650+HP BBc

[EZ Nova]

Just wondering here, might get into the business of building and selling some BBc engines, nothing crazy just like say 650Hp pump-gas with dual-plane "198" style intakes.

Just looking at the market. We have just did a 468 with closed chamber LS-6 heads and "198" intake and it made 709Hp@6100 and 730Ft/lbs@4800 with 94 Octane pump gas. Looking at what GM get's for their "crate" 572's that don't make the power we can (not saying they can't. BUT there 572/720 is also 12-1 and with a dominator and single plane intake).

In a '68-'72 style Nova, we are thinking these would run well into the 9's and still look mostly OEM but for headers.

Now even thought these motor don't make a lot of hp by today's standards, most would struggle to get that with a dual-plane intake. So since we done the R&D on these, might be time to move onto different endeavours.

Thanks John

[VintageMusclecar]

That's nearing 120% VE--on pump gas--and 1.56 lb.ft per cubic inch. NHRA Pro Stock engines are just over 1.6 lb.ft per cubic inch.

If I may ask--what cam, compression and how much head work?

[bigsixman]

709 hp @6100 rpm and 730 lb ft @ 4800 rpm with a 468" closed chamber bbc on 94 pump gas is too high. I question those numbers with that 468" bbc combination as it appears to be happy dyno numbers.

A good friend of mine has a 10.25 compression 505" cc bbc with a Dart intake with a 1050 dominator with # 840 cc cast iron heads and a small .640" roller and on 91 pump gas and it makes 647 hp.

[PxTx]

I trust John's numbers are real. It think the speculation should be taken as a compliment for achieving pump gas numbers which seem to have shattered what was perceived as the ceiling for that combination.

The bore prep, rings and piston selection play an equally important role as cam choice- but they don't hold all the secrets to making that kind of power. It really is the entire package. I would love to hear more about it John. Whatever you are willing to open up on is great, but in a post about gauging interest- I'm not expecting free speed secrets.

[VintageMusclecar]

To put this in comparison, Mark Jones' 700 HP <span style="font-weight: bold">496</span> <span style="text-decoration: underline">oval port</span> motors are only making 675 lb.ft of torque, which is 1.36 lb.ft per cubic inch. Mark is arguably one of the best Big Block Chevy builders in the country, and his engines back the dyno #'s up at the track (when the car they reside in is dialed in of course).

Sorry, but 730 lb.ft out of a 468 at only 4800 rpm on pump gas is more than a little hard to believe. I would be looking VERY hard at the dyno calibration.

Here's a little something to consider from an elite engine builder, Darin Morgan of Reher &amp; Morrison:

From Yellowbullet:

<span style="font-style: italic">&quot;I have looked through this thread and never saw an answer to your question regarding MAX ft/lbs per-cid. For gasoline engines the max is 1.67ft/lbs per-cid. If anyone tells you they are making more, they are fibbing to you. That equates to about 120% to 124% volumetric efficiency &quot; Trapped&quot; which is where Pro Stock and Comp engines have been at for the last 20+ years. P/S and Comp engines all make about 1.65ft/lbs per-cid. The game is to raise that peak TQ to higher an higher engine speeds creating more HP.

Here is another fact. A good engine will only fall 50ft/lbs from peak TQ to peak power. Bracket engines that make about 1.45ft/lbs per-cid all fall about 60 ft/lbs from Tq peak to power peak over there power band. If they fall more than that it indicates a problem in the tuning or the engines design or combination.'</span>

Link to post

Link to thread

Not trying to be a dick, but the numbers just do not add up (no pun intended).

[EZ Nova]

Your RIGHT. The dyno sheet is being sent over. This is a customer's motor. Mine will be a bit more than this. BUT IT'S MINE AND IF THE &quot;052&quot; ZL-1 BLOCK WILL HOLD IT, it should make substantially more Hp and a bit more tq.

Now guys want to talk about VE (Volumetric Efficiency), well my OTHER motor is just over 120 V.E. It's under 500 C.I. and DID make 1274Hp and 824Tq. As you can see, we too can make power.




YES I too know Mark Jones and have spoken too him on a few occasions. Mark does well with those 496 combo's. We too have 496's that not only make over 700hp, but have run couple thousand miles all the while getting some fuel economy. But we use sq port OEM heads and OEM intakes.

[EZ Nova]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bigsixman</div><div class="ubbcode-body">709 hp @6100 rpm and 730 lb ft @ 4800 rpm with a 468&quot; closed chamber bbc on 94 pump gas is too high. I question those numbers with that 468&quot; bbc combination as it appears to be happy dyno numbers.

A good friend of mine has a 10.25 compression 505&quot; cc bbc with a Dart intake with a 1050 dominator with # 840 cc cast iron heads and a small .640&quot; roller and on 91 pump gas and it makes 647 hp. </div></div>

So here is the ACTUAL dyno sheet:

[VintageMusclecar]

Just out of curiosity, do you have the observed (uncorrected) dyno sheet available? If not, do you know what the correction factor was?

Looks like you still have some power left on the table as well--that oil pressure fluctuation is a dead give-away there's some windage issues. What pan was on it?

[EZ Nova]

Vintage, you need to look at the whole thread over on that site.

Star Racing George Bryce:

&quot;Torque..is not because of stroke , bore or valve size.
It is from &quot;trapping&quot; ability....
If we trap more mixture and light it..it will make more torque.

Some good examples....

Our 528 Hemi makes 670 lbs feet @ peak = 1.26 with street cam
Our NHRA 160 cube twin makes 230 LBS FT = 1.43
Our Suzuki 1750cc (106) cubes makes 160 lbs feet = 1.51

Guess which motor has the shortest duration cam?&quot;

AND

&quot;I want to add...all of my race engines operate above peak torque...like the 160 twin, we run it from 9000 to 10000...we never see peak tq.
We run the Zook from 12000 till 14000...both of them have peak torque below our racing range.

The 500 inch PS NHRA engines run way higher up than where peak tq is also.
ALL engines have the same horse power and the same torque at 5252 RPM.
Well designed engines have more Torque below 5200 rpm than the HP.
AS well designed engines have more HP than TQ after 5200 RPM.

More teasers&quot;

Now notice what George said above last line, &quot;Well designed engines have more Torque below 5200 rpm than the HP.
AS well designed engines have more HP than TQ after 5200 RPM.&quot; Is that not EXACTLY where this 468 make the change to HP being higher then Tq.

[EZ Nova]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: pxtx</div><div class="ubbcode-body">I trust John's numbers are real. It think the speculation should be taken as a compliment for achieving pump gas numbers which seem to have shattered what was perceived as the ceiling for that combination.

The bore prep, rings and piston selection play an equally important role as cam choice- but they don't hold all the secrets to making that kind of power. It really is the entire package. I would love to hear more about it John. Whatever you are willing to open up on is great, but in a post about gauging interest- I'm not expecting free speed secrets. </div></div>

Ok, since as people can see here, some of my &quot;friends&quot; over on YB and Speedtalk give away some info, I will too!

Pistons in our stuff so far has been ONE-OFF with our designs by JE. These motors are NOT cheap, and infact for what there worth, you could probably get more power with different parts. It's just the WAY that one get power and what one is looking for. These are pump-gas friendly, but would run better if we put &quot;race&quot; gas into them. But were doing this to prove that you CAN make power with these motors. This 468 is a Scat rotating assembly with our piston, some details in the short. Wet sump and NO vac pump. Solid roller over 700 and lobes that WILL live on the street and lifter that CAN idle. I &quot;recall&quot; these were 291 '70 heads?? But that I don't recall. There is LOTZ of time into the whole induction package. That goes basically from CRANK to air cleaner on there. Stroke is a given, then we work with rod length and piston comp height. It's a whole package. Even valve took a month to figure out right. It's all work and R&amp;D.


For example, my ZL-1. We just spent 18 hrs fine tuning my &quot;198&quot; intake and got 3+ CFM BUT were are now within 2% from runner to runner on a SF600. My motor WILL make significantly more HP then this 468. Just worried about the block IF it will seal.