous cruiser gear, and living in the country, I do a lot of cruising..

So that's my story