Thread: 302 Stroker??

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Originally Posted by 34_40

Randy, I'll somehow figure out how to get a video for you....

Mike, I'm so glad you're trying to abide by the rules!!!! Video will be great!!! Pics will suffice in the meantime.....

Originally Posted by randyr

Mike, I'm so glad you're trying to abide by the rules!!!! Video will be great!!! Pics will suffice in the meantime.....

YOU! Want pics from ME???... I'll tell you what, show me/us any progress on yours and I'll do the same! Besides, only 2 others besides me ever look in here!

Now tell it to my little friend!!

Mike,
I somehow missed that you got the engine running with the cross flow fours! I really like the look, and the air cleaner sitting at an angle is going to draw attention to that manifold. The only thing that would make it look better is to have it sitting in something in my shop instead of yours. I agree with Randy, we need a video of the gas gauge to see if it's reverse acting with the tach & speedometer

Thanks Roger! As I said to R2, I'll need to learn how to shoot and post videos.. we'll take you for a ride!

The dual four's won't be as bad as you think, unless you drive with your leg in it all the time. This setup was for road racing and endurance racing where mileage is always a consideration, with the linkage and jetting correct they do just fine!!!!!

And I think the vacuum secondaries will help in that department.. fella I've been chatting with on the side, runs this same setup, dual 390 holleys with the vacuum secondary, he won't quote a mpg number but says it isn't any worse than the single 750 he was running on a stroked small block.

But I really don't care about mpg honestly! The car only has 1 purpose after feeding my creative side. And that's to help me relive my younger years by scaring the snot out of me when I put the small pedal on the right to the floorboard! It hasn't failed me yet!

Luckily, the police chief is a family friend in town... but, I cannot strain that relationship much further! They call it "Exhibition of Speed" when you smoke the rear tires.. but the fine is relatively soft..

My brother and S.I.L. were over from Texas a couple months back and during the ride with my brother, I stomped into the throttle and the car jumped sideways!

When we got home my parents asked him about the ride and how he liked it.?.?

All he kept saying was "Never Again"!!

I do remember a number of cars running this setup successfully in SCCA racing, we played with them on a Shelby for half a season, then went big block and A Production instead the next year.... I do remember playing with jetting, linkage, and secondary springs along with a long stroke on the gas pedal to make the power transition more even and less likely to blow the tires off the car coming out of a turn, or just going up through the gears..... Could really adjust that "transition rate" (as our driver called it) on acceleration. As mentioned, the next season was a 428 CJ....no such thing as sneaking up on the power with that monster in the car!!!!!!!!! First race of the season at College Station with the big block, Ben spun the car 3 times....all 3 on turn exit!!!!

them longer gas pedals have been one of the best race invintions ever!!!!!!!!!!!!!!

I saw an advertisment from Shelby American which had all his manifolds spread out around a young lady in a cowboy hat. In the description for this manifold, "they" claim it to be satisfactory for street operation. By the way it behaves right now, I have to agree. The car actually runs smoother right now, even the sound is smoother / calmer than with the dual plane!

Now I just have to wait for the snow / ice and the salted roads to go away.

I believe a lot of that comes from the more equalized flow characteristics of the manifold....

BYW===When the roads get fit for playing again, I'd suggest a good vacuum gauge installed when you start playing with the secondary springs.... Holley makes a really neat quick change kit for the secondary springs. Getting the secondary springs set to work progressively and at or near the rate of the progressive linkage will make the setup smoother, improve driveablity, and improve efficiency!

PS--You're really making my feeble old memory work here Mike!!! We also played with the advance rate on the mechanical advance side of the distributor----got any friends with an old Sunnen Distributor machine in their shop??????

One vacuum gauge is installed permanently in the dash, and I wish I knew who had a distributor machine.
Right now I've got the advance stretched out to 40' at 2200 rpm... but I was reading one of RSpears posts and he mentioned that he was cautioned that the pistons wouldn't tolerate that.. I think I may back off just a bit, get the advance back to 35 / 36.

The little engines can take 40----just not for long!!! I've ran 38 and 40 on lightweight drag cars, but there's a lot of difference between a few passes on race gas with a 5 speed and a driver, backing it off to 36 is good....

Best thing about the old distributor machines, could play with the rate at which the advance came in rather then just what the total was. Could do the same thing with a really quality timing light with a dial and digital scale on it (I've got a Snap-on light that will do it) and checking the advance every couple hundred RPM and see when and how much advance is coming in..Very tedious, maintenance intensive, and probably not necessary at all on a street engine.....

With the new Coyote engine it's "easily(?)" done just by mapping the advance curve and the fuel curve to match, then another couple grand worth of data acquisition pieces to verify it when it goes down the track!!!!! Everything is easier if you can just sit back and throw money at it, huh?

Yeah, tossing money can make some of it easy.. I have the snap on dial back light and use a external vacuum gauge and tach and it takes a long time to gather data, make an adjustment, retest, repeat....

You know what I'll be doing this weekend!

Pistons are dumb----------------


The issues of timing------------people talk about degrees of timing before top dead cender---it actually comes down to Time ( you know, one of them absolutely constant values, like gravity????) If spark could be set by time in milli seconds, you could run many more degrees of timing ----


Reason we are limited on the street to more restricted numbers with the lower quality fuel is it burns much faster (ever noticed how often you got to stop for gas?) and with the timing numbers we run for midrange(to me that's low range--) there is more time for the fuel to burn and reach that pressure point at say 2000 rpm than at 8000 rpm----------The reason we can/need to run more advance for wot operations is to enable the flame front to reach that sweet spot for the flame/pressure front, piston/rod/crank angles, etc which ironilly is past top center on the way down------------

Originally Posted by 34_40

One vacuum gauge is installed permanently in the dash, and I wish I knew who had a distributor machine.
Right now I've got the advance stretched out to 40' at 2200 rpm... but I was reading one of RSpears posts and he mentioned that he was cautioned that the pistons wouldn't tolerate that.. I think I may back off just a bit, get the advance back to 35 / 36.

Like Dave says, it's easy when you're playing with a Spark Map, just boxes on a chart! My limit came from the fact that I have KB Hypereutectic pistons, and KB puts a 36 degree limit on timing for those pistons. Other pistons don't carry that limit, and even with that limit mine pushes up to 40 degrees at and above 3000rpm when MAP is 10"HG or less. Basically, this is an economy setting because the only way the engine can ever see that part of the curve is throttle closed coasting down a hill with high rpm. That feature came from the guy at Edelbrock, and he said that they often crank up to 44 to 46 degrees in that zone because it's almost never seen and there's virtually no load on the pistons at that part of the map. I chose to limit mine to 36 degrees under load (MAP 12 and above), ramping up to a peak of 40 on the lines for Zero and 10"HG above 2500rpm. If you're in that zone and blip the throttle, total timing drops immediately to a peak of 36 - boxes on a chart, telling the ECU what to do.