Need advice racing a 380 horse crate engine

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My 292/108 didn't even start making power until 5000.
And it liked 7000,same as all the cams I have run,lol
Well maybe not "liked" exactly, but I wound 'em up anyway lol.
Actually I think that cam power peaked at ~5600 IIRC, but that was 18 years ago. So the shift-rpm coulda been as low as 6300 with an A833. Perhaps 6600 with a 727.
But yeah OP's power seems down; it should be going over 100, perhaps as high as 106
I suggest a compression test, to start with
 
MPH is way low. Before you spend any money, figure out why. As already mentioned, Secondaries not opening is a likely culprit. Especially since you say it doesn't care where you shift at. I prefer dp over vs carbs.

holleyspr1.jpg
 
In comparison I have a 67 Notchback that is not too terribly different than yours all steel body full interior total street car. 360 stock except .510 hyd. cam, air gap intake, 750 dp Holley, Mopar elect. ignition, headers 3" exhaust dumped in front of axle, 3:55 gears , 904 with 11" conv. One trip to track with no tuning and it ran 13.20 @ 105 running 275 60 15 drag radials. so you are leaving something on the table somewhere.
 
In comparison I have a 67 Notchback that is not too terribly different than yours all steel body full interior total street car. 360 stock except .510 hyd. cam, air gap intake, 750 dp Holley, Mopar elect. ignition, headers 3" exhaust dumped in front of axle, 3:55 gears , 904 with 11" conv. One trip to track with no tuning and it ran 13.20 @ 105 running 275 60 15 drag radials. so you are leaving something on the table somewhere.
this is a good comparison- I'm going to check out the secondaries on my carb to start with.
 
are you sure the secondary's are fully opening with that vacuum carb ?
Check the carb linkage too. I have seen on several occasions where the carb linkage is not opening the carb all the way when the gas pedal is on the floor.
 
Yeah you keep saying that, but when the tires spin to waaaay past the speed limit, who cares. It was/is a street car
I care that someone will foolishly follow the stupendously stupid (you) in Erving there engine to the moon in an effort to go fast but in reality will only go slower and probably damage there engine from over reving.

That’s why!

Sometimes you post good and wise advice, the other 80% of the time I wish you would STFU and refrain from posting BS and foolishly bad advice.

Why would you rev over 1,000 past peak power in an effort to fail in going fast on a “Who cares it’s only a street car!” Reasoning!
 
Cuz we're not in the racing forum?
Cuz it's my engine;I can rev it to whatever I want to?
Cuz it wasn't a recommendation,
but merely a statement of fact about my combination,
which as a streeter was built by me and for me to do what ever the heck I wanted it to do..... and it does a darn fine job of it, and has been for over 100,000 miles, since 1999?.
I had no problems at WOT with that 292/292/108 cam, spinning the tires to 60 plus mph, with 3.55s. Thing is; most guys will install that cam at 104 to 100. You just gotta try it at 110, to see what it does, or 112,lol. See I did that. Both.And then it has a power kick that feels like 2-stroke dirt bike; nothing, nothing, nothing then all of a sudden it's WHAM! and almost as suddenly it's time to shift. It wasn't done pulling yet at 7000.

Plus I put an "lol" in there just for you, cuz I knew you would jump in there again and unload both barrels. You do it every time. I guess you just can't help it......
 
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Didn't read every post. Something way off here...
example: I ran 14.11 at about 97 mph with virtually a stock 360, no headers, stock converter, 2.45 gears. With 3.55's, 3k stall, headers, and a 380 crate, i'd think very low 12's.
BEFORE I would buy one thing for the car, I'd figure out what cylinder isn't firing, or why the throttle is only coming open 1/2 way, or...… get the picture? something major here.
 
I would open the exhaust up and see what happens

Another comparison for you

I have a 67 Valiant. 360 with stock bottom and 484 cam(I’m told). The rest I know. Aero 2.02 heads, RPM Eddy, 600cfm Eddy carb, TTI headers and HEI coversion.

Stock converter, manual valve body, 4:56 gears and DOT 26” slicks

1/8 mile 8:80 @ 79 mph through the 2 1/4” headpipes, thrush welded and full 2 1/2 tailpipes.

8:65 with the headers open
 
Cuz we're not in the racing forum?
It should have nothing to do with what forum we are in dummy.
Cuz it's my engine;I can rev it to whatever I want to?
BS reason, child like, you can do better.
Cuz it wasn't a recommendation,
but merely a statement of fact about my combination,
which as a streeter was built by me and for me to do what ever the heck I wanted it to do.
When you state such .... lol... facts..... in the manor you did on top of it all, it becomes a strong suggestion at the least and a weak recommendation at the worst.

I had no problems at WOT with that 292/292/108 cam, spinning the tires to 60 plus mph, with 3.55s.
Sorry to read your suspension is/was sub par.
Perhaps better tires so you don’t (dangerously) spin tires at 60mph is in order.

It wasn't done pulling yet at 7000.
In the spirt of experimentation, I know this as well. I have also found it to be a wasted trip to that rpm range. But you can stress your engine anyway you see fit. Do so enlighten us to the oiling mods you made. You know the ones you left out that all should know about just Incase they try and copy you.
Plus I put an "lol" in there just for you, cuz I knew you would jump in there again and unload both barrels. You do it every time. I guess you just can't help it......
The first half is you trying to save face, a lie, but failing.
(It’s OK, I still like you)
After the coma, and the second & 3rd sentences is you grabbing at straws and at best, 50% true on the most awesome day you’ll ever have.

Is see bull, I call bull. And you can help but to spread it..... bad advice....
 
I got out of racing 8 years ago and sold most of my racing stuff. went to the track a few weeks ago just to watch and got the urge to race again. I figured my 67 barracuda notchback street car would be a good choice to race in the street class and keep things affordable. The car has full interior, all steel except a fiberglass hood. The engine is a mopar performance 380 horse crate engine with a 750 vacuum secondary carb, doug's headers, pertronix 3 ignition set at 35 degrees total advance all in by 3000 rpm. trans is still fully automatic 727 from 727 specialist with an 11 inch 727 specialist converter advertised 2400 -2600 stall. rear is 81/4 with 3:55 and a new sure grip unit. I run 28 inch tall tires on street but I have a set of 26 x 8.5 slicks so I put those on thinking it would help the effective gear ratio. I ran the car this past week and the car hooked well, never missed or popped or hesitated but the best time was only 14.21 in the 1/4. 60 foot times were 2.05. 1/8 mile times were pretty consistent 9.16 to 9.18. it made no difference leaving the car in drive and letting it shift itself at 4500 or shifting it manually at 5700. I know I need a better converter but I want to keep the car drivable on the street and would like to keep the 3:55's. I have been told switching the m1 intake to an edlebrock air gap would help. I know for bracket racing the car just needs to be consistent but it would definitely be more fun if I could get into the low 13's or high 12's. What do you guys suggest? I should mention the car has 21/2 inch exhaust with flowmaster 40's that dump at rear axle.


I've been looking this over and it's my belief that you've got serious tuning issues; I put a Teener into the 13's at 98 mph; it's in the 13 sec combo list; my guess is that your secondaries are not opening up. Find a DP, even if it is smaller than your 3310, a 600, or 650 will cause less of a lay down vrs a 3310 not opening up all the way.

Try moving your shift point up, 5700 seems just a little low on the scale to me, I'd try 6000-6200

Good luck!
 
It should have nothing to do with what forum we are in dummy.
BS reason, child like, you can do better.

When you state such .... lol... facts..... in the manor you did on top of it all, it becomes a strong suggestion at the least and a weak recommendation at the worst.


Sorry to read your suspension is/was sub par.
Perhaps better tires so you don’t (dangerously) spin tires at 60mph is in order.


In the spirt of experimentation, I know this as well. I have also found it to be a wasted trip to that rpm range. But you can stress your engine anyway you see fit. Do so enlighten us to the oiling mods you made. You know the ones you left out that all should know about just Incase they try and copy you.

The first half is you trying to save face, a lie, but failing.
(It’s OK, I still like you)
After the coma, and the second & 3rd sentences is you grabbing at straws and at best, 50% true on the most awesome day you’ll ever have.

Is see bull, I call bull. And you can help but to spread it..... bad advice....
See what I mean? I give you ammo and you shoot; you can't help yourself.
Op is not a first timer
 
I got out of racing 8 years ago and sold most of my racing stuff. went to the track a few weeks ago just to watch and got the urge to race again. I figured my 67 barracuda notchback street car would be a good choice to race in the street class and keep things affordable. The car has full interior, all steel except a fiberglass hood. The engine is a mopar performance 380 horse crate engine with a 750 vacuum secondary carb, doug's headers, pertronix 3 ignition set at 35 degrees total advance all in by 3000 rpm. trans is still fully automatic 727 from 727 specialist with an 11 inch 727 specialist converter advertised 2400 -2600 stall. rear is 81/4 with 3:55 and a new sure grip unit. I run 28 inch tall tires on street but I have a set of 26 x 8.5 slicks so I put those on thinking it would help the effective gear ratio. I ran the car this past week and the car hooked well, never missed or popped or hesitated but the best time was only 14.21 in the 1/4. 60 foot times were 2.05. 1/8 mile times were pretty consistent 9.16 to 9.18. it made no difference leaving the car in drive and letting it shift itself at 4500 or shifting it manually at 5700. I know I need a better converter but I want to keep the car drivable on the street and would like to keep the 3:55's. I have been told switching the m1 intake to an edlebrock air gap would help. I know for bracket racing the car just needs to be consistent but it would definitely be more fun if I could get into the low 13's or high 12's. What do you guys suggest? I should mention the car has 21/2 inch exhaust with flowmaster 40's that dump at rear axle.
 
3580lbs @ the line, stock 340 '71 Cuda,+ .484/284 hyd., stock valvetrain, dual plane, 750DP, small tube hdrs, stock l/springs, 3.55's, 8x26 slicks, B&M Super Holeshot conv., 13.3's @101 all day long with a best of 13.18, thats making just over 300hp on the track, max 6k rpm....even@350 actual hp you should be going 108, forget the ET with that conv....dump the VS for any DP and go again.
 
I'm of the mind that it isn't making power. Does it make compression? Are the secondaries opening?!? You said it didn't make a difference shifting at 4700 or 5800? That should have made a HUGE difference. Like 10 MPH. Running on half a carb would explain it. So would a serious exhaust issue.

Should be able to confirm the secondaries by ear. Take off the air cleaner and floor it in 2nd gear. The "Ba-waah valve" should have opened by 3000 RPM.
 
A paper clip on the secondary vacuum canister rod works for checking secondary opening.
 
Finally got some dry weather so I could drive the car and check the secondaries. The secondaries were definitely not opening. I had a new vacuum diaphragm so I installed it with a yellow spring, secondaries still didn't open. I have a 750 double pumper i'm going to throw on tomorrow and take it for a ride. Should make a huge difference. Ever since I put the crate engine in the car it just spins the street tires at the hit of the pedal so I never really knew the car was down on performance until I put some slicks on it and made a few passes. Hopefully I can make it to the track again before they close for the year and see what the car runs with secondaries working. Then I'll have a converter built over the winter, possibly switch to a dual plane intake and 3.91's. Thanks to everyone for all the advice.
 
Finally got some dry weather so I could drive the car and check the secondaries. The secondaries were definitely not opening. I had a new vacuum diaphragm so I installed it with a yellow spring, secondaries still didn't open. I have a 750 double pumper i'm going to throw on tomorrow and take it for a ride. Should make a huge difference. Ever since I put the crate engine in the car it just spins the street tires at the hit of the pedal so I never really knew the car was down on performance until I put some slicks on it and made a few passes. Hopefully I can make it to the track again before they close for the year and see what the car runs with secondaries working. Then I'll have a converter built over the winter, possibly switch to a dual plane intake and 3.91's. Thanks to everyone for all the advice.


I've said this SOOOOOOO many times that I had to get dentures but I'll mention it again. 99% of the time vacuum secondaries don't open. You can clearly see this on a dyno.

Yes, you can dick around with them until the secondaries come open, but it usually gets at best a small bog, and with no accelerator pump you start changing bleeds a **** to get it on the booster quicker blah blah blah.

Like I've said, they are boat anchors and I throw them away, along with the ever useless 660 center squirted carbs.
 
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