The Inevitable Build Thread

[Grumpy]

"Grumpys" corvette had the cam installed retarded from the common dot to dot instal TDC to strait up, and had aluminum heads, I was running about a 14,7:1fuel/air ratio at idle that progressively got richer as rpms climbed , it ran about 13.5:1 fuel/air ratio over 2500 rpm that dropped to about a 13:1 fuel/air ratio by about 4500 rpm, and had much larger that stock fuel injectors and a much better fuel pump and fuel pressure regulator, add, I used a mildly modified HOLLEY 890-160 distributor and CPU programing
a HUGE oil cooler and a trans fluid cooler, and a huge radiator and I was running premium octane fuel, and a custom ignition advance curve
and I frequently added octane boosters to the tank
so that's not particularly comparable

 

[arlowf]

"Grumpys" corvette had the cam installed retarded from the common dot to dot instal TDC to strait up, and had aluminum heads, I was running about a 14,7:1fuel/air ratio at idle that progressively got richer as rpms climbed , it ran about 13.5:1 fuel/air ratio over 2500 rpm that dropped to about a 13:1 fuel/air ratio by about 4500 rpm, and had much larger that stock fuel injectors and a much better fuel pump and fuel pressure regulator, add, I used a mildly modified HOLLEY 890-160 distributor and CPU programing
a HUGE oil cooler and a trans fluid cooler, and a huge radiator and I was running premium octane fuel, and a custom ignition advance curve
and I frequently added octane boosters to the tank
so that's not particularly comparable

Lol. I like the final line there of "so that's not particularly comparable". Point made and taken.

I'm asking a million questions but I'm also reading constantly. The problem with that is everyone is an expert compared to me, and everytime I am about to pull the trigger on $3,000 in parts, I find out I missed something.
In this case it's DCR. I read that DCR was good between 7.5-8.5 on pump gas, and a static compression of 10.2 was definitely streetable.

Now I'm hearing (and I believe him) that my DCR is going to cause detonation, and SCR is worthless.

I can't get my block ready or to the machine shop until I have my rotating assembly kit so I'm eager to figure this out. I've read like every thread on this forum now (I'm not kidding) and while some of it I don't understand, the bigger issue is a lot of it at face value is contradicting.

I'm fine with it taking a while I just want to make sure everyone knows I am reading the links they throw out, and watching videos, and listening. Not being lazy. If I was lazy I'd just buy a crate engine; it's about the same price. I want to learn and get it right.

 

[Grumpy]

your certainly not alone in having been a bit confused at times,
were ALL ignorant to these factors and how they interact in the beginning,
thats the main reason I built the web site,
to smooth and speed up the process and help you avoid making mistakes
but IF you keep reading links and taking notes, and asking a few questions,
things will eventually become much clearer,
and you'll get a better grasp on all the concepts and how they interact
(compression,
bore to stroke ratios,
rocker ratios,
valve spring load rates,
cam timing,
air flow, through heads, & intake,
and header exhaust scavenging
lubrication,
bearing cooling,
valve train control,
fluid pressures and cooling,
ignition timing, etc.)+
I'm sure if you do a few search's on this web site you'll find lots of threads and sub linked info

btw
youll eventually find dozens of engine builds on the internet, it may take you a few years,
but you'll eventually pick up on the fact ,that the vast majority of those internet engine build's intentionally just skip over or ignore a great many of the assembly processes, like the better valves, roller rockers, valve springs, port work, extensive block machine work, and don't mention they used, upgraded pistons ,rings, oil pan, ETC.
or related costs you'll be incurring, to duplicate the results they claim,
or the whole link is designed to sell some part or brand of parts, and they darn sure won,t point out your options or the associated costs and required machine work related to and mandatory in most cases to build that engine

 

[Indycars]

What's do I need to change about my quench/deck height/pistons to stay "higher compression" but get my DCR down just a little to 7.9-8.0ish? Just go with a bigger dish piston? That seems like that'd be overkill. Increase deck to piston clearance to .015?

Like I said above, I think you will be OK. Especially if you use the suggestions from NewbVetteGuy. If you don't mind having to go back and change the cam timing later if detonation becomes a problem, then absolutely stay with with the dot-to-dot cam installation.

Without a doubt retarding the cam just 2 degrees should eliminate any chance of detonations There are other reasons for wanting to retard the cam timing. It will move the power band up slightly, maybe 100 rpm. Grumpy tends to install his cams 4 degrees retarded, so you would not be doing anything out of the ordinary.

I'm surprised that you have not taken me up on my offer to run some simulations with Dynomation 6? Have you already purchased your Howards camshaft?

 

[arlowf]

Like I said above, I think you will be OK. Especially if you use the suggestions from NewbVetteGuy. If you don't mind having to go back and change the cam timing later if detonation becomes a problem, then absolutely stay with with the dot-to-dot cam installation.

Without a doubt retarding the cam just 2 degrees should eliminate any chance of detonations There are other reasons for wanting to retard the cam timing. It will move the power band up slightly, maybe 100 rpm. Grumpy tends to install his cams 4 degrees retarded, so you would not be doing anything out of the ordinary.

I'm surprised that you have not taken me up on my offer to run some simulations with Dynomation 6? Have you already purchased your Howards camshaft?

I have not purchased the Howard cam because I was on pause trying to understand DCR. I know what "to do" now that you've literally spelled it out for me: retard the cam 2 degrees. Which I'm going to do from the start. I've been watching videos on timing so I at least know what you're talking about.

I'm trying to understand the why; and I think that retarding the cam changes the intake and exhaust timing in such a way that there is a little less max compression in the cylinder because the in/exh valves have slightly more overlap (meaning they are cracked open at the same time). Is that why I'm retarding the cam?

I would absolutely love to take you up on your offer of running the numbers for me I just am aware I'm already taking up a lot of your time. You need a few cam selections from me, and to know that I'm okay with retarding the cam a degree or 2 to make it run better on the street, right?
I'm down to that Howard or Grumpy's cam that he listed above; I like his because it's almost identical except for the lift. But I will be running a 2800 stall, not a 3000; I want zero chance of that "looseness" feeling when driving.
And I'll be purchasing that Sharktooth oil pump and Stewart Stage1 pump like NewbVetteGuy recommended; I'm paranoid about cooling and like overkill when it comes to that. I buy very expensive electric fans and combine them with a 4 core aluminum radiator.
That all "should" help with detonation.

 

[Indycars]

I'm retired, so time is not a factor. Like other's here we get as much from helping as the person getting the help does!!!

Below is what I will need for info before I can can get started with the simulations. I know lots of it is already in this thread, but it helps me to have it ALL in one place. Thanks !

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 Relief Volume: For a piston with valve reliefs or dish, use a (+) positive number.
Deck Height: (Piston to Block Surface)
Head Gasket Bore:
Head Gasket Thickness:
Valve Sizes Intake/Exhaust:
Intake Manifold Type: [Single or Dual Plane]
Manufacture/Model #:
Carburetor Size or EFI (CFM):
Header Tube Diameter: 1-5/8", 1-3/4", 1-7/8", 2.0"
Cam Part Number
Rocker Ratio - Intake/Exhaust:
Cam Installed per Cam Card, or Retarded or Advanced:
Fuel Used: Gasoline (Octane ?), Methanol, Ethanol, E85 .....

 

[Indycars]

I'm trying to understand the why; and I think that retarding the cam changes the intake and exhaust timing in such a way that there is a little less max compression in the cylinder because the in/exh valves have slightly more overlap (meaning they are cracked open at the same time). Is that why I'm retarding the cam?

You are right in that there is less DCR, but not because of less Overlap.

Once the cam is ground the distance between the cam lobes cannot change, therefore the overlap does not change. All the valve opening/closing timing events change by the same amount when retarding the cam and in your case by -2°. The important thing related to detonation or DCR is the IVC is retarded by -2°. So in the case of the Howards 110245-12 cam the IVC changed from 67° ABDC to 69° ABDC. The piston is 2° closer the TDC.

BTW, this cam has 4° Advance ground in. So installing it dot-to-dot, means installing the cam with 4° advance. Retarding the cam 2°, still means installing the cam with 2° advance (4-2=2).

To continue, installing the cam "straight up" or "split overlap" means to install the cam with neither advance or retard. The cam is installed with 0° advance/retard.

Hope this helps !!!


.

 

[Grumpy]

thank you RICK!

 

[Indycars]

thank you RICK!

Not a problem. It one way I have of helping !!!

 

[arlowf]

I'm retired, so time is not a factor. Like other's here we get as much from helping as the person getting the help does!!!

Below is what I will need for info before I can can get started with the simulations. I know lots of it is already in this thread, but it helps me to have it ALL in one place. Thanks !

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 Relief Volume: For a piston with valve reliefs or dish, use a (+) positive number.
Deck Height: (Piston to Block Surface)
Head Gasket Bore:
Head Gasket Thickness:
Valve Sizes Intake/Exhaust:
Intake Manifold Type: [Single or Dual Plane]
Manufacture/Model #:
Carburetor Size or EFI (CFM):
Header Tube Diameter: 1-5/8", 1-3/4", 1-7/8", 2.0"
Cam Part Number
Rocker Ratio - Intake/Exhaust:
Cam Installed per Cam Card, or Retarded or Advanced:
Fuel Used: Gasoline (Octane ?), Methanol, Ethanol, E85 .....

I'll have this to you by tomorrow. This is actually a great checklist to plan the build start to finish.

 

[arlowf]

Rick/IndyCars, here you go:

Bore & Stroke: 4.030 3.75

Displacement: 383 cubic inches

Rod Length: 6 inches

Heads Make/Model with flow numbers: Dart Pro 1 200 Aluminum

https://newdart.wpenginepowered.com/wp-content/uploads/SHP-200-tech-sheet-H12.pdf



Combustion Chamber Size in CC’s: 64cc

Dome Volume: 0

Valve Relief Volume: +5 (Flat Top, with two Valve reliefs, Hypereutectic Aluminum)

https://www.summitracing.com/parts/uem-9909hc-030

Deck Height: (Piston to Block Surface)

Head Gasket Bore: 4.166

Head Gasket Thickness: .039

Decked so piston is .010 in the hole. This puts my total quench at .040; do you think a machine shop should be able to be precise with decking so that my pistons are exactly at .005in the hole instead of .010? I'm guessing not.

Valve Sizes Intake/Exhaust: Exh 1.6, Intake 2.02

Intake Manifold Type: Dual Plane

Manufacture/Model #: Edelbrock Performer RPM

Carburetor Size or EFI (CFM): 800 CFM Edelbrock AVS2; which youtubers claim is more like a 650cfm Holley

Header Tube Diameter: 1-5/8", 3” Collector, 2.5 inch exhaust

Cam Part Number: Howard 110245-12

Rocker Ratio - Intake/Exhaust: 1.6/1.6

Cam Installed Retarded 2 degrees (but cam card says it's 4 advanced; so this works out to 2 Advanced)

Fuel Used: Gasoline, 91 Octane


Edit: on the quench stuff, just know I'm going to be at .038 - .040, by picking the right head gasket. And I'll be around .005-.010 piston to deck clearance. But it's silly to give exact measurements until the machine shop does the decking with my piston. I'm going to ask that they take off as little as possible and keep me as close to .005 in the hole as possible. Dart wants .010 for their heads but that a general guideline.

 

[Indycars]

Some comments before we get started.

- When you order the heads make sure you get them with 7/16" rocker studs.
- When you changed pistons to only 5cc from 12cc you made big change in SCR/DCR, now what?
- You should find a head gasket with a bore closer to 4.030 + .(060 to .080)
- Yes they should be able to deck the block very close to your requirements of .002", but you still verify.

Can we figure the pistons before starting the simulations?

 

[Grumpy]

obviously you have options,
but select the best heads you can afford its almost always the best option

Free Shipping on Orders Over $109 at Summit Racing

Find Parts and Accessories dart shp heads KEYWORD and get Free Shipping on Orders Over $109 at Summit Racing!

www.summitracing.com

a set of those dart heads is almost $1780

youll spend a bit more (about $400 more)on profiler heads but they would easily boost power at least 20-30 hp
VERY MUCH WORTH THE EXTRA COST UP FRONT IN MY OPINION

210cc All American Aluminum 23° SBC Racing Heads, Assembled, Angle Plu

Producer and Seller of aluminum aftermarket cylinder heads, intake manifolds and engine accessories. Specializing in big block chevy ,small block chevy, big block ford and small block ford.

www.profilerperformance.com

195cc SBC Race Cylinder Head

Cylinder Head Specialists

www.airflowresearch.com

as a general rule, on a SBC performance engine build ,
try to select a cylinder head that reaches or exceeds 250 cfm at .500 lift and ideally 280 cfm PLUS at max lift PLUS
or you could get similar performance to the dart heads for several hundred dollars less

195cc SBC Enforcer Cylinder Head

Cylinder Head Specialists

www.airflowresearch.com

if you want good but inexpensive heads, use what RICK used Ive used them on several street performance builds

Brodix Cylinder Heads IK 200​

IK® Series Cylinder Heads/23°

• Standard Valve Cover Pattern • 64 cc / 70 cc Combustion Chambers • Straight Spark Plugs • Ends Milled and Drilled for Accessories • Ductile Iron Valve

brodix.com

Cylinder Heads at Summit Racing

Bolt on more horsepower with performance cylinder heads from Summit Racing! Shop cast iron, aluminum, CNC-ported, CNC-profiled cylinder heads & more.

www.summitracing.com

yeah, inexpensive is a relative term but dirt cheap heads really are not an option if you want decent results

 

[arlowf]

Some comments before we get started.

- When you order the heads make sure you get them with 7/16" rocker studs.
- When you changed pistons to only 5cc from 12cc you made big change in SCR/DCR, now what?
- You should find a head gasket with a bore closer to 4.030 + .(060 to .080)
- Yes they should be able to deck the block very close to your requirements of .002", but you still verify.

Can we figure the pistons before starting the simulations?

Yeah I made the move to flat top because their website claims the 5cc pistons put me around 10.5:1. I've been a victim of 8.8:1 compression before, don't love it. But I can stay with 5cc dished pistons and go to 9.6:1; I just don't want to go any lower than that.
Compression is what's going to make a huge difference in my low end power and I don't want all these fancy parts and then be sitting at 9:1 compression. Dialing in compression is cheap and effective and will have a major impact on my build. 10.0:1 seems to be that perfect spot everyone wants to hit. But i know that's static compression.
Thanks for catching the gasket, I'll fix that. Let me keep shopping; I was focused on the thickness and composite (copper ring).

Noted on the rocker studs.

Grumpy,
I'll look at the AFR aluminum heads. But I saw good videos on dart, I read an article where they barely edged out AFR, and if I keep changing things Rick might kill me

Here are some other pistons I could have them swap into the kit. Just expensive, but that's all fine. All for a stroker engine with 6.0 rods.
The "kit" has an internally balanced crank, for a 1 piece rear main seal, and then they balance all the components in house before shipping.

​

 

[Stuart Wall]

I came here tonight to investigate cylinder hone grit vs. ring material but got caught up in reading this thread. I am a rookie novice as well, and have been trying to soak up all engine building info I can. It started for me in about 2018 when I was researching cam specs. Then I decided that I wanted to understand enough about it to spec my own cam. lol...I have built one engine out of mostly used parts just to learn things so when I spend actual money on it, I wouldnt waste money. Anyway, if you dont mind, I will tag along and watch you guys wrestle thru this one. BTW, Rick, you sent me a DCR calculator and I use it often in different scenarios. I really like it. That one engine has about 1500 miles on it and 8 dragstrip passes last summer. 14.28 @ 99.9 mph with a 2.4 60 ft. It was fun enough I can spit out those #s from memory .

 

[arlowf]

Grumpy,
on your suggestion about different head options, if I were to go with the AFR (remembering my lift is maxed out at 520 and rpms stay sub 5500) I would likely skip AFR and go even (dirt) cheaper to DNA. These are so cheap ($240 a head) I could do a garage port job (tons of videos on youtube; if Rick can die grind every surface of his entire engine I think I can do some heads) OR have a machine shop deck and port them, which is something I'd look at with even AFR's. This a "right out of the box" flow bench comparison, and these number get about 6% better once the heads are cleaned up. Literally the cost of 2 DNA heads is the cost of 1 AFR head, and the funds that leaves for Machine shop magic are substantial.

 

[Grumpy]

obviously you can do anything you chose but going with the least expensive head option REALLY DOOMS the power potential of your engine even if those heads are ported, I doubt the result would be nearly as close as the chart indicates or put differently YOULL ALWAYS REGRET GOING FOR THE CHEAP HEAD OPTION

if you want good but inexpensive heads, use what RICK used

Cylinder Heads at Summit Racing

Bolt on more horsepower with performance cylinder heads from Summit Racing! Shop cast iron, aluminum, CNC-ported, CNC-profiled cylinder heads & more.

www.summitracing.com

yeah, inexpensive is a relative term but dirt cheap heads really are not an option if you want decent results

 

[arlowf]

obviously you can do anything you chose but going with the least expensive head option REALLY DOOMS the power potential of your engine even if those heads are ported, I doubt the result would be nearly as close as the chart indicates or put differently YOULL ALWAYS REGRET GOING FOR THE CHEAP HEAD OPTION

if you want good but inexpensive heads, use what RICK used

Cylinder Heads at Summit Racing

Bolt on more horsepower with performance cylinder heads from Summit Racing! Shop cast iron, aluminum, CNC-ported, CNC-profiled cylinder heads & more.

www.summitracing.com

yeah, inexpensive is a relative term but dirt cheap heads really are not an option if you want decent results

one of the two or three most critical options you will make is selecting the correct cylinders heads and flow rates

The way you responded/stated what you just did tells me the game of cheap with Machine shop labor is one I should avoid. Thanks, i'll stop that right now. AFR it is.

 

[Indycars]

Yeah I made the move to flat top because their website claims the 5cc pistons put me around 10.5:1. I've been a victim of 8.8:1 compression before, don't love it. But I can stay with 5cc dished pistons and go to 9.6:1; I just don't want to go any lower than that.

You didn't believe the calculation that showed your SCR to be 10.24 in post #10 ??? They claim 10.5, but with what chamber size? They don't know your engine specs.

You can go with the 5cc pistons, but you will have to change the combustion chamber size. Your Dart SHP heads also come in a 72cc version. And if needed you might need to mill them to reduce the chamber a few CC's. Below is Dart's milling instruction for your heads.

Milling:
Min. 58cc = .060” (.0065” = 1cc) Flat Mill

Or you can stay with your original plan and use the 12cc dished pistons. Just one comment, forged piston are better able to withstand a more pronounced detonation and for a longer time.

Don't buy anything until after the simulations are complete!!!, You might be surprised at what is learned and the changes that are still to come with the camshaft !!!

In the Excel table below, you will notice the red numbers. If a number from the previous engine changed, then it's in RED. If you have Excel you can do your own calculations, use the link below.

https://garage.grumpysperformance.com/index.php?threads/dynamic-static-comp-ratio-cranking-pressure-calculator.4458/

 

[Indycars]

BTW, Rick, you sent me a DCR calculator and I use it often in different scenarios. I really like it. That one engine has about 1500 miles on it and 8 dragstrip passes last summer. 14.28 @ 99.9 mph with a 2.4 60 ft. It was fun enough I can spit out those #s from memory .

Glad you like calculator!!! I got tired of the online ones, you could only do one engine at a time and then how do you document that setup for comparison later. So that's why I wanted the Excel one that's uploaded here.

Yes, I can still remember my best time from the 1970's, so I understand your memory comment. They didn't have 60 foot times back then.