WLingle92lx

I just build a new 347 and am currently breaking the motor in slowly.

I took the car out a couple days ago and got on it a little bit. I have a 5800 rpm pill in the ignition box. the
timing is also only set at 10 degrees base, runing on a 93/110 octane mix. The car seemed pretty quick and feels like it has a lot of potential.

This parts on this motor should let it rev to 7200+ rpm easy, so how much more power should it have ifI rev it to 7200-7500 rpms, run much more timing (like 15-16 degrees) run it on straight 110 VP race fuel and geta proper tune?

Thanx !

mattdel

if your planning on running straight 110 octane, all the time, you can run alot more timing than that.

as far as your power curve, only you will know that. you NEED to get a dyno tune.
its 100% impossible to tell you what your actual physical redline will be, regardless of the parts you have.

r.barn

First, dont be afraid to break motor in Hard.
you need to run engine hard to seat rings properly
It's just important to fully warm up the engine first. stay away from
low rpm heavy loads, ie too high a gear, and from freeway cruising.

Power depends on what heads you have, cam, compression ratio.
Need some more info there.

You need to go ahead and put more timing in there too. 10* base is VERY conservative.
I'm surprised you arent having idle and starting issues with so low of timng in there.

w8less

why kind of heads and compression do you have?

hyr or solid roller cam?

WLingle92lx

Compression ratio is 12.0 to 1
Heads are AFR185cc heads (gasket matched) w/AFM Hi-Rev Springs
Cam is a Lunati 51018 hydro roller with 252 duration @0.050 & 620 lift (3200-7000rpm range)
Intake is a Trickflow Box

FullAuto

Normally, I'd say if you built your combo to shift at 7200, then you should feel quite a bit of difference when you're shifting now at ~5600 or so. But with a 12.0:1 347 spinning that high, it'll probably start laying over a little short with those smaller heads. I hope you're not using stock lifters too.

r.barn

FullAuto, is right it takes some special vale train parts to maintain high rpm
power band over 6,500 rpm, and yeah AFR 205's would feed it better at upper rpms.

at 12-1 and 347 with AFR 185's I bet you're somewhere around 400rwhp
tune will be needed for sure to maximize top of the power band.
With race gas and lots of timing over 400rwhp would not surprise me if
all the right parts are there.

Think I remember Anderson doing a High Rev 347 in one of their cars
and it was making like 450+rwhp at 7,000+rpm, with similar parts.

WLingle92lx

so how much of a difference in power would there be going from 10 degrees to like 15+

The heads were flowed at 28* water psi and flowed 290cfm intake and 175cfm exhaust @600 lift. Thats plenty enough for a 370-408ci engine making 475-500 hp.

I forgot to mention the valvetrain consists of AFM Hi-Rev Springs w/Comp titanium retains & keepers, Comp cams mechanincal lifters, Comp stud girdle & Comp Hardened Pushrods.

hrd2bslw

Your never going to know how much horsepower it can make without getting a tune.

As far as everything else goes. You can definatly run WAY more timing than 10* base with that straight race gas (upwards of like 18-20*) that 347 shouldn't rev more than 6500-6800rpm with those heads and cam. If it were a 302/306 motor than there would be a big difference going from 5800 to say 7000+ probably like 20-30rwhp depending on the air vilocity of the heads/intake.

If you bump the timing from 10* to around 18-20, scrap the mix in favor of straight race fuel, rev upwards of 6500+ and get a proper tune, you would probably see a 40-50rwhp increase. NOT FOR CERTAIN THOUGH.

Get it tuned and run it hard man!
Hey 92lx, Its been a while since you'v been on here, send me a pic of your car since you got the new welds on. Hows your baby girl doin?