One of my cars is a 67 Barracuda notchback. I had a fresh 360 in it .020 over all stock except a performer RPM intake and 600 Holley 1850 carb. I came across a 360 / 380 horse power Mopar Performance crate engine that was brand new and decided to buy it and throw it in the car. I had read a lot of articles that stated these ran pretty good with a 750 Carb and headers. I thought it would be a considerable improvement over the engine I had in the car and could still run on pump gas. I swapped the engines and originally tried running it with the 600 carb from the old engine and 340 exhaust manifolds, and an original type distributor with a pertronix ignitor module installed. The car ran horrible. I borrowed a 750 Holley 3310 from one of my other cars along with a Mopar performance electronic distributor with an orange box. The engine ran a little better but idle was erratic and I could hear detonanation when the car shifted or when I gave it throttle. I tried initial timng at 10 before and kept backing it off but still had detonation and the engine wanted to run on after shutting it down. I checked engine vacuum and after seeing it had 5 inches of vac. at idle I switched to a 2.5 power valve which cured the idle problem but I still had detonation, run on and low performance. I had read where the advance curves for the Mopar Performance distributors was really quick and when I would try to use the vacuum advance on the distributor the detonation was worse. I bought a pertronix ignitor 3 mechanical advance distributor which comes with 3 sets of different tension springs and 3 different sets of advance limiters. I set the distributor up for 20 degrees of advance all in @ 3500 rpm. I set initial timing @ 10 degrees BTDC for a total of 30 degrees. I didn't want to try any more advance due to the detonation problems I was having. I took the car for a ride and there was no detonation but it still runs like a pig. I still have the 340 manifolds on the engine because I don't want to go through all the hassles associated with small block headers. Even the super expensive headers are a pain. I can't believe the manifolds are robbing that much power. The trans is a 727 with a B&M holeshot converter, the rearend is 81/4 with 321 gears. I know the converter and gears aren't the best to be running with this engine due to the single plane intake and cam profile but if this engine is even close to 380 HP in the best coditions I feel it should oerform better than it is. It sounds great at idle, it doesn't miss, pop, fart or anything. I'm running what is supposed to be 93 octane premium. Are these engines that over rated? Am I missing something obvious? I've been doing this a lot of years and have run everything from a 9 second 500 CI Duster to my 64 Fury with a bone stock Poly engine. I think my poly actually has more power than this crate engine. Anyone have any experience with these engines?
360 CI/ 380 HP Really?
- Thread starter 500duster
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abodyjoe
Well-Known Member
i run my small blocks at about 17 initial and about 35 total. never have a problem with 93 octane gas. sure you aren't overlooking something?
I have read in a few mopar mags this engine is low 12 sec in a duster easily . but I heard some complaints about the quality of machine and assembly work also
That cam would be incorrect. The 360/380hp create is a Magnum engine. It has a roller cam @ 288 intake duration. I have seen these engine perform at the track (E-town in summer) in the mid 12's in a full dress Duster. Strip/gutted race only Dusters close to mid 11's which is real nice considering the hot humid weather that day.
The create 360/360 had the Hyd. Purple 292/.509 cam.
Follow what AbodyJoe is telling you and look twice over everything. Check the damper vs actual TDC, distributor, coil etc...
And sorry to say, but those exhaust manifolds are killing power. MP recommended a header @ 1-3/4 IIRC W/ a 750 carb. These have dyno'd north of 400HP.
The rear tire is what size?
The create 360/360 had the Hyd. Purple 292/.509 cam.
Follow what AbodyJoe is telling you and look twice over everything. Check the damper vs actual TDC, distributor, coil etc...
And sorry to say, but those exhaust manifolds are killing power. MP recommended a header @ 1-3/4 IIRC W/ a 750 carb. These have dyno'd north of 400HP.
The rear tire is what size?
That's right 360/360 was the first non magnum motor .
Still with that cam an 3:23 gears and his torque converter along with the exhaust you mentioned it is mismatched . A stock matched combo would more then likely run better .
Still with that cam an 3:23 gears and his torque converter along with the exhaust you mentioned it is mismatched . A stock matched combo would more then likely run better .
cudavert
DARTAHOLIC
I'm a bit surprised you mentioned you put a 600 CFM carb and that "headers are a pain" for an engine that's obviously built to scream. As for the detonation, all I can think of is (what was mentioned about timing/harmonic balancer) or that your jetting isn't quite right or it's running too hot.
Give it what it wants, man!......as in, set it up how it should be set up.
Give it what it wants, man!......as in, set it up how it should be set up.
autoxcuda
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Made that much 380 HP because of the cam. Now you have to live with that cam.
I know a MP guy that sold an absolute ton of those SB crate motors. He'd try to explain the consequences and street manners of the 380HP vs the 320HP motors. But most were stubborn and bought the 380HP. Then a year later they would call asking for ways to "get it to idle better" and "get it to run smoother" or "get to run as good, but with less gear". They wanted to detune it, but were too proud to flat out admit it.
I know a MP guy that sold an absolute ton of those SB crate motors. He'd try to explain the consequences and street manners of the 380HP vs the 320HP motors. But most were stubborn and bought the 380HP. Then a year later they would call asking for ways to "get it to idle better" and "get it to run smoother" or "get to run as good, but with less gear". They wanted to detune it, but were too proud to flat out admit it.
I guess the combination of gears, converter, manifold with the cam and single plain intake could all add up and kill the performance. I was looking for the best of both worlds -- a pump gas cruising car that would still run decent.
I sold my pro street Cuda last year which was a true 10 second street car (10:52 @ 128 1/4) because I had not driven it in a few years because of price of race gas , noise , climbing around bars to get in and out etc. I guess I'm getting older and my priorities are changing.
I took the 4:30 geared 3rd member out of my challenger this summer and put a 3:55 3rd member in to make it more streetable. I was surprised it really did not effect the performance that much but it did make it a lot more drivable. I guess I was thinking if the gear change didn't hurt the performance of the Challenger I could get by with the mild gears and the crate engine in the 67 notchback. However the Challenger is a big block with more converter, higher comression so I guess it would be more forgiving as far as gearing.
I'll double check everything with this crate engine. If I decide to keep it in the car maybe I'll try a set of headers. Would you guys suggest TTI, Dougs, or the Schumacher Tri y headers? I don't want a high stall, gear bound street car. I've had enough of those over the years. Which were a ton of fun when I was younger and all the drag strips were still open and they made real gas. What is the recommended converter and gearing for the 380 horse crate engines?
I sold my pro street Cuda last year which was a true 10 second street car (10:52 @ 128 1/4) because I had not driven it in a few years because of price of race gas , noise , climbing around bars to get in and out etc. I guess I'm getting older and my priorities are changing.
I took the 4:30 geared 3rd member out of my challenger this summer and put a 3:55 3rd member in to make it more streetable. I was surprised it really did not effect the performance that much but it did make it a lot more drivable. I guess I was thinking if the gear change didn't hurt the performance of the Challenger I could get by with the mild gears and the crate engine in the 67 notchback. However the Challenger is a big block with more converter, higher comression so I guess it would be more forgiving as far as gearing.
I'll double check everything with this crate engine. If I decide to keep it in the car maybe I'll try a set of headers. Would you guys suggest TTI, Dougs, or the Schumacher Tri y headers? I don't want a high stall, gear bound street car. I've had enough of those over the years. Which were a ton of fun when I was younger and all the drag strips were still open and they made real gas. What is the recommended converter and gearing for the 380 horse crate engines?
67Dart273
Well-Known Member
What bothers me is the detonation?
Regardless of poor converter/ gears
poor exhaust
and "I guess?" the engine is not overheating?
Damn thing should not detonate
Has someone had their fingers into the engine?
Is it possible you made a REALLY stupid mistake, like, maybe, the heat riser butterfly is stuck partway shut?
Regardless of poor converter/ gears
poor exhaust
and "I guess?" the engine is not overheating?
Damn thing should not detonate
Has someone had their fingers into the engine?
Is it possible you made a REALLY stupid mistake, like, maybe, the heat riser butterfly is stuck partway shut?
No one had been into the engine from what I could tell. Not over heating and heat riser not stcuk shut. The new pertonix distributor seemed to cure the detonation. I just removed the advance limiters from inside the distributor so I will have 34 degrees total timing. I'm going to take it for a ride after bit and check for detonation and see if the 4 degrees of timing helps at all.
Those 360/380 are a stock magnum long block with a big cam and single plane intake, with the mag's relatively low CR and a big cam shouldn't be detonating, if you don't want to go gears, converter and headers a intake and cam swap might be in your future, the 300hp create is a stock long block and cam with a dual plane intake, a milder cam and dual plane will put in between the 2 engines hp wise.
If they still made these crate engines and I had a choice I would have definitely gone with the 300 HP version. If I'm right Mopar discontinued these engines several years ago and now only offer a 400 HP version which has aluminum heads and the price is north of 10 grand. I got what I think was a pretty dood deal on this crate engine from a guy that has a large collection and bought the engine for a project and then went a different direction. I have 2 or 3 10 " converters on the shelf I could throw one of those in. I have a brand new posi unit for the 8 1/4 that is in the car now but I have always preferred 8 3/4 so I guess I could sell that posi unit and put the money towards finishing an 8 3/4 with steeper gears. I have some carriers and gears but need an A body housing and axles. I had a guy tell me that the 68 - 70 B body housings were only an inch wider. I'll have to Google some measuremnts. If that is true I could just move the perches as I have enough clearance to go 1 inch wider. That would just leave headers. As mentioned earlier I just hate wrestling with headers. They never fit right, the underhood temps warp fiberglass hoods over time, plug wires burn and on and on. I ran Hooker fenderwell exits on my drag car and they were great as far as easy removal, getting to plugs, starter etc. The fenderwells were already cut when I bought that car. I don't want to cut holes in this car.
txstang84
Well-Known Member
B body 8 3/4" will fit after you relocate the perches...I think they only have to go in like 1/2" on either side.
I dig that you're not a fan of headers in an A body, but to get best performance out of that engine in its current config, you're better off dealing with dropping a good amount on good headers once and going from there...and wrapping them to help stave off the other issues you mentioned.
I dig that you're not a fan of headers in an A body, but to get best performance out of that engine in its current config, you're better off dealing with dropping a good amount on good headers once and going from there...and wrapping them to help stave off the other issues you mentioned.
powerwagonpaul
Well-Known Member
I think you should have more than 5 inches of vacuum at idle, make sure you don't have a vacuum leak
You could pull the cam, have it reground. That is a big cam.230/[email protected],ground on a 108 lobe center.Anv duration ,288/292 I.I.R.C. Or throw a converter at it. I like the rump,tuning does take time. What can you live with?
pauly v.100
Well-Known Member
I put a brand new 360/380 in my car after blowing up the 340 it had, the crate Magnum runs much better than what you're describing.
A68DART360
Well-Known Member
I personally had the same motor in my 68 Dart GT and it was a full bodied car except no heater and that motor is a 12.60-12.80 engine. My car with my 250 lbs added to it was right at 3500lbs. I had a 750 carb, TTI headers and about a 2800-3000 stall.
moparmanestock
Well-Known Member
The Non-Magnum 380HP 360 does have the 508/292 hyd flat tappet cam. It is available in shortblock form. That is what I am running. And the engine does make over 380HP.
moparmanestock
Well-Known Member
The 508/292 cam is too big duration wise for your combo. The duration at .050 is 246 or so. You need a 750 carb, headers, converter and lower gears, at least 3.91s. This cam was intended for bracket racing, not street use. You should look for a cam with a duration of 230 at .050 or so. Mine idles at 900 with 4.5 inches of manifold vacuum, not very friendly for power brakes.
That engine is built for a loose converter and at least a 3.91 gear and free flowing headers and a 750 carb. Even with the added 750, you still have lousy gearing and a stock converter.
That said, I agree with Del. It should not spark knock. Initial timing will have a very negligible effect on spark knock, as long as the curve is set correctly. Which Mopar distributor was in there? If it was the Mallory unit, the Pertronix was a down grade. I would guess that it was not the Mallory unit. Those older MP distributors did not have an adjustable mechanical advance and were notorious for really hot curves.
All that said, still it is the manifolds, converter and gear that's killing your engine. That's three big things against it. The 380 HP engine is essentially a mild race engine and that's the type things it needs to run well.
That said, I agree with Del. It should not spark knock. Initial timing will have a very negligible effect on spark knock, as long as the curve is set correctly. Which Mopar distributor was in there? If it was the Mallory unit, the Pertronix was a down grade. I would guess that it was not the Mallory unit. Those older MP distributors did not have an adjustable mechanical advance and were notorious for really hot curves.
All that said, still it is the manifolds, converter and gear that's killing your engine. That's three big things against it. The 380 HP engine is essentially a mild race engine and that's the type things it needs to run well.
HotLines
Realist - Free Thinker
There's nothing like a magazine article to make one squirm in their pants...
What gears and converter are you running?
The mopar performance ignition I tried was borrowed out of my 73 340 Barracuda. I bought it around 1991 if I remember right. I currently have the new distributor set at 10 degree initial and 34 total all in @ 3500. I hear no detonation now. Changing converter is no big deal since I have 2 or 3 10 " converters from other projects over the years. I almost threw one in when I was swapping engines- kind of kicking myself in the butt over that one. Would a set of Doug's headers do the trick? If I was racing it I would shell out the extra $ for TTI .this is just a street car that will get driven a few times a year-just want it to run decent
AdamR
Big Member
10* initial isnt enough for the motor. I would shoot for 15 to 18*
The Dougs headers will be fine.
What converter and flex plate do you have now ? The magnum motors use a different balance then earlier 360 LA motors.
The Dougs headers will be fine.
What converter and flex plate do you have now ? The magnum motors use a different balance then earlier 360 LA motors.
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