1986 iron head l98 corvette valve spring question

Indycars · Dec 30, 2019

Give me as much info as you can and I would be happy to do a simulation for you.

Bore & Stroke:
Displacement: cubic inches
Rod Length:
Heads Make/Model with flow numbers: Flow (CFM) at several lift points.
Combustion Chamber Size in CC’s:
Dome Volume: For a domed piston use a (-) negative number.
Valve Reliefs Volume: For a piston with valve reliefs or dish, use a (+) positive number.
Deck Clearance:
Head Gasket Bore:
Head Gasket Thickness:
Valve Sizes Intake/Exhaust:
Intake Manifold Model Type: [Single or Dual Plane]
Model #:
Carburetor Size or EFI (CFM):
Blower/Turbo Make/Model:
Belt Ratio:
SCR & DCR: Or the info to calculate SCR & DCR [ http://garage.grumpysperformance.co...comp-ratio-cranking-pressure-calculator.4458/ ]
Header Tube Diameter: Small, Medium, Large (1-5/8", or , or)
Cam Card: Need all 8 valve timing events at seat-to-seat and at 0.050”, lobe lift.
Rocker Ratio, Intake/Exhaust:
Cam Installed per Cam Card, or Retarded or Advanced:
Fuel Used: Gasoline, Methanol, Ethanol, E85 .....

Jeremyd0813 · Dec 30, 2019

Indycars said:
Give me as much info as you can and I would be happy to do a simulation for you.

Bore & Stroke:
Displacement: cubic inches
Rod Length:
Heads Make/Model with flow numbers: Flow (CFM) at several lift points.
Combustion Chamber Size in CC’s:
Dome Volume: For a domed piston use a (-) negative number.
Valve Reliefs Volume: For a piston with valve reliefs or dish, use a (+) positive number.
Deck Clearance:
Head Gasket Bore:
Head Gasket Thickness:
Valve Sizes Intake/Exhaust:
Intake Manifold Model Type: [Single or Dual Plane]
Model #:
Carburetor Size or EFI (CFM):
Blower/Turbo Make/Model:
Belt Ratio:
SCR & DCR: Or the info to calculate SCR & DCR [ http://garage.grumpysperformance.co...comp-ratio-cranking-pressure-calculator.4458/ ]
Header Tube Diameter: Small, Medium, Large (1-5/8", or , or)
Cam Card: Need all 8 valve timing events at seat-to-seat and at 0.050”, lobe lift.
Rocker Ratio, Intake/Exhaust:
Cam Installed per Cam Card, or Retarded or Advanced:
Fuel Used: Gasoline, Methanol, Ethanol, E85 .....

1. 4.00 bore / 3.48 stroke
2. 350ci
3. 5.700 rod length
4. Afr 190 vortec (flow sheet attached)
5. 65cc combustion chamber
6. Flat top with 5cc valve reliefs
7. .020 deck
8. 4.166 head gasket bore
9. .041 head gasket compressed thickness
10. 2.02 in valve / 1.60 ex valve
11. Single plane with 835cfm throttle body (efi)
12. 9.67 scr and 9.10 dcr
13. 1 3/4 long tube headers
14. Cam card attached
15. 1.6 rocker ratio on in/ex
16. Cam installed per card
17. Gasoline fuel

I tried to get as much as I could and thankyou very much for taking the time to do this.

Jeremyd0813 · Dec 30, 2019

Jeremyd0813 said:
1. 4.00 bore / 3.48 stroke
2. 350ci
3. 5.700 rod length
4. Afr 190 vortec (flow sheet attached)
5. 65cc combustion chamber
6. Flat top with 5cc valve reliefs
7. .020 deck
8. 4.166 head gasket bore
9. .041 head gasket compressed thickness
10. 2.02 in valve / 1.60 ex valve
11. Single plane with 835cfm throttle body (efi)
12. 9.67 scr and 9.10 dcr
13. 1 3/4 long tube headers
14. Cam card attached
15. 1.6 rocker ratio on in/ex
16. Cam installed per card
17. Gasoline fuel

I tried to get as much as I could and thankyou very much for taking the time to do this.

Acou

Indycars said:
Give me as much info as you can and I would be happy to do a simulation for you.

Bore & Stroke:
Displacement: cubic inches
Rod Length:
Heads Make/Model with flow numbers: Flow (CFM) at several lift points.
Combustion Chamber Size in CC’s:
Dome Volume: For a domed piston use a (-) negative number.
Valve Reliefs Volume: For a piston with valve reliefs or dish, use a (+) positive number.
Deck Clearance:
Head Gasket Bore:
Head Gasket Thickness:
Valve Sizes Intake/Exhaust:
Intake Manifold Model Type: [Single or Dual Plane]
Model #:
Carburetor Size or EFI (CFM):
Blower/Turbo Make/Model:
Belt Ratio:
SCR & DCR: Or the info to calculate SCR & DCR [ http://garage.grumpysperformance.co...comp-ratio-cranking-pressure-calculator.4458/ ]
Header Tube Diameter: Small, Medium, Large (1-5/8", or , or)
Cam Card: Need all 8 valve timing events at seat-to-seat and at 0.050”, lobe lift.
Rocker Ratio, Intake/Exhaust:
Cam Installed per Cam Card, or Retarded or Advanced:
Fuel Used: Gasoline, Methanol, Ethanol,

All set...

Indycars · Dec 30, 2019

Thank you for pulling all this good info together in one place, it makes my job a lot easier. And I
make fewer mistakes this way!

If you can use Excel, then use the link to determine SCR/DCR.
http://garage.grumpysperformance.co...comp-ratio-cranking-pressure-calculator.4458/

If you know the camshaft part number and manufacture, I can add it to my inventory so I don't have to do it again?

If you know the head part number and manufacture, I can add it to my inventory so I don't have to do it again? ... thanks!

Jeremyd0813 · Dec 30, 2019

There correct now, used the Wallace racing calculators and the cam is a custom grind cam that they reccomend. And the scr 9.67 and dcr of 9.10

Jeremyd0813 · Dec 30, 2019

Indycars said:
Thank you for pulling all this good info together in one place, it makes my job a lot easier. And I
make fewer mistakes this way!

If you can use Excel, then use the link to determine SCR/DCR.
http://garage.grumpysperformance.co...comp-ratio-cranking-pressure-calculator.4458/

If you know the camshaft part number and manufacture, I can add it to my inventory so I don't have to do it again?

If you know the head part number and manufacture, I can add it to my inventory so I don't have to do it again? ... thanks!

And not sure of a part number, right on air flow research site doesnt really list one other than sbc 190 vortec head.

Indycars · Dec 30, 2019

Appreciate your effort to find the part number!

JSYK, It's going to be tomorrow, mid morning before I have questions or the simulation to post.

JSYK = Just So You Know

Jeremyd0813 · Dec 30, 2019

Indycars said:
Appreciate your effort to find the part number!

JSYK, It's going to be tomorrow, mid morning before I have questions or the simulation to post.

JSYK = Just So You Know

No problem at all, and I'll try to get more info on parts numbers for ya. For the cam and head...see what I can find

Jeremyd0813 · Dec 30, 2019

Indycars said:
Appreciate your effort to find the part number!

JSYK, It's going to be tomorrow, mid morning before I have questions or the simulation to post.

JSYK = Just So You Know

Ok for the heads jegs, summit etc refers to them as afr 912 heads (afr sbc eliminater vortec heads) and took a pic of different specs as well just in case u need it for anything.

Grumpy · Dec 30, 2019

Head Gasket Roughness (ra)

I've installed my heads now, getting ready for when the headers come back. I noticed the surface finish of the aluminum heads, they seemed to be very rough. But what is rough, how do you quantify roughness ??? Try telling your buddy what you mean when you say "it was very rough". The most...

garage.grumpysperformance.com

http://garage.grumpysperformance.com/index.php?threads/sbc-head-gasket-choice.11070/#post-79067

http://garage.grumpysperformance.com/index.php?threads/head-gasket-related.1859/#post-50617

http://garage.grumpysperformance.com/index.php?threads/head-gasket.10085/#post-39429

http://garage.grumpysperformance.co...ad-gasket-for-aluminum-heads.4403/#post-26317

http://garage.grumpysperformance.co...asket-bore-size-vs-bore-size.2681/#post-11603

Jeremyd0813 · Dec 30, 2019

Indycars said:
Thank you for pulling all this good info together in one place, it makes my job a lot easier. And I
make fewer mistakes this way!

If you can use Excel, then use the link to determine SCR/DCR.
http://garage.grumpysperformance.co...comp-ratio-cranking-pressure-calculator.4458/

If you know the camshaft part number and manufacture, I can add it to my inventory so I don't have to do it again?

If you know the head part number and manufacture, I can add it to my inventory so I don't have to do it again? ... thanks!

Jeremyd0813 · Dec 30, 2019

Indycars said:
Appreciate your effort to find the part number!

JSYK, It's going to be tomorrow, mid morning before I have questions or the simulation to post.

JSYK = Just So You Know

Also I tried to you that program and downloaded everything but it's off by 1° from my cam spec sheet, but there specs are at .004 or .050 so seen not to use .050 or went with the .004 specs

Jeremyd0813 · Dec 30, 2019

Grumpy said:
keep in mind when ordering heads that vortec style heads require a matching vortec style intake
always ask what intakes fit any heads you might order
a couple hours of research reading threads can save you a ton of cash and weeks of wasted effort

http://garage.grumpysperformance.com/index.php?threads/the-new-215cc-vortec-heads.266/#post-75012

http://garage.grumpysperformance.co...c-gen-1-parts-compatibility.13439/#post-69800

http://garage.grumpysperformance.com/index.php?threads/vortec-edelbrock-tpi.11062/#post-49181

http://garage.grumpysperformance.co...-z51l9889-posted-much-of-this.823/#post-39088

http://garage.grumpysperformance.co...o-flow-firsts-tpi-intake-etc.1052/#post-37127

http://garage.grumpysperformance.co...-vortec-heads-and-other-heads.401/#post-34996

http://garage.grumpysperformance.com/index.php?threads/vortec-info.529/#post-27299

http://garage.grumpysperformance.co...-stock-tpi-engine-components.1509/#post-74581

http://garage.grumpysperformance.co...rger-intake-runners-l98-tpi.13785/#post-70716

http://garage.grumpysperformance.com/index.php?threads/ideal-tpi-build.12203/#post-59273

http://garage.grumpysperformance.com/index.php?threads/can-you-get-there-with-tpi.10494/#post-44299

Hi grumpy, hope all is well and definitely. Just reviving my old thread but still have my first intake with the vortec base

Indycars · Dec 30, 2019

Jeremyd0813 said:
Ok for the heads jegs, summit etc refers to them as afr 912 heads (afr sbc eliminater vortec heads) and took a pic of different specs as well just in case u need it for anything.

Any info is appreciated !

I might be able to use it later for another person without starting over.

Indycars · Dec 30, 2019

Jeremyd0813 said:
Also I tried to you that program and downloaded everything but it's off by 1° from my cam spec sheet, but there specs are at .004 or .050 so seen not to use .050 or went with the .004 specs

The advertised duration could be off be a couple degrees, since some rate the seat-to-seat (Advertised Duration)
at different lifts (ie .004 or .006 inches or .....), but it's better than nothing.

Please post your numbers from the Excel spreadsheet. You never know what questions it might bring to light.

Jeremyd0813 · Dec 30, 2019

Indycars said:
The advertised duration could be off be a couple degrees, since some rate the seat-to-seat (Advertised Duration)
at different lifts (ie .004 or .006 inches or .....), but it's better than nothing.

Please post your numbers from the Excel spreadsheet. You never know what questions it might bring to light.

Attached pics of spreedsheet data

Indycars · Dec 31, 2019

Below are your results. I do want to mention that Dynomation does not know how to handle
asymmetrical cam lobes like yours. Please open the PDF report at the bottom and verify the
numbers I used.

You mentioned printing the graph, if you do really want to print to paper, then I can send you
a higher resolution graph.

Jeremyd0813 said:
There correct now, used the Wallace racing calculators and the cam is a custom grind cam that they recommend. And the scr 9.67 and dcr of 9.10

I can't see rows 2, 3, 4 in your photo of the Excel file so I cannot verify all your numbers, but
I get something very different. Also you didn't need to use 2nd tab to calculate your IVC angle
when the cam card gives that to you. Even so, that one degree only changes the SCR/DCR to
8.18/10.75.

I hope you can get 93 octane, if you are like me I can only get 91 octane. My DCR was 8.27 and
I had some problems with detonation until I retarded the cam timing 4°.

.

Jeremyd0813 · Dec 31, 2019

Indycars said:
Below are your results. I do want to mention that Dynomation does not know how to handle
asymmetrical cam lobes like yours. Please open the PDF report at the bottom and verify the
numbers I used.

You mentioned printing the graph, if you do really want to print to paper, then I can send you
a higher resolution graph.

View attachment 13343

I can't see rows 2, 3, 4 in your photo of the Excel file so I cannot verify all your numbers, but
I get something very different. Also you didn't need to use 2nd tab to calculate your IVC angle
when the cam card gives that to you. Even so, that one degree only changes the SCR/DCR to
8.18/10.75.

I hope you can get 93 octane, if you are like me I can only get 91 octane. My DCR was 8.27 and
I had some problems with detonation until I retarded the cam timing 4°.

View attachment 13344
.

Thankyou and I can at certain pumps around me but in your have it as -5 for a dome, mine is +5 (I have flat top pistons with relief) that's probably what did it.

Jeremyd0813 · Dec 31, 2019

Indycars said:
Below are your results. I do want to mention that Dynomation does not know how to handle
asymmetrical cam lobes like yours. Please open the PDF report at the bottom and verify the
numbers I used.

You mentioned printing the graph, if you do really want to print to paper, then I can send you
a higher resolution graph.

View attachment 13343

I can't see rows 2, 3, 4 in your photo of the Excel file so I cannot verify all your numbers, but
I get something very different. Also you didn't need to use 2nd tab to calculate your IVC angle
when the cam card gives that to you. Even so, that one degree only changes the SCR/DCR to
8.18/10.75.

I hope you can get 93 octane, if you are like me I can only get 91 octane. My DCR was 8.27 and
I had some problems with detonation until I retarded the cam timing 4°.

View attachment 13344
.

Row 8 should be +5

Indycars · Dec 31, 2019

Yeah, you are right, that bring your SCR/DCR to 7.38/9.58. That's why I always ask the person
to review my numbers when I do a simulation.

What octane gas are you planning to use?

1986 iron head l98 corvette valve spring question

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