Well, I found the limit of stock CR & lil cam

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wigsplitter74

The Mopar Kid
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Went drag racing this weekend and I'm pretty sure I found the limits of my 360's stock bottom end and small "340HP" cam. Somehow I got it tuned great and it would swallow a 750DP from a dead stop to WOT. The absolute best I could get out of this car was a 14.01 lol I thought maybe I'd see a 13.80 or 90 but it wasn't gona happen. Maybe instead of going bigger this winter I should leave it alone and bracket race it as this things gone 14.0x about 8 times now lol I also found that no matter how I launch it 60fts were 2.00. No, the car didn't go as fast as I had hoped for but hey I had fun and ya can't expect too much out of a mostly stock motor right. It's gettin cold now and the motor's comin out and apart, enjoy the off season fellas.
 
Sounds like fun anyways. Tell me the details of this.

Year/actual ratio of engine, cam size, tranny and gears etc.........
 
Depending on the rest of the combo, sometimes doing a studder step leave will get you faster. That's when you dont go full throttle but rather stop just before the secondaries begin to move, and then when the car's rolling a foot or two go the rest of the way down.
 
I've been able to get 13.7's on my mostly stock 360 and a 600cfm carb. The last time I went it ran 14.1's and 14.2's consecutively. Come to find out I had mostly clogged fuel filter which is still a mystery since its a new tank.
 
Went drag racing this weekend and I'm pretty sure I found the limits of my 360's stock bottom end and small "340HP" cam. Somehow I got it tuned great and it would swallow a 750DP from a dead stop to WOT. The absolute best I could get out of this car was a 14.01 lol I thought maybe I'd see a 13.80 or 90 but it wasn't gona happen. Maybe instead of going bigger this winter I should leave it alone and bracket race it as this things gone 14.0x about 8 times now lol I also found that no matter how I launch it 60fts were 2.00. No, the car didn't go as fast as I had hoped for but hey I had fun and ya can't expect too much out of a mostly stock motor right. It's gettin cold now and the motor's comin out and apart, enjoy the off season fellas.

Glad to see you had fun, ran consistant, & most importantly, didn't break 8)

Sounds like a perfect candidate for a little juice i'd say, that'll wake it up nicely :-D, thats what my plans are with my next build, keep it mild & throw the bottle at it!! FunFunFun.
 
I think you could've gone faster with a little more tuning.

I had a 318 that was running high 13s with nothing more than cam, 750 carb, headers and 360 heads.
 
What was the MPH on the runs? That would be a better indication as to what's left in it.

ET is in the suspension, tire, converter.

With a 2.00 60', I bet there's a .10-.15 improvement available there alone, which would be about .20-.30 on the other end in total.
 
What rpm were you shifting it? If too low, the motor could be falling below the "sweet spot" after the shift. I guess it kinda doesn't matter, since you're tearing it down. Stay warm in that garage!
 
yrs ago...when i had first purchased my duster 340 auto....
i took it racing...it went 14's i put headers and protrac tires.
torquer intake ..it went 13.50's dead on...i wont 4 races the first yr.
and lots of money...(for a 17 yr old)
mid way into the second season...(after winning another 2 events )i decided to put some of the money in the motor.so i could go faster..
My buddy and his father (friends and co. racers) begged me not to touch the car.....it was a money maker...
tore it down ..put pistons,cam,head work.intake carb rockers...
the car went 12.40s....
and ithink i won maybe 1 race with that motor...came to a couple of semi's
but it was never as consistant ....
traction became the factor..and temp changes..moved the et...alot.
just some stuf to chew on..fwiw
hve a blast.
cheapst.
 
it's a 74 Duster, 73 360, never actually checked the CR but it's a stock style piston +.030, the X heads have probably been shaved a lil in the past IDK for sure. It's a 727 with a 10" 3000 conv. and turbo action RMVB, It's got 3.91 gears in an 83/4 with a 255/60/15 MT ET radial. It didn't matter if I loaded up the converter or left soft then went WOT, 60's were 2.0 either way. the cam is the MP 430/450 lift cam, it's got an MSD ignition system w/ mech. advance, headers and 3" exhaust, I shifted it at 6,000 and the mph was 95-96 (it's been 98 in the past) With a little more tuning I suppose it could have run better, but I tuned it to the best of my ability and as I'm just 20 and have only had it done for 2 of the 4 years I've owned it I'm happy. The night before I was talking with a friend who has a nitrous kit for his EFI trans am and I almost borrowed a plate and his kit to spray 100-125 at it but since it was the first time I had it tuned well enough to go full throttle from a dead stop with a 750DP I wanted to see what it'd do, and I didn't wana be up til 3 or 4am putting on the kit and trying to tune it for spray lol. I'm sure there's a little bit left in it with a more experienced tuner but oh well, it's getting redone this winter. I also think my balancer has slipped cuz it seemed weird while setting timing and it broke up bad on the first pass at what shoulda been good timing according to the balancer. Oh it also has a stock replacement fuel pump and stock tiny fuel lines and pickup, changing that though.
 
6000 rpm is spinning too high for that camshaft.

Try shifting at 5000-5300 and see what it does. It probably tops out around there. The range on that cam from mopar was 1200-5200 IIRC.

Likely a case where less will be more regarding RPM.
 
You also could use a bigger cam. And pocket port the heads.
 
cam makes power to 5200 but pulls til around 5800 so maybe stretching it a bit but oh well I did try shifting before the light on one pass and it went 14.1 instead of 14.0 lol Oh well it's time for something different, I'd build a 451 but I'd rather not put a roll bar in my car, it makes people cry race car 8)
 
I'd build a 451 but I'd rather not put a roll bar in my car, it makes people cry race car 8)

Funny you said this, i ran 10.8/10.9s with my 451 & never got around to installing the roll bar i bought for it lol, when i sold the car, the new owner installed it, car ran faster (mph anyways) & he was 150 heavier then my scrawny azz, don't sweat haveing a roll bar, i should have installed mine, even without it, once they saw the car run, any talkers would shut up & wouldn't line up with me roll bar or not, if you "really" want a 451, then build it!!
 
So you ran 8 runs within a tenth in a weekend? Not too shabby. If it were me, I'd focus on reaction times and go have some fun with it for a season. I've seen a whole lot of 15 second cars make the final round all summer long and rack up serious points.
 
Funny you said this, i ran 10.8/10.9s with my 451 & never got around to installing the roll bar i bought for it lol, when i sold the car, the new owner installed it, car ran faster (mph anyways) & he was 150 heavier then my scrawny azz, don't sweat haveing a roll bar, i should have installed mine, even without it, once they saw the car run, any talkers would shut up & wouldn't line up with me roll bar or not, if you "really" want a 451, then build it!!

Beleive me, in the next 5 years or so I will build a 451, I've got the 400, know of some forged 440 cranks and have talked to a machinist I know about the work, I even bought a swap meet 187 pan for $10 lol, but I'd need to build a trans and in everything I'd need for the 451 I could build my 360 twice lol I guess I'm just not done playing the SB game yet. and at our local street race style events it's hard to get a race with a big block, everyone assumes it runs 8's or something crazy and wants 20 cars and the hit :angry7:

So you ran 8 runs within a tenth in a weekend? Not too shabby. If it were me, I'd focus on reaction times and go have some fun with it for a season. I've seen a whole lot of 15 second cars make the final round all summer long and rack up serious points.

Well actually only 7 runs were within a tenth, the first run it broke up so that was 2 tenths off LOL yea I'd probably do alright bracket racing, 90% of my reaction times are .03x-.08x so I'm doing my job driving I guess. I guess I'm just ready to go faster and have been putting money aside to do so, always gotta have more. Might still put that 125 shot to it and go play one last time this year but I doubt it.
 
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