Rat Rod Engine Dyno Testing - Zoomies! - video Dailymotion

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00:00 (upbeat music)

00:02 It's Fry Burger from Hot Rod

00:08 and we've got the Mighty Marshmallow here.

00:10 It's a cheap ratty little small block

00:11 and we're gonna be testing some cool stuff

00:13 like a tunnel ram and zoomies.

00:16 (engine revving)

00:18 The victim today is a real cheap 350 Chevy

00:26 that I threw together.

00:27 The bottom end is a bone stock 91 truck motor

00:30 from a junkyard.

00:31 Up top we've got some SR Torque World Products

00:34 170 iron cylinder heads.

00:36 It makes 9.1 to one compression.

00:39 I threw in a Comp Cam's hydraulic flat tap at cam

00:42 which is a thumper.

00:43 It's 224, 241 at 50.

00:46 It's designed to make really cool noise.

00:48 (engine revving)

00:49 Check this out.

00:50 The valve covers themselves are brand new reproduction

00:54 MT cast finned covers from Holley.

00:57 They just reintroduced them which is really cool.

01:00 I sort of helped talk them into doing that

01:02 so go buy a set so I don't look too stupid.

01:05 Topped off with a Nettle Brock Performer RPM intake

01:08 right now in a 750 Holley.

01:10 I don't expect a whole lot out of it in this configuration.

01:13 Let's find out what it does.

01:15 (engine revving)

01:18 (engine revving)

01:20 We just made the first pull and that little mouse

01:29 was actually better than I expected by a little bit.

01:32 Made 351 horsepower and 393 pound feet of torque

01:37 which is pretty decent.

01:38 The intake that we have on it is what I would consider

01:40 to be the best all around street manifold

01:43 for under 6,000 RPM on that Nettle Brock RPM air gap.

01:48 And so now we're gonna put on the tunnel ram

01:50 and see if it's better or worse.

01:52 (rock music)

01:54 The thing that's unusual about these carburetors

02:03 is they're 450 CFM four barrels which makes them tiny.

02:07 But also you'll notice they're not vacuum secondaries.

02:10 They're mechanical but they're not double pumpers

02:13 because they don't have a secondary squirter.

02:16 Only in the primary.

02:17 They also only have a jet block in the front

02:20 and just a plate in the back

02:21 so their tunability is pretty limited.

02:24 This whole combo here is actually a package

02:27 you can get from Summit Racing

02:28 that comes with the Y end, gaskets,

02:31 both carburetors and the linkage for 850 bucks.

02:34 - That's what it's about.

02:36 - Yeah, what price is there to look this cool?

02:39 (engine revving)

02:41 (engine revving)

02:44 - Nothing!

02:57 - Ah, that's okay.

02:58 - It runs the same.

03:00 - A little bit there but it's fat.

03:01 - Yeah, it is fat.

03:03 What we're doing right now is the engine

03:06 was just a tiny bit fat.

03:07 It was 11.9 to one at peak power

03:10 and let's be honest, we're way too lazy

03:13 to actually rejet two carburetors

03:15 and so we're leaning it out

03:16 just by reducing the float bowl level.

03:19 The gas is in here and actually the weight

03:21 of the column of fuel acts on the jet,

03:24 almost pushing the gas through the jet

03:26 and if you lower the float bowl level,

03:28 it reduces the weight of that column of fuel

03:30 and actually leans it out a little bit.

03:33 Trust us, we've done it before.

03:34 Watch this.

03:35 There you go.

03:39 Take care of the fuel curve

03:40 and it actually comes up another 10 horsepower

03:42 or something.

03:43 That's pretty good.

03:45 What we're looking at here is the difference

03:46 between the first pull that we made

03:48 with the tunnel ram which peaks at like 11.9 to one,

03:51 something like that.

03:52 It's a curve of air fuel ratio

03:56 and so this is fatter because it's a lower number

03:58 and this is leaner because it's a higher number

04:01 and we accomplished that just by lowering

04:03 all four float bowls.

04:05 We didn't jet it at all.

04:09 Red lines are performer RPM air gap.

04:12 Black lines are the tunnel ram.

04:14 So we've made just that much more horsepower

04:17 up here with the tunnel ram

04:18 and then they're matched all through here

04:20 and then it's kind of anybody's game down here.

04:23 It made 12 horse, yeah, 351.8 to 363.5

04:28 and it peaks at the same RPM with both intakes.

04:32 A big part of the reason we did this thing

04:34 is sights and sounds.

04:35 It looks cool and it has to sound cool

04:37 which is why it has that comp thumper cam in it.

04:40 Now the thumper has more overlap than you would expect

04:43 and also more exhaust duration so that it sounds cool.

04:47 So I'm gonna idle it down

04:48 so you can hear what it sounds like.

04:50 (engine revving)

04:55 Here's another thing is that a lot of guys

04:59 were saying on our Facebook page

05:00 that this is gonna have no throttle response

05:03 and you can't drive it on the street.

05:04 Well, first of all, I think it's idling at about 800 RPM,

05:07 but watch this.

05:08 You can drive that car.

05:14 Next, Cherry Bomb three inch header mufflers.

05:24 Hello, Steve, get back to work.

05:28 (laughing)

05:37 This is the moment I've been waiting for all day

05:39 because I've never run Zumis before.

05:42 These are Sanderson headers and they're pretty cool.

05:45 Sanderson makes a lot of neat stuff

05:47 and also these, they look cool.

05:50 That's a dumb motor.

05:52 - That should just be on a T-shirt.

05:54 - That's right, we can do that.

05:56 We're waiting for Mike to shock himself.

06:05 (laughing)

06:07 Yeah!

06:15 Fire, dude.

06:18 That is what awesome looks like, that right there.

06:22 (engine revving)

06:30 (engine revving)

06:33 Yeah, that killed power.

06:40 Don't care.

06:41 On average, it's bad.

06:43 The area under the curve's bad,

06:45 but you know what, like I said before,

06:46 this is sights and sounds.

06:47 This is not truly about making horsepower.

06:50 You put that thing in a 2,100 pound rod of any kind,

06:54 and trust me, you can scare yourself 20.

06:57 What'd you learn today, Mike Finnegan?

07:00 - Today I learned that although they look awesome,

07:04 Zumis don't really work on weak suck small blocks.

07:08 I learned that you can get electrocuted

07:12 via your wedding ring.

07:14 - And that was funny.

07:16 - And,

07:18 that rod engines are cool.

07:23 - Yeah, I learned that this is, I think,

07:25 the first dyno test I've ever done

07:26 that wasn't just about making more power.

07:28 It was about entertainment value.

07:30 And it still made 360 horsepower and 390 foot pounds of torque

07:35 all below 5,500 RPM.

07:37 So it's not a complete pooch,

07:39 but it looks cool.

07:42 We're out.

07:43 (upbeat music)

07:45 [BLANK_AUDIO]

Rat Rod Engine Dyno Testing - Zoomies!

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