Long post...What is needed to get this junk into the mid 12’s?

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Keith Morganstein
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Re: Long post...What is needed to get this junk into the mid 12’s?

Post by Keith Morganstein »

CamKing wrote: Fri May 03, 2019 10:10 am Wow. 18 pages on how to get a 3,400lb Nova into the mid 12's with a 355 SBC.

Next, we're going to have a 20 page thread, on how to make water, wet. :lol:
How do we make it :?: :lol:
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Re: Long post...What is needed to get this junk into the mid 12’s?

Post by PRH »

As for the stall speed and gears...... the way I look at it is....... if you’re chasing ET, for the most part, you want to run as much of both as you can stand(for your street car), up to what would be considered(or determined through testing) as “optimum” for the combination.
More gear/more stall also opens up the door for running more cam duration...... again, up to what would be optimum.

If you’re not going to optimize the stall and gearing, then you need to adjust you’re expectations...... and build....... accordingly.

If I were targeting 11’s with 3.73’s and a generic 10” converter, I’d go right to a longer crank.
Since it sounds like new pistons are now going to be part of the plan....... I’d pony up the little extra for the added stroke/cubes($214 in Summit right now).

Then the current heads are sized more correctly.
Somewhat handy with a die grinder.
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Re: Long post...What is needed to get this junk into the mid 12’s?

Post by PRH »

10.5:1 383 with some bowl ported Sportsman 2’s, decent intake and carb, small-ish street friendly solid cam...... easily in the 475-500hp range.
Somewhat handy with a die grinder.
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Re: Long post...What is needed to get this junk into the mid 12’s?

Post by GARY C »

travis wrote: Sat May 04, 2019 5:06 am Many of you guys have recommended a 4500 converter...how are these things on the street? He drives his car a lot so this is a concern. I’ve only owned 1 car with that loose of a converter and it sucked to cruise with (but was a riot when you hammered the throttle on street tires). It was a 10” ATI Streetmaster...not sure what the deal was as it wasn’t what I asked for when I ordered it but they tightened it up to a 3400 rpm flash stall and it was way better street driving and hooked better at the track. This was a stock suspension ‘78 nova with a 10.3-1 388 sbc with lightly ported 200cc pro-topline heads and a comp 294s.

Also...is 10.4-1 compression doable on pump gas with iron heads? The cam we are considering is similar to the cam that was in the good engine...248/254@.050, sft, on a 108 lsa.

The 3.73’s are staying for now, as I said the car sees a lot of street miles. He said he had 4.56’s in it years ago and didn’t like them.

I know there are a million different ways to get deep into the 12’s with a sbc, and that many of you wouldn’t build one this way, and that a lot tamer combo could be just as fast if not faster. However, he was happy with the way the good engine ran other than feeding it...I think that is what is most important.
My old combo like this had a 2800/3200 converter with 3.73 gear with about the same cam and compression, it will work as long as you take the time to tune it. This is the converter I have been looking at for a street project. https://www.jegs.com/i/JEGS/555/60429/10002/-1
I never ran nitrous on pump gas just for safety sake, I ran a separate 1 gallon cell and pump up front for nitrous but I know thats not in the budget at this point.
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Re: Long post...What is needed to get this junk into the mid 12’s?

Post by F-BIRD'88 »

https://www.high-performance-engines.co ... c64195.htm

These are a heck of a deal right now.
For a 350 or a 383....
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Re: Long post...What is needed to get this junk into the mid 12’s?

Post by GARY C »

F-BIRD'88 wrote: Sat May 04, 2019 5:06 pm https://www.high-performance-engines.co ... c64195.htm

These are a heck of a deal right now.
For a 350 or a 383....
Those are harmful to your health! :)

This is interesting. "100% AMERICAN Cast, Machined and Assembled Head" I wonder who and where they are cast?

I like the 195cc head for a street strip combo, possibly a little better air speed for the mostly low rpm driving.
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Re: Long post...What is needed to get this junk into the mid 12’s?

Post by F-BIRD'88 »

GARY C wrote: Sat May 04, 2019 5:38 pm
F-BIRD'88 wrote: Sat May 04, 2019 5:06 pm https://www.high-performance-engines.co ... c64195.htm

These are a heck of a deal right now.
For a 350 or a 383....
Those are harmful to your health! :)

This is interesting. "100% AMERICAN Cast, Machined and Assembled Head" I wonder who and where they are cast?

I like the 195cc head for a street strip combo, possibly a little better air speed for the mostly low rpm driving.
They appear to be a Profiler 23 head but without the D shaped exhaust port. (Headers)
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Re: Long post...What is needed to get this junk into the mid 12’s?

Post by GARY C »

F-BIRD'88 wrote: Sat May 04, 2019 5:42 pm
GARY C wrote: Sat May 04, 2019 5:38 pm
F-BIRD'88 wrote: Sat May 04, 2019 5:06 pm https://www.high-performance-engines.co ... c64195.htm

These are a heck of a deal right now.
For a 350 or a 383....
Those are harmful to your health! :)

This is interesting. "100% AMERICAN Cast, Machined and Assembled Head" I wonder who and where they are cast?

I like the 195cc head for a street strip combo, possibly a little better air speed for the mostly low rpm driving.
They appear to be a Profiler 23 head but without the D shaped exhaust port. (Headers)
Yes the chamber does look like a Profiler, thats what the Jeg's heads are, or at least last time I researched them.
Please Note!
THE ABOVE POST IN NO WAY REFLECTS THE VIEWS OF SPEED TALK OR IT'S MEMBERS AND SHOULD BE VIEWED AS ENTERTAINMENT ONLY...Thanks, The Management!
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Re: Long post...What is needed to get this junk into the mid 12’s?

Post by F-BIRD'88 »

Re driving with a 4500 stall converter on the street..
With this converter when accelerating from a stop normal PT driving expect the engine rpm to hug the 3000 rpm range as you accelerate, until you reach your intended cruising speed. +/- based on throttle input.
Yup more engine rpm flair,,, noise,,,
Accentuated more if combined with a lame- tame rear gear ratio...
Once you do reach your intended road cruise speed..
Eg: 30 mph...the engine rpm settles right down.
More noticable if going up a steep hill.
A rear gear ratio that more matches the car -engine for 1/4 mi drag use. :eg: 4.56, reduces the loose driving impression some at part throttle as the converter couples quicker as rpm climbs quicker.
The converter spends less time in "stall mode" during acceleration. Better converter overall efficientcy.
Takes a bit of driving the car around town to get accustomed to the new different driving impression.
The car still moves. The car still drives well on the street.
Increased transmission fluid temps... You want a good trans cooler that gets good airflow thru it while driving..
A trans temp guage is not a bad idea.
There is no free lunch..
Last edited by F-BIRD'88 on Sat May 04, 2019 6:05 pm, edited 1 time in total.
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Re: Long post...What is needed to get this junk into the mid 12’s?

Post by F-BIRD'88 »

GARY C wrote: Sat May 04, 2019 5:47 pm
F-BIRD'88 wrote: Sat May 04, 2019 5:42 pm
GARY C wrote: Sat May 04, 2019 5:38 pm

Those are harmful to your health! :)

This is interesting. "100% AMERICAN Cast, Machined and Assembled Head" I wonder who and where they are cast?

I like the 195cc head for a street strip combo, possibly a little better air speed for the mostly low rpm driving.
They appear to be a Profiler 23 head but without the D shaped exhaust port. (Headers)
Yes the chamber does look like a Profiler, thats what the Jeg's heads are, or at least last time I researched them.
The whole cylinder head looks exactly like the Profiler 23 head other than the stock oem shaped exhaust port.
Apparently oil drain back in the top of the heads has been improved also. IMHO Profiler is casting these heads.
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Re: Long post...What is needed to get this junk into the mid 12’s?

Post by BBO Omega »

As far as a 4000+ Converter used on the street, I had FTI restall my 2900 Coan 10” Converter to 4200. It drives exactly the same at part throttle as it did before. It requires a big load to flash to 4000+.
73 Omega, 468 BBO, 4.185 ICON Pistons,RR/Wenzler Heads with HS 1.7 rockers and PAC 1220X Springs,J&S 5-main Halo with Billet Caps, .590I .580E 242I 256E HR Cam, 1000hp Carb,2" x 3 1/2" headers,Coan 2900rpm Conv.,TH400,3.73 12 bolt,11.32/118
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Re: Long post...What is needed to get this junk into the mid 12’s?

Post by Ericnova »

It's been known since ATK came out with those that Profiler was the source. All ATK did was had them put a conventional location exhaust port in it.
It was posted in a thread a couple years back, along with info on the import Dart copy and the Blueprint Engines heads and ProMaxx heads.
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Re: Long post...What is needed to get this junk into the mid 12’s?

Post by F-BIRD'88 »

BBO Omega wrote: Sat May 04, 2019 10:00 pm As far as a 4000+ Converter used on the street, I had FTI restall my 2900 Coan 10” Converter to 4200. It drives exactly the same at part throttle as it did before. It requires a big load to flash to 4000+.
Thats because it is behind a big cid big torque engine.
Put the same converter behind a 350 cid sbc and it will
Strain tp max stall at 3500 rpm.
A converter made to stall at 4500 behind a 350 cid engine will be much looser...
The max stall of that 4500 stall (behind a 350 sbc) converter, if put behind your 468 BBO will now max stall at or close to 5500 rpm.
Yes it will still drive.
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Re: Long post...What is needed to get this junk into the mid 12’s?

Post by GARY C »

F-BIRD'88 wrote: Sun May 05, 2019 12:29 am
BBO Omega wrote: Sat May 04, 2019 10:00 pm As far as a 4000+ Converter used on the street, I had FTI restall my 2900 Coan 10” Converter to 4200. It drives exactly the same at part throttle as it did before. It requires a big load to flash to 4000+.
Thats because it is behind a big cid big torque engine.
Put the same converter behind a 350 cid sbc and it will
Strain tp max stall at 3500 rpm.
A converter made to stall at 4500 behind a 350 cid engine will be much looser...
The max stall of that 4500 stall (behind a 350 sbc) converter, if put behind your 468 BBO will now max stall at or close to 5500 rpm.
Yes it will still drive.
If you see that much of a change in converter rpm I would question the tolerance used in the converter, what you are describing would be something like a Boss Hogg or older TCI Street Fighter/Saturday night Special or what ever they are called, they got some or most of their stall increase with loose tolerance and bending fins as oppose to properly designed internals.

We have used a cpl of "Good" budget converters that were built correctly behind 306, 350's, 377, 382, 421's, 434's and BBC's 468 to 496... NA, Nitrous and small Blower as well as Small Blower with Nitrous and the stall/flash was within 100/200 rpm.

What you are describing we would call driving through the converter, that means it's time to rethink your converter combo or your converter builder. The only time we saw what you are explaining was when we went past what a "Good" budget converter could handle 500 to 700 inch Nitrous or Turbo anything done correctly... and you would normally find internal damage at that point due to overpowering it's build unless the tolerance was just so loose that it would bypass fluid and not damage the converter.
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Re: Long post...What is needed to get this junk into the mid 12’s?

Post by F-BIRD'88 »

The max stall you get from a converter is a direct function of the engine torque output applied.
There is about a 500 rpm difference in the max stall of a305 cid sbc vs a 350 cid engine.. With the same 10" converter.
3000 vs 3500 is typical.. Take that same 10" converter and put it behind a 454 bbc and the stall will be 4100-4200 rpm. This is how converters work.
Similar a 12" gm converter behind a 350 cid engine eill stall at 2100-2200 rpm.. Same 12" stock converter behind a 454 now, will stall at 2500-2600.
I have tested this myself eith varios gm converters behind various sbc and bbc engines.
GM defones this relationship as the "K Factor"
Thus if you know the GM K factor rating and know the engines torque output you can determine the stall speed rpm at max stall. More torque input gives higher max stall rpm from a perticular converter.
The newer GM torque converters have a 4 digit code on them. One of those digits in that code is the GM "K factor"
Google it.

Yes you can "blow right thru" a converter by applying too much torque input. Because the case distorts and the fluid cavitates. You can google that too. Fluid cavitation.
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