Any guesses on 340 HP w this combo?

-
swinger340

swinger340

Well-Known Member
Joined
Jul 25, 2010
Messages
2,273
Reaction score
62
Location
Maine
10.5:1 .030 over 340. Forged crank, lightened 340 rods w/ ARP bolts, TRW 2316 forged pistons. Balanced (heavy) assembly. Solid flat tappit cam .525/.535 lift 240/248 duration @ .050 Comp 1.5 roller rockers on top of edelbrock ootb closed chambered heads. Performer rpm intake w/ a holley 750 DP. Will be dynoing in a few weeks. Nice having a buddy w a machine shop. He offered to dyno it for free on some weekend, so why not. Im hoping for close to 400 hp. Just a cruiser.
 
im going to say you thinking close and maybe a little under rating it you may jave more, i have a 340 30 over about 10 to 1 , 540-549 lift flat tappet with 1,6, fully ported eddys, victor intake, 750 aed, so fairly close comparison, on a rear wheel dyno it made 384 at the wheels, so at the motor figureinga 15 percent loss in power through the automatic maybe 450 at flywheel just guessing so i thunk you will be pleased keep us posted, and good luck i went to champion race plugs in mine and gained a few hp if i remember i will look the number up and post it, they worked great and was recomended for the heads:D
 
I plugged all your info into an engine HP calculator I found on a Honda Civic racing site & it came out to a little over 6500 HP.
 
I have 340 , 40 over solid flat tappet cam, TRW pistons and approx 9.25 compression so I can run premium unleaded - I like to drive it! T/A heads with stock rockers a little more lift and a little less duration, minor porting where I took the bumps out of the intake ports. I got 396 hp at the flywheel at 6200 RPM, 392 at 6300, 390 at 6400 which seemed to be enough as I think I was at the top of my valve train capability. Assuming you use real gas with your compression ratio I think you will be pleased, my guess would be 425 to 450 maybe a bit more.
 
Fired the girl up this morning. after a little tuning and some jet changes, ending up w 74 P/86 S. She ran a max of 428HP @ 6200 and a max torque of 406 @ 5500. With 35 degrees total timing. On 100 octane. Very pleased w the results, more than i was expecting is always a good thing. Hoping it will run fine on 91 is the next thing. She has 185 lbs of cranking pressure, and a DCR of 8.9:1. Should be a fun little motor in the 69 4 speed swinger. Not a stroker, but good enough for now.
 
pettybludart said:
Those are some good #,s,hope you can get it to run on the 91 without bing.Good luck.:D
Click to expand...
If detonation occurs with 91 ill just have to swap the cam to an XE282S lowering my DCR to 8.3:1, drop cranking pressure, change my TQ. and HP as well. Damb!!!! Im hoping that is not the case. We got it tunedpretty well and it will idle @ 750 RPM. Im hoping it will be OK or mabe an octane booster added to bump the octane up a little will be all I need
 
If it does detonate, pull some ignition timing out of it.
 
i just gotta know^^^^^^^^^^^^^^^^^^ does that cat actually think he is friggin superman???????????rofl.lol
 
swinger340 said:
10.5:1 .030 over 340. Forged crank, lightened 340 rods w/ ARP bolts, TRW 2316 forged pistons. Balanced (heavy) assembly. Solid flat tappit cam .525/.535 lift 240/248 duration @ .050 Comp 1.5 roller rockers on top of edelbrock ootb closed chambered heads. Performer rpm intake w/ a holley 750 DP. Will be dynoing in a few weeks. Nice having a buddy w a machine shop. He offered to dyno it for free on some weekend, so why not. Im hoping for close to 400 hp. Just a cruiser.
Click to expand...

with the aluminum heads you should have no problem running 91 octane gas..

I ran a 10.7 to 1 360 with eddy aluminum heads on 89 octane, cam was a 230/237 duration at .050. with 35 degrees of timing..
 
swinger340 said:
Im hoping it will be OK or mabe an octane booster added to bump the octane up a little will be all I need
Click to expand...

I was always told that octane booster was pretty much a joke, that it required absurd amounts to make a noticeable difference.

want to raise the octane a bit? pick up some avi-gas at the local airport and mix it in your tank with pump gas.

I priced some avi-gas last month, and it's only a bit more than pump gas in price, but a hellish amount cheaper than the price you'll pay at a track/strip. That advice came from one of my friends who runs an a-body at the drag strip, he told me to get the fuel at the airport, because the price to buy it at the strip means you're getting bent over...with no lube. disgust
 
74Dusted said:
I was always told that octane booster was pretty much a joke, that it required absurd amounts to make a noticeable difference.

want to raise the octane a bit? pick up some avi-gas at the local airport and mix it in your tank with pump gas.

I priced some avi-gas last month, and it's only a bit more than pump gas in price, but a hellish amount cheaper than the price you'll pay at a track/strip. That advice came from one of my friends who runs an a-body at the drag strip, he told me to get the fuel at the airport, because the price to buy it at the strip means you're getting bent over...with no lube. disgust
Click to expand...
There is a small gas station near me and the guy owns a private air port along w 25 muscle cars so @ his fuel station one of the tanks is full of 100 octane avi-gas. That is where I purchased it for the dyno run. 5.00 a gallon.
 
Well that works out pretty well then. It's a little cheaper here for the 100LL, but I live out in the middle of BFE, so that means a 30+ minute drive 1 way to the airport to pick up some fuel to put in my car.

It's not really that far, just lots of old winding roads, with tons of redlights (every time you pass through a town) and low speed limits. Not to mention road construction that will be going on for the next 2 years.

Supposedly it's going to take them another 2 years to replace this one bridge on that route (small bridge, 2-lane, about 25' long), they've already been "working" on it for a year... of course when I say working, I mean they've got traffic cones up and traffic is routed around the bridge (in a 2-lane fashion that's so narrow that if 2 fullsize trucks were to pass each other, they'd knock their mirrors off) and all you ever see is the workers standing around doing nothing.
 
You must log in or register to reply here.
-

Back
Top