383 sbc first dyno experience

General engine tech -- Drag Racing to Circle Track

Moderator: Team

Erland Cox
Guru
Guru
Posts: 4142
Joined: Sun Jan 29, 2006 9:46 pm
Location: Lund in Sweden
Contact:

Re: 383 sbc first dyno experience

Post by Erland Cox »

steve cowan wrote: Fri Sep 16, 2022 5:29 pm
Erland Cox wrote: Fri Sep 16, 2022 9:35 am This is what I used with the filter and top on the dyno. + 25hp versus bare carb.

Image

A 4779 carb that I have ported the top of so it looks like a HP carb.

Erland
I am going to dyno another 383 I am building by the end of the year and would like to test the 2 set ups.
Erland,
On the road race vehicle is the drop base above the hood or below?
Next year I want go to a fibreglass/ carbon fibre hood and reverse cowl scoop for my car,one is for weight and the other is to get airfilter into a area not influenced by outside air due to vehicle speed travelling down the track.
I prefer that there is no under hood heat interference as well.
I tested without hood so in the real world the engine got hot air as the filter is under the hood.
But there are trays that isolate the filter and take the air in front of the hood.
They fit fine on my gen 3 Camaro but the engine is to far back in my gen 4.
I am taking the engine out of the gen 4. It was a class engine with unported heads based on a ZZ4 engine with hot cam,
longer rods, lighter pistons and more compression.
It made 395 hp and 550Nm:s.
I am taking the engine out for rebuilding and I will replace the heads with ported ones.
Just the same L98 heads and change of manifold to a Performer RPM.
The car has a Richmond super T10 and from the lot of broken gear boxes that came with the car more torque needs a stronger box.
We have very tight tracks in my part of the country anyway.
But I will be testing with cold air on my rolling road.

Erland
Erland Cox
Guru
Guru
Posts: 4142
Joined: Sun Jan 29, 2006 9:46 pm
Location: Lund in Sweden
Contact:

Re: 383 sbc first dyno experience

Post by Erland Cox »

steve cowan wrote: Wed Oct 05, 2022 3:59 am Wondering if aircleaner is a help or a hindrance??20221005_175728.jpg
You need a 14" filter to make that work.

Erland
skinny z
HotPass
HotPass
Posts: 2642
Joined: Tue Mar 11, 2008 8:42 am
Location: AB. CA.

Re: 383 sbc first dyno experience

Post by skinny z »

steve cowan wrote: Wed Oct 05, 2022 3:59 am Wondering if aircleaner is a help or a hindrance??20221005_175728.jpg
Why that particular filter element Steve?
Would a traditional 14x4 or 5 allow you to close the hood?

Below is a pic of a 14 x 4 on a 2" dropped base.
It fits under the short cowl hood on my 3rd gen Camaro. But barely.

wp_20170708_019_ea22a49fcca43a7d1da55338c8c77ae4d634c803.jpg
You do not have the required permissions to view the files attached to this post.
Kevin
ChopperScott
HotPass
HotPass
Posts: 594
Joined: Tue Nov 30, 2021 8:47 am
Location: West Milford, NJ
Contact:

Re: 383 sbc first dyno experience

Post by ChopperScott »

I'm using the 1/2" base spacer with a 14x3 filter. There's barely enough clearance, but provides a proper fit for the throttle linkage and hood...
Drop Base GP2.JPG
You do not have the required permissions to view the files attached to this post.
'73 Camaro Z/28 NETO/N
434 SBC 11:1, 1.294, 6.178 @ 108.87, 9.81 @ 134.93 (3060#, Naturally Aspirated, Sunoco Ultra 94)
Chopper Air Port 917-589-1278
steve cowan
Guru
Guru
Posts: 2253
Joined: Wed Jul 27, 2011 5:22 am
Location: brisbane AUSTRALIA

Re: 383 sbc first dyno experience

Post by steve cowan »

skinny z wrote: Wed Oct 05, 2022 8:24 am
steve cowan wrote: Wed Oct 05, 2022 3:59 am Wondering if aircleaner is a help or a hindrance??20221005_175728.jpg
Why that particular filter element Steve?
Would a traditional 14x4 or 5 allow you to close the hood?

Below is a pic of a 14 x 4 on a 2" dropped base.
It fits under the short cowl hood on my 3rd gen Camaro. But barely.


wp_20170708_019_ea22a49fcca43a7d1da55338c8c77ae4d634c803.jpg
My carb is level with top of hood with intakes and spacers I use,I lowered engine 1" last year to get crank centreline more in tune with pinion .
The cut hole in my steel hood has been like that for 15 years so I have a limited range for air filters.
As said previously I will be fitting a after market hood next year to make the drop base work with a reverse cowl scoop.
At this stage I am interested in dyno results as Erland had some good gains and looking on the google machine I see a lot of stock eliminatior vehicles using the same drop base setup.
steve c
"Pretty don't make power"
steve cowan
Guru
Guru
Posts: 2253
Joined: Wed Jul 27, 2011 5:22 am
Location: brisbane AUSTRALIA

Re: 383 sbc first dyno experience

Post by steve cowan »

I didn't want to clog up Kevin's thread on intake manifold so I have a couple of idea's for upgrades.
As mentioned on previous pages going to bigger comp roller
266 - 272 @ 0.050 "
Looking at the big trickflow intake manifold, I have not done proper measurements but it is 1206 felpro at the flange.
It would mean I need to open cylinder heads up to around 2.45"
I am thinking of making the throat the minimum CSA.
2.28" with valve stem calculated.
1.94" @ 89% probably keep 50 deg seat on intake but change exhaust seat to 52 degrees, again something to look at.
As per photos these cast iron heads are small but want to try welding up pinch area using AC TIG with aluminium/ nickel rod.
Never done before so plenty to consider.
I might also consider angle milling heads for a bump in compression, that's work I can't do so trying to find someone willing and able might be a issue but I will see I guess.
I suspect some people will think I am silly for going this route but I want to see where it goes positive or negative.
With bigger cam and induction tract peaks will be higher in the rpm range so I suspect I will be turning engine around 8000 rpm
Which will require a rear gear/ tyre change as well.
20221120_111437.jpg
20221119_163338.jpg
20221119_145706.jpg
20221119_145630.jpg
20220905_170417.jpg
I have a set of 1.6 - 1.6 jesel rockers with 0.300" offset on intake and using a 0.150" offset comp roller lifters as well.with the 3/8" pushrod it should clear.
I will look at going to a 1.7 - 1.5 shaft rockers set up if I can get offset I need.
The cost is pretty big and availability unknown at this stage.
You do not have the required permissions to view the files attached to this post.
steve c
"Pretty don't make power"
Elroy
Pro
Pro
Posts: 288
Joined: Tue Jul 16, 2019 12:46 pm
Location:

Re: 383 sbc first dyno experience

Post by Elroy »

steve cowan wrote: Mon Nov 21, 2022 5:24 am I didn't want to clog up Kevin's thread on intake manifold so I have a couple of idea's for upgrades.
As mentioned on previous pages going to bigger comp roller
266 - 272 @ 0.050 "
Looking at the big trickflow intake manifold, I have not done proper measurements but it is 1206 felpro at the flange.
It would mean I need to open cylinder heads up to around 2.45"
I am thinking of making the throat the minimum CSA.
2.28" with valve stem calculated.
1.94" @ 89% probably keep 50 deg seat on intake but change exhaust seat to 52 degrees, again something to look at.
As per photos these cast iron heads are small but want to try welding up pinch area using AC TIG with aluminium/ nickel rod.
Never done before so plenty to consider.
I might also consider angle milling heads for a bump in compression, that's work I can't do so trying to find someone willing and able might be a issue but I will see I guess.
I suspect some people will think I am silly for going this route but I want to see where it goes positive or negative.
With bigger cam and induction tract peaks will be higher in the rpm range so I suspect I will be turning engine around 8000 rpm
Which will require a rear gear/ tyre change as well.
20221120_111437.jpg
20221119_163338.jpg
20221119_145706.jpg
20221119_145630.jpg
20220905_170417.jpg
I have a set of 1.6 - 1.6 jesel rockers with 0.300" offset on intake and using a 0.150" offset comp roller lifters as well.with the 3/8" pushrod it should clear.
I will look at going to a 1.7 - 1.5 shaft rockers set up if I can get offset I need.
The cost is pretty big and availability unknown at this stage.
Sounds like a lot of work, but I think you would end up happy with the results. Nice that you still have the throat small. Does give you an opportunity to make the throat your minimum.......a lot of grinding and measuring :) cast iron :twisted:
Ohio HD
New Member
New Member
Posts: 2
Joined: Sun Feb 05, 2023 11:52 am
Location: Midwest

Re: 383 sbc first dyno experience

Post by Ohio HD »

KnightEngines wrote: Fri Aug 12, 2022 10:41 am
steve cowan wrote: Fri Aug 12, 2022 8:29 am Has anyone had any experience with total seal gas ported top ring?
I just ordered a set
1.2mm gas ported
1.5mm napier
3mm low tension
Looking at going back on the dyno after Xmas
Using same cylinder heads but will look at modifying with more porting, steeper valve job,angle mill for a bit more compression
A bit more camshaft as in duration around 250ish on intake lobe and as much lift as possible.
I just ordered a TFS 32400111 intake manifold that I will port as well.
My main interest at the moment is why engine lost power with more vacuum, and I am curious if the gas ported top ring will help with that .
Appreciate any feedback.
Steve - better to use actual gas ports, lateral works fine & they don't carbon up like vertical ports.
You want more cam, 250 @ .050 is a street cam!
You have 5000+ converter stall, you plain ol don't need to be shy with the cam, let it eat!
I'd jam a 268/274 on 109 in it with .440/.420 lobes.
Good afternoon. I know this post is a little old, but I'm searching for hands on experience with gas ported piston rings, and this post does touch the subject. Can I ask why it's suggested that lateral gas ports in the piston are a better solution than a top ring with gas ports (grooves)? In theory they both accomplish the same thing in almost the same way. Any help in understanding pros and cons with ported rings is appreciated.
DCal
Expert
Expert
Posts: 769
Joined: Fri Aug 11, 2006 11:37 am
Location: mooresville nc

Re: 383 sbc first dyno experience

Post by DCal »

Good afternoon. I know this post is a little old, but I'm searching for hands on experience with gas ported piston rings, and this post does touch the subject. Can I ask why it's suggested that lateral gas ports in the piston are a better solution than a top ring with gas ports (grooves)? In theory they both accomplish the same thing in almost the same way. Any help in understanding pros and cons with ported rings is appreciated.
[/quote]

My first thought is that if the piston gets the gas ports then the manufacturer gets your money and if they're in the ring the ring company gets your money.
This week I tore down my 565 which has been on the street 10 years (8000 miles) and the pistons have lateral gas ports. There is no signs of fuel washing around the ports, entering or leaving. In all honesty I can't say they were of any benefit or not. I am, however, ordering a new set of pistons without the gasports to see if there's any difference.
Ohio HD
New Member
New Member
Posts: 2
Joined: Sun Feb 05, 2023 11:52 am
Location: Midwest

Re: 383 sbc first dyno experience

Post by Ohio HD »

Ohio HD wrote: Sun Feb 05, 2023 11:59 am
Good afternoon. I know this post is a little old, but I'm searching for hands on experience with gas ported piston rings, and this post does touch the subject. Can I ask why it's suggested that lateral gas ports in the piston are a better solution than a top ring with gas ports (grooves)? In theory they both accomplish the same thing in almost the same way. Any help in understanding pros and cons with ported rings is appreciated.
DCal wrote: Sun Feb 05, 2023 3:35 pm My first thought is that if the piston gets the gas ports then the manufacturer gets your money and if they're in the ring the ring company gets your money.
This week I tore down my 565 which has been on the street 10 years (8000 miles) and the pistons have lateral gas ports. There is no signs of fuel washing around the ports, entering or leaving. In all honesty I can't say they were of any benefit or not. I am, however, ordering a new set of pistons without the gasports to see if there's any difference.
I suspect there's a lot of truth to just who gets the money. The pistons I have are prepped and ready to use, and I've thought of having lateral ports drilled. But I think I may just go with a new ported top ring from Total Seal. The good thing I guess is I only need two as this is a stroker motor for a Harley Davidson. I've read everything I can find regrading the ported (grooved) rings. I plan to call Total Seal tomorrow and speak to their tech department and see what they recommend.

My main goal is to reduce blow by potential as these motors don't deal well with excess crankcase pressure. It's already going to be increased as the motor is going from 96 cubic inched to 124 cubic inches. If I get a couple of horsepower in the process that's all good too.

Image

Image

Image
Bigchief632
Pro
Pro
Posts: 449
Joined: Tue Aug 09, 2022 9:20 am
Location: US

Re: 383 sbc first dyno experience

Post by Bigchief632 »

DCal wrote: Sun Feb 05, 2023 3:35 pm Good afternoon. I know this post is a little old, but I'm searching for hands on experience with gas ported piston rings, and this post does touch the subject. Can I ask why it's suggested that lateral gas ports in the piston are a better solution than a top ring with gas ports (grooves)? In theory they both accomplish the same thing in almost the same way. Any help in understanding pros and cons with ported rings is appreciated.
My first thought is that if the piston gets the gas ports then the manufacturer gets your money and if they're in the ring the ring company gets your money.
This week I tore down my 565 which has been on the street 10 years (8000 miles) and the pistons have lateral gas ports. There is no signs of fuel washing around the ports, entering or leaving. In all honesty I can't say they were of any benefit or not. I am, however, ordering a new set of pistons without the gasports to see if there's any difference.
[/quote]

I've noticed on vertical gas ported pistons, on engines i've done, taking them apart after running awhile, there is marks in the chamber/quench area in a circle, where there is little round spots that correspond to the gas ports in the pistons, so something is happening.
Maximum power using simple logic and common sense
KnightEngines
Guru
Guru
Posts: 2682
Joined: Fri Jan 09, 2009 8:51 pm
Location: Australia

Re: 383 sbc first dyno experience

Post by KnightEngines »

Ohio HD wrote: Sun Feb 05, 2023 11:59 am
KnightEngines wrote: Fri Aug 12, 2022 10:41 am
steve cowan wrote: Fri Aug 12, 2022 8:29 am Has anyone had any experience with total seal gas ported top ring?
I just ordered a set
1.2mm gas ported
1.5mm napier
3mm low tension
Looking at going back on the dyno after Xmas
Using same cylinder heads but will look at modifying with more porting, steeper valve job,angle mill for a bit more compression
A bit more camshaft as in duration around 250ish on intake lobe and as much lift as possible.
I just ordered a TFS 32400111 intake manifold that I will port as well.
My main interest at the moment is why engine lost power with more vacuum, and I am curious if the gas ported top ring will help with that .
Appreciate any feedback.
Steve - better to use actual gas ports, lateral works fine & they don't carbon up like vertical ports.
You want more cam, 250 @ .050 is a street cam!
You have 5000+ converter stall, you plain ol don't need to be shy with the cam, let it eat!
I'd jam a 268/274 on 109 in it with .440/.420 lobes.
Good afternoon. I know this post is a little old, but I'm searching for hands on experience with gas ported piston rings, and this post does touch the subject. Can I ask why it's suggested that lateral gas ports in the piston are a better solution than a top ring with gas ports (grooves)? In theory they both accomplish the same thing in almost the same way. Any help in understanding pros and cons with ported rings is appreciated.
The gas ported rings are stupid $$.
Go with lateral gas ports, then at freshen time you're just replacing regular rings.
Definitely worth it, even on a twin you'll see a couple HP gain & reduced blowby.
Dave B
Pro
Pro
Posts: 333
Joined: Fri Jan 20, 2023 10:07 am
Location: Midwest

Re: 383 sbc first dyno experience

Post by Dave B »

Nice ride!Is this solid roller cam?Didn't see mention or spring pressure etc.
DCal
Expert
Expert
Posts: 769
Joined: Fri Aug 11, 2006 11:37 am
Location: mooresville nc

Re: 383 sbc first dyno experience

Post by DCal »

Dave B wrote: Mon Feb 06, 2023 11:23 am Nice ride!Is this solid roller cam?Didn't see mention or spring pressure etc.
If this is for DCal, It's a Comp hyd roller 242/248 @ .050. 114 in at 110, .653 lift , iirc springs are 145 lbs Made 721hp/689tq quite easily. Currently putting in a 400 sb with A/C for cruising this summer.
Dave B
Pro
Pro
Posts: 333
Joined: Fri Jan 20, 2023 10:07 am
Location: Midwest

Re: 383 sbc first dyno experience

Post by Dave B »

Deal
No I was asking about 383.I should of ask that by his name .My bad
Post Reply