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Old 01-14-2022, 04:45 PM
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Default Am I overbuilding my engine?

Just want to make sure I'm not overdoing it with this motor. It's going in a 70 TA 4spd 3.31 rear. It's for street use but only recreational, not a daily driver. What I want out of the project is a more stout motor (bottom end and valvetrain) and more power. I'm not looking for maximum power, just more than stock. The parts I have selected (with advice from Butler and my builder) are going to put me around 500 hp and 550 tq (I think). Is that gonna be too much for my use? Traction problems, or worse yest breaking driveline parts?

70 WS code block
Scat forged crank 4.25 stroke
Eagle H beam 6.8 rods
E-brock 87 cc heads
JE pistons
10:1 CR
Comp Cams XR288HR cam (236/242 @ .050, 520/540 lift, 110 LSA).
1.5 rockers
Howards Cams (Morels) lifters
Stock intake and Q-jet
RAIII exhaust manifolds

If I went with a stock stroke that would bring me down about 50-60 hp right there. Then with less CID, I could also do a little less cam and still get the lopey idle I want. What do you think??

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70 TA, 467 cid IAII, Edelbrock D-port heads, 9.94:1, Butler HR 236/242 @ .050, 520/540 lift, 112 LSA, Ray Klemm calibrated Q-jet, TKX (2.87 1st/.81 OD), 3.31 rear

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Old 01-14-2022, 04:55 PM
JLMounce JLMounce is offline
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Personally, I think the cam choice is wrong. The RAIII manifolds will like a wider LSA. I'd also ditch the Morels for the Johnson roller lifters, as well as going with at least a 1.6 rocker. I'd want to be closer to .6" lift.

If you're running a basic 255/60/15 tire deal from BFG, Cooper etc. traction will of course be a problem. Run more modern tires or drag radials and it should be alright. Is it "too much" only you can really decide on that. It's a stout bottom end that will give you room to grow, should you choose, and not have to worry about.

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Old 01-14-2022, 04:56 PM
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Should be good to go. Though you are approaching driveline parts breaking territory. Depends on how you drive.

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Old 01-14-2022, 05:40 PM
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Looks pretty good to me and extremely close to what I did. I have 3.08 rear gears and a slightly smaller cam. Could be bigger cam with the cubic inches. Does not cost much more to not worry and have fun when you desire.
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Old 01-14-2022, 06:12 PM
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No such thing as making a engine too stout. Its your money, spent it how you like.

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Old 01-14-2022, 06:20 PM
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If you drive it hard with decent traction your Muncie will be on borrowed time. That trans would like a warmed up 400 much better but run it on regular street radials and you should be ok.
You should have an easy 550Tq/500Hp with your proposed engine.

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Old 01-14-2022, 06:25 PM
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Hell, I’d simply use a hydraulic flat tappet cam in that setup…. Be plenty good for your application. Even though I run a roller in my setup, I’m not generally a fan of them.

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Old 01-14-2022, 06:35 PM
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Quote:
Originally Posted by JLMounce View Post
Personally, I think the cam choice is wrong. The RAIII manifolds will like a wider LSA. I'd also ditch the Morels for the Johnson roller lifters, as well as going with at least a 1.6 rocker. I'd want to be closer to .6" lift.

If you're running a basic 255/60/15 tire deal from BFG, Cooper etc. traction will of course be a problem. Run more modern tires or drag radials and it should be alright. Is it "too much" only you can really decide on that. It's a stout bottom end that will give you room to grow, should you choose, and not have to worry about.
Thanks. Why the Johnsons over the Morels? I thought about the 1.65 rockers but I'm trying to tone it down a bit because I'm not really looking to extract every last bit out of it. Is there any other reason for more lift or just more power?

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70 TA, 467 cid IAII, Edelbrock D-port heads, 9.94:1, Butler HR 236/242 @ .050, 520/540 lift, 112 LSA, Ray Klemm calibrated Q-jet, TKX (2.87 1st/.81 OD), 3.31 rear

https://youtube.com/shorts/gG15nb4FWeo?feature=share
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Old 01-14-2022, 06:40 PM
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Quote:
Originally Posted by TCSGTO View Post
If you drive it hard with decent traction your Muncie will be on borrowed time. That trans would like a warmed up 400 much better but run it on regular street radials and you should be ok.
You should have an easy 550Tq/500Hp with your proposed engine.
I'm not planning on driving it super hard, although I do want to feel it. I was hoping what you mentioned may be true, that my street tires may help preserve my driveline.

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https://youtube.com/shorts/gG15nb4FWeo?feature=share
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Old 01-14-2022, 06:57 PM
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Quote:
Originally Posted by jhein View Post
Thanks. Why the Johnsons over the Morels? I thought about the 1.65 rockers but I'm trying to tone it down a bit because I'm not really looking to extract every last bit out of it. Is there any other reason for more lift or just more power?
I have Morels in my engine. While I have not had reliability issues with them, they're noisy, especially warm. The tolerances on them are all over the place so it's kind of a crap-shoot on if you get quite lifters or ones that clatter.

You certainly don't have to run higher ratio rockers, but the combination would benefit from them. If the valvetrain hasn't already been purchased and setup, the costs are nominally the same. There's little if any cost increase.

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Old 01-14-2022, 07:13 PM
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My 2 cents wonders about the stock manifold, Q- Jet carb, and maybe the R/A 3 manifolds. Your engine wants all the help it can get to breathe. Your block, selected engine internals, and heads are makings of a stout base, There are much better intake manifolds, carbs, and headers out there than those stock part's, and cam choice needs to be matched to whatever these selections are. For example, Tuning A Q-Jet for big power is a chore, and needs spot on jetting and adjustment. I gave up on mine, went to a Holly/Demon, and what a difference.. And 3:31 is the minimum gear for your combo, great for overall cruising, but the next one or two steps steeper takes more advantage of the HP/TQ curves your motor will make. Maybe the Butler boys know best?

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Old 01-14-2022, 07:28 PM
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Quote:
Originally Posted by JLMounce View Post
I have Morels in my engine. While I have not had reliability issues with them, they're noisy, especially warm. The tolerances on them are all over the place so it's kind of a crap-shoot on if you get quite lifters or ones that clatter.

You certainly don't have to run higher ratio rockers, but the combination would benefit from them. If the valvetrain hasn't already been purchased and setup, the costs are nominally the same. There's little if any cost increase.
When did you purchase your Morels? They made some changes to them dimensionally and the oil hole location in 2021. I wonder if that will make a difference? The set I have was made 10/2021

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https://youtube.com/shorts/gG15nb4FWeo?feature=share
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Old 01-14-2022, 07:31 PM
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Quote:
Originally Posted by Dragncar View Post
No such thing as making a engine too stout. Its your money, spent it how you like.
Thanks. Yes, I should have clarified. I'm not worried about making it too stout, just maybe too much power, driveability problems, etc.

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Old 01-14-2022, 07:34 PM
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I would want no part of a 10:1 engine unless I only trailer it to the track. That fuel will only get more expensive.

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Old 01-14-2022, 07:38 PM
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Quote:
Originally Posted by Hesster1977 View Post
My 2 cents wonders about the stock manifold, Q- Jet carb, and maybe the R/A 3 manifolds. Your engine wants all the help it can get to breathe. Your block, selected engine internals, and heads are makings of a stout base, There are much better intake manifolds, carbs, and headers out there than those stock part's, and cam choice needs to be matched to whatever these selections are. For example, Tuning A Q-Jet for big power is a chore, and needs spot on jetting and adjustment. I gave up on mine, went to a Holly/Demon, and what a difference.. And 3:31 is the minimum gear for your combo, great for overall cruising, but the next one or two steps steeper takes more advantage of the HP/TQ curves your motor will make. Maybe the Butler boys know best?
Yeah, I thought about those parts too. I was worried that if Igo aluminum heads, intake and headers I may lighten up the front enough so it sits too high, I really don't like that. Maybe it's not enough to matter, don't know??

I realize I will likely sacrifice some power with the stock intake, carb and exhaust manifolds but I can live with that if it helps the engine look more stock and keeps the proper stance.

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70 TA, 467 cid IAII, Edelbrock D-port heads, 9.94:1, Butler HR 236/242 @ .050, 520/540 lift, 112 LSA, Ray Klemm calibrated Q-jet, TKX (2.87 1st/.81 OD), 3.31 rear

https://youtube.com/shorts/gG15nb4FWeo?feature=share
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Old 01-14-2022, 07:40 PM
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I would want no part of a 10:1 engine unless I only trailer it to the track. That fuel will only get more expensive.
Even with the AL heads?

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Old 01-14-2022, 07:42 PM
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When did you purchase your Morels? They made some changes to them dimensionally and the oil hole location in 2021. I wonder if that will make a difference? The set I have was made 10/2021
They went into the engine in 2015. Maybe the changes will help but I believe the issues with these lifters are more due to machining tolerance and qc than to oiling position.

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Old 01-14-2022, 07:44 PM
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I would want no part of a 10:1 engine unless I only trailer it to the track. That fuel will only get more expensive.
10:1 on an aluminum head with modern combustion chambers is pretty soft. He’d likely be able to run 87 in it if he wanted.

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Old 01-14-2022, 07:47 PM
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I get that concern. Although I run Coil overs that allow ride height adjustment, before that iI simply cut a coil off of the front springs. Stance is everything, but so is a balanced power approach.

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Old 01-15-2022, 12:04 AM
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10:1 on an aluminum head with modern combustion chambers is pretty soft. He’d likely be able to run 87 in it if he wanted.
Not with the cam choice, and while he "may", He also might be retarding the timing some too.
10:1 is NOT needed for over 450 ft lbs of Torque, and THATS what moves you.
Have seen many of these type builds built to impress others and the lack of vacuum makes the brakes kinda "iffy"
Please yourself. Can you go get ice cream comfortably?
Forged Pistons are HARD on the block...... Do you want a good running and long reliable engine?

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