Previous Thread
Next Thread
Print Thread
Page 1 of 2 1 2
Piston depth in hole - '69 Roadrunner #2805504
08/05/20 05:56 PM
08/05/20 05:56 PM
Joined: Mar 2003
Posts: 4,915
Tri-Cities, Washington
V
VITC_GTX Offline OP
master
VITC_GTX  Offline OP
master
V

Joined: Mar 2003
Posts: 4,915
Tri-Cities, Washington
OK, I know that piston choice sucks for the 383 with stock heads but my best option seems to be the Speed Pro 2315. I have been told that these have a slightly shorter compression height than stock (~.014"). So that will put this piston ~.014" further down in the hole than my stock pistons.

Million dollar question: How far down in the hole are my stock '69 383 pistons in my Roadrunner?

Now, I know what some will say... "there all over the map!!" and I understand that I'm just looking for an average WAG, .005", .020" or ???

Re: Piston depth in hole - '69 Roadrunner [Re: VITC_GTX] #2805507
08/05/20 06:15 PM
08/05/20 06:15 PM
Joined: Nov 2007
Posts: 21,808
Kirkland, Washington
Pacnorthcuda Offline
Too Many Posts
Pacnorthcuda  Offline
Too Many Posts

Joined: Nov 2007
Posts: 21,808
Kirkland, Washington
A lot of them are 20-40 in the hole stock. Some even more. I sure wouldn’t make any big decisions till pulling the heads.

Re: Piston depth in hole - '69 Roadrunner [Re: Pacnorthcuda] #2805509
08/05/20 06:26 PM
08/05/20 06:26 PM
Joined: Mar 2003
Posts: 4,915
Tri-Cities, Washington
V
VITC_GTX Offline OP
master
VITC_GTX  Offline OP
master
V

Joined: Mar 2003
Posts: 4,915
Tri-Cities, Washington
Originally Posted by Pacnorthcuda
A lot of them are 20-40 in the hole stock. Some even more. I sure wouldn’t make any big decisions till pulling the heads.


Stock pistons at .040" in the hole would put the currnet engine at about 8.5:1 compression (assuming 90cc heads).

Last edited by VITC_GTX; 08/05/20 06:27 PM.
Re: Piston depth in hole - '69 Roadrunner [Re: VITC_GTX] #2805515
08/05/20 06:51 PM
08/05/20 06:51 PM
Joined: Jun 2008
Posts: 3,913
usa
L
lewtot184 Offline
master
lewtot184  Offline
master
L

Joined: Jun 2008
Posts: 3,913
usa
the stock pistons in my '68 road runner were very close to zero deck with nothing touched. 2315's will be close to .010" below the deck.

Re: Piston depth in hole - '69 Roadrunner [Re: lewtot184] #2805518
08/05/20 07:04 PM
08/05/20 07:04 PM
Joined: Aug 2011
Posts: 2,842
Pattison Texas
CSK Offline
master
CSK  Offline
master

Joined: Aug 2011
Posts: 2,842
Pattison Texas
Originally Posted by lewtot184
the stock pistons in my '68 road runner were very close to zero deck with nothing touched. 2315's will be close to .010" below the deck.


I have never seen off the shelf pistons for a 383 that was .010 below, they have been .040 or more that I have seen

Check this
CLICKHERE

Last edited by csk; 08/05/20 07:08 PM.

1968 Charger COLD A/C Hilborn EFI
512ci 9.7 compression, Stealth heads, 4.10 gear A518 ODtrans 4100lb,10.93 full street car trim
2020 T/A 392 Stock 11.79 @ 114.5

Re: Piston depth in hole - '69 Roadrunner [Re: lewtot184] #2805565
08/05/20 09:17 PM
08/05/20 09:17 PM
Joined: Aug 2005
Posts: 299
Hinckley, Ohio
KWF340 Offline
enthusiast
KWF340  Offline
enthusiast

Joined: Aug 2005
Posts: 299
Hinckley, Ohio
Originally Posted by lewtot184
the stock pistons in my '68 road runner were very close to zero deck with nothing touched. 2315's will be close to .010" below the deck.


Same here. The stock pistons in my '69 Bee were about .005 in the hole.


1968 Charger R/T, 440 Auto, GG1;
1969 Super Bee, 383, 4-speed, T5;
1969.5 Road Runner, 440-6, 4-speed, 96;
1970 Duster 340, 4-speed, EV2;
1970 Charger R/T SE, 440 (496), Auto, EB3;
1970 Dart Swinger 340 (416), 4-speed, EV2;
1970 Corvette coupe, LS5, 4-speed, Daytona yellow;
2000 Corvette coupe, LS1, 6-speed, Twin Turbo, Torch red.
Re: Piston depth in hole - '69 Roadrunner [Re: CSK] #2805567
08/05/20 09:19 PM
08/05/20 09:19 PM
Joined: Jun 2008
Posts: 3,913
usa
L
lewtot184 Offline
master
lewtot184  Offline
master
L

Joined: Jun 2008
Posts: 3,913
usa
Originally Posted by csk
Originally Posted by lewtot184
the stock pistons in my '68 road runner were very close to zero deck with nothing touched. 2315's will be close to .010" below the deck.


I have never seen off the shelf pistons for a 383 that was .010 below, they have been .040 or more that I have seen

Check this
CLICKHERE
stock '68's were +.020" out of the hole when decked to nhra specs. the 2315's I did for a friend were about .010" below the deck in a stock un-milled block. IIRC the '68 piston has a 1.935 pin height. KB's are 1.908, 2315's are 1.915 IIRC, generic 8:1's are 1.86 IIRC.

Re: Piston depth in hole - '69 Roadrunner [Re: CSK] #2805569
08/05/20 09:22 PM
08/05/20 09:22 PM
Joined: Aug 2005
Posts: 299
Hinckley, Ohio
KWF340 Offline
enthusiast
KWF340  Offline
enthusiast

Joined: Aug 2005
Posts: 299
Hinckley, Ohio
Originally Posted by csk
Originally Posted by lewtot184
the stock pistons in my '68 road runner were very close to zero deck with nothing touched. 2315's will be close to .010" below the deck.


I have never seen off the shelf pistons for a 383 that was .010 below, they have been .040 or more that I have seen

Check this
CLICKHERE


Compression height on a stock 383 piston is 1.934 (for '68 and '69). The compression height for the speed pro 2315 pistons is 1.92.

2315 link.

So if no machine work is done the 2315s will be .014 further in the hole than the stock pistons.

Last edited by KWF340; 08/05/20 09:26 PM.

1968 Charger R/T, 440 Auto, GG1;
1969 Super Bee, 383, 4-speed, T5;
1969.5 Road Runner, 440-6, 4-speed, 96;
1970 Duster 340, 4-speed, EV2;
1970 Charger R/T SE, 440 (496), Auto, EB3;
1970 Dart Swinger 340 (416), 4-speed, EV2;
1970 Corvette coupe, LS5, 4-speed, Daytona yellow;
2000 Corvette coupe, LS1, 6-speed, Twin Turbo, Torch red.
Re: Piston depth in hole - '69 Roadrunner [Re: lewtot184] #2805627
08/06/20 01:48 AM
08/06/20 01:48 AM
Joined: Aug 2011
Posts: 2,842
Pattison Texas
CSK Offline
master
CSK  Offline
master

Joined: Aug 2011
Posts: 2,842
Pattison Texas
Originally Posted by lewtot184
Originally Posted by csk
Originally Posted by lewtot184
the stock pistons in my '68 road runner were very close to zero deck with nothing touched. 2315's will be close to .010" below the deck.


I have never seen off the shelf pistons for a 383 that was .010 below, they have been .040 or more that I have seen

Check this
CLICKHERE
stock '68's were +.020" out of the hole when decked to nhra specs. the 2315's I did for a friend were about .010" below the deck in a stock un-milled block. IIRC the '68 piston has a 1.935 pin height. KB's are 1.908, 2315's are 1.915 IIRC, generic 8:1's are 1.86 IIRC.


I knew the hp 68.69 had + or close deck, I was referring to replacement pistons [Shelf pistons] that said I still dont recall the 2315 being that close to the deck, BUT I have been wrong at least once in my life. smile


1968 Charger COLD A/C Hilborn EFI
512ci 9.7 compression, Stealth heads, 4.10 gear A518 ODtrans 4100lb,10.93 full street car trim
2020 T/A 392 Stock 11.79 @ 114.5

Re: Piston depth in hole - '69 Roadrunner [Re: CSK] #2805632
08/06/20 05:50 AM
08/06/20 05:50 AM
Joined: Jun 2008
Posts: 3,913
usa
L
lewtot184 Offline
master
lewtot184  Offline
master
L

Joined: Jun 2008
Posts: 3,913
usa
Originally Posted by csk
Originally Posted by lewtot184
Originally Posted by csk
Originally Posted by lewtot184
the stock pistons in my '68 road runner were very close to zero deck with nothing touched. 2315's will be close to .010" below the deck.


I have never seen off the shelf pistons for a 383 that was .010 below, they have been .040 or more that I have seen

Check this
CLICKHERE
stock '68's were +.020" out of the hole when decked to nhra specs. the 2315's I did for a friend were about .010" below the deck in a stock un-milled block. IIRC the '68 piston has a 1.935 pin height. KB's are 1.908, 2315's are 1.915 IIRC, generic 8:1's are 1.86 IIRC.


I knew the hp 68.69 had + or close deck, I was referring to replacement pistons [Shelf pistons] that said I still dont recall the 2315 being that close to the deck, BUT I have been wrong at least once in my life. smile
I was surprised at the deck height with the 2315. they would make a good street performance piston with zero deck easy; down side no valve reliefs. pretty sure the '68-'69 piston is no longer available.

Re: Piston depth in hole - '69 Roadrunner [Re: lewtot184] #2805645
08/06/20 07:43 AM
08/06/20 07:43 AM
Joined: Jan 2003
Posts: 6,363
Abilene, Texas
F
fastmark Offline
master
fastmark  Offline
master
F

Joined: Jan 2003
Posts: 6,363
Abilene, Texas
I’m not finished with the build yet but I’m building a 66 383 right now with 452 heads. It had kB pistons in it. They are way down the hole with Grand Canyon valve reliefs. I can remember the exact specs right now but they are written down on my build sheet at the shop. The compression ratio was way low. I bought the sealed power 2315s as replacements. My machine shop had to equalize the deck because they appeared to have been mill slightly off previously. He did not take much off to correct it. Knowing how these blocks can shift around with heating and cooling cycles, it may not have been milled at all. I have only installed one piston to degree the cam and check valve to piston clearance with my choice of cam. From my memory right now, I think my final deck height was-.006. I’ll double check, I’ve got three builds going right now. Going from my pre-build notes, this should bring a compression ration of 9.0:1. I had plenty of piston the valve clearance with comp camps 262H cam. I’ll post the lift and duration numbers later today.

Re: Piston depth in hole - '69 Roadrunner [Re: fastmark] #2805675
08/06/20 09:49 AM
08/06/20 09:49 AM
Joined: Mar 2003
Posts: 4,915
Tri-Cities, Washington
V
VITC_GTX Offline OP
master
VITC_GTX  Offline OP
master
V

Joined: Mar 2003
Posts: 4,915
Tri-Cities, Washington
Great information guys. Thanks!

Re: Piston depth in hole - '69 Roadrunner [Re: VITC_GTX] #2805684
08/06/20 10:17 AM
08/06/20 10:17 AM
Joined: Jan 2003
Posts: 10,666
North Dakota
6PakBee Offline
I Live Here
6PakBee  Offline
I Live Here

Joined: Jan 2003
Posts: 10,666
North Dakota
You may want to talk to member mike s. IIRC he had zero deck 383 pistons available.


"We live in a time when intelligent people are being silenced so that stupid people won't be offended".
Re: Piston depth in hole - '69 Roadrunner [Re: VITC_GTX] #2805713
08/06/20 11:46 AM
08/06/20 11:46 AM
Joined: Feb 2005
Posts: 4,309
Prospect, PA
BSB67 Offline
master
BSB67  Offline
master

Joined: Feb 2005
Posts: 4,309
Prospect, PA
Originally Posted by VITC_GTX
OK, I know that piston choice sucks for the 383 with stock heads but my best option seems to be the Speed Pro 2315. I have been told that these have a slightly shorter compression height than stock (~.014"). So that will put this piston ~.014" further down in the hole than my stock pistons.

Million dollar question: How far down in the hole are my stock '69 383 pistons in my Roadrunner?

Now, I know what some will say... "there all over the map!!" and I understand that I'm just looking for an average WAG, .005", .020" or ???


Piston choice does not suck.

The 2315 is a good replacement. Depending on what your goal is, you can get it to zero deck pretty easy and use a aftermarket head of your choosing and have good quench with a 0.040" head gasket. Or cut less, and use a thinner gasket to get the quench. Valve to piston will become an issue with bigger cams.

The best piston IMO is the ICON IC687. It will requiring decking to get it to zero (if that's what you want) but has valve reliefs and a slight dome (4.5 cc) so you can get to 9.5 CR easily and not worry about piston to valve.

I've owned and have been around several 68/69 383s. They come in betweem zero (0.000") and 0.005" below the deck.

Re: Piston depth in hole - '69 Roadrunner [Re: VITC_GTX] #2805716
08/06/20 11:56 AM
08/06/20 11:56 AM
Joined: Jan 2003
Posts: 24,562
Brookeville, Md
Mr.Yuck Offline
Not enough dumb comments...yet
Mr.Yuck  Offline
Not enough dumb comments...yet

Joined: Jan 2003
Posts: 24,562
Brookeville, Md
why not just call Diamond and have a set made?


[IMG]http://i66.tinypic.com/pui5j.jpg[/IMG]
Coming soon!!!!
Re: Piston depth in hole - '69 Roadrunner [Re: Mr.Yuck] #2805718
08/06/20 12:04 PM
08/06/20 12:04 PM
Joined: Feb 2005
Posts: 4,309
Prospect, PA
BSB67 Offline
master
BSB67  Offline
master

Joined: Feb 2005
Posts: 4,309
Prospect, PA
Originally Posted by Mr.Yuck
why not just call Diamond and have a set made?


Mostly becaust for what the OP is doing, it would not be any better than the IC687, and probably cost almost twice as much.

Re: Piston depth in hole - '69 Roadrunner [Re: BSB67] #2805759
08/06/20 01:50 PM
08/06/20 01:50 PM
Joined: May 2012
Posts: 1,811
South Bend
John Brown Offline
top fuel
John Brown  Offline
top fuel

Joined: May 2012
Posts: 1,811
South Bend
Originally Posted by BSB67
Originally Posted by VITC_GTX
OK, I know that piston choice sucks for the 383 with stock heads but my best option seems to be the Speed Pro 2315. I have been told that these have a slightly shorter compression height than stock (~.014"). So that will put this piston ~.014" further down in the hole than my stock pistons.

Million dollar question: How far down in the hole are my stock '69 383 pistons in my Roadrunner?

Now, I know what some will say... "there all over the map!!" and I understand that I'm just looking for an average WAG, .005", .020" or ???


Piston choice does not suck.

The 2315 is a good replacement. Depending on what your goal is, you can get it to zero deck pretty easy and use a aftermarket head of your choosing and have good quench with a 0.040" head gasket. Or cut less, and use a thinner gasket to get the quench. Valve to piston will become an issue with bigger cams.

The best piston IMO is the ICON IC687. It will requiring decking to get it to zero (if that's what you want) but has valve reliefs and a slight dome (4.5 cc) so you can get to 9.5 CR easily and not worry about piston to valve.

I've owned and have been around several 68/69 383s. They come in betweem zero (0.000") and 0.005" below the deck.


Good to know. thumbs


July 19th should be "Drive Like Rockford Day". R.I.P. Jimmie.
Re: Piston depth in hole - '69 Roadrunner [Re: BSB67] #2805780
08/06/20 02:36 PM
08/06/20 02:36 PM
Joined: Mar 2003
Posts: 4,915
Tri-Cities, Washington
V
VITC_GTX Offline OP
master
VITC_GTX  Offline OP
master
V

Joined: Mar 2003
Posts: 4,915
Tri-Cities, Washington
Originally Posted by BSB67
Originally Posted by VITC_GTX
OK, I know that piston choice sucks for the 383 with stock heads but my best option seems to be the Speed Pro 2315. I have been told that these have a slightly shorter compression height than stock (~.014"). So that will put this piston ~.014" further down in the hole than my stock pistons.

Million dollar question: How far down in the hole are my stock '69 383 pistons in my Roadrunner?

Now, I know what some will say... "there all over the map!!" and I understand that I'm just looking for an average WAG, .005", .020" or ???


Piston choice does not suck.

The 2315 is a good replacement. Depending on what your goal is, you can get it to zero deck pretty easy and use a aftermarket head of your choosing and have good quench with a 0.040" head gasket. Or cut less, and use a thinner gasket to get the quench. Valve to piston will become an issue with bigger cams.

The best piston IMO is the ICON IC687. It will requiring decking to get it to zero (if that's what you want) but has valve reliefs and a slight dome (4.5 cc) so you can get to 9.5 CR easily and not worry about piston to valve.

I've owned and have been around several 68/69 383s. They come in betweem zero (0.000") and 0.005" below the deck.


My engine is matching numbers so I don't want to deck the block and loose the numbers on the pad. Even without decking these pistons show a bump of about 0.2:1 over the 2315's. Definitely an option.

Re: Piston depth in hole - '69 Roadrunner [Re: VITC_GTX] #2805848
08/06/20 04:42 PM
08/06/20 04:42 PM
Joined: Jan 2004
Posts: 8,192
fredericksburg,va
C
cudaman1969 Offline
master
cudaman1969  Offline
master
C

Joined: Jan 2004
Posts: 8,192
fredericksburg,va
Go to class racer.com, register, then go to 1969 383 RR blueprint specs. All the pistons they show are good ones that will be up at the deck, all have 5/64 rings but thin ring packages are available $$. If using high lift or long duration cam it will need valve reliefs.

Re: Piston depth in hole - '69 Roadrunner [Re: VITC_GTX] #2805921
08/06/20 09:04 PM
08/06/20 09:04 PM
Joined: Jun 2008
Posts: 3,913
usa
L
lewtot184 Offline
master
lewtot184  Offline
master
L

Joined: Jun 2008
Posts: 3,913
usa
Originally Posted by VITC_GTX
Originally Posted by BSB67
Originally Posted by VITC_GTX
OK, I know that piston choice sucks for the 383 with stock heads but my best option seems to be the Speed Pro 2315. I have been told that these have a slightly shorter compression height than stock (~.014"). So that will put this piston ~.014" further down in the hole than my stock pistons.

Million dollar question: How far down in the hole are my stock '69 383 pistons in my Roadrunner?

Now, I know what some will say... "there all over the map!!" and I understand that I'm just looking for an average WAG, .005", .020" or ???


Piston choice does not suck.

The 2315 is a good replacement. Depending on what your goal is, you can get it to zero deck pretty easy and use a aftermarket head of your choosing and have good quench with a 0.040" head gasket. Or cut less, and use a thinner gasket to get the quench. Valve to piston will become an issue with bigger cams.

The best piston IMO is the ICON IC687. It will requiring decking to get it to zero (if that's what you want) but has valve reliefs and a slight dome (4.5 cc) so you can get to 9.5 CR easily and not worry about piston to valve.

I've owned and have been around several 68/69 383s. They come in betweem zero (0.000") and 0.005" below the deck.


My engine is matching numbers so I don't want to deck the block and loose the numbers on the pad. Even without decking these pistons show a bump of about 0.2:1 over the 2315's. Definitely an option.
I did a matching numbers 383 a few years ago and didn't want to mill the block although it really needed it. used the 2315 piston with 84cc 906's and a fel pro 8519 gasket. also used a summit 6400 cam, stock intake/carb, re-curved stock distributor. no detonation and drives very nicely.

Page 1 of 2 1 2






Powered by UBB.threads™ PHP Forum Software 7.7.1