Moparts
273 FAST cars?
Posted By: HotRodDave
273 FAST cars? - 01/25/09 03:59 AM
I was pondering buying a 65 dart GT and thinking through what could be done with it and thought a FAST car would be unique, obviously not the fastest ever but a 4 inch stroke crank could put it up to around 340 inches depending on final bore, could even go close to 360 with a 4.25 stroke and honda rod journals. Heads could be made to flow enough for 400 hp. It would be a pretty light car with a short-ish wheel base so mabey it could be made to be respectable.
What do you guys think?
Posted By: B1Fish540
Re: 273 FAST cars? - 01/25/09 04:05 AM
hmm..
I like your idea. The heads would have to be really good and still "appear" stock.
Posted By: slantzilla
Re: 273 FAST cars? - 01/25/09 04:09 AM
What's the tire rules? 65 Darts had tiny tires on them, like a 5" wide 14".
Posted By: BBR
Re: 273 FAST cars? - 01/25/09 04:17 AM
3 words:
Sucky exhaust manifolds.
Posted By: scatpacktom
Re: 273 FAST cars? - 01/25/09 05:00 AM
2 words...Do it
Posted By: MoparJoe
Re: 273 FAST cars? - 01/25/09 02:01 PM
Quote:
3 words:
Sucky exhaust manifolds.
I've seen an early A pick up 1/2 sec and 5mph in the 1/8 by just swapping to a set of small headers. This was on a street 360 with stock heads, hyd cam and dual plane, nothing crazy where it would "need" a set of headers, that 90* bend and crimp in the manifold on the dr side kills it.
Posted By: CJK440
Re: 273 FAST cars? - 01/25/09 03:04 PM
Quote:
What's the tire rules? 65 Darts had tiny tires on them, like a 5" wide 14".
Why stroke the 273?? You know that by the rules you are allowed to use any block of that family?? So start with a 340/360 block and put 400+ cubes in it.
You can upgrade to a 6" wide wheel and upgrade to a G series tire of the same section as stock.
I think my car should have 14x5.5's with E7014's. I'm running 14x6 rallyes and G70's.
As for the exhaust, sure headers are going to be better but its a moot point. I am not sure there is a huge difference between "good" small block manifolds and "blah" small block manifolds in the grand scheme of things.
I agree with Tom, do it.
Posted By: HPMike
Re: 273 FAST cars? - 01/25/09 03:04 PM
Quote:
2 words...Do it
Listen to Tom, and just build it.
In FAST all entries have their shortcomings. It's all about doing the BEST you can with the entry you choose to bring. Not too long ago they said a FAST six pack big block wedge would never be able to make it into the elevens.
MB
Posted By: HotRodDave
Re: 273 FAST cars? - 01/25/09 04:47 PM
I thought I read in the rules one time you could not use a block that would take a bigger bore than stock?
Also would it be limited to a single exhaust?
I had a 360 in a 66 dart 4dr with 302 heads 273 manifolds and it ran a best of 9.43 in the 1/8th with a one leg 7.25 2.94 rear.
Could I run an 8.75 or 8.25, I think they only came with 7.25s in 65?
Posted By: CJK440
Re: 273 FAST cars? - 01/25/09 06:02 PM
No, that overbore thing meant larger than the largest factory overbore of that engine family. A factory 340 or 360 is fine for a 273 car.
As for exhaust, thats a good question. The class is for high performance cars with a minimum of a 4 bbl carb and dual exhaust... Thats a question for the FAST tech guys.
You can run any axle offered by that manufacturer. Same goes for transmissions as long as its no more than 3 speeds for auto or 4 speed for stick.
Posted By: Anonymous
Re: 273 FAST cars? - 01/25/09 07:56 PM
Quote:
Could I run an 8.75 or 8.25, I think they only came with 7.25s in 65?
A few late 65's had 8 3/4 rears. Not sure if that was only in 4-speed cars.
Posted By: HotRodDave
Re: 273 FAST cars? - 01/25/09 08:23 PM
The one I am looking at has a 4spd and 7.25 rear.
Mabey the 7.25 could be made to survive with enough weight removal from the car and the puny tires. Any one make a spool or aftermarket axels? The weight saveings of the 7.25 could be an advantage it self.
Posted By: slantzilla
Re: 273 FAST cars? - 01/25/09 09:02 PM
Quote:
The one I am looking at has a 4spd and 7.25 rear.
Mabey the 7.25 could be made to survive with enough weight removal from the car and the puny tires. Any one make a spool or aftermarket axels? The weight saveings of the 7.25 could be an advantage it self.
Don't know of any spools for the 7.25, but Sure Grip units pop up on the Slant board every so often. There was an SG unit and 4.10 gears on there a few weeks ago.
With small street tires a 7.25 w/SG would hold up for a while. 
Posted By: HotRodDave
Re: 273 FAST cars? - 01/25/09 09:32 PM
I made about 50 1/8th passes on my old 66 dart with a 7.25 and finaly broke the spiders drifting through an intersection WOT
Mabey I could get someone with a lathe to turn out a locker?
What about axels? Shot peen, cryo treat and hope for the best?
Posted By: Hemi_Joel
Re: 273 FAST cars? - 01/25/09 09:32 PM
Guys, this discussion is great, but if you are seriously thinking about competing, read the rules, then read them again.
You can use ANY solid axle that ever came in a mopar, or a stock appearing aftermarket version.
http://www.fastraces.org/I hope you build it, I think it would be a cool combo, and you would have alot of fun with it!
Posted By: goldmember
Re: 273 FAST cars? - 01/25/09 09:35 PM
Why not put an 8.8 in it if you want easy. Tell the tech guys it's an 8 1/4 and they would
I wouldn't waste time or cash on the 7 1/4,but thats just my
Posted By: rbstroker
Re: 273 FAST cars? - 01/25/09 10:06 PM
Dave, if I remember the rules for F.A.S.T. you will have to run manifolds and a tire size that was available from the factory. The manifolds are the killer. Why not try NHRA stock class? I believe that you'll find that you can run headers and any size tire that will fit the wheel well. With a 2bbl 273 and a 904, you may fit right into U/SA.
Posted By: DaveDudek
Re: 273 FAST cars? - 01/25/09 10:16 PM
Build it F.A.S.T.!
Posted By: CJK440
Re: 273 FAST cars? - 01/25/09 10:24 PM
Quote:
Guys, this discussion is great, but if you are seriously thinking about competing, read the rules, then read them again.
You can use ANY solid axle that ever came in a mopar, or a stock appearing aftermarket version.
http://www.fastraces.org/
Joel got the point across better than I did. Any mopar axle. And the FAST rules are pretty concise easy to understand. I'd suggest going thru them a few times as I think you'll find most answers there. The forums are a great place for more input too.
Posted By: JohnRR
Re: 273 FAST cars? - 01/25/09 11:16 PM
Quote:
I thought I read in the rules one time you could not use a block that would take a bigger bore than stock?
depends on the combo . 
the killers for performance on a big cube motor in that combo are, the small carb, very small heads, small intake manifold, and poor exhaust.
while you can use any year or size OE block......the heads, intake manifold, and exhaust manifolds MUST be the correct pieces for the original combination.
the carb doesnt have to be the correct part number, but it does have to at least start out as something that was the same size as original.......and in this case, that means "small".
trans and rear axles arent going to be the problem.
making power with be the problem.
Posted By: HotRodDave
Re: 273 FAST cars? - 01/26/09 04:31 AM
I just went back over there to look at the car and noticed how small the carb is and had to come back and read the rules. It is very small and I am sure it would be a big handy cap but NASCAR amateur hour (whatever it is called)makes some serious HP with a smaller carb. The rules state there will be a visual inspection with the air cleaner off, if I have the throat/venturi area ported bigger would that DQ me? Milling air horns is clearly out lawed so
Can I install bigger throttle blades?
Another big problem would be the 13 inch bycycle tires, if I was stuck with them (13s)there would be no point bothering to build the car. Were 14s optional on that car?
Any one know how much a car like that weighs? I think they (early A-bodys)are light, that would be there big saveing grace, if they are heavier than they look that too could be a deal breaker.
I am not thinking I can beat a certain black Hemi car but I don't want to show up and run a 14 second quarter either.
if thats what you want to build.....just build it.
how quick you could make something like that run is pure speculation until you build one and show up at the track with it.
my personal opinion is that its about as poor of a FAST combo as you could find........but opinions are just like....well....you know.
Posted By: dannysbee
Re: 273 FAST cars? - 01/26/09 05:05 AM
Build a 71-72 340 Duster or Demon. The bodys are reasonable the intake, exhaust manifolds and carburator will make plenty of power, over 400 inches is no problem. I believe a purpose built FAST Duster could weigh 3000 lbs without a driver. If I had a brain I would be working on one instead of a Max Wedge car. 400 flywheel hp should put you at around 118 mph. Et would depend on how well the chassis is set up and that seldom mentioned speed part, the driver. I personally believe this would be the best bang for the buck Mopar you could build.
Posted By: Anonymous
Re: 273 FAST cars? - 01/26/09 05:09 AM
Quote:
Another big problem would be the 13 inch bicycle tires, if I was stuck with them (13s)there would be no point bothering to build the car. Were 14s optional on that car?
Yes, 14's were optional in 65.
Posted By: Hemi_Joel
Re: 273 FAST cars? - 01/26/09 01:24 PM
You could run G70-14's on 14x6 rims. You can bore out the carb as much as it will take.
Posted By: CJK440
Re: 273 FAST cars? - 01/26/09 02:20 PM
Quote:
I believe a purpose built FAST Duster could weigh 3000 lbs without a driver.
2950 
and not all that purpose built either.
Posted By: Rapid340
Re: 273 FAST cars? - 01/26/09 02:23 PM
Mine weighs 3060 and I havent done much to reduce it.
Posted By: HPMike
Re: 273 FAST cars? - 01/26/09 02:35 PM
Quote:
Quote:
I believe a purpose built FAST Duster could weigh 3000 lbs without a driver.
2950 and not all that purpose built either.
That's pretty light, indeed. With the new build you should be putting some hurt on some of the "heavies".
MB
Posted By: dannysbee
Re: 273 FAST cars? - 01/26/09 04:09 PM
My weight was just a guess so with this input from owners I would think another 100 lbs at least could come off so we are at 2850 without a driver. We are starting from scratch so lets build a 72 Demon and take advantage of the snorkle scoop for some fresh air. A 416 inch engine should be able to make 1.15 Hp per cubic inch fairly easily which is 475 flywheel Hp. So with a 200 lbs driver we have a 3050 lbs car with 475-500 Hp. Your launching this 3050 lbs car on the same tire and wheel size that HemiJoel has run 10's on in a car that weighs at least 600 lbs more than this Demon. Could get very interesting. This package with 500 Hp and a 1.60 60'might run a 10.
Posted By: HotRodDave
Re: 273 FAST cars? - 01/26/09 05:13 PM
I am thinking the early a is a little lighter and shorter wheel base.
The only other reason I am think about this car is because it is complete and would need a lot of work and not as much money as buying a complete 340 car then modyfing it.
Posted By: F1Scamp
Re: 273 FAST cars? - 01/26/09 06:43 PM
Quote:
Mine weighs 3060 and I havent done much to reduce it.
Man I can't wait to get my Duster done.
Posted By: HotRodDave
Re: 273 FAST cars? - 01/26/09 09:03 PM
How do they decide if the idle sounds stock? Do they hook up a vacume gauge?
Posted By: HotRodDave
Re: 273 FAST cars? - 01/26/09 09:09 PM
I just had another thought, I have a nice 318 short block SCAT I beams .030 KB167 pistons in my 68 cuda, has 302 heads right now. If those 273 heads are only going to flow enough to make say 450hp (could run 2.02 valves in a 318) might be just as well off useing that instead of building a huge inch motor that will make way too much tq any how. Mabey I will do some testing with that motor in that car before I yank it for it's own future stroker.
Posted By: F1Scamp
Re: 273 FAST cars? - 01/26/09 09:54 PM
Quote:
How do they decide if the idle sounds stock? Do they hook up a vacume gauge?
No vacuum gauge, it is more of an experience thing. I have heard a few cars that I and others felt didn't souund anything near stock, but it isn't up to us. I'm not sure if anyone has been called on it though.
Posted By: dannysbee
Re: 273 FAST cars? - 01/26/09 11:03 PM
I would'nt use a 340 car. I would use the straightest, rust free 6 cylinder car I could get my hands on. Strip it of all the undercoat and seam sealer. Delete the radio and heater. Bench seat auto on the column. I think you get the idea.
Posted By: CJK440
Re: 273 FAST cars? - 01/26/09 11:58 PM
Quote:
I just had another thought, I have a nice 318 short block SCAT I beams .030 KB167 pistons in my 68 cuda, has 302 heads right now. If those 273 heads are only going to flow enough to make say 450hp (could run 2.02 valves in a 318) might be just as well off useing that instead of building a huge inch motor that will make way too much tq any how. Mabey I will do some testing with that motor in that car before I yank it for it's own future stroker.
I would guess, if you wanted to keep displacement low-er due to breathing issues you would still want the bigger bores of a 340/360.
Dwayne helped me out alot with my build(s) and other guys too. For the things he mentioned a 65 Dart isn't a world beater, and in bench racing isn't the best small block combo either. But then again, if you are looking to be top dog, you're barking up the wrong tree.
There are 2 guys who checked out deep into the 10's with the next fastest quite a bit behind, but we're all in it for fun. It would be cool to see something different on the track and I guarantee you'll really enjoy being a part of it.
Posted By: CJK440
Re: 273 FAST cars? - 01/27/09 12:00 AM
Quote:
Quote:
Mine weighs 3060 and I havent done much to reduce it.
Man I can't wait to get my Duster done.
Posted By: dannysbee
Re: 273 FAST cars? - 01/27/09 02:56 AM
I lied, I would start with this one.
Posted By: dannysbee
Re: 273 FAST cars? - 01/27/09 02:59 AM
1972 340 car in Top Banana, black bench seat, auto on the column.
Posted By: HotRodDave
Re: 273 FAST cars? - 01/27/09 03:07 AM
Yes, but you still have to buy 340 ex manifolds $$$ intake manifold $$$ thermoquad $$$ air cleaner $$$ probably a few other things for a 340 car $$$
I can buy this car complete with a nice air cleaner valve covers, carb, all the 4spd stuff, I have a short block that could handle whatever the top end can throw at it. Needs lower quarter patches, paint and some interior stuff and it could be drivable.
Posted By: jyrki
Re: 273 FAST cars? - 01/27/09 08:32 AM
Still, how about the exhaust? Is it limited to a single , or are duals allowed? And '66 D-Darts had headers, but itäs a "package car", so I have no idea wether itäs allowed or not. The early Darts have 111" wheelbase, just like the newer ones, and they have a pretty long rear over hang which might be good for the weight distributiön. However, the GT is not that light. Even though they are narrower than the new ones, they aren't any lighter and the Hard Top is the heaviest of the bunch. Most competitive would propably be a '64-'66 valiant 2 D sedan, with onyl 106" wheelbase and the same drivetrain available they have considerable more potential than the 300+ lbs heavier GT Dart. A 7 1/4" with a sure grip should work at least for a while, I had one behind a 340 and a manual and couldn't kill it. the open ones are a different story, the spider gears die within a few days, and when you weld it solid, the axles will break.
Posted By: dannysbee
Re: 273 FAST cars? - 01/27/09 01:08 PM
No headers in FAST. The exhaust would have to go before the Board to see if duels would be allowed as the cars had a single exhaust from the factory.