Anyone Here Ever Dyno Their Mild Built Small Block Car?

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DartThis74

DartThis74

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I had the opportunity to run my '74 Dart Sport on a Mustang Dyno yesterday. I'm from Katy, Texas and a performance shop called Bumberas Performance upgraded my carburetor from a plain worn out holley 750 vacuum secondary to a Holley 650 HP Ultra. It woke the engine up to an insane degree and made it feel like it came out of hibernation or something. :D To my surprise when I picked up the car the paper read that at the wheels the car pulled only 215 HP :wack: Although that was only at around 4500-5000 rpm and could of gone a little higher, but still... just from driving the car it feels way more than that.

Has anyone had their mild built small block car on a dyno before and were your numbers around 215 or so ? Did any of you get your hopes up on your build thinking the numbers would be higher than anticipated? Full setup specs detailed below on my '74 Dart sport build.


- 1985 Dodge maxivan 360 engine
- mopar m1 dual plane intake
- lunati voodoo cam - Advertised Duration 256/262, Lift .454/.475
- Holley 650 HP Ultra
- Engine bore .030 over
- cheap summit racing brand headers
- 727 trans with 2k stall converter
- 8 3/4 rear with 3.23 gears.
 
From what I've read there is about a 60 HP loss at the rear wheels. So you could be at 275 HP or more at the motor. An even bigger problem is that every dyno is different, and every dyno operator operates it different. You could have this done at several places and get wildly different results.
 
Seems about right and it should feel pretty snappy at that horsepower. We had a 318 that had the same horsepower to the rear wheels with 3.91 gears in a 71 Scamp. It ran 14.90s and 95-96mph in the quarter mile.
 
DartThis74 said:
I had the opportunity to run my '74 Dart Sport on a Mustang Dyno yesterday. I'm from Katy, Texas and a performance shop called Bumberas Performance upgraded my carburetor from a plain worn out holley 750 vacuum secondary to a Holley 650 HP Ultra. It woke the engine up to an insane degree and made it feel like it came out of hibernation or something. :D To my surprise when I picked up the car the paper read that at the wheels the car pulled only 215 HP :wack: Although that was only at around 4500-5000 rpm and could of gone a little higher, but still... just from driving the car it feels way more than that.

Has anyone had their mild built small block car on a dyno before and were your numbers around 215 or so ? Did any of you get your hopes up on your build thinking the numbers would be higher than anticipated? Full setup specs detailed below on my '74 Dart sport build.


- 1985 Dodge maxivan 360 engine
- mopar m1 dual plane intake
- lunati voodoo cam - Advertised Duration 256/262, Lift .454/.475
- Holley 650 HP Ultra
- Engine bore .030 over
- cheap summit racing brand headers
- 727 trans with 2k stall converter
- 8 3/4 rear with 3.23 gears.
Click to expand...

What heads are you using?
 
IQ52 said:
Seems about right and it should feel pretty snappy at that horsepower. We had a 318 that had the same horsepower to the rear wheels with 3.91 gears in a 71 Scamp. It ran 14.90s and 95-96mph in the quarter mile.
Click to expand...

It is very snappy actually. I have a stage 2 shift kit in the trans. and it kicks in pretty good when shifting and kickdown is nice. I do get a little chirp in the tires when 2nd gear hits.
 
DartThis74 said:
I had the opportunity to run my '74 Dart Sport on a Mustang Dyno yesterday. I'm from Katy, Texas and a performance shop called Bumberas Performance upgraded my carburetor from a plain worn out holley 750 vacuum secondary to a Holley 650 HP Ultra. It woke the engine up to an insane degree and made it feel like it came out of hibernation or something. :D To my surprise when I picked up the car the paper read that at the wheels the car pulled only 215 HP :wack: Although that was only at around 4500-5000 rpm and could of gone a little higher, but still... just from driving the car it feels way more than that.

Has anyone had their mild built small block car on a dyno before and were your numbers around 215 or so ? Did any of you get your hopes up on your build thinking the numbers would be higher than anticipated? Full setup specs detailed below on my '74 Dart sport build.


- 1985 Dodge maxivan 360 engine
- mopar m1 dual plane intake
- lunati voodoo cam - Advertised Duration 256/262, Lift .454/.475
- Holley 650 HP Ultra
- Engine bore .030 over
- cheap summit racing brand headers
- 727 trans with 2k stall converter
- 8 3/4 rear with 3.23 gears.
Click to expand...

Heads and compression ratio? Did they monitor the A/F ratio and actually tune the carb and adjust timing?

Also, were you satisfied with Bumberas? I moved out to Katy a few years ago and have been wondering about the performance shops around here.
 
you've been reading too many build posts that dyno'd a big number (dyno'd by the builder)
a stock early 340 was about 275 - 280 hp and those that lived through the era know how
well these engines pulled in an A body.
your numbers look good and your car should work great.
 
ir3333 said:
you've been reading too many build posts that dyno'd a big number (dyno'd by the builder)
a stock early 340 was about 275 - 280 hp and those that lived through the era know how
well these engines pulled in an A body.
your numbers look good and your car should work great.
Click to expand...
X2^^ These 400 HP Ricers are a joke. Most are no where near that. your numbers sound ok for what you have.
 
74DartSwinger said:
Heads and compression ratio? Did they monitor the A/F ratio and actually tune the carb and adjust timing?

Also, were you satisfied with Bumberas? I moved out to Katy a few years ago and have been wondering about the performance shops around here.
Click to expand...

heads/compression I am unsure of... I didn't have them go through the whole fine tuning aspect honestly. I originally brought the car in to look at my holley 750 because it was stumbling and there was a vacuum leak somewhere. Ultimately they said the carb I had on there was garbage, which I had no doubt it was, because it was very old and worn out. Kenny Bumbera is a carburetor guru and had some new HP Ultras laying around and gave me a great price. He worked very well with my budget, they talked to me about everything they were going to do or were wanting to do and waited for my approval. Just go over there and talk to them and they will probably show you around the shop too. It's basically a classic car performance shop. I will be taking my car there for now on because of how well they treated me and my car and providing good knowledge and info.

His policy with the carbs is, if you don't like it for whatever reason he will buy it back from you or put the carb as payment toward something else. If you decided to rebuild your engine with higher performance parts with a carb you purchased from him he will use the money you spent with him and credit it toward a carb more suitable for the rebuilt engine. He also provides a couple years of warranty too.
 
DartThis74 said:
It is very snappy actually. I have a stage 2 shift kit in the trans. and it kicks in pretty good when shifting and kickdown is nice. I do get a little chirp in the tires when 2nd gear hits.
Click to expand...

Then ignore the numbers game and be happy with it. It's about the same flywheel HP as the 340s were and we all know their reputation.
 
The only part that the dyno would have helped with is the change with the carbs. So you pull twice to establish a baseline, then replace the carb, then pull to tune, then pull two more times to establish the change. Comparing numbers between dynos is not accurate. So the next step for you is to get to a track, get an ET/MPH, then weigh the car as it was raced. Use the MPH as the power indicator because that's reality as basic as you can get.
 
If your happy, your happy. I work with a guy that was happy with his "292" '55 Ford, until he learned it was a "272". I asked him upon that knowledge if his car got slower? He said "no", I said be just as happy.....

Along the lines, don't let a number or somebody else's opinion dictate your happiness. I know guys that are thrilled with a 15 second ride, and some run 12's and feel it's slow. You decide for you.....
 
Is a higher stall converter in your plans? 2k is pretty tame, a 3000 and a trans cooler will make it rev a bit faster and quicker off the line
 
318willrun said:
If your happy, your happy. I work with a guy that was happy with his "292" '55 Ford, until he learned it was a "272". I asked him upon that knowledge if his car got slower? He said "no", I said be just as happy.....

Along the lines, don't let a number or somebody else's opinion dictate your happiness. I know guys that are thrilled with a 15 second ride, and some run 12's and feel it's slow. You decide for you.....
Click to expand...

Right on ! I am happy with how the car drives, its response, and torque. I should take it to a track, it would be pretty interesting to see what it can do. I'm not dissatisfied with the number. Just from driving the car around and playing with it, knowing it runs like a scalded cat and then the performance shop saying it pulled 215, I thought for sure it would of been more. I was curious to see what everyone else that put their mild built small block car on a dyno got out of theirs. This is the first time I've ever had a car on a dyno and it is interesting.
 
I usually go by "seat of the pants" you know when a car is fast, and its all relative what's fast to me may be slow to you. Racing is always about who chickens out first, on the street anyway LOL! :)
 
I wouldn't get to hung up on dyno numbers, they are nothing more that a tool. Just like tire pressure gauges, one will read different than another.

Like others have mentioned if you're happy does it really matter what it made?
 
Excellent for just a carb change.:finga:Carb spacer will aid.Fresh air in and get it out.650 ultra is a double pumper.750 has vacuum secondaries.you need first gear in autos for the butter flies to open at WOT.(at idle).Me I like gearing down from 3rd or 2cnd to first,with VS carbs.A little better on gas just crusin around.
 
the lil red express EH1 engine put out 225 horse, but had a hell of a "seat of the pants feel" .....its the 340 ft/pds of torque that you felt.... =@#% the numbers as long as your happy with the performance
 
Most powerful production motor for its time...late 70s.we were running out of oil too....lol
 
Toss it on the dyno of a couple members here. It'll gain 50hp at least.

If you're happy with it, I say just tune what you've got and drive the sumbitch.
 
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