Pure stock 340 Mopar

Todd Boyer · 02-04-2012, 08:12 PM

Just wondering if anyone is running the 340/275 (AVS) in Pure Stock? Some time ago I remember someone running a '71 Demon 340/275 (TQ) as a Pure Stocker, and would appreciate any info I can glean.

I may initially build my '69 Dart as a Pure Stocker to get my feet wet in our local Stock/Super Stock series, then work my way up ($$$$$) and build it as a traditional Stocker.

mike coates · 02-04-2012, 09:29 PM

I have a '70 340 Dart Swinger that I run in Pure Stock. I can help out as much as possible, though my experience is limited. I didn't run last year, and only once the year before. limited time and resources lately. I just went through it last year so I hope to run a little more this year. I barely run the index, but I built everything myself.
PM me and we can talk.
Mike

I run D/PS, have run under 3914 and 5914

1971ls6 · 02-04-2012, 11:19 PM

In pure stock, you must run manifolds and polyglas tires, no port work of any kind, 2 1/2 exhaust with H or X pipe

Tom cannon runs a 71 with that carb in pure stock

Todd Boyer · 02-05-2012, 09:23 AM

1971ls6: I believe you're referring to the "Pure Stock Musclecar Drags" series in which you must run manifolds and bias tires.

Mark: IHRA has a Pure Stock class that NHRA doesn't. Our local series runs under IHRA rules which open things up to more participation from 'different' classes. You can't use a 'stocker cam' as a traditional stocker can. But I've read here that you should have a cam ground which will check within the specs but should work better than a dead stock grind.

Can run headers with mufflers OR open manifolds.

You can check out the rule book at http://www.ihra.com/.

Thanks for the replies guys.

X-TECH MAN · 02-05-2012, 12:24 PM

Quote:

Originally Posted by Todd Boyer

1971ls6: I believe you're referring to the "Pure Stock Musclecar Drags" series in which you must run manifolds and bias tires.

Mark: IHRA has a Pure Stock class that NHRA doesn't. Our local series runs under IHRA rules which open things up to more participation from 'different' classes. You can't use a 'stocker cam' as a traditional stocker can. But I've read here that you should have a cam ground which will check within the specs but should work better than a dead stock grind.

Can run headers with mufflers OR open manifolds.

You can check out the rule book at http://www.ihra.com/.

Thanks for the replies guys.

Correct on all the above. You can run 9 inch slicks at 29.5 diameter. The cam MUST check on OEM duration and over lap like in the Jr. stock days of pre 1972. The valve springs must check on OEM open and close pressure specs also.
Just pretend your racing back in 1971 Jr. stock days if your old enough to remember those days.

KRatcliff · 02-05-2012, 12:56 PM

Is there a list of the current Pure Stock records?

Mike Carr · 02-05-2012, 02:46 PM

Quote:

Originally Posted by Todd Boyer

Just wondering if anyone is running the 340/275 (AVS) in Pure Stock? Some time ago I remember someone running a '71 Demon 340/275 (TQ) as a Pure Stocker, and would appreciate any info I can glean.

I may initially build my '69 Dart as a Pure Stocker to get my feet wet in our local Stock/Super Stock series, then work my way up ($$$$$) and build it as a traditional Stocker.

Jerry Coblentz from eastern Ohio runs a Demo in C/PS, I believe it's the 340/275. I'm unsure of the IHRA rating, I think it's 310.

Todd Boyer · 02-05-2012, 10:58 PM

Quote:

Originally Posted by A56

Not old enough, im only 43. You need to put a small header on the car to draw as much air into the engine with a cam like that, your lucky though the 340 had a pretty decent cam though. 1 1/2" - 1 5/8" - 1 3/4" Merge Collectors to dual 2 1/2" with an X pipe. Maybe that will be of some help. Sounds like a fun class, wish I had the chance to give it a go.

Mark Lelchook
F/SA #704

Mark, I already have a set of 1 3/4 non-step headers, will I be able to get away with using them with the X pipe and mufflers ??? I'm only 43 also !!!

mike coates · 02-06-2012, 11:31 AM

Todd,
I have been running 1 3/4 headers on mine with flow master mufflers.
I don't have a cross over pipe. My thought was run the larger pipes since the muffler was required and will create some back pressure.
I haven't done any additional testing with smaller hearders or X pipe.

Mike

Todd Boyer · 02-06-2012, 06:37 PM

The worst part of this whole deal is that I just sold a set of Hooker 1 5/8" street & strip headers that I think may have worked with this combo. The main reason I'm wondering if the 1 3/4" will work is that I already have them, and will run them when I eventually build the car into a traditional stocker.
Like Mike, my thoughts were that I could get away with the larger pipes with the exhaust system creating at least some back pressure. Mark, I know you're the man for headers, so in all honesty, what kind of ET difference can I expect between the 1 5/8 and 1 3/4 pipes?
For our local series, I'd be really happy to be -.2 or .3.
I used to run my street/strip '69 Dart with a very mild 360, 904 with 3400 stall converter with 4.10s on 26" slicks. It went a best of 12.9 @ 105 (it was a street and strip car). The car had full exhaust including tailpipes and OLD Dynamax mufflers.

02-04-2012, 08:12 PM	#1
Todd Boyer Senior Member Join Date: Feb 2004 Location: Saint John NB Canada Posts: 560 Likes: 27 Liked 6 Times in 5 Posts	Pure stock 340 Mopar Just wondering if anyone is running the 340/275 (AVS) in Pure Stock? Some time ago I remember someone running a '71 Demon 340/275 (TQ) as a Pure Stocker, and would appreciate any info I can glean. I may initially build my '69 Dart as a Pure Stocker to get my feet wet in our local Stock/Super Stock series, then work my way up ($$$$$) and build it as a traditional Stocker.

02-04-2012, 09:29 PM	#2
mike coates Junior Member Join Date: Jul 2007 Location: Marshall, MI Posts: 31 Likes: 0 Liked 0 Times in 0 Posts	Re: Pure stock 340 Mopar I have a '70 340 Dart Swinger that I run in Pure Stock. I can help out as much as possible, though my experience is limited. I didn't run last year, and only once the year before. limited time and resources lately. I just went through it last year so I hope to run a little more this year. I barely run the index, but I built everything myself. PM me and we can talk. Mike I run D/PS, have run under 3914 and 5914 __________________ Mike Coates TBD

02-04-2012, 11:19 PM	#3
1971ls6 Junior Member Join Date: Jan 2011 Posts: 3 Likes: 0 Liked 0 Times in 0 Posts	Re: Pure stock 340 Mopar In pure stock, you must run manifolds and polyglas tires, no port work of any kind, 2 1/2 exhaust with H or X pipe Tom cannon runs a 71 with that carb in pure stock

02-05-2012, 09:23 AM	#4
Todd Boyer Senior Member Join Date: Feb 2004 Location: Saint John NB Canada Posts: 560 Likes: 27 Liked 6 Times in 5 Posts	Re: Pure stock 340 Mopar 1971ls6: I believe you're referring to the "Pure Stock Musclecar Drags" series in which you must run manifolds and bias tires. Mark: IHRA has a Pure Stock class that NHRA doesn't. Our local series runs under IHRA rules which open things up to more participation from 'different' classes. You can't use a 'stocker cam' as a traditional stocker can. But I've read here that you should have a cam ground which will check within the specs but should work better than a dead stock grind. Can run headers with mufflers OR open manifolds. You can check out the rule book at http://www.ihra.com/. Thanks for the replies guys. Last edited by Todd Boyer; 02-05-2012 at 09:32 AM. Reason: added material

02-05-2012, 12:56 PM	#6
KRatcliff Senior Member Join Date: Sep 2011 Posts: 753 Likes: 74 Liked 502 Times in 135 Posts	Re: Pure stock 340 Mopar Is there a list of the current Pure Stock records?

02-06-2012, 11:31 AM	#9
mike coates Junior Member Join Date: Jul 2007 Location: Marshall, MI Posts: 31 Likes: 0 Liked 0 Times in 0 Posts	Re: Pure stock 340 Mopar Todd, I have been running 1 3/4 headers on mine with flow master mufflers. I don't have a cross over pipe. My thought was run the larger pipes since the muffler was required and will create some back pressure. I haven't done any additional testing with smaller hearders or X pipe. Mike __________________ Mike Coates TBD

02-06-2012, 06:37 PM	#10
Todd Boyer Senior Member Join Date: Feb 2004 Location: Saint John NB Canada Posts: 560 Likes: 27 Liked 6 Times in 5 Posts	Re: Pure stock 340 Mopar The worst part of this whole deal is that I just sold a set of Hooker 1 5/8" street & strip headers that I think may have worked with this combo. The main reason I'm wondering if the 1 3/4" will work is that I already have them, and will run them when I eventually build the car into a traditional stocker. Like Mike, my thoughts were that I could get away with the larger pipes with the exhaust system creating at least some back pressure. Mark, I know you're the man for headers, so in all honesty, what kind of ET difference can I expect between the 1 5/8 and 1 3/4 pipes? For our local series, I'd be really happy to be -.2 or .3. I used to run my street/strip '69 Dart with a very mild 360, 904 with 3400 stall converter with 4.10s on 26" slicks. It went a best of 12.9 @ 105 (it was a street and strip car). The car had full exhaust including tailpipes and OLD Dynamax mufflers.