Thoughts on using this setup on 351 build

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114LSA EFI it was a custom cam for my last blower build, designed to carry the tq curve all the way up to 7k rpm.. I am sure that it wont do that in the 393 but we will see... if it does not perform as expected then next year it will get a new cam.
ok. Are you blowing the 393 as well?
 
really? Yea I know it came in 75mm version too but thought it might be too small. I guess sometimes smaller ain't bad in that regard and I definitely want to try and properly match the combo this time around as opposed to what I did back in 03. I think I'd be better served going with the 75 mm one

A 75MM TB will support some good power. I know Accufab rates their 75mm throttle body @ 924 CFM @ 28". 924 CFM will support 700-800 HP. I'm not saying you wouldn't pick up some additional power at that level with a larger throttle body due to reduced restriction, but 75mm is more than enough for your power goals and won't be a restriction at that level.

Edit, just did a quick calc and it looks like your engine will need ~600-650 CFM to make the desired power output (Spinning to 6000 RPM).
 
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A 75MM TB will support some good power. I know Accufab rates their 75mm throttle body @ 924 CFM @ 28". 924 CFM will support 700-800 HP. I'm not saying you wouldn't pick up some additional power at that level with a larger throttle body due to reduced restriction, but 75mm is more than enough for your power goals and won't be a restriction at that level.

Edit, just did a quick calc and it looks like your engine will need ~600-650 CFM to make the desired power output (Spinning to 6000 RPM).
cool gotcha
 
Sounds like a lot of work for a mild street setup.

75mm is fine but you can get a edlebrock 90mm if you really want.
I'd highly suggest going straight to a aftermarket k-member.
from what Hoytster said in post #45 I think that will be very beneficial for me.

Well I was thinking about doing a 331 and using my tf 170's and performer 2 on it but I may just do that in the 94 cobra. It's either a 331 or 351. I'd rather 400'ish hp hopefully near 450 vs maybe 340ish
 
Bigger than 190's on a less then 390 cubic inch mild street build built primarily for low end torque? Of course a bigger head would have more HP potential, but if his goal is truly a mild torquey street build, I think he would be fine with 190's. Last 351 based motor I had my hands on with TW190's made ~420HP and 470TQ to the tire with a very mild .550 lift cam.

Some things are exagurated. I think the peak torque rpm between a 302 and a 351 would be a few hundred RPM in difference. It's a lot of money and headache to go to a 351 block for a difference that will be hardly noticable.

Kurt
 
Some things are exagurated. I think the peak torque rpm between a 302 and a 351 would be a few hundred RPM in difference. It's a lot of money and headache to go to a 351 block for a difference that will be hardly noticable.

Kurt
When you say bigger what size are you referring to or recommending? The thing is as to what I want as far as manners and driveability I'm not trying to maximize the build as to affect those things. I understand you know if I was trying to get the most out of it and everything like that but I don't want to have I want I don't want to worry about all of those things and then be mad and how the car is driving and bucking Etc.
 
When you say bigger what size are you referring to or recommending? The thing is as to what I want as far as manners and driveability I'm not trying to maximize the build as to affect those things. I understand you know if I was trying to get the most out of it and everything like that but I don't want to have I want I don't want to worry about all of those things and then be mad and how the car is driving and bucking Etc.

I totally get what you are trying to accomplish. A car that is constantly bucking and chugging ends up being a car you never drive. I am full in on building cars that can be enjoyed on a daily basis. I just think going to a 351 block is more academic than practical. If you put the same heads on a 347 with a 114 lobe sep cam, I think it would come out about the same; or at least no noticable difference. There is a mountain of costs and headache saved by using the factory bolt in block. 351 swaps nickel and dime you to death if you want to run a perfect street car. Motor mounts, special headers that don't fit right and scrub on every speed bump, hood clearance, intake pipes that don't fit, oil pans that hang below the K-member, an AC compressor that hits the battery tray or clutch cable, etc, on and on. Not to mention the costs, special link bar lifters, special distributer, special lower intake, etc, all the other things mentioned as merely hassles. This is just my opinion, and I don't think going with a 351 block is a terrible idea. I just think it will need more swear words, and take many more hours and months that you are not driving your car.

Kurt
 
A 75MM TB will support some good power. I know Accufab rates their 75mm throttle body @ 924 CFM @ 28". 924 CFM will support 700-800 HP. I'm not saying you wouldn't pick up some additional power at that level with a larger throttle body due to reduced restriction, but 75mm is more than enough for your power goals and won't be a restriction at that level.

Edit, just did a quick calc and it looks like your engine will need ~600-650 CFM to make the desired power output (Spinning to 6000 RPM).
I know he said horsepower for that setup would peak anywhere from 5 to 5500 maybe 6k. But definitely don't want to go too big of a cam to hurt the drivability and manners desired.
 
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I totally get what you are trying to accomplish. A car that is constantly bucking and chugging ends up being a car you never drive. I am full in on building cars that can be enjoyed on a daily basis. I just think going to a 351 block is more academic than practical. If you put the same heads on a 347 with a 114 lobe sep cam, I think it would come out about the same; or at least no noticable difference. There is a mountain of costs and headache saved by using the factory bolt in block. 351 swaps nickel and dime you to death if you want to run a perfect street car. Motor mounts, special headers that don't fit right and scrub on every speed bump, hood clearance, intake pipes that don't fit, oil pans that hang below the K-member, an AC compressor that hits the battery tray or clutch cable, etc, on and on. Not to mention the costs, special link bar lifters, special distributer, special lower intake, etc, all the other things mentioned as merely hassles. This is just my opinion, and I don't think going with a 351 block is a terrible idea. I just think it will need more swear words, and take many more hours and months that you are not driving your car.

Kurt
9
I understand all of that also and appreciate the insight. Now as for the difference between the 347 to a 385 (after the stroke) just in that difference alone won't it be pretty significant? I get the hassle, ect sure. What about the oil comsumption and the longevity of the 347. My homeboy before he built his 410 built a 347 and he said that thing drunk oil and lasted about 1100 miles and forgot what happened to it. Just over the years never really heard anything good about 347s.

I also know that I have to run fox swap headers, ect. I have a list from a few years ago and you and I even exchanged some emails as well.

Here is Josh Ruppert's stock 351 setup and when he sold the car untuned, it made 368/372 on dyno. When the guy tuned it it made 414/420. Those are pretty good numbers for his setup and mine will be similiar but should net even more since it'll be stroked and i'm assuming and have better pistons:


View: https://www.youtube.com/watch?v=gDLn0VoMdnU&t=2s
 
9
I understand all of that also and appreciate the insight. Now as for the difference between the 347 to a 385 (after the stroke) just in that difference alone won't it be pretty significant? I get the hassle, ect sure. What about the oil comsumption and the longevity of the 347. My homeboy before he built his 410 built a 347 and he said that thing drunk oil and lasted about 1100 miles and forgot what happened to it. Just over the years never really heard anything good about 347s.

I also know that I have to run fox swap headers, ect. I have a list from a few years ago and you and I even exchanged some emails as well.

Here is Josh Ruppert's stock 351 setup and when he sold the car untuned, it made 368/372 on dyno. When the guy tuned it it made 414/420. Those are pretty good numbers for his setup and mine will be similiar but should net even more since it'll be stroked and i'm assuming and have better pistons:


View: https://www.youtube.com/watch?v=gDLn0VoMdnU&t=2s



9
I understand all of that also and appreciate the insight. Now as for the difference between the 347 to a 385 (after the stroke) just in that difference alone won't it be pretty significant? I get the hassle, ect sure. What about the oil comsumption and the longevity of the 347. My homeboy before he built his 410 built a 347 and he said that thing drunk oil and lasted about 1100 miles and forgot what happened to it. Just over the years never really heard anything good about 347s.

I also know that I have to run fox swap headers, ect. I have a list from a few years ago and you and I even exchanged some emails as well.

Here is Josh Ruppert's stock 351 setup and when he sold the car untuned, it made 368/372 on dyno. When the guy tuned it it made 414/420. Those are pretty good numbers for his setup and mine will be similiar but should net even more since it'll be stroked and i'm assuming and have better pistons:


View: https://www.youtube.com/watch?v=gDLn0VoMdnU&t=2s


I think your friend suffered from luck of the draw. His 347 wasn't put together right, or wasn't machined right, or something just went wrong. Sometimes that just happens. I was on lucky side, my last 347 went 85,000 miles with almost 500hp to the tire. After all that, it was the clutch that killed the engine; nothing wrong with the combo itself. There is a lot of misinformation about 347s. The oil consumption issues come from budget kits running the factory 5.08" connecting rod instead of a 5.4" rod. If you run a 5.4" rod, the stroke/rod ratio is no more aggressive than the old 400cid small blocks GM put in trucks back in the day.

I think that the odds are just about equal in almost every direction. You could spend a huge amount of money on 351 swap parts, and end up being worse off. I would take quality over quantity (displacement) every day. A good engine from Woody at Ford Strokers, or another reputable competitor, is going to be worth the money in the end.

I watched the video you attached. I am not sure if that car has a really aggressive cam, or is not tuned well at all.

Kurt
 
I think your friend suffered from luck of the draw. His 347 wasn't put together right, or wasn't machined right, or something just went wrong. Sometimes that just happens. I was on lucky side, my last 347 went 85,000 miles with almost 500hp to the tire. After all that, it was the clutch that killed the engine; nothing wrong with the combo itself. There is a lot of misinformation about 347s. The oil consumption issues come from budget kits running the factory 5.08" connecting rod instead of a 5.4" rod. If you run a 5.4" rod, the stroke/rod ratio is no more aggressive than the old 400cid small blocks GM put in trucks back in the day.

I think that the odds are just about equal in almost every direction. You could spend a huge amount of money on 351 swap parts, and end up being worse off. I would take quality over quantity (displacement) every day. A good engine from Woody at Ford Strokers, or another reputable competitor, is going to be worth the money in the end.

I watched the video you attached. I am not sure if that car has a really aggressive cam, or is not tuned well at all.

Kurt
It's not tuned in that video
 
Kurt is right on with what he said above IMO. A 351 based build will definitely have more issues to deal with then sticking with the stock block as well as the potential of a properly built 347. I'm not one to steer people in a different direction though so I just try to give suggestions based on what direction they want to go.

There's benefits to the additional cubes and resulting torque curve and drivability on a mild built and stroked 351 for street use IMO, but I think the point that Kurt is making is the benefits might outweigh the additional work it will take to put a 351 in your vehicle with your power goals. I wouldn't expect the combination you are talking about to make more then 420-430HP to the tire which is achievable with a 347. It won't have the average torque curve of the stroked 351 build but peak torque and HP could be about the same.

Personally, if I were doing another stock block based 351 swap it would be a 408 based build with a goal of 500+HP to the tire since if I'm going through the hassle, it's going to make some power. But I also get the desire for a very strong low to mid-range torque engine for the street.
 
Kurt is right on with what he said above IMO. A 351 based build will definitely have more issues to deal with then sticking with the stock block as well as the potential of a properly built 347. I'm not one to steer people in a different direction though so I just try to give suggestions based on what direction they want to go.

There's benefits to the additional cubes and resulting torque curve and drivability on a mild built and stroked 351 for street use IMO, but I think the point that Kurt is making is the benefits might outweigh the additional work it will take to put a 351 in your vehicle with your power goals. I wouldn't expect the combination you are talking about to make more then 420-430HP to the tire which is achievable with a 347. It won't have the average torque curve of the stroked 351 build but peak torque and HP could be about the same.

Personally, if I were doing another stock block based 351 swap it would be a 408 based build with a goal of 500+HP to the tire since if I'm going through the hassle, it's going to make some power. But I also get the desire for a very strong low to mid-range torque engine for the street.
i appreciate you guys insight and taking the time that means a lot. Some folks don't care to help others these days. I'll have a conversation with him about the 347 and what his ideas would be given what I relayed to him what I'm trying to achieve. If it would be more or have more brunt on the top where it won't spend most of it's time then that's probably not for me. I don't mind taking time with the build and installation ect just as long as it's right at the end. I just bought a Terminator in July with around 500 rwhp and haven't really gotten to drive it much since we started working OT around the clock in Sep and will the month of Oct as well. Also have a 94 cobra that I might build after the 95. I wanted to do a 331 for the cobra first then I dilly dallied with rather to do a 331 in the 95 and the 351 in the cobra. I wanted to go up in hp vs down and wanted to get the Terminator last but I couldn't hold out any longer lol.

My homeboy did a 410 and it's a monster but he built it to race more so at the time and it's drivability aint great at low rpms. He now isn't into racing as much and really just got the car running I think a few yrs ago but has been down some with transmission issues and few other things. Now that he has it right he said he really doesn't plan to race. The builder and I talked about doing a 400 c.i. via big bore and getting a dart block and 3.750 crank. I was all in for that idea over the past few years of us talking about it but realized I don't need to spend that much on a block if I'm not going to race really, track or anything. I'll play around on the street as I choose. He said with a stock block he wouldn't advise a 4 " stroke because it would definitely be what my buddy has in that regard and go against what I aim to achieve.
 
Lot's of good points.

You can build a plenty nice 331 or 347 for the cost of all the extra must haves that come along with a 351w swap. The main reason IMO to go with the 351 is you are planning to get into 302 block splitting HP levels. If you aren't than IMO it is not worth all the trouble.

This is from someone who is currently putting a 408 in my 94, but I am building it to be a 7.0 bracket car not a street cruiser so much..
 
Lot's of good points.

You can build a plenty nice 331 or 347 for the cost of all the extra must haves that come along with a 351w swap. The main reason IMO to go with the 351 is you are planning to get into 302 block splitting HP levels. If you aren't than IMO it is not worth all the trouble.

This is from someone who is currently putting a 408 in my 94, but I am building it to be a 7.0 bracket car not a street cruiser so much..
what are the 302 block splitting hp numbers? 400 ish right?