Re: 408 SB compression limits with iron heads...
[Re: stumpy]
#1131443
12/11/11 12:44 AM
12/11/11 12:44 AM
|
Joined: Jul 2003
Posts: 6,167
Maryland
GO_Fish
master
|
master
Joined: Jul 2003
Posts: 6,167
Maryland
|
Got Quench?? (there's an echo in here!)
Scott B.
"I'm a self-made man... I started with nothing, and I still have most of it!"
68 360 rusty B'cuda 'vert (GO Fish)13.59@ 98.72 mph
69 340 GTS stock 14.18@ 95.60 mph
01 5.9L Ram 1500 Quad Cab 4x4
01 3.5L 300M 16.23@ 86.97 mph
|
|
|
Re: 408 SB compression limits with iron heads...
[Re: stumpy]
#1131444
12/11/11 12:56 AM
12/11/11 12:56 AM
|
Joined: May 2004
Posts: 12,404
Taxes & Virus's R-US, NY
Dragula
I Live Here
|
I Live Here
Joined: May 2004
Posts: 12,404
Taxes & Virus's R-US, NY
|
Quote:
I'm running 10.2:1 on pump gas with my 408. Drives just fine.
I am also at 10.2:1 on my W2 motor and I will let you know when racing season opens.. Last year it was 13.1:1 and it would run fine on pump. Ran out of race fuel one day and had to get it loaded into the trailer and back out again and then into the shop, and it was fine on 93..Which I was worried about, but there is another person on here running 13:1 on pump and races it on race fuel. Kissmyaspen is his name I think, and his is also a W2 motor....He streets his, maybe he will chime in.
|
|
|
Re: 408 SB compression limits with iron heads...
[Re: Dragula]
#1131445
12/11/11 01:54 AM
12/11/11 01:54 AM
|
Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
|
Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
|
Quote:
Quote:
I'm running 10.2:1 on pump gas with my 408. Drives just fine.
I am also at 10.2:1 on my W2 motor and I will let you know when racing season opens.. Last year it was 13.1:1 and it would run fine on pump. Ran out of race fuel one day and had to get it loaded into the trailer and back out again and then into the shop, and it was fine on 93..Which I was worried about, but there is another person on here running 13:1 on pump and races it on race fuel. Kissmyaspen is his name I think, and his is also a W2 motor....He streets his, maybe he will chime in.
The static number doesnt mean a whole lot, thats just
a math number... like he showed on his previous engine
his cranking compression was 185... I would try to
keep it under 190 to be safe... I went with 10.9 on
my W-5 416 engine but that has a dynamic compression
of 9.2... when the intake cloes and the size of the
cam have a MAJOR part in the final out come
|
|
|
Re: 408 SB compression limits with iron heads...
[Re: ademon]
#1131447
12/11/11 03:26 AM
12/11/11 03:26 AM
|
Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
|
Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
|
Quote:
i'm running 205 psi on 93 pump
Thats pretty damn high for pump gas.... are you SURE
your gauge is correct(not doubting you but just asking)
as a rule everyone says stay under 200 but I like
a cushing
|
|
|
Re: 408 SB compression limits with iron heads...
[Re: ademon]
#1131448
12/11/11 03:28 AM
12/11/11 03:28 AM
|
Joined: Feb 2005
Posts: 5,221
Branson, Mo.
joedust451
OP
super gas
|
OP
super gas
Joined: Feb 2005
Posts: 5,221
Branson, Mo.
|
Cool, that gives me hope then, I shouldn't have more then 160-165, The cam will be mild, Its Lunati's new cam line, The price is great, 99.00 with lifters, Here are the specs.
Lunati "Bare Bones"
Adv. Dur. 280/290
214/224 @50
.443/.465
112 LSA
Intake centerline 107
1500-5500
Now i'm sure some will say why such a small cam, I'm basically going for a street cruiser with 3.23/3.55 gears, 26-2800 stall, If i go with better heads down the road, i'll change cam & converter, I want it to be very street friendly & cruise on the interstate, This may not happy just yet, just wanting to know about compression limits with pump gas with a small cam & iron heads.
So with a cam like this, 9.6-9.7 should be ok?
Last edited by joedust451; 12/11/11 03:35 AM.
|
|
|
Re: 408 SB compression limits with iron heads...
[Re: joedust451]
#1131449
12/11/11 03:31 AM
12/11/11 03:31 AM
|
Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
|
Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
|
Quote:
Cool, that gives me hope then, I shouldn't have more then 160-165, The cam will be mild, Its Lunati's new cam line, The price is great, 99.00 with lifters, Here are the specs.
Lunati "Bare Bones"
Adv. Dur. 280/290
214/224 @50
.443/.465
112 LSA
1500-5500
7187PR Lifters
Now i'm sure some will say why such a small cam, I'm basically going for a street cruiser with 3.23/3.55 gears, 26-2800 stall, If i go with better heads down the road, i'll change cam & converter, I want it to be very street friendly & cruise on the interstate, This may not happy just yet, just wanting to know about compression limits with pump gas with a small cam & iron heads.
So with a cam like this, 9.6-9.7 should be ok?
With the wide LSA you will have lower cranking pressure
so yes you should be fine
|
|
|
Re: 408 SB compression limits with iron heads...
[Re: MR_P_BODY]
#1131450
12/11/11 04:33 AM
12/11/11 04:33 AM
|
Joined: Sep 2004
Posts: 6,906
IL, Aurora
ademon
master
|
master
Joined: Sep 2004
Posts: 6,906
IL, Aurora
|
Quote:
Quote:
i'm running 205 psi on 93 pump
Thats pretty damn high for pump gas.... are you SURE
your gauge is correct(not doubting you but just asking)
as a rule everyone says stay under 200 but I like
a cushing
ya, its a 360 with flat tops at zero, 039 gaskets, and j heads at 59cc, cam is a solid comp 520/540 lift 244/252 @.050, 110, whats keepin it alive is its in a demon with a 4,400 stall, fresh air intake, very cold plugs/with a msd, and 30 total on the street. i love running them at the raged edge!! great throttle response and a nice POP out the tips!!
Last edited by ademon; 12/11/11 04:35 AM.
|
|
|
Re: 408 SB compression limits with iron heads...
[Re: Dragula]
#1131451
12/11/11 11:05 AM
12/11/11 11:05 AM
|
Joined: Aug 2004
Posts: 1,413
Newark,Ohio
kissmyaspen
pro stock
|
pro stock
Joined: Aug 2004
Posts: 1,413
Newark,Ohio
|
Quote:
Quote:
I'm running 10.2:1 on pump gas with my 408. Drives just fine.
I am also at 10.2:1 on my W2 motor and I will let you know when racing season opens.. Last year it was 13.1:1 and it would run fine on pump. Ran out of race fuel one day and had to get it loaded into the trailer and back out again and then into the shop, and it was fine on 93..Which I was worried about, but there is another person on here running 13:1 on pump and races it on race fuel. Kissmyaspen is his name I think, and his is also a W2 motor....He streets his, maybe he will chime in.
Not me... I have a 360 with the kb 190 pistons with X heads... Earlier I had a valve break.. Not the head pop off.. Was running pump gas at the time.. Not 100% sure it was the gas or just parts failure... But I now run race gas... I dont think the pump gas we have now is close to what it was 5 years ago.. 
79 Dodge Aspen
12.265 at 109.75 MPH
67 Satellite NSS/E
11.83 @ 110
1968 Plymouth Road Runner 472 Hemi
3 time MOPAR NATIONALS CHAMP '03 FWD and '06 & '09 Street.
'07, '10, '12 Mopar Nats runner-up Street.
|
|
|
Re: 408 SB compression limits with iron heads...
[Re: ademon]
#1131452
12/11/11 02:42 PM
12/11/11 02:42 PM
|
Joined: Jan 2005
Posts: 12,419
Kalispell Mt.
HotRodDave
I Live Here
|
I Live Here
Joined: Jan 2005
Posts: 12,419
Kalispell Mt.
|
Quote:
Quote:
Quote:
i'm running 205 psi on 93 pump
Thats pretty damn high for pump gas.... are you SURE
your gauge is correct(not doubting you but just asking)
as a rule everyone says stay under 200 but I like
a cushing
ya, its a 360 with flat tops at zero, 039 gaskets, and j heads at 59cc, cam is a solid comp 520/540 lift 244/252 @.050, 110, whats keepin it alive is its in a demon with a 4,400 stall, fresh air intake, very cold plugs/with a msd, and 30 total on the street. i love running them at the raged edge!! great throttle response and a nice POP out the tips!!
You would probably make more power with less compression and more timing. I have never seen a J head happy with less than 35 degrees timing. I bet a magnum head would really wake up your combo, they are generally happiest with 30 degrees advance not to mention a more effiecent burn and a little more flow.
I like a lot of cylinder preasure, heck, if a Geo Metro can pump 210 psi and run better on 87 than 93 than we should be able to also.
I am not causing global warming, I am just trying to hold off a impending Ice Age!
|
|
|
Re: 408 SB compression limits with iron heads...
[Re: HotRodDave]
#1131453
12/11/11 10:32 PM
12/11/11 10:32 PM
|
Joined: Feb 2005
Posts: 5,221
Branson, Mo.
joedust451
OP
super gas
|
OP
super gas
Joined: Feb 2005
Posts: 5,221
Branson, Mo.
|
Quote:
Quote:
Quote:
Quote:
i'm running 205 psi on 93 pump
Thats pretty damn high for pump gas.... are you SURE
your gauge is correct(not doubting you but just asking)
as a rule everyone says stay under 200 but I like
a cushing
ya, its a 360 with flat tops at zero, 039 gaskets, and j heads at 59cc, cam is a solid comp 520/540 lift 244/252 @.050, 110, whats keepin it alive is its in a demon with a 4,400 stall, fresh air intake, very cold plugs/with a msd, and 30 total on the street. i love running them at the raged edge!! great throttle response and a nice POP out the tips!!
You would probably make more power with less compression and more timing. I have never seen a J head happy with less than 35 degrees timing. I bet a magnum head would really wake up your combo, they are generally happiest with 30 degrees advance not to mention a more effiecent burn and a little more flow.
I like a lot of cylinder preasure, heck, if a Geo Metro can pump 210 psi and run better on 87 than 93 than we should be able to also.
have to agree with you there Dave, My stock dished piston 360 magnum with RHS heads ran best at 30* total, ran on junk 87, I had a Geo Metro, I can't believe they pumped out that much cylinder pressure  . It was a peppy little car & the gas mileage was super.
|
|
|
|
|
