UPDATE to HP numbers

[David V]

Final Dyno run on my 350 today ... changed to Pentronics ignition and added a 1" spacer under the carb:

Torque
370 3200
391 4700
372 5000

HP
333 4500
376 5500
367 5700

Should be a little more when my I get my carb done by Osborne!

Any thoughts?

[GSXMEN]

Looking good David!:TU:

Keep us posted with your tuning progress. Pretty good HP #s for a street motor!:)

[72skylark]

so what is the build up?
was this engine dyno or chassis dyno?

[brblx]

dumb question #439: what's the purpose of the carb spacer?

[GSXMEN]

David,

Some motors respond better with or without carb spacers. Some work with an open spacer, while some like the 4 hole spacers. Unfortunately, it's kind of a trial and error sort of thing. Adding a spacer increases the overall plenum size of the intake. Basically, you need to see what will work for your combo. I've seen alot of Pontiacs that really wake up with a 2" open spacer. Some motors fall on their face with ANY kind of spacer.

Some of the better tuners on the board can probably narrow things down a little better for you. I don't believe anything is set in concrete, though.

[David V]

Any thoughts on how much nitrous this engine should handle ??

The engine was engine Dyno'd

Specs as follows:

72 block decked
74 heads cut and ported
74 polished rods ARP bolts
forged pistons .. actual CR 10.5-1
GS118 cam
780 q-jet
stock dist. w/pentronics and curved
TA intake w/spacer
Poston headers

Still needs Osborne Carb

Will run Nitrous after I run the car some.

[Mike T]

Hmmm. 376 bhp + 8psi intercooled boost=560-630bhp?

Michael Tweedy
xsperformance@iwon.com

[David V]

Mike ... will it hold together at 560hp?

David

[Mike T]

Pistons should be ok, my biggest concern would be the rods. Using reconditioned capscrew rods with ARP rod bolts, I would feel more comfortable around 450-500bhp. Main cap & TA undercut head studs would be a good idea also.

Someone needs to figure out how to make a set of good forged rods for the 350 for around $500.00 or billet for $800.00. I feel good rods, lightweight JE pistons (which already exist) and block girdle with studs would support 650bhp.

But for the meanwhile, call it 5psi & 500-525bhp. I have found that intercooled centrifugal boost seems to be much easier on the engine than nitrous, regardless of the power level.

Michael Tweedy
xsperformance@iwon.com

[David V]

Mike,

Let me know when, number 2 350 is waiting for next project for my 70 GS350??

David

[Mike T]

If you mean when the blower kit will be available it looks like it is right around the corner. :grin:

Michael Tweedy
xsperformance@iwon.com

[GSXMEN]

Mike - The girdled turbo v-6's are in the 700hp territory. I think the 350 CAN be built to take more - based on what the v6 guys are doing.

[Mike T]

Sure, just depends on how much margin you want in your engine.

It MAY be possible that the 350 block could handle MORE power as it is using 8 cylinders rather than 6. Of course, until some folks start getting into that area its all hypothetical. Depending on how well the Supercharger project goes, we may just push an engine that hard. The blower can definitely make the power, as it overcomes the limitations of the head to some degree.

Michael Tweedy
xsperformance@iwon.com

[GSXMEN]

Once we get a girdle for the 350, I think the block will be fine. I think we need to address the rod 'issue' before we can get past the 600+hp range!

After we get a girdle and some billet rods...Watch Out!!:grin:

[Mike T]

Billet rods are already available, its just that they cost $1100!

Michael Tweedy
xsperformance@iwon.com