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What's the most power you've been able to achieve?

260Alpine

Silver Level Sponsor
Kelly, I would just go up a couple jet sizes and go to a smaller number power valve. Richen the whole carb.
 

V6 JOSE

Donation Time
Hi Matt,

Your V6 isn't weak. It will take 6,000 rpm shifts all day long without even breathing hard. The factory red line for the l;ittle 2.8 V6 is 6,000, which means it is safe at 6,000 rpm. The engine itself will take more than that, but the anciliaries, like the water pump, alternator etc. don't like it very much. I would not worry about it, since you say you don't want to race it. The 2.8 V6 doesn't start to make power until about 2,500 - 3,000 rpm. The V6 is the happiest running at at least 3,000. your V6 will outlast most other engines.


QUOTE=DaisyPusher;176433]What is you personal top speed with a 2.8l? I'd like to know the limits of the engine but I'd prefer to not surpass them and find out the hard way...

Cheers, Matt[/QUOTE]
 

260Alpine

Silver Level Sponsor
A little bit milder cam. Everything Optimized. I punched in IN 220 @ .050, EX 210 @ .050. IN .460 lift, EX .470. Inbetween stock and Jose grind. 17" vacuum at idle of 800RPM. 15 initial and 32 total @ 3000RPM ignition timing. Mild head porting and 2.9 valves. 8.5 to 1 Compression. Offy intake, 390 Holley, Headers. Cam @ 5 advance(1 tooth). Advertised duration probably around 270 intake, 260 exhaust. Still showing lean under 2000RPM. Trying to install a scanner to show chart. 195 FTLBS TQ @ 4500RPM, 190 Flywheel HP @ 6000RPM. That would be approximately 152 @ rear wheels. Remember this is a computer program and hypothetical.
 
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RootesRacer

Donation Time
A little bit milder cam. Everything Optimized. I punched in IN 220 @ .050, EX 210 @ .050. IN .460 lift, EX .470. Inbetween stock and Jose grind. 17" vacuum at idle of 800RPM. 15 initial and 32 total @ 3000RPM ignition timing. Mild head porting and 2.9 valves. Offy intake, 390 Holley, Headers. Cam @ 5 advance(1 tooth). Advertised duration probably around 270 intake 260 exhaust. Still showing lean under 2000RPM. Trying to install a scanner to show chart. 195 FTLBS TQ @ 4500RPM, 190 Flywheel HP @ 6000RPM. That would be approximately 152 @ rear wheels. Remember this is a computer program and hypothetical.

Performance trends cam analyzer?
 

260Alpine

Silver Level Sponsor
Performance Trends Engine Pro. I'm having issues installing the scanner to show the graph. I'll figure it out.
 

260Alpine

Silver Level Sponsor
Yeah, Most of the computer Dyno programs are pretty optimistic. I try to use conservative inputs. Real engine Dynos usually subtract 15% for HP at the wheels. I subtract 20%. Say, this combo is 175HP on a real Dyno. Subtract 15% and you get 149 at the wheels. So my guestimate of 152HP is probably pretty close.
 

MikeH

Diamond Level Sponsor
Guys, Here is what the program shows: Cam straight up 8 to 1=5.5, 9 to 1=6, 10 to 1=6.9, 11 to 1=7.5. 4 degrees cam advance 8 to 1=5.8, 9 to 1= 6.5, 10 to 1=7.2, 11 to 1=7.9. 8 degrees cam advance 8 to 1=6, 9 to 1=6.8, 10 to 1=7.5, 11 to 1=8.2. This tells me ideally you should have 10 to 11 to 1 for straight up. 9.5 to 10.5 to 1 for 4 degrees advance. 8 degrees advance 9 to 10 to 1. all graphs in the 7 range show 190 to 200HP. I'll do a chart with a lower duration cam next.

So with my build plans; 2.9 crank,2.9 valves, .030 over bore, 0 deck height, and rough calculations show 9.3:1 CR, offy intake, Holley 390, it looks like I would need to run one tooth advanced on the cam.
 

260Alpine

Silver Level Sponsor
Mike, Does the 2.9 crank put the piston at zero deck without decking the block? The longer stroke will change the Dynamic number. The calculations were done with a 2.8 crank stroke. Are you sure you only have 9.3 compression? I'll run the 2.9 stroke to see the difference.
 

MikeH

Diamond Level Sponsor
Mike, Does the 2.9 crank put the piston at zero deck without decking the block? The longer stroke will change the Dynamic number. The calculations were done with a 2.8 crank stroke. Are you sure you only have 9.3 compression? I'll run the 2.9 stroke to see the difference.

This is planned without decking the block. I want to just square it up. I found that the '74 pistons have a different pin placement that gets it close to 0 with the 2.9 crank. Rods are the same.
 

260Alpine

Silver Level Sponsor
Mike, I like to zero deck when possible also. My question is, if .090 down is stock and 8.5 to 1. I think you would be at least 10 to 1 at zero deck. Which would be fine with the Jose grind cam. I'll run simulations with 9.3 and 10.
 

260Alpine

Silver Level Sponsor
Mike, Even with 5 degrees advance at 9.3 to 1 the Dynamic compression is only 6.8. At 10 to 1 it is perfect at 7.3.
 

RootesRacer

Donation Time
So with my build plans; 2.9 crank,2.9 valves, .030 over bore, 0 deck height, and rough calculations show 9.3:1 CR, offy intake, Holley 390, it looks like I would need to run one tooth advanced on the cam.

You sure 1 tooth is gonna be 8 degrees?

Remember that cam degrees double the crank degrees (which is what the engine simulator uses).

You want 4 degrees at the cam to make 8 at the crank. You may be able to get there with an offset key. Otherwise you may need to make a timing adjustable cam drive or a custom cam gear.
 

260Alpine

Silver Level Sponsor
Yes, I see what you are saying, in crank degrees. Most chain setups have 4 degrees keyways on the crank sprocket so would only move the cam 2 degrees. 10 crank degrees is a bit much and changes every thing. You would have to check piston to valve clearance for that much and the Dynamic numbers and cam specs would be way different. I would suggest an offset key or another keyway in the cam or crank gear at 4 crank degrees advanced. Thanks, RootesRacer for opening my eyes. Seems nothing is easy.
 
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todd reid

Gold Level Sponsor
What's the most power you'vr been able to acheive?

Jim,

I am following this discussion with interest - very educational. So the take away from the previous exchange with RootesRacer is that previous references to advancing/retarding a cam by 4 cam degrees should really be 2 cam degrees (and 4 crank degrees)?

Is there any point to crunching the numbers on a basically stock engine, or in your experience have the factory engineers already got it right?

Thanks in advance!

TR
 

260Alpine

Silver Level Sponsor
Todd, Yes, Cut another keyway in cam or crank gear or use offset key. The picture with 3 keyways on cam gear earlier in this thread. I could run the numbers for a stock cam if I knew the specs like in the Jose cam. Mustang II or Ranger? Or both. The factory engines use tame specs , compromise for emissions and economy. That last mild cam simulation is a good midrange cam.
 
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