I had some friends and others ask me about why use averages and some of my thoughts around my build.....I had a good friend who was an Nmra true street racer back in the day in south carolina....he is the one who taught me about Powerband averages and how to improve 1/4 mile times and how to plot a suspension and a multitude of other little things from power to weight ratio.. to setting shift points using the power curves..and matching gearing...etc...just sharing what I learned on what I have tested, what works, and potential based on improvement ideas and methods...
400HP 2V N/A....Going back to my roots....
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Did some more analysis of the graphs between the 281 with ported tfs heads and 323 with stock tfs heads...peak power band was extended by 500 to 1000 rpms higher with the ported heads and increased power from 6000 to 6750 considerably....by 30 to 50hp....a true test will be done once the engine is built and I can do a comparison of both...basically... the TFS heads really wake up after a port job....
I did one more overlay with the ported PIs and the 323 vs 281 addind in the ported PI heads and these had identical hp and tq curves with the stroker...peak power on both were around 5650 to 5850....and noth lost considerable power and tq beyond 6250 rpms.....where as the ported TFS heads really shined....with a more stable valve train and spinning past 7000rpms...ported heads would be worth more than 100hp/tq...
Since the stock TFS heads bench airflow peaked at .570 lift and lost flow at .600 it couldnt fully take the .575 lift cam completely....the ported were tested to .600 lift and kept flowing so the power curve ended up the same as the ported PIs......dont get me wrong...the stock tfs heads had much better flows at all lifts and increases power over the Ported PIs but limited the power of the stroker completely...
I did one more overlay with the ported PIs and the 323 vs 281 addind in the ported PI heads and these had identical hp and tq curves with the stroker...peak power on both were around 5650 to 5850....and noth lost considerable power and tq beyond 6250 rpms.....where as the ported TFS heads really shined....with a more stable valve train and spinning past 7000rpms...ported heads would be worth more than 100hp/tq...
Since the stock TFS heads bench airflow peaked at .570 lift and lost flow at .600 it couldnt fully take the .575 lift cam completely....the ported were tested to .600 lift and kept flowing so the power curve ended up the same as the ported PIs......dont get me wrong...the stock tfs heads had much better flows at all lifts and increases power over the Ported PIs but limited the power of the stroker completely...
So looking at he flow comparison across throughout most of the lifts were 20 cfm increas at almost all lifts with a peak flow of 27cfm....ported was 263cfm at .600 lift compared to 236 from the stock TFS heads...and tq was about 25 to 30cfm hige average ported compared to stock TVs heads....with peak of 34 more cfm at .600 lift with 214 vs 180 stock.....
I believe this really limited the stroker from 5000rpm out to 7500 as the heads could not meet the demand for airflow for the cams.....basically...I bet the car felt flat at higher rpms.....but had the same curves as ported PIs....
You could tell as power was 50 to 60 hp higher in the 4k to 5k power band over my set up but was only 30 to 15 hp higher from 6600 to 6750 rpms...and was gradually dropping off past 5000 rpms.....just some more thoughts for those interested....really has me excited for this build to see what is capable...
I believe this really limited the stroker from 5000rpm out to 7500 as the heads could not meet the demand for airflow for the cams.....basically...I bet the car felt flat at higher rpms.....but had the same curves as ported PIs....
You could tell as power was 50 to 60 hp higher in the 4k to 5k power band over my set up but was only 30 to 15 hp higher from 6600 to 6750 rpms...and was gradually dropping off past 5000 rpms.....just some more thoughts for those interested....really has me excited for this build to see what is capable...
Considering the PI cams were limited with exhast timing off by 10deg I feel the ported heads will gain similarly compared to the PI heads over the stroker combo with stock TFS heads....meaning 10 to 15hp from 4000to 5250 and 15 to 20 from 5k to 6250 and 35 to 50hp to 5750....
Speculation at this point but with correct head flow at .600 lift and exhaust timing it would suggest this...
Speculation at this point but with correct head flow at .600 lift and exhaust timing it would suggest this...
So I found this cool chart that shows 60ft in coralation to 0 to 60mph times...was comparing average hp to improvement to 60ft times at the tack and how much the 0 to 60mph was as well....
With a plotted suspension using 410 gears and MT Drag Radial on 17x9 rims I was cutting 1.67 to 1.69 60ft...which coralated to 0 to 60mph in 3.2 to 3.3 seconds...that was with 281 with ported PI setup....12.20s in 1/4 @111mph
Switching to the ported TFS heads I was running 1.55 to 1.56 60fts consistently which equates to 2.5 to 2.6 seconds for 0 to 60 times....11.65 @116 1/4 times
That was with the average hp jump from 300 to 321 hp/tq gains or 21 average gain....peaks were 336 to 355 increase and 50 to 60 more hp/tq at 6750..
To get under 2 sec 0 to 60 times a 1.45 to 1.46 60ft range.....looks like the stroker should add another 44 to 55hp/tq average gain.....possibly getting under 2 seconds for 0 to 60mph times..
Just some ideas on how much improvement can be made but may need to see how the current suspension plotting holds with hp levels...
With a plotted suspension using 410 gears and MT Drag Radial on 17x9 rims I was cutting 1.67 to 1.69 60ft...which coralated to 0 to 60mph in 3.2 to 3.3 seconds...that was with 281 with ported PI setup....12.20s in 1/4 @111mph
Switching to the ported TFS heads I was running 1.55 to 1.56 60fts consistently which equates to 2.5 to 2.6 seconds for 0 to 60 times....11.65 @116 1/4 times
That was with the average hp jump from 300 to 321 hp/tq gains or 21 average gain....peaks were 336 to 355 increase and 50 to 60 more hp/tq at 6750..
To get under 2 sec 0 to 60 times a 1.45 to 1.46 60ft range.....looks like the stroker should add another 44 to 55hp/tq average gain.....possibly getting under 2 seconds for 0 to 60mph times..
Just some ideas on how much improvement can be made but may need to see how the current suspension plotting holds with hp levels...
So I did one final plot comparison of ported PIs, ported TFS heads on a 281 compared to stock TFS heads on a 5.3 stroker....
There are 3 simple ways to get more hp up top which are....bigger cams and or lift profiles....which will shift the power curve up and increase trap speeds and hp...ported heads which will increase hp and tq throughout the power band....or intakes like short runners that will trade off huge power in higher rpms but trade off tq loss as well...having a balanced setup is the key to unlock full potential where the heads, engine, and cam profiles are aligned or matched...
Here are the results...
There are 3 simple ways to get more hp up top which are....bigger cams and or lift profiles....which will shift the power curve up and increase trap speeds and hp...ported heads which will increase hp and tq throughout the power band....or intakes like short runners that will trade off huge power in higher rpms but trade off tq loss as well...having a balanced setup is the key to unlock full potential where the heads, engine, and cam profiles are aligned or matched...
Here are the results...
Attachments
Notice how the power and tq curves are much broader with the stroker with TFS heads vs the ported PIs but the curves more aligned....this is more about intake and how it dictates the power and tq curves...
Also, the power and tq from low to mid were much broader but narrowed out past 5k to 6750....I belive this has more to do with cam profile as an increase of 42 cubic inches needs to breath better on this combo....
Compared to the middle graph where the ported TFS heads flowed better throughout and much more on top end...this shows the potential with a better cam profile needed to support the intake and top end for the stroker.....I belive the sweet spot for the PI intake is 6100 rpms or the profile for cams and intake to achieve this...this will keep perfect drivability down low and maximize the curve throughout...
With the ported heads and a slightly larger cam this could net another 15 t 20hp from 5k and 50 to 70 hp at 6750....just some more thoughts based on findings and observations....
With a ported TFS R 195 heads with bigger lifts the potential for another 25 to 40 hp and tq could be achieved over the ported 185s...
Also, the power and tq from low to mid were much broader but narrowed out past 5k to 6750....I belive this has more to do with cam profile as an increase of 42 cubic inches needs to breath better on this combo....
Compared to the middle graph where the ported TFS heads flowed better throughout and much more on top end...this shows the potential with a better cam profile needed to support the intake and top end for the stroker.....I belive the sweet spot for the PI intake is 6100 rpms or the profile for cams and intake to achieve this...this will keep perfect drivability down low and maximize the curve throughout...
With the ported heads and a slightly larger cam this could net another 15 t 20hp from 5k and 50 to 70 hp at 6750....just some more thoughts based on findings and observations....
With a ported TFS R 195 heads with bigger lifts the potential for another 25 to 40 hp and tq could be achieved over the ported 185s...
Another question to ask is...do TFS Heads flow more on a larger bore....I read in some cases it could. Depending on heads and bore size changes...if the TFS heads are shrouded by the 281 bore then what if any increase can ocure... I will have to test this when the time comes but airflow increases would have an effect on power and cam selection as well.....I will search to see what I can dig up...
So I did some reviews from bench flows and head cfm increases when changing bore sizes....here is what I found...
Yes, flow can increase when valves are shrouded....probably not by a whole lot but can vary by a few cfm like 4 to 5 or upto 10 to 15 cfm depending on how much restriction there was...
If you have an engine that has a larger bore already where the heads already meet there full potential and put the heads on an even larger bore then no gains could be had...it depends if the heads are restricted at all...
Yes, flow can increase when valves are shrouded....probably not by a whole lot but can vary by a few cfm like 4 to 5 or upto 10 to 15 cfm depending on how much restriction there was...
If you have an engine that has a larger bore already where the heads already meet there full potential and put the heads on an even larger bore then no gains could be had...it depends if the heads are restricted at all...
If 5 to 10 cfm can be gained, this could actually increase power potential by 10 to 30hp for power potential gains for cylinder heads....especially if low and mid range flow numbers increases...I posted on this in another thread for the math on head flow potential power numbers and actually matches real world results.....just some more info sharing on my findings as these can impact any engine type or build....
So I just ran the math on rwhp gains from increase in head flows for example...
My current ported heads with 214 exhaust flow and 263 intake comes out to 407.41......
Let's say going to a larger bore unresticts the head flow and gains 5 cfm for intake and exhaust...
The rwhp then jumps to 416.82.......if by 10 cfm for example it jumps to 426.22..... for the stock TFS heads with 236 flow the rwhp numbers came in at 344.37.....now consider there are a lot if other variances like compression, bore and stroke, intake changes, etc that can affect t power this is inline with actual power gains.....
Since the stock tfs heads rwhp number came in at 344 but with the stroker and 11.34 cr it made 393/398 to the tires...
426 compared to 344 for rwhp head potential is alot of difference but combo and set up with all the variations can get you close....since my car gained 20hp over other TFS heads on the 281 bore mostly because of increased flow at all lifts from the ported heads this shows that there is a lot of potential going to a big bore stroker compared the the 281 where the valves were shrouded.....good stuff..
My current ported heads with 214 exhaust flow and 263 intake comes out to 407.41......
Let's say going to a larger bore unresticts the head flow and gains 5 cfm for intake and exhaust...
The rwhp then jumps to 416.82.......if by 10 cfm for example it jumps to 426.22..... for the stock TFS heads with 236 flow the rwhp numbers came in at 344.37.....now consider there are a lot if other variances like compression, bore and stroke, intake changes, etc that can affect t power this is inline with actual power gains.....
Since the stock tfs heads rwhp number came in at 344 but with the stroker and 11.34 cr it made 393/398 to the tires...
426 compared to 344 for rwhp head potential is alot of difference but combo and set up with all the variations can get you close....since my car gained 20hp over other TFS heads on the 281 bore mostly because of increased flow at all lifts from the ported heads this shows that there is a lot of potential going to a big bore stroker compared the the 281 where the valves were shrouded.....good stuff..
So turns out the guy with the 323 stroker I met a few times...same engine builder and tuner....my engine guy Dave from maconmoore performance was trying to get me to build a 323 stroker at the time and another guy he ended up building for.... dave use my car as a baseline for compression and parts set up...
So the question comes down to this.....what does it take to get 400 + to the tires ourt of a 2v Naturally aspirated....
1. 5.3l short block (FRPP has a BOSS 5.O Block and can use the Eagle Stroker Crank, rods, and will need 94mm bore pistons - The block has been backordered for the past 15 months due to supply chain issues) (NOTE: There are several places that can resleeve an aluminum block or stand block to 94mm - using an aluminum block you get the weight savings and the resleeve is 1900) I will use L&M engines as they are one of the best) I will put up part numbers for all items once I start sourcing and buying.
2. Full exhaust....specifically....kooks long tubes 1 5/8 and x pipe, cats deleted with 2.5 in exhaust....I use magnaflow...the guy with the stroker used Borla I believe..
3. Full bolt ons...i.e. CAI, TB combo, bigger injectors, under drive pulleys, maf, electric water pump, aluminum flywheel, DS, or lighter 9.5 in stall converter... any other tweaks to gain a few ponies.... other things like deleting AC with idler pulley, Power steering, etc... can free up some ponies... I am keeping all mine but just wanted to note...
4. 11.3 or higher CR... key is 190 to 195lbs at cylinder pressure with 93 octane as this is the safe max threshold.....or if e85. which can handle 14 to 1 cr safely...... I will be dynoing on 93 pump gas but will use torco octane booster for drag racing and hard pulls... 1 can with 7 gallons of gas raises 93 octane by 7pts or 100 octane.... with a full tank and 1 can it should be around 96-97 octane... added insurance for higher CR Cars...
5. TFS Heads....stock could get you there with a 11.6 or higher cr on pump gas.... ported heads should easily get there with 93.. remember...for every 1 pt in compression is equal to 4% more power across the board..
6. Correct cams....off the shelf are very limited and often not a good option....anything with .575 lift or higher...around 238 to 244 duration should be enough and maintain perfect drivability.....MHS offer a stage 4 and 5 cam that would work perfectly for the 5.3 liter and would be like running a stage 2-3 cam in this set up....
7. Intakes....both the PI and Bullet can get there depending on CR and matched mods....that is if you want over 400 hp and tq..... with a carburated eddy set up or eddy with 6061 injection set up can get to 430 to 440 but tq will come in around 330 to 340...so trade off in tq...same with TFS intake.....eddy you will spin to 6400 to 6900 or higher for peaks or TFS intake from 6700 to 7500 with right cam set up...so 135lbs or dual pac springs will be needed with these intakes......with pi intake with 78mm bbk tb or bullet intake with ported heads should have peak power from 5900 to 6300 depending on cams used...with 125 or 135lbs springs needed.. It would be interesting to see if any port work or extrude honing of the Bullet intake could improve the power curve at all...
The 323 stoker combo that put down 393/398 could easily hit 420 to 430 with a 12 to 1 Cr on E85 with heads ported so the combo was just a few tweaks away...possibly just a ported TFS R head with .610 to .615 lifts with the stage 4 cam profile would have hit 420 to 430 on pump gas...
So more cubes, high CR, and all supporting parts...5.3l base engine...
1. 5.3l short block (FRPP has a BOSS 5.O Block and can use the Eagle Stroker Crank, rods, and will need 94mm bore pistons - The block has been backordered for the past 15 months due to supply chain issues) (NOTE: There are several places that can resleeve an aluminum block or stand block to 94mm - using an aluminum block you get the weight savings and the resleeve is 1900) I will use L&M engines as they are one of the best) I will put up part numbers for all items once I start sourcing and buying.
2. Full exhaust....specifically....kooks long tubes 1 5/8 and x pipe, cats deleted with 2.5 in exhaust....I use magnaflow...the guy with the stroker used Borla I believe..
3. Full bolt ons...i.e. CAI, TB combo, bigger injectors, under drive pulleys, maf, electric water pump, aluminum flywheel, DS, or lighter 9.5 in stall converter... any other tweaks to gain a few ponies.... other things like deleting AC with idler pulley, Power steering, etc... can free up some ponies... I am keeping all mine but just wanted to note...
4. 11.3 or higher CR... key is 190 to 195lbs at cylinder pressure with 93 octane as this is the safe max threshold.....or if e85. which can handle 14 to 1 cr safely...... I will be dynoing on 93 pump gas but will use torco octane booster for drag racing and hard pulls... 1 can with 7 gallons of gas raises 93 octane by 7pts or 100 octane.... with a full tank and 1 can it should be around 96-97 octane... added insurance for higher CR Cars...
5. TFS Heads....stock could get you there with a 11.6 or higher cr on pump gas.... ported heads should easily get there with 93.. remember...for every 1 pt in compression is equal to 4% more power across the board..
6. Correct cams....off the shelf are very limited and often not a good option....anything with .575 lift or higher...around 238 to 244 duration should be enough and maintain perfect drivability.....MHS offer a stage 4 and 5 cam that would work perfectly for the 5.3 liter and would be like running a stage 2-3 cam in this set up....
7. Intakes....both the PI and Bullet can get there depending on CR and matched mods....that is if you want over 400 hp and tq..... with a carburated eddy set up or eddy with 6061 injection set up can get to 430 to 440 but tq will come in around 330 to 340...so trade off in tq...same with TFS intake.....eddy you will spin to 6400 to 6900 or higher for peaks or TFS intake from 6700 to 7500 with right cam set up...so 135lbs or dual pac springs will be needed with these intakes......with pi intake with 78mm bbk tb or bullet intake with ported heads should have peak power from 5900 to 6300 depending on cams used...with 125 or 135lbs springs needed.. It would be interesting to see if any port work or extrude honing of the Bullet intake could improve the power curve at all...
The 323 stoker combo that put down 393/398 could easily hit 420 to 430 with a 12 to 1 Cr on E85 with heads ported so the combo was just a few tweaks away...possibly just a ported TFS R head with .610 to .615 lifts with the stage 4 cam profile would have hit 420 to 430 on pump gas...
So more cubes, high CR, and all supporting parts...5.3l base engine...
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So I have been doing a lot of research on the TFS heads....185 vs the 195 R heads... I know there are casting differences between the 185 and 195 casting which support the larger intake valves...but both have options fo .650 lifts so.trying to establish some numbers on flows and lifts and if these are just spring and retainer set ups vs castings to go from .580 to .650 lifts....and which way to go.....I need to verify with Trick Flow and some of the main shops that do these heads but here are my findings...
TFS advertises a few different versions of heads now....185s with 90lbs @ .600 lift, 125lbs @ .580 lift , and R versions dual 150lbs springs with .650 lifts...
I am trying to find out if the springs are all interchanable on the heads and if the 185 44cc heads can support .650 lifts with adding dual pact 150lbs springs...
Being able to go to a .610 to .620 lift camshaft would be ideal and wanted to see if this is possible...I know that the 185s can't be upgraded to the larger intake valves as the R head has taller towers and port design changes....just some more thoughts as I look for options to improve valve train....
As of now....I am looking to go 125lbs springs with . 575 lift cams.....if I could do the dual pact springs and get. 650 lift capacity I will go .610 lift for cam....
TFS advertises a few different versions of heads now....185s with 90lbs @ .600 lift, 125lbs @ .580 lift , and R versions dual 150lbs springs with .650 lifts...
I am trying to find out if the springs are all interchanable on the heads and if the 185 44cc heads can support .650 lifts with adding dual pact 150lbs springs...
Being able to go to a .610 to .620 lift camshaft would be ideal and wanted to see if this is possible...I know that the 185s can't be upgraded to the larger intake valves as the R head has taller towers and port design changes....just some more thoughts as I look for options to improve valve train....
As of now....I am looking to go 125lbs springs with . 575 lift cams.....if I could do the dual pact springs and get. 650 lift capacity I will go .610 lift for cam....
So going to order the Forged Eagle stroker crank and rods next week as these are in stock..... Eagle offers a coating surface called ESP Armour...they claim this adds upto 16.5 to 25hp with just a coating alone with independent testing from cranks without on the big blocks they and other shops tested....was repeatable in their testing and for other shops..for only 240.00 for the crank coating and 115.00 for the rods.....
Has any tried this coating? It's the little details I will be working on....
Also, would anyone recommend crank bearings to use...i see clevite and King make some of the best and some have coatings and treatments as well.... any help or guidance would be appreciated...
Has any tried this coating? It's the little details I will be working on....
Also, would anyone recommend crank bearings to use...i see clevite and King make some of the best and some have coatings and treatments as well.... any help or guidance would be appreciated...
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