Author Topic: Tens on motor  (Read 910 times)

Garry

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Tens on motor
« on: May 09, 2019, 01:31:38 PM »
Or am I asking for to much out of a Pontiac?
« Last Edit: May 10, 2019, 05:01:29 PM by Garry »

oldskool

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Re: Tens on motor
« Reply #1 on: May 11, 2019, 07:33:21 AM »
There are a LOT of variables, as I'm sure you know.

But, there are quite a few 400 & 455 powered Stockers running mid to high 10's, with unported iron heads, iron intake, 750 Q-jet, & low lift flat tappet cam.

Several Super Stockers have run 9's, with iron heads, & 750 Q-jet. Quite a few have run 9's with the alum head 428 & 750 Q-jet.

These are obviously drag only cars. So, if you are trying to do it with a heavy car, and trying to keep it streetable, that will take a little more power. More cubes make it easier. Can build a stock block engine to around 500 cubes. If your budget will allow, an aftermarket block will allow well over 500 cubes. 

So, basically, your budget is the biggest ET limiter.   
« Last Edit: May 11, 2019, 07:47:04 AM by oldskool »

oldskool

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Re: Tens on motor
« Reply #2 on: May 11, 2019, 12:46:57 PM »
I can't say exactly what it would take to get your car to the performance level you want.

My engine guy built a factory block 4.5" stroker, with KRE High Port heads, a solid roller cam, a Northwind intake, & a Dominator carb, on E85. It made 755hp @ 5900 rpm, and around 700 peak torque.

But, if you wanna go 10's with iron heads, a Q-jet, a HFT cam, & 92 octane pump gas, THAT will take a little more planning.

If you wanna talk to some guys with factory block 10 sec cars, go to the PY forum.

oldskool

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Re: Tens on motor
« Reply #3 on: May 11, 2019, 12:59:32 PM »
"...it might be time to go LS.


Most low budget guys who wanna go fast have always gone with Chevy power. Chevy parts have always been cheaper, because of mass production of aftermarket parts. When it comes to price per horsepower, it's not even close--no contest.

So, if your budget won't build a high power Pontiac engine, you'll just have to switch, I suppose. May as well go with a light Chevy body too. I've read that every 100lbs = about 1/10 of a sec in ET. There is an alum head 428 Pontiac powered Cobalt that has gone high 8's. It's the quickest Pontiac powered Super Stocker I know of. Lighter is quicker.
« Last Edit: May 11, 2019, 01:03:22 PM by oldskool »

Garry

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Re: Tens on motor
« Reply #4 on: May 12, 2019, 03:38:43 PM »
I've been thinking about a 4.5 crank. I've got a 4.25 in there right now. I'd need a new set of pistons but the rods would still work.

Re: Tens on motor
« Reply #4 on: May 12, 2019, 03:38:43 PM »

79T/Aman

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Re: Tens on motor
« Reply #5 on: May 18, 2019, 04:00:31 PM »
that is kind of a loaded question, how's your chassis? if you can't put the power to the ground well....
www.pro-touringf-body.com  your source for making your Trans am do what it does best!......SHOW OFF!

Garry

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Re: Tens on motor
« Reply #6 on: May 20, 2019, 03:07:56 AM »
The chassis gets better all the time. It'll dead hook at the track and I can spray it into the 10s.
« Last Edit: May 20, 2019, 03:09:42 AM by Garry »

Aus78Formula

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Re: Tens on motor
« Reply #7 on: May 21, 2019, 11:31:22 PM »
Further lightening? Diet for driver?!

79T/Aman

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Re: Tens on motor
« Reply #8 on: May 22, 2019, 07:56:35 AM »
I'm a bit confused, wasn't the first post asking if it could be done or was it just a conversation starter?

Did you get those heads used? E-heads don't have heart shaped chambers unless they were modified, and I sure would have them decked for flatness as it looks like someone took a Rollock to the deck.

I also notice the block still has press in galley plugs and you really need to install longer main cap dowel pins, at that power level you will have main cap walk and screw up your bearings.
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Garry

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Re: Tens on motor
« Reply #9 on: June 25, 2019, 06:33:15 PM »
The CNC Edelbrocks have heart shaped combustion chambers.

1979 Black and Tan

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Re: Tens on motor
« Reply #10 on: June 26, 2019, 11:25:51 AM »
with an LT9 you will
1979 Trans Am
100% California Car, originally Atlantis Blue/ Black...All Original Unmolested 403, TH350, 2.41
63,300 orig. miles
1971 Chevy K20 4x4

Garry

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Re: Tens on motor
« Reply #11 on: July 01, 2019, 01:01:03 AM »
I'll probably just get back to car shows and call it a day. Thanks for the help guys.

DynoLee

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Re: Tens on motor
« Reply #12 on: July 01, 2019, 02:15:16 AM »
Have you ever spent a day testing & tuning on a chassis dyno?  A good wideband used with a day on a chassis dyno can be quite rewarding, in my experiences.  I've seen gains over 60rwhp several times.

Just tweaking the lash settings from what was on the card, making one or 2 thou changes, gained me 15rwhp at peak and 25rwhp around 4500. I went from .026/.026 and ran best at .021/.024.

One dyno session showed that the aircleaner assembly was costing 35rwhp.  Another suggested that the mufflers (Flowmasters) had gone funky - changed mufflers and picked up 40rwhp by 5200rpm.

Are you racing at a higher altitude, and are your times "corrected"?  I know normally aspirated cars in Denver are around a second slower than at where I am (sea level).  I looked at some of your posts, and have an idea of what parts you have.  You've got  WAY bigger/"better" stuff than I had when I was running 11.2's at nearly 120mph in street trim, N/A, with my old Firebird.  Other than altitude, I have to think that you either have a tuning issue or some part of your system is bottlenecking the power.

I do think your cam has way too much intake duration.

DynoLee

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Re: Tens on motor
« Reply #13 on: July 01, 2019, 08:01:32 AM »
I think it was the old cam that was bottle necking the power. You sound like you know what you're talking about. It's never been on any kind of dyno.

If you ever decide to dyno, I suggest using a DynoJet.  Take a USB drive with you, and have them copy your run data to that drive.  Then, you can send that data to me and I can analyze it a bit further.  Make sure they hook up the tach lead, so that it is recording RPM.  I rarely find less than 10rwhp when I dyno tune a car.  20-30 is rather typical.  I bet there is at least 50 to be found with your combo.

Here is some data on my old Firebird, that I mentioned above:  http://www.pontiacstreetperformance.com/psp/rebuild45500.html   Looking at that, I'm not sure why we never updated the info.  I think that is where the car was in 2001.  After spending  a few hours on a dyno, playing with the timing and jetting, I ran a bit over a tenth/1mph better.  I then added an electric fan and water pump, eliminating the mechanical versions, and improved roughly another .1/1.

In 2005 I swapped to a solid flat tapped cam, 247/247 @ .050, 108lsa installed at 109, along with a fresh valve job and new valve springs, and ran 11.3's.  I then replaced the old Flowmasters with Goerlich straight-through mufflers.  WAY quieter with the new mufflers!  At that point it ran 11.27 at just under 120mph.  At that point I was going through a divorce, and somebody made me an offer on the car, so I sold it....  :-/

Garry

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Re: Tens on motor
« Reply #14 on: July 02, 2019, 01:37:50 PM »
What I'd like to do is dyno the motor with 1.65 rockers then do it again with a set of 1.5

The cam was spec'd out for 1.65s

If I lower the lift it seems it would have a similar effect as lowering the duration.

Re: Tens on motor
« Reply #14 on: July 02, 2019, 01:37:50 PM »



Garry

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Re: Tens on motor
« Reply #15 on: July 02, 2019, 01:49:46 PM »
I'd still be a hair over 600 lift with 1.5 rockers

DynoLee

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Re: Tens on motor
« Reply #16 on: July 02, 2019, 06:36:29 PM »
I'd still be a hair over 600 lift with 1.5 rockers

That would be a great experiment to perform on a chassis dyno.  Maybe change all the intakes first & test, then do the exhaust.

Only concern would be if the rockers are different brands, then they may need different length pushrods.

Also if it makes more power with larger lash, that may suggest the cam is too big.

Garry

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Re: Tens on motor
« Reply #17 on: July 24, 2019, 01:20:15 AM »
I went with the 1.65 rockers.

<a href="http://www.youtube.com/watch?v=5oED8e_0i1o" target="_blank">http://www.youtube.com/watch?v=5oED8e_0i1o</a>

DynoLee

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Re: Tens on motor
« Reply #18 on: July 25, 2019, 07:41:21 AM »
Sounds GREAT!!

Garry

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Re: Tens on motor
« Reply #19 on: July 26, 2019, 02:18:37 AM »
Thanks Lee, I'm pretty happy with it. If it can't hit 10s on motor I don't know what to say.

DeCaff2007

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Re: Tens on motor
« Reply #20 on: August 01, 2019, 07:42:36 AM »
PMed you.
1976 T/A 400, 4-speed swap.... 

Check out my resto thread:  http://transamcountry.com/community/index.php?topic=48626.0

It's all trial and error until something lines up...

Re: Tens on motor
« Reply #20 on: August 01, 2019, 07:42:36 AM »
You can help support TAC!