View Full Version : What can my 370 hold?


HydroStream6
11-30-2006, 10:12 PM
Well in the neverending quest for more power, I'm starting to think of what I'll need to upgrade in the offseason on my engine. I have a iron block 370 (stock stroke, 4.03" bore) with the following:

Diamond 11515 pistons (-15cc), ProSelect rings
Scat 4340 H beam forged rods
Stock LS1 crank
LS6 cam
241 heads with stock sized valves... cleaned up a little, nothing special
GM MLS 6L gaskets
ARP head bolts

I know ARP studs are definitly a good idea at this point. I'm not postive where my CR is at this point... Diamonds site lists 9.4:1 with 66cc heads, I'm not positive how the cam affects that. Anyways. as built, how much power, assuming optimal tuning, good gas, etc, can this engine hold? I'm right around 600rwhp right now and I have nitrous that I've yet to spray also.

Thanks
Adam

SSilverSSurfer
11-30-2006, 10:17 PM
more than the 600hp you have now plus nitrous

Mr_president
11-30-2006, 10:24 PM
1200 or so at the motor my guess....900 to the tires

vanillagorilla
12-01-2006, 01:22 PM
TTT, I'm fixing to build a motor similar to this and I'd like to know too.

Drewstein
12-02-2006, 03:33 PM
1200 or so at the motor my guess....900 to the tires
/agree

1320
12-02-2006, 03:46 PM
if you balance it just right ............and extra large pep and saus pizza and two liter. lol

I couldnt resist. now back on topic.

NA$TY-TA
12-02-2006, 04:51 PM
Plenty...... with a good tune..... id lower the comp some with some 72cc chmabered heads...... Some worked 6.0L's would work well and drop you to where i am... about 8.87:1

Kyle

BIG BAD BLACKSS
12-02-2006, 08:31 PM
I have pretty much that same combo, my shortblock came from speed inc, 6.0 iron block, -14.9cc diamond pistons, with diamond pro-select rings, but i have eagle 4340 rods with the L-19 bolts added, and a stock crank, studded bottomend, im planning on running a 72CC truck head with the GM MLS gaskets and im looking at 9.2 or 9.3:1 compression. This is the same shortblock speed inc takes into the 8s and puts down 995RWHP with. Except i added the upgraded L-19 bolts, they said they run the bolts that normally come with the eagle h beams in their motor and not L-19s like i upgraded to. Otherwise im identical to their shortblock.

NA$TY-TA
12-02-2006, 09:06 PM
I have pretty much that same combo, my shortblock came from speed inc, 6.0 iron block, -14.9cc diamond pistons, with diamond pro-select rings, but i have eagle 4340 rods with the L-19 bolts added, and a stock crank, studded bottomend, im planning on running a 72CC truck head with the GM MLS gaskets and im looking at 9.2 or 9.3:1 compression. This is the same shortblock speed inc takes into the 8s and puts down 995RWHP with. Except i added the upgraded L-19 bolts, they said they run the bolts that normally come with the eagle h beams in their motor and not L-19s like i upgraded to. Otherwise im identical to their shortblock.



See thats what i have and who ever did your math for u for your compression is missing something........ 4.03" Bore, 3.622" stroke, -15cc dish piston 72cc chamber head, .054 head gasket crush thickness.....
I get 8.7:1 out of most online calculators.....

BIG BAD BLACKSS
12-02-2006, 10:22 PM
This was posted by tom from speed inc.

"Those are the correct pistons for your target compression ratio.

Enter Cylinder Bore Size 4.030
Enter Piston Stroke Length 3.622
Enter Head Gasket Bore Diameter 4.030
Enter Compressed Head Gasket Thickness .058
Enter Combustion Chamber Volume In CCs 72
Enter Piston Dome Volume In CCs Negative For Dished Pistons (Use '-') -15
Enter Piston Deck Clearance Negative If ABOVE Deck (Use '-') : 0

Calculated Engine Compression Ratio 9.194284170932075
Total Displacement Volume 92.39288038220492

Go to http://www.csgnetwork.com/compcalc.html if you want to verify for yourself.

This is the exact combo we use in ALL of our 370" Boost motors, including our 995 RWHP shop car turbo combo. WE run this exact spec short block, with AFR 72cc 225's, and the GM 6.0 MLS head gaskets."

POST #11
http://www.ls1tech.com/forums/showthread.php?t=590175

EDIT: Just plugged in the #s myself and im coming up with 8.637878924666251! :cry: Im gonna go nuts before i get this all together and running!

NA$TY-TA
12-03-2006, 08:40 AM
This was posted by tom from speed inc.

"Those are the correct pistons for your target compression ratio.

Enter Cylinder Bore Size 4.030
Enter Piston Stroke Length 3.622
Enter Head Gasket Bore Diameter 4.030
Enter Compressed Head Gasket Thickness .058
Enter Combustion Chamber Volume In CCs 72
Enter Piston Dome Volume In CCs Negative For Dished Pistons (Use '-') -15
Enter Piston Deck Clearance Negative If ABOVE Deck (Use '-') : 0

Calculated Engine Compression Ratio 9.194284170932075
Total Displacement Volume 92.39288038220492

Go to http://www.csgnetwork.com/compcalc.html if you want to verify for yourself.

This is the exact combo we use in ALL of our 370" Boost motors, including our 995 RWHP shop car turbo combo. WE run this exact spec short block, with AFR 72cc 225's, and the GM 6.0 MLS head gaskets."

POST #11
http://www.ls1tech.com/forums/showthread.php?t=590175

EDIT: Just plugged in the #s myself and im coming up with 8.637878924666251! :cry: Im gonna go nuts before i get this all together and running!



See thats what i was saying......

wether your told its ,054 or ,058 for crush thickness and 0 deck were still really close to the same and closer to 8.6-8.7-1 then 9:1
Im happy with that .. i wanted under 9:1

Kyle

ChicagoTransAm
12-03-2006, 03:50 PM
How did they get these #s then? Something is wrong, he insisted that this was the right piston for me, adn told me to go check, of course i didnt go check cause he sounded so confident and posted the #s. Im gonna have to talk to them on monday.

Oops this is BBBSS i accidently posted o my buddies name. Ill update this with what i find out.

HydroStream6
12-04-2006, 06:16 PM
Good to know.. thanks guys!

My father has a 02 6.0L in his Silverado... I should swap heads with him, it'd be beneficial for both of us!

BIG BAD BLACKSS
12-07-2006, 10:53 PM
Can anyone confirm if this motor will be 8.7 or 9.2 compression with a 72cc head. I cant get a straight answer i keep hearing different stuff. Speed inc tells me just under 9.2, then tells me to check the math if i want and tells me what to fill in, i put those #s into the site they recommend and i get around 8.7 I sent them a PM and i get the "we use this combo for every boost motor, you can return it for a full refund if you want" again. While i appreciate them willing to still refund me after this amount of time, i still believe in their product and still want to run it. I just need to know what size head to get. :( :bang:

NA$TY-TA
12-07-2006, 11:06 PM
Over and over ive had the same combo i have now and its under 9:1

BIG BAD BLACKSS
12-07-2006, 11:48 PM
Ive been doing some research and using the #s speed provided and their calculator heres a chart of what compression id be at with what size chamber.

Then i have a list of heads and what size chambers they are offered in, anyone have any other heads im missing? Im assuming i can get the heads milled a littlke or have the chambers enlarged some for not too much $?? Just seeing what realistic options i have for a 9.1-9.3 compression ratio. Ive thought about running some nitrous through it so i was thinking a little more compression would be better? I keep hearing 9.0-9.5 is the sweet spot for centrifigal blowers.

62cc = 9.504
63cc= 9.409
64cc= 9.317
65cc= 9.227
66cc= 9.138
67cc= 9.053
68cc= 8.967


AFR 62cc/72cc
PATRIOT 72cc LS6 ported
STOCK LS1 67cc
EDELBROCK 65CC
PATRIOT LS6 64cc
TRICKFLOW 64cc
STOCK LS6 63cc
RHS 62cc
DART 62cc

I was hoping to use a 72cc AFR head since i had the shortblock built, looking for 9.0+ compression, but i dont see that happeneing without having to deck then a descent amount.

FANTAZ28
12-08-2006, 09:27 AM
ls1's are never at zero deck... usualy out of the hole a little...... but im not 100 percent on that.

Pro Stock John
12-08-2006, 09:51 AM
I know ARP studs are definitly a good idea at this point. I'm not postive where my CR is at this point... Diamonds site lists 9.4:1 with 66cc heads, I'm not positive how the cam affects that. Anyways. as built, how much power, assuming optimal tuning, good gas, etc, can this engine hold? I'm right around 600rwhp right now and I have nitrous that I've yet to spray also.

Thanks
Adam
-Assuming 104 octane, 700-800rwhp depending on your compression.
-If you can access 70-72cc heads I'd swap over, reduces your octane requirements.

I've made 867rwhp thru an unlocked A3 with C16, not sure what I'd make on 104 unleaded.

NA$TY-TA
12-09-2006, 10:08 AM
Yeah why are you so set on above 9:1??? Most that make BIG power want lower then 9:1 because they can make MORE power with less octain, without detination.


Kyle

BIG BAD BLACKSS
12-11-2006, 06:16 PM
Yeah why are you so set on above 9:1??? Most that make BIG power want lower then 9:1 because they can make MORE power with less octain, without detination.


Kyle

I keep hearing that blowers like 9-9.5:1 And turbos are more in the 8.0-9.0 range? Have i been misled? I also want to hit it with a 100 or more shot on top of the boost, and i know nitrous likes compression. I wanted to make good power on 93 and use race fuel when spraying. Im open to new suggestions for compression.

HUNTER02SS
12-11-2006, 07:39 PM
I have a 370 and hoping to make 800rwhp with a F-1C/R. :drive: