Edelbrock heads and compression

flagg · 02-07-2001, 10:46 PM

Does anybody know what the compression is with stock 89 motor and Edelbrock 6037's?? I was reading an article and they were saying it was 9.5:1 does this sound right or a little high?

LX XLR8R · 02-08-2001, 12:17 AM

im running 9.7:1 with my dss block so stock is def lower than that..if i rember correctly stock is 8.9:1 with 54cc heads so the 60cc heads should be about 8.5:1..dont quote me though on that

------------------
1987 black notch(ex 4 banger)
DSS 306 w/ main support...Elderbrock 6028 heads..gt-40 intake..24# injectors...70 mm tb..77 pro-m...accel 300+..mac full legnth..tremec w/ pro5oh...full MAC exhaust,off road h-pipe,long tubes, catback...ron davis radiator..subframes, control arms...CFDF II..o yea holley FPR sucks..dont buy one..

Mach 1 · 02-08-2001, 05:34 AM

I have the edel 6037's, and im guessing my compression to be about the same as stock. The info above me is way off, stock is around 9:1 with the stock heads, which are like 60-64cc range. The 6037's have a 60cc chamber, so it is esentially the same as stock, maybe a little higher, but not much at all.

------------------
1993 GT/AOD
'93 Mustang GT

Green92LX · 02-08-2001, 09:37 AM

Don't quote me either, but when I bought my 6037's I read that the stock compression was around 9:1, and with the 60cc heads it would bring it up to around 9.5:1....I did read this somewhere...

------------------
1992 5.0 LX, Edelbrock 6037 Heads, Cobra Intake,E-303, 1.6 Roller Rockers,65MM Holley TB, 75 MM Pro M Mass Air, 190 LPH FP w/ 24 lb injectors,BBK equal length shorties,offroad h-pipe,Mac Flowpath Mufflers, Pro 5.0, 3.73's,Motorsport "C" springs,welded subframe connectors, Ponies w/ 225/50 Nittos, 93 Cobra Spoiler

Daily driver: 89 Coupe with 205K plus, BBK shorties,offroad h-pipe,2-chamber flowmasters with dumps, cut and welded stock shifter...and it runs like a champ.

flagg · 02-08-2001, 09:51 AM

The reason I ask guys is cuz I am running a ProCharger right now. When we have triple digit temps here in the summer I boost without any trace of detonation. I had my eye on some pistons that would make me aprox. 9.7:1, figuring that a couple more point won't do anything but give me a slight increase in power. I have been told I can run safely 10:1 because of the 3core intercooler. Also have adjustable FMU so I can dial in a bit more fuel on top if needed.
My thought are if running aprox, 9.5:1 right now safely no sense in going down in compression. Some opinions please thanks.

flagg · 02-08-2001, 09:11 PM

86GT · 02-09-2001, 12:10 PM

I was on the corral.net technical calculators and according to that, you'll have 9.3:1 with the 60cc heads on the stock short block. I'm running the Edelbrock 6032 heads on an 89 shortblock, so that's close to what my compression should be.

Mach 1 · 02-09-2001, 12:17 PM

If your boosting, i wouldnt chance raising compression. just dial in a few more pounds...

eatsgm · 02-09-2001, 01:02 PM

I have milled edelbrock perf RPM head.
I did the test on edel. head to know the
volume of the chamber. Amazingly it as
63-64 cc. (Maybe 60 cc is with bigger
valves 2.02.). It also bring compresion
from 8.9:1 to 9.05:1. I had to perform
a heavy milling to bring compression
to 10:1 (dont remember how much however)

hope this help

flagg · 02-09-2001, 08:48 PM

Thanks guys, I am actually running the 6032's but figured everyone would know about 6037 cuz it seem that more run them. I was reading an article last night. From what I read it is actually the effective compression that matters and supposedly 16:1 - 18:1 is supposed to be managable. With 9lbs and 9.7 I will still have under 16:1 so I think I am going to go for it. I will have good low end torque and when under boost I expect a monster =) thanks again
If it really is 63 or 64 I am even safer.

NO SLO PK · 02-10-2001, 11:14 AM

Actually, the 6037s cause less detonation compared to the stock heads, in my experience. With the 6037s, I could dial in another 2-3 degrees easily without detonation. I was also able to increase boost a little. The short explanation to this is the 6037s are made of aluminum vs. the stock heads which are of cast iron. It has to do with the different thermodynamic properties of the two materials.

------------------
'91 LX
Procharger, 3 row intercooler, extrude honed Cobra intake, Mac full Length Headers, 30# inj., 73mm C&L, 75mm tb, E303 cam, 289 rods, ported E7 heads, MSD, T-Rex w/255 lph Walbro, 5 lug conversion, Cobra R wheels, 3.27 gears and Moser Axles.

[This message has been edited by NO SLO PK (edited 02-10-2001).]

02-07-2001, 10:46 PM	#1
flagg Registered Member Join Date: Feb 2000 Location: AZ Posts: 75	Edelbrock heads and compression Does anybody know what the compression is with stock 89 motor and Edelbrock 6037's?? I was reading an article and they were saying it was 9.5:1 does this sound right or a little high?

02-08-2001, 09:11 PM	#6
flagg Registered Member Join Date: Feb 2000 Location: AZ Posts: 75	ttt

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02-08-2001, 12:17 AM	#2
LX XLR8R Dirk Diggler Join Date: Feb 1999 Location: SLOATSBURG, NY Posts: 1,931	im running 9.7:1 with my dss block so stock is def lower than that..if i rember correctly stock is 8.9:1 with 54cc heads so the 60cc heads should be about 8.5:1..dont quote me though on that ------------------ 1987 black notch(ex 4 banger) DSS 306 w/ main support...Elderbrock 6028 heads..gt-40 intake..24# injectors...70 mm tb..77 pro-m...accel 300+..mac full legnth..tremec w/ pro5oh...full MAC exhaust,off road h-pipe,long tubes, catback...ron davis radiator..subframes, control arms...CFDF II..o yea holley FPR sucks..dont buy one..

02-08-2001, 05:34 AM	#3
Mach 1 Registered Member Join Date: May 1999 Location: Georgia Posts: 3,866	I have the edel 6037's, and im guessing my compression to be about the same as stock. The info above me is way off, stock is around 9:1 with the stock heads, which are like 60-64cc range. The 6037's have a 60cc chamber, so it is esentially the same as stock, maybe a little higher, but not much at all. ------------------ 1993 GT/AOD '93 Mustang GT

02-08-2001, 09:37 AM	#4
Green92LX Registered Member Join Date: Jun 1999 Location: North Haven,CT Posts: 336	Don't quote me either, but when I bought my 6037's I read that the stock compression was around 9:1, and with the 60cc heads it would bring it up to around 9.5:1....I did read this somewhere... ------------------ 1992 5.0 LX, Edelbrock 6037 Heads, Cobra Intake,E-303, 1.6 Roller Rockers,65MM Holley TB, 75 MM Pro M Mass Air, 190 LPH FP w/ 24 lb injectors,BBK equal length shorties,offroad h-pipe,Mac Flowpath Mufflers, Pro 5.0, 3.73's,Motorsport "C" springs,welded subframe connectors, Ponies w/ 225/50 Nittos, 93 Cobra Spoiler Daily driver: 89 Coupe with 205K plus, BBK shorties,offroad h-pipe,2-chamber flowmasters with dumps, cut and welded stock shifter...and it runs like a champ.

02-08-2001, 09:51 AM	#5
flagg Registered Member Join Date: Feb 2000 Location: AZ Posts: 75	The reason I ask guys is cuz I am running a ProCharger right now. When we have triple digit temps here in the summer I boost without any trace of detonation. I had my eye on some pistons that would make me aprox. 9.7:1, figuring that a couple more point won't do anything but give me a slight increase in power. I have been told I can run safely 10:1 because of the 3core intercooler. Also have adjustable FMU so I can dial in a bit more fuel on top if needed. My thought are if running aprox, 9.5:1 right now safely no sense in going down in compression. Some opinions please thanks.

02-09-2001, 12:10 PM	#7
86GT Sniffed too much n20 Join Date: Oct 1998 Location: Ont, Canada Posts: 1,018	I was on the corral.net technical calculators and according to that, you'll have 9.3:1 with the 60cc heads on the stock short block. I'm running the Edelbrock 6032 heads on an 89 shortblock, so that's close to what my compression should be.

02-09-2001, 12:17 PM	#8
Mach 1 Registered Member Join Date: May 1999 Location: Georgia Posts: 3,866	If your boosting, i wouldnt chance raising compression. just dial in a few more pounds...

02-09-2001, 01:02 PM	#9
eatsgm Registered Member Join Date: Sep 1998 Location: Pont-Rouge,Quebec,Canada Posts: 55	I have milled edelbrock perf RPM head. I did the test on edel. head to know the volume of the chamber. Amazingly it as 63-64 cc. (Maybe 60 cc is with bigger valves 2.02.). It also bring compresion from 8.9:1 to 9.05:1. I had to perform a heavy milling to bring compression to 10:1 (dont remember how much however) hope this help

02-09-2001, 08:48 PM	#10
flagg Registered Member Join Date: Feb 2000 Location: AZ Posts: 75	Thanks guys, I am actually running the 6032's but figured everyone would know about 6037 cuz it seem that more run them. I was reading an article last night. From what I read it is actually the effective compression that matters and supposedly 16:1 - 18:1 is supposed to be managable. With 9lbs and 9.7 I will still have under 16:1 so I think I am going to go for it. I will have good low end torque and when under boost I expect a monster =) thanks again If it really is 63 or 64 I am even safer.

02-10-2001, 11:14 AM	#11
NO SLO PK Registered Member Join Date: Mar 1999 Location: Arcadia, CA, USA Posts: 731	Actually, the 6037s cause less detonation compared to the stock heads, in my experience. With the 6037s, I could dial in another 2-3 degrees easily without detonation. I was also able to increase boost a little. The short explanation to this is the 6037s are made of aluminum vs. the stock heads which are of cast iron. It has to do with the different thermodynamic properties of the two materials. ------------------ '91 LX Procharger, 3 row intercooler, extrude honed Cobra intake, Mac full Length Headers, 30# inj., 73mm C&L, 75mm tb, E303 cam, 289 rods, ported E7 heads, MSD, T-Rex w/255 lph Walbro, 5 lug conversion, Cobra R wheels, 3.27 gears and Moser Axles. [This message has been edited by NO SLO PK (edited 02-10-2001).]