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Flat top pistons, Mondello cam, port work on factory heads as well as a basic valve job. Factory intake, quadrajet and headers... made 398 HP vs factory max gross rating 310 HP.
The vids alone didn't give me that laundry list. Besides watching all 3 thoroughly you need to go through the comments of each one. Nick himself filled in some of the blanks in the Q and A sections.
I have an foggy memory that says someone once upon a time bought edelbrock total power package, and got out maybe 315hp. Was disappointed.
Id say the total power package would be to send your engine to any of the builders presented here, tell your hopes, and pay the bill.
Wow only 400 with aluminum heads ?. Waste of money. The bucks garage build was pretty much BS. Too. Sorry but those 2 examples leave alot to be desired. By comparison my iron headed 355 based off weight and E/T makes 425 . My last combo made 380 with a hydraulic flat tapped and unported iron heads.
Last edited by coppercutlass; November 29th, 2020 at 01:39 PM.
Wow only 400 with aluminum heads ?. Waste of money. The bucks garage build was pretty much BS. Too. Sorry but those 2 examples leave alot to be desired. By comparison my iron headed 355 based off weight and E/T makes 425 . My last combo made 380 with a hydraulic flat tapped and imported iron heads.
I’m not sure it had aluminum heads. Did you see somewhere that it did?
The Edelbrock catalog lists a 350 with iron heads, RPM Cam and intake, 9.5:1 and an Edelbrock 750 carb as making 397hp. I talked to a couple of Edelbrock people a few years ago about this build. They mentioned “it had some bowl work and a little gasket matching done”,
Based on your numbers as well as a couple of iron headed builds I’ve done, those numbers make sense.
It would be cool however to compare an iron headed combo vs the same combo with the same size chamber aluminum heads, back to back. Maybe that’s something I’ll put on the list for my mule.😎
It looked like aluminum in the video. I went back a few times but I could be wrong. Quality is not the best lol.
You know what I thought about and I will personally be doing this is. I'm building a clone of my engine. Except it will have the speed pro flat tops ( it's what I got lol ). But the plan is to build a back up motor same cam same compression same intake but use un ported big block iron heads with a 2 inch valve and just bowl work with the risers filled. I'm building my car to run a 12.0 index so best E/T won't be the case if that big block headed sbo either falls short or runs better the car will have to be held back to run the number. But I honestly think the power will be very close imo and that's big think but I got enough crap to make it happen. But that would be a good test for you too.
Last edited by coppercutlass; November 29th, 2020 at 02:08 PM.
Great comparison for Procomp or Edelbrock heads on a fairly mild 350. People claim with lower compression with a milder cam, aluminium heads won't gain much over iron up top and loose low end velocity on a 350. I would also take those "useless" small chamber aluminum heads off your hands as well😁.
Location: Colorado Springs Colorado/Thousand Oaks Ca
Posts: 1,719
Originally Posted by coppercutlass
Wow only 400 with aluminum heads ?. Waste of money. The bucks garage build was pretty much BS. Too. Sorry but those 2 examples leave alot to be desired. By comparison my iron headed 355 based off weight and E/T makes 425 . My last combo made 380 with a hydraulic flat tapped and unported iron heads.
Hp is calculated by MPH over 1320 feet, 112 MPH @ 3500 pounds? in negative DA is 378 crankshaft HP. Et has nothing to do with it. On the dyno surely your a little over 400 HP.
Using Wallace ET says my production ovalport/block BBC's make 890 HP we know thats a pipe dream.
Last edited by VORTECPRO; November 29th, 2020 at 06:33 PM.
According the weight and e/t that's my number. there is a calculator for crank HP it does not make sense to me how they can calculate crank hp from mph considering the power loss through drivetrain can vary from set up to set up. When you calculate what the et should be by HP and weight. It backs that up. When you calculate the HP figures you gave me the only way the numbers add up is if you factor 15 percent power loss through drivetrain. That's to say since your Hp is based off of mph its going through the wheels I don't think they can calculate the loss percentage enough to truly give you crank Hp so imo that has to be through the wheels.
Edit.
I did some math and HP from et was 380 to the wheels 425 to the crank. Add the 2 decide by 2 and you get 402 as an average
Hp from mph was 328 to the wheels and 363 crank add the two divide by 2 and you get 345 Hp as an average
Now add the 2 averages divide by 2 and you get 373 that's the average between HP between E/T and MPH. Which supports your number vortec. .
Not to hijack the thread but clearly behind these figures lies the efficiency of the car and drive train which I honestly dont know if that can be accounted for or not. But if you plug 373 hp into an crank HP to 1/4 mile calculator for my weight the only thing that matches is the mph. E/T comes to 12.76
When you punch in 425 Hp crank for my weight e/T is 11.67
The averages between these 2 don't even match so how do factor efficiency
Last edited by coppercutlass; November 29th, 2020 at 07:35 PM.
Location: Colorado Springs Colorado/Thousand Oaks Ca
Posts: 1,719
All my race cars in 500 feet DA or under will show dyno HP which matchs up with the Moroso power speed calculator and or the Wallace racing site MPH HP calculator.
Example 1: A 370 dyno HP NHRA stocker will run 11.70s @ 3500 pounds, because its utilizes all the available power, the difference is in the drive line and power carry.
Example 2: My 10.8 compression production oval port headed, production block 496s have run 9.29 in 615 DA air, how is possible this 496 makes 890 HP, it doesn't, but dyno HP was 780 HP, Wallace MPH calculator says 790.
Example 3: My NHRA stock 315HP 455 Buick makes 516 dyno HP first time around, ran 10.70 @ 122.3 @ 3650 pounds, Wallace ET calculator says 588 HP, Wallace MPH calculator says close to 516 HP.
I could show many examples of this. Some cars utilize power more efficiently, this why on the dyno your over 400 HP but show 370s running down the track. My NA 327 shop truck @ around 4000 pounds will run 112 MPH in good conditions, but will barely break into the 11s due to the fact its very inefficient, heavy brakes, two piece drive shaft. This 327 made 445 dyno HP. A truck is down at least 2 MPH to car due to wind resistance. Put your 350 Olds in my Buick, you got a under 11.50 car, because now its a race car. Make no mistake you've put together a great street/strip car, the best I've seen on here for what it is and the money spent.
I'am partial to my shop truck though LOL
Last edited by VORTECPRO; November 30th, 2020 at 07:59 PM.
Again not to hijack the thread but it's a subject I have been very interested in because the calculated numbers always vary between different ways of calculating HP. Thanks for the insight.
I have an foggy memory that says someone once upon a time bought edelbrock total power package, and got out maybe 315hp. Was disappointed.
You have a great memory ! I remember coming across that also. Your post further motivated me to really dig into it. Its fellow member 71 Cutlass and boy was he disappointed, he mentions it in many different threads...
For those not that familiar I will give you a cliff notes version.
71Cutlass and 2 of his buddies all decided to give the Edelbrock 397 HP Power Package a shot back in the early 2000s. All 3 had low compression post 1970 350s. In other words all 3 engines with the factory top of the line setup have a peak max gross factory horsepower rating of 260 with headers. At the flywheel.
When these weekend gearheads were all said and done they took there rides to a dyno shop and saw an average of 220 HP to the wheels.
Id say the total power package would be to send your engine to any of the builders presented here, tell your hopes, and pay the bill.
Depending on your expectations yes.
If you want to see that 400 HP or better with as little headaches as possible you want to send the engine and package to VortecPro or CutlassEfi or the like. But and this is a big one, that's not to say that a carguy/gearhead will not see good gains there own way. CopperCutlass would of worked wonders with this power package IMHO.
In reality 71 Cutlass and his buddies did very well. HotRod magazines 1968 F85 saw 215 HP to the wheels with headers from a 310 HP high compression 350. So as you say Inline they saw about 315 HP flywheel rather than 397 but that's still a 55 HP pick up over the best of there stock engines and they did it without headers.
They say they were disappointed in the way the cars felt on the street but did they ideally upgrade other components of the powertrain to fully take advantage of the engine mods... He mentions better gearing and torque converters but did they smooth out all the wrinkles via test and tune... HotRod magazines F85 would destroy any factory small block made after 1970. 14.27 @ 96.15 MPH is muscle era 442 performance. HotRod's 215 wheel HP had a killer go package. Set up is key.
I could likely add 50 more HP to my 69 but without modifying the drivetrain to take advantage of the additional power and I think I would see little to no performance gain. Set up is everything. My current factory powertrain set up is leaving up to 30 HP on the table give or take as is. Modifying the drivetrain to take advantage of my current power may do very little to take advantage of another 50 HP.
Maybe a 3.23 will give me a nice bump in performance as is. But maybe I need a 3.55 to see gains after an engine mod...
I stand by the YouTube vids I posted about, it gives you a decent idea of what's possible.
To further add to my previous post. That 71 Cutlass did very well producing 220 wheel hp, if he looked at it a certain way...
I present you this.
HotRod magazine dropped in a W31 350 in that same F85 and saw 225 HP to the wheels with headers. It ran 14.08 @ 98.90 MPH with factory tires. That's factory muscle era W30 performance.
For future enthusiasts thinking about adding HP to there engine.
The 3 key HP ratings methods should always be kept in perspective.
Flywheel gross
Flywheel net
Wheel horsepower
Mixing them up can make for plenty of confusion and possible disappointment.
Superchevy ran some tests that showed the wide range of readings.
Flywheel Gross, open headers 383 stroker = 425.8 hp and 473.8 lb-ft of torque.
Wheel horsepower, in a 1972 4 Speed M22 Vette = 283 hp and 341 lb-ft of torque.
In the end the 383 lost 1/3 (33.5%)of its gross power to the wheels. Make the Vette a automatic all else the same and it will lose even more horsepower...
They also tested a 1970 450 HP Automatic LS6 Chevelle and saw 283.5 HP to the wheels. That's a 37% loss.
Flywheel net to wheel is a whole new animal. Fellow classicoldsmobile.com member jpoole tested his completely stock 1983 Hurst Olds at 75,000 miles. Factory ratings are 180 HP and 245 LB FT torque. Wheel dyno showed 150 HP and 194 LB FT. That's only a 17% loss.
( I am assuming completely stock means factory exhaust, otherwise true dual exhaust puts you at 200 HP fly, then 150 HP wheel is a 25% loss)
Either way massive percentage difference in loss between gross and net when goin to wheel.
November 29th, 2020, 03:32 AM
