|08-29-2012 09:42 PM|
|rock_dog||Thanks so much cdminter59! thats the kind of lay out i was looking for!|
|08-26-2012 03:10 PM|
newbie here building a 327 looking for atleast 400 hp.....HELP!!!!
Rock_Dog, Start out with a 327 block bored .030, decked to 9.005. Your crank cleaned and polished. 5.7 rods reconditioned or new I-Beam rods, flat top pistons IC792 are forged, KB100 are Hypereutectic. Your compression ratio with 64cc chamber heads IC792 is 9.8, with KB100 is 9.6. Choose one of these cams 12-676-4, XS268S, 1600-6000, .488/.501 lift and 230/236 duration @ .050 110 LSA or 12-220-5, 270S-8, 2000-6000.495/.495, 235/242 duration @ .050, 110 LSA. Edelbrock Performer RPM intake and a Holley or Demon 750 DP. HP should be from 425 @ 6000 rpm w/XS268S, 433 @ 6500 rpm w/270S-8. Torque 420 @ 4500 w/XS268S, 414 @ 4500 w/270S-8. With the block being decked use a Fel Pro .039-.041 head gasket to net 44-46 Quench. See toddalin's build sheet for how to finish setup.
|08-26-2012 02:34 PM|
Initially I tried 2 jets leaner on the primaries, but that created a lean surge while cruising. I returned the primary jets and it cleared right up, so took 1 jet size from the secondaries. Taking it from the secondaries also "squares up" the mixture better as it enters the manifold.
Also, this clearly illustrates that the "bog" is created by an over-rich condition (note that the A/F drops to ~10:1 at the point of bog), rather than a lean spot as most infer. The PO of the carb was trying to chase the bog and, based on conventional wisdom, put in the 28 squirter in the secondaries. The 25 in the primaries is standard. When I changed to the 21s the bog went away, though I've not done another dyno run to see where the A/F now is at this point. But the SOP, says much improved. Note how smooth the A/F ratio is past this point.
I recognize that the dyno is NOT THE STREET and most jet a bit richer for the street to account for unknown variables and load factors that come into play. But, my A/F ratio is still safe, and a slightly leaner mixture also typically improves gas mileage and throttle response.
|08-26-2012 01:44 PM|
toddalin said,,,and a dynojet dyno usually reads lower than a mustang chasis dyno. 12.8-12.9 af is great for the street.It would make more power with open exhaust and a little richer. so lets say your engine is 400 ish hp. for sure a good guideline to build 400 hp. My favourite carb for small v-8s like 327s is a 4777 with 4781 base plate and a few tweek
s like replaceable air bleeds and minor contouring etc.
Its a great share offering your parts list and actual dyno figures.
|08-26-2012 12:02 PM|
The dyno pull was before the addition of the Millerspeed underdrive system and Car Craft found 10 hp with the Millerspeed a 5,500 RPM. Also we did a bit more intake porting and carb tuning (at 12.8-12.9 A/F, it was a bit rich on the dyno), and I went 1 jet leaner on the secondaries. The RWHP, should now be a bit over 300.
Yes, he will need a solid lifter or maybe hydraulic roller cam to get there.
I was also able to get rid of the bog spots (~2,200-2,500) by reducing the squirters from 25F/28R to 21F/21R. Because I run a TKO600, these bog spots were just above my 5th-gear cruise RPM (~2,200) and getting rid of them was a real blessing when you get on it in 5th on the freeway.
BTW, I would be suprised if a stock 650 dp outflows this modified 600. But without modification, the 650 is probably a good choice.
|08-26-2012 10:51 AM|
|vinniekq2||read the first line of his build sheet.|
|08-26-2012 10:35 AM|
I didnt see what pistons you used?
|08-26-2012 10:29 AM|
|vinniekq2||copy toddalins build,upgrade carb to 650dp and add 10 degrees of duration to cam and 35 to 50 thou more lift.The duration will give you 700 more rpms which would give you another 30 hp and similar torque.I would say,use a solid lifter cam.|
|08-26-2012 10:10 AM|
What type of cam do yall think, Ive read on the 327 its better to stay around a 218-224 cam instead of going big, They said it makes it a high reving engine and makes better hp than going big on the cam, any truth to this?
And on the pic i posted above, what kind of pistons are those considered?
|08-26-2012 09:58 AM|
toddalin that engine is making 400 engine hp.the chasis dyno measures rwhp after accessories and driveline take up their share and exhaust too.
rock_dog a 327 does not really make big torque numbers,rev the little engine a bit higher and use a little more rear gear for the torque multiplier in the lower gears.A stock bottom end of a 327 can rev 6500 rpm and last with a good balance.I prefer a solid lifter cam especially for 327s
|08-25-2012 09:56 PM|
|rock_dog||Thanks for the info guys! I really appreciate it.|
|08-25-2012 09:51 PM|
Here's my combination and dyno sheet so you can see what it's going to take, cause I ain't there and this is a very healthy and streetable engine.
331 CI, pump-friendly 9.5:1 CR
K&N 14"x4" air filter, Corvette drop base and lid
Holley 600 dp, choke horn milled and blended, Primary - 69, Secondary – 74, Squirters - 21
1/2" Aluminum open spacer port matched to manifold, exterior polished
Edelbrock Performer RPM, port matched, exterior polished with all extraneous castings and lettering removed
Homemade lifter valley splash shield to keep hot oil off manifold bottom
Camel hump 1.94/1.50 heads hogged out to 2.02/1.60, pocket ported, port matched, pump-friendly hardened seats, 3-angle valve job
Cylinder bores clearanced to unshroud the valves
Comp Cams 1.52:1 roller-tip rockers
Crane Cam Vintage Muscle 327/350 hp cam, 222 degrees @ 0.05, 0.447" lift (with 1.50 rockers)
Doug Thorley headers, dechromed and ceramic-coated
2.5" mandral-bent exhaust (including tips), 2" cross-over just before rear axle
DynoMax stainless Ultra Flow mufflers
Millerspeed 1-1/2” Gilmer under drive belt drive system
Mallory Hyfire IV CD ignition box triggered off Accel points
Mallory high voltage chrome coil
Mallory spiral-wound coil wire
Mallory solid copper plug wires, ends soldered to wires
37 degrees total ignition advance
Carter high volume fuel pump
Melling high volume oil pump
Polished aluminum high flow water pump
Flex fan with polished aluminum spacer
Polished aluminum one-wire 100 amp alternator
Header Power Bracket
Keisler TKO600 5-Speed
225/60/15 Firestone Firehawk SZ50s on 7”-wide Western 30-spoke Turbine Wheels
|08-25-2012 09:38 PM|
another newbie question
What kind of pistons are these considered?
|08-25-2012 09:29 PM|
I would rather have the torque off the line i really think, I know I dont have the funds for both. lol.
What would you perfer in a drag car?
|08-25-2012 09:24 PM|
|s10mikey||400 hp built good crank, rods piston,s flat top,s,, forged still h beam rod,s for added strenght but your have a good start if you have a steal crank and good heads,, you just half to know wheather you want top end power or bottom end torque,,|
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