Yeah, 4500 is just a guess at this point, basically it would work with my solid ft cam but going solid roller now
Anyone running a 470 in a dedicated drag car?
- Thread starter MOPARMAGA
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What's your opinion with -14 cc dome pistons will get my static to 14.1:1, as it sits I may be able to squeeze 11.8:1 that's with the piston .008 out of the bore & .022 of gasket above that for a total of .030 gasket thickness. Is the flame travel impeded enough to hurt performance ? I'm confident in my abilities to massage a piston, get the cc's matched & weighed the same. By the way the heads are 78 cc trickflow 240s, I'm using 6.70 rods & 1.320 ch +6cc now.
yellow rose
Overnight Sensation
What gas are you going to run? I'd pick the gas that you're going to run first and then pick the compression ratio to match the gas. If C12 is available in your area then that is a good gas to design around. For a race engine where you're willing to buy race gas like C12 then 13 or 13.5 should be a good safe compression ratio that will allow you to run in any weather. If you already own the pistons then 11.8 would be fine. I made more than 700 hp with less compression than that but that was a fairly trick engine.
Yes i have they're +6 cc's
octane level I haven't figured yet. I haven't seen any c12 around my area
You answered my question. Yes you're right your engine had less compression, should be just fine. You had some stuff I probably won't, that oiling system, the crank trigger, & belt drive system, pro ported intakes, & probably some things i forgotten.
yellow rose
Overnight Sensation
It’s here. You have to go downtown. I forget the name of the place but I can drive to it!!!
If you know you have 6 cc’s now and you go to 14...Id have to take your word for it or do the math but if I was doing a race engine I’d opt for the compression.
IMO, 11.25:1 is a pump gas CR if you do it right and I’m up to 11.77 so we will see if I kill it on the dyno or in the car.
I don't have a dog in the hunt, as I have zero experience with the 470 so take this for what it's worth. Nuthin.
I've done a PILE of reading on big block strokers, since I was considering one at one time. It seems to me that two displacements stick out from all the rest. The 451 and the 470. The 451, obviously because it can use a lot of factory parts and off the shelf pistons, which can make it affordable. That was a big plus to me, as, unlike a lot of yall, I don't have money fallin outta my asshole.
The 470 though seems to be just as good or even better a combo. Since I knew I couldn't afford that one, I didn't do the reading I did on the 451, but if I remember, doesn't it use a Chevy size big end on the connecting rod? That makes for readily available rods = affordable. Buy beyond being affordable, the 470 just seems like there's something magical about it. Kinda like the 340. They make power almost effortlessly. With the 4.150 stroke and the 4.375 bore, you still have an "under square" engine.......which "most" agree is the better way to go. I'm no engineer, so WTF do I know other than what I've read?
I've done a PILE of reading on big block strokers, since I was considering one at one time. It seems to me that two displacements stick out from all the rest. The 451 and the 470. The 451, obviously because it can use a lot of factory parts and off the shelf pistons, which can make it affordable. That was a big plus to me, as, unlike a lot of yall, I don't have money fallin outta my asshole.
The 470 though seems to be just as good or even better a combo. Since I knew I couldn't afford that one, I didn't do the reading I did on the 451, but if I remember, doesn't it use a Chevy size big end on the connecting rod? That makes for readily available rods = affordable. Buy beyond being affordable, the 470 just seems like there's something magical about it. Kinda like the 340. They make power almost effortlessly. With the 4.150 stroke and the 4.375 bore, you still have an "under square" engine.......which "most" agree is the better way to go. I'm no engineer, so WTF do I know other than what I've read?
I appreciate what you wrote. From what i've read, heard & seen a few cars the 470 may be magical, lol. Seems that guys make just as much power with any of em depending on cam carb intake heads & compression.
okay thanks, my builder is trying to talk me away from domes, then the only way to get that compression is go up in cubes. Hmmm what to do
The 470 is a good combination for a bunch of reasons. The parts all fit in the block with plenty of clearance, the pistons are tall enough to be stable, the rod to stroke ratio is decent, the bore size is big enough to promote breathing, the engine size works well with the head size, the parts are all easy to find, etc.
Had the Mopar engineers been more aggressive back in the early 70's they could've built a low deck 470. A factory 470 Duster would've been a monster, even with cast iron heads and manifolds.
Had the Mopar engineers been more aggressive back in the early 70's they could've built a low deck 470. A factory 470 Duster would've been a monster, even with cast iron heads and manifolds.
How much power do you want to make? I thought you just wanted to run 10.0? If so then you already have the rotating assembly that you need.
yellow rose
Overnight Sensation
Exactly how tall is the dome?? I’ll take a small dome and a shorter stroke every day of the week and twice on Sunday.
Plug location is MUCH more critical than a dome. Example? The Hemi. A dome the size of a igloo and still runs on 32 to 35 total. On a SBC or BBM it would take 42-45 total.
Same with a SBM. The plug location is about as good as it gets with a wedge. I have a .187 dome because I need the CR.
They're angled plugs, the dome is -14 Ross pistons, I don't own them or have any to look at, I think Andy may be right he has less compression than I will already & made plenty of power. I do only want to make a 10.00 car (for now) until I can figure out the rest & afford to run faster. I don't know any of those details yet, next season ill be at the track more often asking people.
Or asking you. But honestly I don't even know the questions to ask.
I have a 470 in a 74 duster. 3300 with driver. Foot brake car. 11.2 compression. Yes it’s measured and verified. JE pistons with with a small dome. Stage 6 heads with some porting. Ohio crank, Eagle rods. BRC girdle. 727 with light weight parts. Cam is a Comp solid roller. .625 lift. 275/275 @.050. 108. TM7 intake. 1000 cfm Pro Systems Holley 4150. Converter flashes to 41-42 hundred. Under chassis 2 inch headers. Msd 7AL ignition system. d60 with 4.10s. Super Stock springs with Competition Engineering Slide a Links. Viking double adjustable shocks. Stock front end. 29x11.5 Hoosier QTP slicks. 1.451 60 ft Best run so far is 10.37 @ 129.65 mph. Runs 10.40s all day long. It turns 7000 NA. With Nos it turns 8000 because it revs so quick. It’d runs 9.03 then. Kim
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yellow rose
Overnight Sensation
yellow rose
Overnight Sensation
I like buying once. You can always slow it down if you want.
It’s not always easy to just swap in new pistons.
As a disclaimer, I always run as much compression as I get get for the fuel I use. Always. Up to about 14:1, with the correct fuel there is no downside to CR.
The tune up window gets tighter but they run cleaner and make more low and midrange torque, which is a big deal, especially when you have more than one gear change.
I just wanted you to know that, because I always advocate for CR. So I am very biased about it.
Okay, I think the question is settled then, I have what I need. Thanks
The motor was built in 1998 so idk what exactly was done as I didn’t own it then. I bought it in 2016. The guy that built it doesn’t remember the details anymore. It runs great on 91 mixed with 110 half and half. Kim
I guess that's been my issue, my build started out as street strip, could I get a custom ground cam that would help? Bump up the dynamic compression
If I don’t sell it over the winter the heads will come off to be Max Wedge ported and freshened. I have a Edelbrock Super Victor and a 1250 Holley Dominator for it. And if I really have ambition I’ll change the converter. Kim
yellow rose
Overnight Sensation
TT5.9mag
Two atmospheres are better than one
You could build a very mild 9:1 flat top 451 with a mild cam, street gears, keep the converter you have, and turbocharge it. Drive it to the track on pump swill with the ac on, pour in some race gas and turn the boost up and make all the power, run the number and then drive it home. 7-800 hp is pretty easy to do on boost with a BBM.
Just sayin......
Just sayin......
It's the big Chrysler engine is what it is. That's what's magical. Hell, if you tried hard enough, You could make 700HP from a stock stroke 361. LMAO They're just good at makin power.
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