Help me with a new motor combo

[69 N.O.X. RATT]

It never ends :crazy: I am tearing the motor down in anticipation of the new rear end (Tom's 12 bolt spool 3.5" half shaft, etc. Should be good for 1000 hp) and tranny (Liberty built Richmond 5 spd. Should also be good for 1000 hp) Goals: Make 875-1000 hp with nitrous. No blowers or turbos. High compression is ok (up to 13.5 to 1), but cam timming streetable enough to get 5000 miles on a set of lifters. Current cam 255 / 262 at ,050 on a 112 .652 lift. Leaning towards staying with current cam, open to ideas. Current thoughts: I need to get some track time so I am going to stay with a 460-496 cu in. Heads, Thinking AFR 315 CNC, suggestions ? Possible tunnel ram, how big carbs ? (460-496 cu in.) I am getting a new forged crank, probably Eagle, maybe Lunati I have L-88 rods, either going to replace them with Eagles, may have a good line on Lunati. May put bushings in the L-88's and do some grinding on them to make them live. Any problem with worked L-88 rods with good bolts up to 1000 hp and 7000 rpms +? Intake, Keep the Victor Jr. ? Get a tunnel ram (which one and which carbs) Dart intake ? I am pretty confident in my abality to put a combination together, but there are guys here with way more knowledge than me. I am looking for some ideas or maybe some past experiance. Current combo: 454 +.030 HP 1000 solid roller 252 262 at .050 on a 112, .652 lift. Ported Edelbrock ovals 318 cfm at .652 10.8 JE Victor Jr, slight work done to it 3450 ish lbs car 125 mph on motor, best mph ET goals of 9. something

[TeenagerWith74Vette]

All you would need is about 750hp to run in the 9s with your car. That should be no problem with a big-block.

My motor only made 578hp on a flywheel dyno and I put a very safe 150 shot on top of that. My car will run 9.60s as soon as I can get it down the track completely.

I just went to the dyno 2 weeks ago with my engine builder to dyno a high compression 540 with small Merlin heads. The motor made 917hp at 7200rpm.

If I were you I would set your current goals witha pump gas motor. One example is another 548 my engine builder built last fall. It made 748 hp with 10.0 to 1 compression. That motor was built for a 300 shot of nitrous. That motor would likely put your car into the 8s.


As far as heads I would definately go with the Edelbrock race heads. They are the absolutely best 23* heads on the market. These heads must be ported, however, in order to work well.

Jay

[81vette]

I ran the following specs through DD2003: 468 CI, AFR 315, 2 - 700 cfm carbs on a Tunnel-Ram, Large Tube headers through mufflers, solid roller 255/262 @.050 .651/.651 on a 114 with 11:1 CR.

RPM HP TQ
3000 268 469
3500 327 490
4000 406 533
4500 500 584
5000 598 628
5500 673 642
6000 733 642
6500 771 623
7000 811 608
7500 850 595
8000 820 538

A high flow single plane with 1000cfm carb was down about 70 HP.

Mark


[Modified by 81vette, 6:33 PM 11/9/2003]

[TeenagerWith74Vette]

Desk top Dyno is fun to play with sometimes, but those figures are way out in left field.

You need to get yourself a professional engine builder that can put your combo together to match your car and goals.

Jay

[69 N.O.X. RATT]

Thnaks for the help so far.

I am pretty confident with my ideas and ability to turn a wrench, don't need a professional engine builder. Besides there are guys on the forum I would rather let work on my motor than a lot of the "Pro's"

[81vette]

Desk top Dyno is fun to play with sometimes, but those figures are way out in left field.
Jay

What do you mean....those figures are a direct result of my expert engine building practices. All you need to do is design an engine, such as the one above, with 115 vol. eff. and you too can make 1.82 HP/CI. :lol: :lol: :lol:

Mark



[Modified by 81vette, 7:14 PM 11/9/2003]

[norvalwilhelm]

John you know more then I do about combinations but your cam is not that wild. 1 ran a Crane with 256, 264 @ .050 for years on the street. I don't like the victor Junior intake, have one sitting in the closet down stairs and it never outperformed my heavily reworked LS6 high rise.
As for bushing the rods I had a business years ago doing rods for alot of the race guys and we ran a 1/8th oil hole in the top and another in the front of the rod drilled from underneath on a angle up. Never had a pin seize ever. I have a cupboard with blown parts and pistons with broken rods but not one pin seized.
A 496 is a good combination for a 454 and even a mild one with oval heads and mild cam can put out 600 horse using stock type 454 pistons with the domes milled down .100. If you are buying a crank anyway it is the same price. It temps me at times to go that route too.
Most guys don't tear an engine down in antisipation of a new rearend? :lol: :lol:

[norvalwilhelm]

You need to get yourself a professional engine builder that can put your combo together to match your car and goals

Jay I feel the same way as John does about putting a motor together. The professional might know a combination but when it comes to actually assemblying a motor I feel I can match just about anyone. Like John we are maticulous in checking everything and making it right.
I leave nothing NOTHING to chance. Everything is checked , made right before assembly. My motors go together 3 or 4 times before the final time .
John can do it , he just needs ideas on combinations.
I don't know that much about combinations, I have had a few really good combinations before going the blower route but no one puts and engine together for me. No one.
Sometimes when working on an engine gut feeling tells you something isn't right and most times you work until you find what your gut was telling you. Just last week I was sound asleep and at 2 in the morning my eyes suddenly poped open and I found what my gut was telling me. I knew the mistake in my sleep.
I have every faith in John's ability to do it himself.

[69 N.O.X. RATT]

Thanks Norval.

I am leaning towrds a tunnel rammed 12.5 to 13.5 to 1, 468 to 496 with AFR 315 CNC heads. Leaving the cam I have alone.