ok guys after all my hard work and machine shop trips i have completed the 454 motor. the only problem is with my compression ratio. the motor was built around me using alum heads. well i ran out of money (house and bills and wife) and had to use my 049 casting oval port heads. this puts the motor right at 11:1 with the cast iron heads and this is what came up after pouring the cylinders and heads to exact figures (i love how picky some engine builders are) i am using a crane power max cam. what kind of gas will i have to run in this to make it happy? i want to use pump gas with some octane booster but not race gas (i have a 23 gallon tank) i have a points style distrubitor with the unilite conversion and blaster 2 coil. is the 11:1 too much for a weekend driver that will go on highway trips? also i want to find out my DCR.

1. will it run on pump gas with octane booster?
2. what brand octane booster should i run?
3. how much timming should i limit it to total with the vaccum advance hooked up?
4. What will my dcr be?
5. what does it mean he installed the cam at 108.5?

thanks in advance

motor specs:

454 2 bolt bored .060 over for 468 ci
zero deck
trw forged pistons yeilding 11:1 compression
steel crank radius cut
factory rods shot peened and arp wave lock bolts
arp main studs
049 oval port heads factory valves and no port work
edelbrock performer intake
holley 750 vaccum sec carb 3310-3
hooker supercomp 2" primaries with 3 1/2 collectors
2000 boss hog converter

crane powermax hydraulic
crane cam grind number: h-286-2 (replaces cch-286-2)

lift at cam intake 314 exaust 325
lift at valve intake 534 exaust 553

cam timming at .0042:

intake opens at 34
intake closes at 72 duration 286
exaust opens 83
exaust closes 33 duration 296

Cam timming at .050:

intake opens 6
intake closes 40 duration 226
exaust opens 55
exaust closes 1 duration 236

max lift for intake at 107 atc
max lift for exaust at 117 atc

then he added that it was installed at 108.5

I am ready to fire up the beast this weekend and am kind of nervous and excited. comming back from a cam falure is a little tense feeling.

also does anyone have a hp/tq estimate for this combo??

What is the dome height of your pistons and what is the head cc's?

I would run 36* total timing by no more than 3000 rpms..with like a 12-16* base

119 cc chamber head. the dome i am not sure of but the builder poured it and came up with 11.01 compression ratio. he slightly milled the piston to get it to that. the block is at 0 deck and has a felpro blue head gasket. will it run on 93 octane pump gas? what is my dynamic compression ratio?

I'm making some assumptions to get to the DCR. If assuming the 11.0 is dead correct. Your DCR comes out to about 8.3 or 8.4. You should be OK if you watch your timing and run 93 octane. Make sure the engine has adequate cooling and see what happens. Worst case, you go to a slightly bigger CAM - not a huge expense and your DCR comes down closer to 8. You are definitely safe there.

What gear are you running? You would be better off with 3.73's or at least 3.55's to let the motor spin up without lugging it. A little higher stall would help too but since you are limited on funds (aren't we all?), I think you can make do.

Good luck,

Troy.

yea the compression ratio is dead on at 11.01:1. he spent 2 days on ccing and pouring to make 100% sure of compression ratio. it has 2.73 gears in it now and i will be putting 3.55 in it as soon as i can afford it.

i will be putting 2 bottles of octane booster in it just to be safe. it has a 23 gallon tank.

I wouldn't worry about the octane booster unless you get some ping. It doesn't do very much to raise the Octane. It should be a crime to advertise the way they do. Try it with pump gas first and go from there. Retard your timing a little if you must. 2.73's could be a problem. Give it a try and see. It may be OK until you can change the gears.

Troy.

Cornbread,
The Crane H286 Powermax you intend to run is going to push your cylinder pressure way too high. I would bet somewhere around 200 - 210 cranking. By comparison, I am putting a 408 BBC back together. This motor had the correct 402 +.030 forgings along with the correct '70 290 heads, block deck was virgin but the cylinder heads had been cut. Cranking compression was 185 - 190 (stone cold engine) with an older style Crane HIT-280, [280 / 290,224/234@.050, .525/.550 on 114 LSA] and poor ring seal. The cam you are looking into only has 2 more degrees @.050 but on 112 LSA and a little bit more seat duration. By comparison, my motor now has been decked and reassembled with the same .030 pistons (just needed honing and fresh rings). From the info I have, my compression should be 10.3 . I am looking into a little more duration cam for my application. Was considering solids but am leaning to the new Comp LS6 hydraulic (229/236 @.050 on 112 LSA) or something similiar. At 185-190 cold cranking, my engine had to run with limited timing and was actually somewhat of a slug because of it. I would think in a 11 to 1 454 you would want to use a cam with at least a 236/246 @ .050 (assuming hydraulic) which is the next Crane listing. Not to mention, the Crane 286 will run out of breath in a high compression 454 in a hurry. Just my .02.

FYI, Installed @ 108.5 = 3.5 Deg Advance.

CornBread, I ran my 461 at about 11.3/1 with iron heads, and I could run 93 octane with no pinging at all, no sign of detonation on plugs either. I agree that the 2:73's might be a little trouble, but other than that, it shouldnt be a problem...watch the timing and check your plugs...stay away from the octane boost.

I think you'll have an issue. Any mall airports nearby? Get a 4 gal can filled with 100 low lead and run it with 93-94 for a bit and 'sneak up" on pump gas only. Thats whats I did. 8.6:1 DCR with old alum "heat dissipator" heads. You'll want to throw more gear at it as soon as the budget allows.

427L88,
I have read some of your input, you have similiar ideas as to the BBC Combo. I personally like the 3.76 stroke in a BBC. Good usable torque and comes on like h--- at 4000 & up. I have ran several 454 motors over the years and was never satisifed with them in a "true" street car. The bottum end was either too high for street tires or the engine was just way too chocked with a "street" exhaust system. IMO, the combo Cornbread has could be a killer with the following changes:
Engine : at least 10 - 15 degrees more valve timing. Much better flowing intake - RPM, Stealth, Excelerator or Similiar, 3 inch exhaust at least back to the mufflers.
Suspension : Mods are required (relocate control arms, pinnion angle, air-bag (assumed this was a Chevelle).
After much trial and experimentation, I have been able to calibrate my application of DD2000 to a number of published engine combinations. I have this engine as follows:
RPM X 1000 HP TQ
2.0 181 475
2.5 236 496
3.0 286 501
3.5 338 506
4.0 382 501
4.5 410 479
5.0 409 429
5.5 381 364
6.0 335 293
6.5 276 223