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Re: Big Block head gaskets to lower compression....? [Re: Dodgem] #936849 02/25/11 01:38 PM 02/25/11 01:38 PM
Joined: Feb 2005 Posts: 4,311 Prospect, PA BSB67 master
BSB67 master Joined: Feb 2005 Posts: 4,311 Prospect, PA	190 psi with CA 91 octane might not be doable. My experience is it won't work with gas in PA. Last edited by BSB67; 02/25/11 01:58 PM.

Re: Big Block head gaskets to lower compression....? [Re: BSB67] #936850 02/25/11 01:42 PM 02/25/11 01:42 PM
Joined: Jan 2003 Posts: 74,979 U.S.S.A. JohnRR I Win
JohnRR I Win Joined: Jan 2003 Posts: 74,979 U.S.S.A.	Enginemasters 470 ran 12.2 compression with .035 quench , alum heads , and reverse flow cooling on 91 oct with no detonation at 36* , I do not know what the cranking compression was .

Re: Big Block head gaskets to lower compression....? [Re: Dodgem] #936851 02/25/11 01:47 PM 02/25/11 01:47 PM
Joined: Jan 2004 Posts: 27,347 Today? Who Knows? 1_WILD_RT Management Trainee
1_WILD_RT Management Trainee Joined: Jan 2004 Posts: 27,347 Today? Who Knows?	Quote: Oil consumption is huge in detonation problems. I can't see you actual cranking number being more than 190 lb and with aluminum heads you should be fine. I believe quench is less critical with aluminum heads than iron heads. Quench should allow the same power at less spark lead than a less than perfect quench motor but I am sure people over rate it mostly on their magazine learnen not 100% the best sources. While I agree oil can/will cause detonation your inference that quench is over rated & magazine "learnen" to me suggests you haven't built any motors with effective quench... I've played with hotrods for 30+ years & early on I foolishly trusted my machine shops to spec & build my motors.. They never ran like I thought they should.. Now I do everything but the machine work & I measure the work very accurately... I hold a tight quench which has often required more trips to the machine shop because most local shops even "performance" shops seem to be conservative or just plain sloppy... If you trust the numbers your given & don't measure it yourself you really don't know what you've got.. The O/P's .017 in the hole is exactly what my pistons spec at.. But they measured between .023 & .029 because the decks weren't at blueprint spec & they weren't square.... If his .017 number is a measured number than he's on the borderline of quench/no quench.. But if his pistons are actually over .020 in the hole he has no quench effect at all... I'd rather see the number under .040... "The Armies of our ancestors were lucky, in that they were not trailed by a second army of pencil pushers."

Re: Big Block head gaskets to lower compression....? [Re: 1_WILD_RT] #936852 02/25/11 01:49 PM 02/25/11 01:49 PM
Joined: Oct 2003 Posts: 3,698 NE Oklahoma V Von master
Von master V Joined: Oct 2003 Posts: 3,698 NE Oklahoma	Quote: Quote: \ While I agree oil can/will cause detonation your inference that quench is over rated & magazine "learnen" to me suggests you haven't built any motors with effective quench... \ Well some fellows at Ross pistons dont see that quench is all that important... 72 RR, Pump gas 440, 452s, 3800 lbs, Corked, ET Radials,. 11.33@117.72. Same car, bone stock 346s, 9.5 comp, baby solid. 12.24@110.

Re: Big Block head gaskets to lower compression....? [Re: Von] #936853 02/25/11 01:53 PM 02/25/11 01:53 PM
Joined: Jan 2004 Posts: 27,347 Today? Who Knows? 1_WILD_RT Management Trainee
1_WILD_RT Management Trainee Joined: Jan 2004 Posts: 27,347 Today? Who Knows?	Quote: Quote: Quote: \ While I agree oil can/will cause detonation your inference that quench is over rated & magazine "learnen" to me suggests you haven't built any motors with effective quench... \ Well some fellows at Ross pistons dont see that quench is all that important... When your building a race engine that doesn't need to run on pump swill then you don't have to worry about quench... You want to drive with crap fuel you might want to try it... "The Armies of our ancestors were lucky, in that they were not trailed by a second army of pencil pushers."

Re: Big Block head gaskets to lower compression....? [Re: JohnRR] #936854 02/25/11 02:01 PM 02/25/11 02:01 PM
Joined: Feb 2005 Posts: 4,311 Prospect, PA BSB67 master
BSB67 master Joined: Feb 2005 Posts: 4,311 Prospect, PA	Quote: Enginemasters 470 ran 12.2 compression with .035 quench , alum heads , and reverse flow cooling on 91 oct with no detonation at 36* , I do not know what the cranking compression was . Sure. Reverse cooling and big cam....no surprise at all

Re: Big Block head gaskets to lower compression....? [Re: 1_WILD_RT] #936855 02/25/11 07:42 PM 02/25/11 07:42 PM
Joined: Oct 2003 Posts: 3,698 NE Oklahoma V Von master
Von master V Joined: Oct 2003 Posts: 3,698 NE Oklahoma	quote When your building a race engine that doesn't need to run on pump swill then you don't have to worry about quench... You want to drive with crap fuel you might want to try it... My discussion with the guys at Ross was a 10.5 to 1 470 that Im building. Will run on pump fuel... I think the quench factor is WAY overrated..and the guys at Ross backed me up. Ive personally have had 2 instances with no quench and 10.5 to comp with iron heads and no detonation problems. Building another non quench motor with 10 to 1 in iron and the 470 mentioned. Also putting together a 11 to 1 512 with aluminum heads. All on pump gas. I dont expect any problems with any of them. IMO, the cam plays more of a role than quench... If you look around there are plenty of guys on here "breaking the rules" so to speak. Last edited by Von; 02/25/11 07:44 PM. 72 RR, Pump gas 440, 452s, 3800 lbs, Corked, ET Radials,. 11.33@117.72. Same car, bone stock 346s, 9.5 comp, baby solid. 12.24@110.

Re: Big Block head gaskets to lower compression....? [Re: Von] #936856 02/25/11 11:48 PM 02/25/11 11:48 PM
Joined: Feb 2010 Posts: 18,493 Granite Bay CA Kern Dog OP Striving for excellence
Kern Dog OP Striving for excellence Joined: Feb 2010 Posts: 18,493 Granite Bay CA	My cranking compression was between 180 and 192 the last 2 times that I checked. These consistant numbers made diagnosing the oil burning problem difficult. My machinist thinks that the 2 cams that went bad may have led to rapid ring wear. I also wonder if the overrich Demon 850 may have caused some increased wear due to dilution of the oil and cylinder wash. A Dyno shop had installed a 7.5 power valve. I have read recently that the power valve should be HALF the number of the engines vacuum while idling in gear. This motor certainly never had 15 inches of idle vacuum. The overrich condition during cruise and throttle tip in must have dumped alot of fuel in the cylinders! I switched to a 3.5 PV at the same time that I added vacuum advance, but by then, the motor was in need of a rering anyway. I am now leaning toward using the .039 gaskets I already have. The tighter sealing pistons and (hopefully) reduction of oil burning should return the motor to the power level it had when I first built it in October 2004. Thanks everyone for all the suggestions!

Re: Big Block head gaskets to lower compression....? [Re: Kern Dog] #936857 02/26/11 02:14 AM 02/26/11 02:14 AM
Joined: May 2008 Posts: 5,399 Aurora, Colorado 451Mopar master
451Mopar master Joined: May 2008 Posts: 5,399 Aurora, Colorado	Back to the original question, The Fel-Pro #1105 is the 0.051" thick, 4.590" bore, 13.7cc performance head gasket. At $74 each I think the Cometic gaskets are a better deal. For Reference: The #1009 is 0.039" thick, 4.410" bore, 9.9cc The Info is from the Felpro gasket catalog: http://ecatalog.federalmogul.com/digiPub21/Felpro_Performance_and_Sport_Gasket_Catalog/index.htm The standard ROL#HG31130 is 0.045" thick, 4.505" Bore, 11.8 cc, and cost about $12 each, The ROL Performance/High Temp #HG31130HT is the same size and costs about $22 each from this place I found: http://www.prostockautoparts.com/products/1965-DODGE-CUSTOM-V8--383-Head+Gasket,+Individual.htm I don't know what the 440 source 0.051" thick head gasket is? Mr gasket offers the thinner gaskets, thicker copper gaskets, and MLS gaskets, but still in the 0.043" thickness. I found these that may be what your looking for: SCE Pro Copper Head Gaskets, 0.062" and various bore sizes are $125 pair from Summit. or Flatout Gaskets #900464520 are 0.064" thick, 4.520 diameter, 16.8cc (calculated from bore & thickness), and cost $140/pair from Summit. Here is a link to summit chrysler big block head gaskets. You can do "show all" on gasket thicknesses. It looks like the SCE gasket have the largest selection of thicker head gaskets? http://www.summitracing.com/search/Make/...40/?Ns=Rank\|Asc

Re: Big Block head gaskets to lower compression....? [Re: Kern Dog] #936858 02/26/11 09:42 AM 02/26/11 09:42 AM
Joined: Jan 2003 Posts: 74,979 U.S.S.A. JohnRR I Win
JohnRR I Win Joined: Jan 2003 Posts: 74,979 U.S.S.A.	Quote: My cranking compression was between 180 and 192 the last 2 times that I checked. These consistant numbers made diagnosing the oil burning problem difficult. My machinist thinks that the 2 cams that went bad may have led to rapid ring wear. He THINKS, that caused the rapid ring wear ??? You lost 2 cams in that motor so you threw in a 3rd to see if it would be ok ? What do your piston skirts look like ? Last edited by JohnRR; 02/26/11 09:57 AM.

Re: Big Block head gaskets to lower compression....? [Re: JohnRR] #936859 02/26/11 02:30 PM 02/26/11 02:30 PM
Joined: Oct 2003 Posts: 3,698 NE Oklahoma V Von master
Von master V Joined: Oct 2003 Posts: 3,698 NE Oklahoma	[quoteHe THINKS, that caused the rapid ring wear ??? You lost 2 cams in that motor so you threw in a 3rd to see if it would be ok ? What do your piston skirts look like ? X2 72 RR, Pump gas 440, 452s, 3800 lbs, Corked, ET Radials,. 11.33@117.72. Same car, bone stock 346s, 9.5 comp, baby solid. 12.24@110.

Re: Big Block head gaskets to lower compression....? [Re: Von] #936860 02/26/11 03:40 PM 02/26/11 03:40 PM
Joined: Feb 2010 Posts: 18,493 Granite Bay CA Kern Dog OP Striving for excellence
Kern Dog OP Striving for excellence Joined: Feb 2010 Posts: 18,493 Granite Bay CA	The skirts were scuffed and lightly scratched, but they cleaned up nicely by glass bead blasting and green scotch brite pads. The cylinders honed out nicely. I dont foresee oil consumption being a problem now. As stated, he found that the oil rings had lost all their tension, so oil was slipping by them, then past the worn compression rings. I dont understand the reference to putting in the 3rd cam.... The compression #s looked consistant. If testing showed unusually low #s on even one hole I would have dug deeper. I have replaced dead cams in motors before and didnt remember any problems. The '509 cam looks great still. I credit that to the use of Valvoline VR1 oil AND the Comp Cams additive. I started using the higher grade oil AFTER the 2 cams went bad and I did some research on the subject. I have built several motors in my time, but this is the first one geared toward real performance. Its also the first one with valvesprings STIFFER than stock. The first cam went bad in 2006. If this car were driven daily I'm sure that the problems would have cropped up sooner, but I drive it maybe 1000 miles per year.

Re: Big Block head gaskets to lower compression....? [Re: challengermike] #936861 03/02/11 05:22 AM 03/02/11 05:22 AM
Joined: Feb 2010 Posts: 18,493 Granite Bay CA Kern Dog OP Striving for excellence
Kern Dog OP Striving for excellence Joined: Feb 2010 Posts: 18,493 Granite Bay CA	Quote: cant you just back the timing down for the street and mix in alittle racegas at the track and bump it back up? I have been doing this very thing. It just sucks to be limited this way. I figured that a slight drop in squeeze would make the car more fun to drive. I've put very few miles on this car since 2004.

Re: Big Block head gaskets to lower compression....? [Re: JohnRR] #936862 03/02/11 06:22 AM 03/02/11 06:22 AM
Joined: Dec 2005 Posts: 4,231 State of retirement 5 52savoy master
52savoy master 5 Joined: Dec 2005 Posts: 4,231 State of retirement	How about removing all this fuss and go to E85 fuel? Seems like the thing to do instead $witching everything around and then praying for it to work. http://www.e85refueling.com/states.php?PHPSESSID=22be46d9cc75f6a306af40299ebfa161

Re: Big Block head gaskets to lower compression....? [Re: 52savoy] #936863 03/08/11 04:11 AM 03/08/11 04:11 AM
Joined: Feb 2010 Posts: 18,493 Granite Bay CA Kern Dog OP Striving for excellence
Kern Dog OP Striving for excellence Joined: Feb 2010 Posts: 18,493 Granite Bay CA	I decided to go ahead with the Fel Pro 1009 gaskets that are common to the standard Full gasket set. The motor is back in the car and the TTI headers are in. I like to clean or repaint stuff before I install them, so sometimes my projects run a little longer than they would on a beater car. I'm reusing the '509 cam since the lobes were good and I kept the lifters in order. I looked back at some notes that I kept from when I FIRST built the motor in 2004. It ran like a raped ape and sounded great. I should have it running tomorrow.

Re: Big Block head gaskets to lower compression....? [Re: Kern Dog] #936864 03/08/11 05:05 AM 03/08/11 05:05 AM
Joined: Jul 2008 Posts: 30,424 Florida STAYcation dOrk ! The village idiot's idiot
dOrk ! The village idiot's idiot Joined: Jul 2008 Posts: 30,424 Florida STAYcation	ONE more time ...water injection THEN you can put MORE timing in it ...and if you mix some alky in the tank .. it will make MORE power.

Re: Big Block head gaskets to lower compression....? [Re: dOrk !] #936865 03/08/11 06:21 AM 03/08/11 06:21 AM
Joined: Feb 2010 Posts: 18,493 Granite Bay CA Kern Dog OP Striving for excellence
Kern Dog OP Striving for excellence Joined: Feb 2010 Posts: 18,493 Granite Bay CA	I remember seeing these kits on the shelves of Super Shops back in the day. How and where is the water injected? If its a "plate under the carb" system like some nitrous kits, I'm out. The distance between the air cleaner and the hood can be measured with a feeler guage. If it requires drilling a hole in the intake like a vacuum port, I'm listening........

Re: Big Block head gaskets to lower compression....? [Re: Kern Dog] #936866 03/08/11 08:40 AM 03/08/11 08:40 AM
Joined: Jan 2003 Posts: 74,979 U.S.S.A. JohnRR I Win
JohnRR I Win Joined: Jan 2003 Posts: 74,979 U.S.S.A.	Quote: I decided to go ahead with the Fel Pro 1009 gaskets that are common to the standard Full gasket set. That is not the gasket that comes in the standard full kit , it is a 8519

Re: Big Block head gaskets to lower compression....? [Re: Kern Dog] #936867 03/08/11 02:34 PM 03/08/11 02:34 PM
Joined: Jul 2008 Posts: 30,424 Florida STAYcation dOrk ! The village idiot's idiot
dOrk ! The village idiot's idiot Joined: Jul 2008 Posts: 30,424 Florida STAYcation	Quote: I remember seeing these kits on the shelves of Super Shops back in the day. How and where is the water injected? If its a "plate under the carb" system like some nitrous kits, I'm out. The distance between the air cleaner and the hood can be measured with a feeler guage. If it requires drilling a hole in the intake like a vacuum port, I'm listening........ The only thing that is needed is a small line and nozzle directed into the primary side of the carb normally through the top of the air cleaner. SpearCo is the system I used(and I still have a couple of sets left!) ... but Edelbrock made one too. The GOOD systems meter the liquid THREE diff ways .... engine vaccum, engine RPM and the nozzle size. I have not done any type of tweaking lately(not in years) ... but I did back in the day. I had a gasser-dually(400 motor) ... with a camper ...towing a 32 foot trailer ...and experimented with it then. It REALLY helped with power(OF COURSE not like NOS!), helped with MPG, allowed me to back-off to mid-grade fuel AND cleaned the motor up. It is just like steam-cleaning ... just as an experiment - I swapped out a severely carboned-up spark plug for a good one .... and in 75-100 miles .. it was like new .... I used to have a search on eBay for these systems ...and some of them went for cRaZy money. So some people still use them. I am going to use one on my motorhome project ...and am going to tune the whole combo with a wide-band O2. I do not know how WI will affect that.

Re: Big Block head gaskets to lower compression....? [Re: JohnRR] #936868 03/09/11 02:56 AM 03/09/11 02:56 AM
Joined: Feb 2010 Posts: 18,493 Granite Bay CA Kern Dog OP Striving for excellence
Kern Dog OP Striving for excellence Joined: Feb 2010 Posts: 18,493 Granite Bay CA	Quote: That is not the gasket that comes in the standard full kit , it is a 8519 Hmmm. What is the difference between the 2? The ones in the set are the blue perma torque. These are supposed to be .039 compressed. I was REALLY close to firing the motor today. The #5 and #7 spark plugs felt as if they were cross threading so I stopped. I need to buy a thread chaser to clean the threads. Heres the car that the motor will go into... 6519749-00000005.JPG (95 downloads)

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