New TFS top end build article
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A small carb is not "better" because it is small.
A large carb can work as well as a small carb.
The engine can only use X amount of air based on the displacement/intake/cam/compression/heads/exhaust.
A 950 cfm carb can be jetted/tuned to work just as good as a 500 cfm carb.
Just because it has the capability to flow 950 cfm does not mean it will flow 950 cfm on an engine.
If the engine does not need it, the carb will not flow it. Jet the carb (adj air bleeds ect) for the air flow demand and it will work just fine with no bog or lean/rich concerns.
But one thing is certain, it the engine can use more air than the carb can provide that is on it, it will always make more power with a larger carb.
If the engine has more carb than it needs, if tuned right, it will not cost the engine in power/driveability/mileage at all.
Same with EFI.
Put a 90mm throttle body on a stock 5.0 and it will work just fine, even though it could flow over 1,350 cfm on the right engine.
Most modern EFI engines have throttle bodies that can flow a lot more air than the engine could possibly use. You can not go to large, but you can go to small.
I am going to respectfully disagree with you... Yes you can jet them differently but the carb is still capable of MORE air and the engine will lose some low end torque because of that, which is what gets you from street light to street light...
The engine can not draw in more air just because the carb is bigger. It is impossible.
If the engine can only use 600 cfm, it does not matter if the carb is 950 cfm.
It will only flow 600 cfm. Period.
You can not change physics.
Jet/tune the 950 cfm carb for 600 cfm of air flow and it will run perfectly.
The engine will never use the extra 350 cfm of capability.
A carb booster works based on the pressure drop of air flow across it.
If the boosters sees 600 cfm of air, it will only draw in enough fuel (if tuned properly) for 600 cfm, despite being capable of flowing more.
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Not according to this article.. Again my concern is street driving characteristics mainly poor response and sluggishness.
Do you realize that in the 'scientific world of the internal combustion engine ' you two are say'n the same thing.
This is what is in my motorAlso, Morel make a high lift high rpm hydraulic lifter but those mofos are north of a grand.
Morel HI-RPM Hydraulic Roller Link Bar Lifters - SBF
Morel 5879 HI-RPM Hydraulic Roller Link Bar Lifters Small Block Fordflowtechinduction.com
Guys, I'm getting the bug...
I've been talking to TMOSS (or MMOSS) all day, in between working on the car. I really think we can do this build better. The Systemax seems to be a beautiful fit, but Tom/Matt has me convinced we can do a max effort Edelbrock RPM I that will flow upwards of 300CFM, while the 11Rs flow 266CFM at .500 lift (over 270 at .600). I'm thinking, maybe solid roller? As to the cam, I'm likely to pull out my old FTI cam specs for an AFR 165 build and rerun them, and/or get back in touch with him to do another custom. The cam in the article had a lot less lift, a bit less duration, and the same LSA. That's gotta be worth a little power. The disadvantage I would have is the stock 200k mi shortblock and prolly a little less compression Can anyone tell me what 53 CC head with a .040 gasket gets me on an otherwise stock shortblock?
I'd like to see peak power at less than 6k and rev it out to a 6.5k shift point, which is the most I wanna spin a stock lower.
The goal would be 350 rwhp na.
It looks like the heads would run me ~$2,500. The intake is going to be $800-$1k + Tom's work. The cam will be a few hundred, and figure a few hundred more for incidentals. Then, I'll get $700-1k back out of the GT40 intake. There's a set of GT40Xs listed on ebay for $1,750?!!! Can I get $1,500+ for these heads? Then, maybe $100-150 for the E-csm. So, the difference of a little over $2k for 70-80 rwhp? Uh... yeah... much better deal than the nitrous I have to keep purchasing, plus 350 and a 150-shot is about the perfect stock shortblock combo.
Gonna make it happen, boys. This is going to be the tribute to my first build. It was a ~320rwhp build and that was in 2001. I think we can safely eclipse that now. Let project It's-not-2000-anymore begin. In the words of the immortal Zohan, "So I am here. So let's go!"
View: https://youtu.be/vwSuYWzlwro?si=FhFQq1mzCj5Svu8D
I've been talking to TMOSS (or MMOSS) all day, in between working on the car. I really think we can do this build better. The Systemax seems to be a beautiful fit, but Tom/Matt has me convinced we can do a max effort Edelbrock RPM I that will flow upwards of 300CFM, while the 11Rs flow 266CFM at .500 lift (over 270 at .600). I'm thinking, maybe solid roller? As to the cam, I'm likely to pull out my old FTI cam specs for an AFR 165 build and rerun them, and/or get back in touch with him to do another custom. The cam in the article had a lot less lift, a bit less duration, and the same LSA. That's gotta be worth a little power. The disadvantage I would have is the stock 200k mi shortblock and prolly a little less compression Can anyone tell me what 53 CC head with a .040 gasket gets me on an otherwise stock shortblock?
I'd like to see peak power at less than 6k and rev it out to a 6.5k shift point, which is the most I wanna spin a stock lower.
The goal would be 350 rwhp na.
It looks like the heads would run me ~$2,500. The intake is going to be $800-$1k + Tom's work. The cam will be a few hundred, and figure a few hundred more for incidentals. Then, I'll get $700-1k back out of the GT40 intake. There's a set of GT40Xs listed on ebay for $1,750?!!! Can I get $1,500+ for these heads? Then, maybe $100-150 for the E-csm. So, the difference of a little over $2k for 70-80 rwhp? Uh... yeah... much better deal than the nitrous I have to keep purchasing, plus 350 and a 150-shot is about the perfect stock shortblock combo.
Gonna make it happen, boys. This is going to be the tribute to my first build. It was a ~320rwhp build and that was in 2001. I think we can safely eclipse that now. Let project It's-not-2000-anymore begin. In the words of the immortal Zohan, "So I am here. So let's go!"
View: https://youtu.be/vwSuYWzlwro?si=FhFQq1mzCj5Svu8D
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I am going to say the CR will be right around 10.6:1. Assumptions are as follows:
Pistons are down in the hole 0.01" - random searches all came to this number. Could be a touch less or a touch more but this is the average
Reliefs on the stock piston is 5.3cc found this in post #5 in this thread - https://stangnet.com/mustang-forums...valve-relief-cc-size-on-stock-pistons.743243/
Used this calculator - https://www.summitracing.com/newsandevents/calcsandtools/compression-calculator
Pistons are down in the hole 0.01" - random searches all came to this number. Could be a touch less or a touch more but this is the average
Reliefs on the stock piston is 5.3cc found this in post #5 in this thread - https://stangnet.com/mustang-forums...valve-relief-cc-size-on-stock-pistons.743243/
Used this calculator - https://www.summitracing.com/newsandevents/calcsandtools/compression-calculator
Dayumn... Higher than I expected. Should be great for pump gas! Wouldn't wanna go too much higher.
Back in the day a cheap performance gain was using lighter springs in the distributor advance...
I tried that with my Dodge after I got it running and it did NOT like it one bit.... I blame todays modern gas....
I reinstalled the heavier springs and all was good again...
I tried that with my Dodge after I got it running and it did NOT like it one bit.... I blame todays modern gas....
I reinstalled the heavier springs and all was good again...
I was looking at the video a couple of times trying to figure out what the difference in specs was between the solid cam and the hydralic before realizing that they literally just dropped in new solid lifters on the same cam. The fact they picked up 9hp up top is awesome, and IMO doesn't begin to address what's most valuable. With solid, I presume a cam can get a lot more aggressive with ramp rates and lift. So, would be cool to see an expert select cams with similar manners for a given combo and see what they get out of it.
The 331 in my Coupe is 11:1 and zero issues on 91 octane (Oklahoma’s super unleaded). Aluminum heads really help with the higher compression ratios.
That 9 HP can be attributed to how tight the valve train timing events become once you remove the "slop" provided by hydraulic lifters.
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