|
Re: Help me with 383 upgrade!
[Re: JohnRR]
#210657
02/18/09 06:40 AM
02/18/09 06:40 AM
|
Joined: Jun 2005
Posts: 426
Califor-ni-A!
MrFoFody
mopar
|
mopar
Joined: Jun 2005
Posts: 426
Califor-ni-A!
|
Quote:
Quote:
AS others have pointed out, don't go to big on the cam. When I rebuilt (re-ringed) my 383 a couple of years back, I put in the 509 because I wanted that prostock idle and I wanted to kill a little torque for the street (4spd, less wheel spin). It was fun romping around with that choppy idle but the power band dosn't kick in untill around 3000rpms.
My build is:
-.040 383 w/factory style flat tops & slighty decked. 9.10 calculated compression.
-516 heads, 2.14-1.81 valves, bowls ported and blended & straightened out exhaust ports. cced @ 72cc. Shim gaskets
-Holly SD w/800dp I know it's too big but all I had available and some old school Jardine headers.
The car has a 4spd and 3.91 gears so it makes the cam livable on the street. I'm either going to change the cam to a 528 solid or swap the gears to 4.30-4.56 for some extra zip in the street light grand prix. 
I'd swap in the .528 first . 
sorry for all the posts , I was out of town over the weekend and had limited computer access ...
Yea, I figured it would be better to run the 528 for a more balanced all-around combo. Although the 4.30-4.56 swap might make it a little more interesting around town...... 
|
|
|
Re: Help me with 383 upgrade!
[Re: cdp]
#210658
02/18/09 10:23 AM
02/18/09 10:23 AM
|
Joined: Jan 2003
Posts: 74,992
U.S.S.A.
JohnRR
I Win
|
I Win
Joined: Jan 2003
Posts: 74,992
U.S.S.A.
|
Quote:
So how over inflated did this article turn out to be? 40-50 horse?
number I think I heard on the dyno numbers was I think 10% ???
How high is this engine ???
I have to go thru my stash of mags to find the original build , I think the compression is lower than claimed ...
|
|
|
Re: Help me with 383 upgrade!
[Re: gch]
#210661
02/25/09 09:04 AM
02/25/09 09:04 AM
|
Joined: Nov 2004
Posts: 843
Suffolk,VA
ireland383
OP
super stock
|
OP
super stock
Joined: Nov 2004
Posts: 843
Suffolk,VA
|
No I have'nt had them milled yet. On this chart for 71 it shows them at 79.5cc already www.cowtownmopars.com. Casting # is 3462346.
|
|
|
Re: Help me with 383 upgrade!
[Re: ireland383]
#210662
02/25/09 09:55 AM
02/25/09 09:55 AM
|
Joined: Jan 2003
Posts: 74,992
U.S.S.A.
JohnRR
I Win
|
I Win
Joined: Jan 2003
Posts: 74,992
U.S.S.A.
|
Quote:
No I have'nt had them milled yet. On this chart for 71 it shows them at 79.5cc already www.cowtownmopars.com. Casting # is 3462346.
The link does not work .
Have the heads CC'd while they are there , my guess is they are more like 90 cc, 79.5 cc sounds like the NHRA min spec and NONE of the open chamber heads were that small out of the factory .
|
|
|
Re: Help me with 383 upgrade!
[Re: ireland383]
#210664
02/25/09 10:24 AM
02/25/09 10:24 AM
|
Joined: Jan 2003
Posts: 74,992
U.S.S.A.
JohnRR
I Win
|
I Win
Joined: Jan 2003
Posts: 74,992
U.S.S.A.
|
Quote:
Yes I will have them CCd. Try this one sorry. www.cowtownmopars.com/castingnumbers.html
I see they have the 906 listed at 79.5 cc also .... WRONG , that's the NHRA min spec , I have yet to see a 906 below 90cc that hasn't been cut . measure the casting at the outside row of bolts under the exh manifold mounting surface , they are typically 1.000 , if it's less that will give you an IDEA how much the head has been cut , if at all .
|
|
|
Re: Help me with 383 upgrade!
[Re: JohnRR]
#210665
02/25/09 12:52 PM
02/25/09 12:52 PM
|
Joined: Aug 2007
Posts: 6,095
Valencia, España
NachoRT74
master
|
master
Joined: Aug 2007
Posts: 6,095
Valencia, España
|
452s are CC listed ON SOME WEBSITES like 84 but they are OVER 90 ( I measured and I think got something like 92 )... SO THAT MADE make a mistake if we can say choosing my camshaft... now will need to mill down more than expected
With a Charger born in Chrysler assembly plant in Valencia, Venezuela
|
|
|
Re: Help me with 383 upgrade!
[Re: ireland383]
#210668
02/25/09 01:19 PM
02/25/09 01:19 PM
|
Joined: Aug 2007
Posts: 6,095
Valencia, España
NachoRT74
master
|
master
Joined: Aug 2007
Posts: 6,095
Valencia, España
|
IMHO the limit to mill down is:
-adjustable or not valvetrain or custom pushrods. You have rocker shims available though.
-clearence between pistons and valves
-iron or aluminium heads thinking on max compression an iron head can take without pinging or predetonation
-gasket planing to use
I'm planing myself mill down about one milimeter ( around 050 ) and mount 030 rocker shims...the 020 difference will be taken by hidraulic lifters, being preload won't be a BIG problem with the new ( although used, but low mileage ) Hughes valve springs I got at Carlisle. They are more compression valves than the HiPo stock ones even new.
That's just the plan that will be defined once pistons are down in the hole and measure the TDC with block deck. ( KB240s ). Block was decked already once.
Planing to use metallic headgasket
my cam will be MP 289/474 ( but I have a resto HiPo MP cam waiting just in case )
Porting on the way too. Mill down the intake faces too of course on an Eddy 2186 intake to match with new engine geometry
With a Charger born in Chrysler assembly plant in Valencia, Venezuela
|
|
|
Re: Help me with 383 upgrade!
[Re: NachoRT74]
#210669
02/25/09 01:21 PM
02/25/09 01:21 PM
|
Joined: Jan 2003
Posts: 74,992
U.S.S.A.
JohnRR
I Win
|
I Win
Joined: Jan 2003
Posts: 74,992
U.S.S.A.
|
Quote:
IMHO the limit to mill down is:
-adjustable or not valvetrain or custom pushrods. You have rocker shims available though.
-clearence between pistons and valves
-iron or aluminium heads thinking on max compression an iron head can take without pinging or predetonation
-gasket planing to use
I'm planing myself mill down about one milimeter ( around 050 ) and mount 030 rocker shims...the 020 difference will be taken by hidraulic lifters, being preload won't be a BIG problem with the new ( although used, but low mileage ) Hughes valve springs I got at Carlisle. They are more compression valves than the HiPo stock ones even new.
That's just the plan that will be defined once pistons are down in the hole and measure the TDC with block deck.
Planing to use metallic headgasket
my cam will be MP 289/474 ( but I have a resto HiPo MP cam waiting just in case )
Porting on the way too
Rocker shims are NOT the CORRECT way to make up for AGGRESSIVE head milling .
|
|
|
Re: Help me with 383 upgrade!
[Re: JohnRR]
#210670
02/25/09 01:23 PM
02/25/09 01:23 PM
|
Joined: Aug 2007
Posts: 6,095
Valencia, España
NachoRT74
master
|
master
Joined: Aug 2007
Posts: 6,095
Valencia, España
|
well, thats just a though, and if is a go, will be temporally for a while I get the money for adjustable valve train or custom pushrods... money will talks. Is a street car.
With a Charger born in Chrysler assembly plant in Valencia, Venezuela
|
|
|
Re: Help me with 383 upgrade!
[Re: NachoRT74]
#210671
02/25/09 01:28 PM
02/25/09 01:28 PM
|
Joined: Jan 2003
Posts: 74,992
U.S.S.A.
JohnRR
I Win
|
I Win
Joined: Jan 2003
Posts: 74,992
U.S.S.A.
|
Quote:
well, thats just a though, and if is a go, will be temporally for a while I get the money for adjustable valve train or custom pushrods... money will talks. Is a street car.
You don't need an adjustable valvetrain , thats an even bigger piss poor fix . Rocker shims are for CORRECTING INCORRECT rocker geometry, if you want to potentially SCREW UP YOUR rocker geometry thats the way to do it .
All you need is the CORRECT length pushrods if you are running a HYD. cam .
|
|
|
|
|
