Re: Dual Plane Intake Porting Pics
[Re: BradH]
#2896057
03/05/21 01:50 PM
03/05/21 01:50 PM
|
Joined: Feb 2016
Posts: 55 CT
roadrunner2
member
|
member
Joined: Feb 2016
Posts: 55
CT
|
So just an update and a little info about what is possible with the stock intake and exhaust manifolds. I’m replacing the 10:1 451 talked about earlier in the tread. That engine did push my 68 Road Runner to an 11.63 @ 119. The new engine is a 499” with 14:1 compression the same heads intake carb and ignition from my 451. Cam is a moderate solid roller designed by Dwayne Porter. Intake is extensively worked with the sharp turns removed and rounded. In legal form on the dyno including air cleaner but no alternator or mufflers pulled over 560 hp and over 570 ft lbs. testing spacers, carbs and other stuff I don’t want to talk about power and torque were much better. Bottom line is 600+ hp is available through the factory iron if you do it right.
Bill
1968 Road Runner 383 727 3.91 8 3/4 3520 with driver 11.04 @ 124.26 with 1.67 60’ Done on G70-14 redlines thru factory manifolds New quickest ever 383 build in FAST. 10:1 451” replaced with 14:1 499”.
|
|
|
Re: Dual Plane Intake Porting Pics
[Re: fast68plymouth]
#2896069
03/05/21 02:05 PM
03/05/21 02:05 PM
|
Joined: Jan 2004
Posts: 8,637 fredericksburg,va
cudaman1969
master
|
master
Joined: Jan 2004
Posts: 8,637
fredericksburg,va
|
I like that little lip you leave at the upper/lower plenum transition.
I don’t know if it helps or not, but I like the idea of it. Like the Hemi Vanke intake hat I’m looking to do now, pretty much cut out the same way
|
|
|
Re: Dual Plane Intake Porting Pics
[Re: polyspheric]
#2896130
03/05/21 04:31 PM
03/05/21 04:31 PM
|
Joined: Apr 2008
Posts: 117 Aus
hysteric
member
|
member
Joined: Apr 2008
Posts: 117
Aus
|
I'm curious about something else: the actual cylinder pressure. If the weakest cylinder has lower % VE, this means it will not be as "full" of mixture (same volume, lower mass) when the intake valve closes. The actual output of that cylinder will be lower. The question: are any stock manifolds so bad that this may be a problem? It might show up as a colder plug in a weak cylinder.
This where you should be looking. AFR's between cylinders can vary greatly and there is a reason factory carbs came with booster tangs to improve distribution. Something to think about: DC 34 Bulletin tech archivesLook at the booster mods for for Holley on page 20. Have fun.
|
|
|
Re: Dual Plane Intake Porting Pics
[Re: roadrunner2]
#2896165
03/05/21 06:22 PM
03/05/21 06:22 PM
|
Joined: Jan 2003
Posts: 14,531 So. Burlington, Vt.
fast68plymouth
I Live Here
|
I Live Here
Joined: Jan 2003
Posts: 14,531
So. Burlington, Vt.
|
Bottom line is 600+ hp is available through the factory iron if you do it right. So, you’re saying you saw 600+hp on the dyno while still using the reworked stock intake manifold and exhaust manifolds on the motor?
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123 Dealer for Comp Cams/Indy Heads
|
|
|
Re: Dual Plane Intake Porting Pics
[Re: parksr5]
#2896168
03/05/21 06:31 PM
03/05/21 06:31 PM
|
Joined: Oct 2007
Posts: 4,219 New York
polyspheric
master
|
master
Joined: Oct 2007
Posts: 4,219
New York
|
But... dual plane cylinder-to-cylinder (and bank-to-bank) distribution changes more than other designs: 1. with RPM 2. with engine vacuum Working to correct runners WOT at peak may give a big flat spot somewhere, fuel drop-out, black & white plugs. harder than it looks. I heard Brzezinski did good work on dual plane iron manifolds: https://tinyurl.com/y7xvcsas
Boffin Emeritus
|
|
|
Re: Dual Plane Intake Porting Pics
[Re: roadrunner2]
#2896179
03/05/21 06:52 PM
03/05/21 06:52 PM
|
Joined: Jan 2003
Posts: 18,025 S.E. Michigan
ZIPPY
I Live Here
|
I Live Here
Joined: Jan 2003
Posts: 18,025
S.E. Michigan
|
The new engine is a 499” with 14:1 compression
In other words, it's a fairly decent running 383
Rich H.
Esse Quam Videri
|
|
|
Re: Dual Plane Intake Porting Pics
[Re: ZIPPY]
#2896189
03/05/21 07:05 PM
03/05/21 07:05 PM
|
Joined: Feb 2016
Posts: 55 CT
roadrunner2
member
|
member
Joined: Feb 2016
Posts: 55
CT
|
The new engine is a 499” with 14:1 compression
In other words, it's a fairly decent running 383
1968 Road Runner 383 727 3.91 8 3/4 3520 with driver 11.04 @ 124.26 with 1.67 60’ Done on G70-14 redlines thru factory manifolds New quickest ever 383 build in FAST. 10:1 451” replaced with 14:1 499”.
|
|
|
Re: Dual Plane Intake Porting Pics
[Re: ZIPPY]
#2896199
03/05/21 07:26 PM
03/05/21 07:26 PM
|
Joined: Jan 2004
Posts: 8,637 fredericksburg,va
cudaman1969
master
|
master
Joined: Jan 2004
Posts: 8,637
fredericksburg,va
|
The new engine is a 499” with 14:1 compression
In other words, it's a fairly decent running 383 First thing I thought about that plain Jane 66 Malibo BIG cubes, 600+
|
|
|
Re: Dual Plane Intake Porting Pics
[Re: roadrunner2]
#2896425
03/06/21 11:52 AM
03/06/21 11:52 AM
|
Joined: Nov 2003
Posts: 5,160 Texas
dannysbee
master
|
master
Joined: Nov 2003
Posts: 5,160
Texas
|
Hope the new engine pays dividends. Probably not going to be as easy to hook as the old engine. Keep us updated.
Getting old just means you were smarter than some and luckier than others.
|
|
|
Re: Dual Plane Intake Porting Pics
[Re: dannysbee]
#2896602
03/06/21 09:33 PM
03/06/21 09:33 PM
|
Joined: Mar 2009
Posts: 894 Oh
parksr5
OP
super stock
|
OP
super stock
Joined: Mar 2009
Posts: 894
Oh
|
Well, a little slower than what I'd like but, I've been progressing too.
The intake I was working on, that I mentioned in this thread, is about done. I had everything finished other than the port match. I Dykam'd it up, bolted it on and wouldn't you know it, it cracked up one of the ports when I bolted it on. I finished the port match on that port and took it to a guy that has been cast iron welding since 1972 and he said no problem. The intake has been welded for a few weeks and I plan to go pick it up on Thursday.
Like roadrunner2, I too called Dwayne for a custom ground cam but, mine is a solid flat tappet.
I took the heads back to K&G to be set up for the new cam, they are ready and I'll pick those up on Thursday too.
Hope to have the engine back together in the next month or so.
If everything goes as planned, I plan on breaking the new cam in on an engine dyno and making some pulls.
With the info roadrunner2 provided, it will be interesting to see the differences between a pretty mild combo like mine and what he has. Mine's 470 inches, only around 9.35:1 and again, a solid flat tappet. Everything else should be comparable; well, probably not the intake, sounds like some major voodoo going on there.
Last edited by parksr5; 03/06/21 10:34 PM.
|
|
|
Re: Dual Plane Intake Porting Pics
[Re: parksr5]
#2896724
03/07/21 11:45 AM
03/07/21 11:45 AM
|
Joined: Nov 2020
Posts: 349 Isle of Sheeps
Gtxxjon
enthusiast
|
enthusiast
Joined: Nov 2020
Posts: 349
Isle of Sheeps
|
Nice thread GUYS! Loving all the stock talk, just like in the 60' lol... We have a Superstock class in the UK thats pretty free thinking... Gonna run my 440 71 GTX with a sixpack iron manifold, originally a iron 4bbl with a Thermoquad. I know its cheating but I'm up against guys with 572 KB hemi's with twin dominators... (Yep they call that Superstock over here)
Last edited by Gtxxjon; 03/07/21 11:46 AM.
Carpe diem, quam minimum credula postero, thanx Horace!
There’s no point trying to fix stuff that ain’t broke,,, 'but if ain’t broke',,, you is not trying hard enough...
|
|
|
Re: Dual Plane Intake Porting Pics
[Re: roadrunner2]
#2898541
03/12/21 06:55 PM
03/12/21 06:55 PM
|
Joined: Jan 2003
Posts: 18,025 S.E. Michigan
ZIPPY
I Live Here
|
I Live Here
Joined: Jan 2003
Posts: 18,025
S.E. Michigan
|
The new engine is a 499” with 14:1 compression
In other words, it's a fairly decent running 383 Just as expected
Rich H.
Esse Quam Videri
|
|
|
Re: Dual Plane Intake Porting Pics
[Re: parksr5]
#2983149
11/08/21 05:11 PM
11/08/21 05:11 PM
|
Joined: Feb 2016
Posts: 55 CT
roadrunner2
member
|
member
Joined: Feb 2016
Posts: 55
CT
|
Well, a little slower than what I'd like but, I've been progressing too.
The intake I was working on, that I mentioned in this thread, is about done. I had everything finished other than the port match. I Dykam'd it up, bolted it on and wouldn't you know it, it cracked up one of the ports when I bolted it on. I finished the port match on that port and took it to a guy that has been cast iron welding since 1972 and he said no problem. The intake has been welded for a few weeks and I plan to go pick it up on Thursday.
Like roadrunner2, I too called Dwayne for a custom ground cam but, mine is a solid flat tappet.
I took the heads back to K&G to be set up for the new cam, they are ready and I'll pick those up on Thursday too.
Hope to have the engine back together in the next month or so.
If everything goes as planned, I plan on breaking the new cam in on an engine dyno and making some pulls.
With the info roadrunner2 provided, it will be interesting to see the differences between a pretty mild combo like mine and what he has. Mine's 470 inches, only around 9.35:1 and again, a solid flat tappet. Everything else should be comparable; well, probably not the intake, sounds like some major voodoo going on there. Any updates on your build this year?
1968 Road Runner 383 727 3.91 8 3/4 3520 with driver 11.04 @ 124.26 with 1.67 60’ Done on G70-14 redlines thru factory manifolds New quickest ever 383 build in FAST. 10:1 451” replaced with 14:1 499”.
|
|
|
Re: Dual Plane Intake Porting Pics
[Re: roadrunner2]
#2983348
11/09/21 09:45 AM
11/09/21 09:45 AM
|
Joined: Mar 2009
Posts: 894 Oh
parksr5
OP
super stock
|
OP
super stock
Joined: Mar 2009
Posts: 894
Oh
|
Unfortunately, or fortunately, depending on how you look at it, when I took the old cam out, I found 2 cam bearings that were trashed; 1 looked like it could have spun at any point.
I took the short block to the machine shop for a freshen up, where it has sat the whole year. I talked to the shop owner in September and he said he'd call me in October to discuss a game plan; I haven't heard from him and really need to call to check in.
The shop owner has other business ventures and some areas of his businesses were crippled this year by all the Covid fall out. To be clear, I'm not upset with him at all, it's happened to so many.
I've been busy with a kitchen remodel and other house updates, so; I've not been too worried about it because I've got so many other things that are consuming my time right now. I'm starting to itch to get the engine stuff all taken care of though.
Minus any new bearings or rings, I have everything to put it back together, so; I would assume that once the machine work is done, it should be relatively quick.
What was your fastest time with the new setup this year?
|
|
|
Re: Dual Plane Intake Porting Pics
[Re: parksr5]
#2983414
11/09/21 01:21 PM
11/09/21 01:21 PM
|
Joined: Feb 2016
Posts: 55 CT
roadrunner2
member
|
member
Joined: Feb 2016
Posts: 55
CT
|
I ran the old motor again this year (451” 10:1). It did improve to an 11.51 @ 119.78 besting all the 383builds before it. New motor spun a bearing on its first outing. Culprit was loose lifter galleys and a too inattentive driver. Once it got warm the oil pressure went down the drain. Maybe I’ll get it out next year, maybe I’ll work on putting the little motor into the 11.20s.
Bill
1968 Road Runner 383 727 3.91 8 3/4 3520 with driver 11.04 @ 124.26 with 1.67 60’ Done on G70-14 redlines thru factory manifolds New quickest ever 383 build in FAST. 10:1 451” replaced with 14:1 499”.
|
|
|
Re: Dual Plane Intake Porting Pics
[Re: parksr5]
#2983730
11/10/21 08:30 AM
11/10/21 08:30 AM
|
Joined: Feb 2016
Posts: 55 CT
roadrunner2
member
|
member
Joined: Feb 2016
Posts: 55
CT
|
Thanks guys. I’ve worked hard on this car. Had to as I’m mentally unable to work smart. Ram a bunch of 11.5 ET at the FAST race at MIR but couldn’t get a decent 60’. Replaced the rear shocks and am heading to Cecil county on the 20th to see it I can put a complete run together.
1968 Road Runner 383 727 3.91 8 3/4 3520 with driver 11.04 @ 124.26 with 1.67 60’ Done on G70-14 redlines thru factory manifolds New quickest ever 383 build in FAST. 10:1 451” replaced with 14:1 499”.
|
|
|
|
|