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Discussion Starter #41
Fresh hone and total seal rings coming.
 

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Discussion Starter #45
It's back together and hitting the dyno again in the next week.
 

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Discussion Starter #47

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Discussion Starter #48
https://youtu.be/BaTf1VIEKww

The refreshed and slightly altered mill is ready. In 2018 I got a good deal on some afr315s and wondered if they would outperform my ported afr265s. I did a typical magazine test and used the same cam. The 315s were a bit lazier down low. I did some spring changes in the distributor to close that gap on the loss in 60'.
Right before drag week I installed a Chris Straub custom cam for my combo. Things didn't seem to pickup as much as I had hoped. I wanted a single digit 3600 lb NA street car and my times were not there. During drag week that year Chris held an event and we got to talk and see his place. It was a really cool event he put on. He mentioned the track elevation and possible DA. I made the decision to run open header at Bristol. That opened my eyes to how my car was being slowed down by my 3" exhaust. More than adequate for previous engines. After drag week on a cool autumn night I went 10.06 @ 133. So close to my goal.
This off season I talked to my local machinist about how I wanted to know what heads and intake and what cam presented the best possible chance to meet my goal. Shane Fessler was very interested to see this as well so we set out to test my options.
Option 1. 496 with custom CS cam and 315s. This made 692 hp with a mid pipe and probably 710 if we went open header but we didn't because we wanted it in race trim at the time.
Option 2. was using borrowed dominator and sniper jr, this made about the same power as with my vic jr and 4150 with mod pipes. We removed the mid pipes and bang 715 hp.
We did muffler testing as well and now I know what to run on the street.
Option 3. My Fessler ported afr265 heads with CS cam. This would bump the compression from 10.3 to 11:1. The dyno was acting up when it was time to test so we never had a solid answer. The numbers seemed inflated but better than anything to that point but we couldn't trust them.
We did the torque plate kiss of a hone and added some total seal rings. He had other customers to get through his shop and many get his dyno services. We assembled the engine last week then broke it in and pulled the handle on 4/26/20.
Option 3 now officially has numbers and it will be my race week and event mill until it gives up or I turn 50 (4 yrs). This has no choice but to get me single digits. We made 2 pulls and took the average of the data.
Hp 726 at 6200 rpm
Lb ft 665 at 5000 rpm
I will be spraying the car at some events but hope to do rocky mountain race week NA class again with my Fitech.
 

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Good job getting the blow by under control.

Why is so much fuel being drawn out of the accelerator pump discharge nozzles? Looks like a lot of fuel!
 

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Discussion Starter #50
Good job getting the blow by under control.

Why is so much fuel being drawn out of the accelerator pump discharge nozzles? Looks like a lot of fuel!
Even with that it was lean in the beginning and in the zone by the end. He wanted to mill the nozzles a little but I mostly run a Fitech so I didn't want to spend too much time on it. The carb is hardly used.
 
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Would love to see options 1,2 and 3 curves laid over each other with avgs as well. I would bet option 3 was better down lower and through most of the curve?
 

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https://youtu.be/BaTf1VIEKww

The refreshed and slightly altered mill is ready. In 2018 I got a good deal on some afr315s and wondered if they would outperform my ported afr265s. I did a typical magazine test and used the same cam. The 315s were a bit lazier down low. I did some spring changes in the distributor to close that gap on the loss in 60'.
Right before drag week I installed a Chris Straub custom cam for my combo. Things didn't seem to pickup as much as I had hoped. I wanted a single digit 3600 lb NA street car and my times were not there. During drag week that year Chris held an event and we got to talk and see his place. It was a really cool event he put on. He mentioned the track elevation and possible DA. I made the decision to run open header at Bristol. That opened my eyes to how my car was being slowed down by my 3" exhaust. More than adequate for previous engines. After drag week on a cool autumn night I went 10.06 @ 133. So close to my goal.
This off season I talked to my local machinist about how I wanted to know what heads and intake and what cam presented the best possible chance to meet my goal. Shane Fessler was very interested to see this as well so we set out to test my options.
Option 1. 496 with custom CS cam and 315s. This made 692 hp with a mid pipe and probably 710 if we went open header but we didn't because we wanted it in race trim at the time.
Option 2. was using borrowed dominator and sniper jr, this made about the same power as with my vic jr and 4150 with mod pipes. We removed the mid pipes and bang 715 hp.
We did muffler testing as well and now I know what to run on the street.
Option 3. My Fessler ported afr265 heads with CS cam. This would bump the compression from 10.3 to 11:1. The dyno was acting up when it was time to test so we never had a solid answer. The numbers seemed inflated but better than anything to that point but we couldn't trust them.
We did the torque plate kiss of a hone and added some total seal rings. He had other customers to get through his shop and many get his dyno services. We assembled the engine last week then broke it in and pulled the handle on 4/26/20.
Option 3 now officially has numbers and it will be my race week and event mill until it gives up or I turn 50 (4 yrs). This has no choice but to get me single digits. We made 2 pulls and took the average of the data.
Hp 726 at 6200 rpm
Lb ft 665 at 5000 rpm
I will be spraying the car at some events but hope to do rocky mountain race week NA class again with my Fitech.
The power with the AFR265 just shows the bigger is better mentality is wrong! And yet many people still argue that the 265's are way too small for an engine unless you are making a street or tow vehicle.

And I still argue with guys that the Flowmasters are huge power losers!
 

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Discussion Starter #54
Would love to see options 1,2 and 3 curves laid over each other with avgs as well. I would bet option 3 was better down lower and through most of the curve?
Did you see the graph at the end of the video. That was optiona 2 vs 3. Option 1 was slightly lower than 2 but didn't tha e open headers. I only did mid pipe testing to see what the car config numbers looked like.
 
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Always enjoy the back to back dyno testing Thanks for posting
Question what spring pressure Did you use ?? .904 or .842 ?

On My Foxwell 9.8 ci
4” stroke 4.350 bore 475 ci Straub hyd roller I used 2” headers but with 3” collectors then later 3 1/4 the 3” collector made same torque down lower but was off 12 hp from the 3 1/4 but Chris told me should have had 3 1/2” collector So maybe left some peak power
Power peaked st 6500 but only off 3-4 at 6900
So your 21/8” was pbly Close what collector diameter ?

My big bottleneck was my dual plane eddy rpm airgap Im sure a single plane would have got me to 700 Hp Depending on collector size made 665 /680hp
 

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Discussion Starter #56
Always enjoy the back to back dyno testing Thanks for posting
Question what spring pressure Did you use ?? .904 or .842 ?

On My Foxwell 9.8 ci
4” stroke 4.350 bore 475 ci Straub hyd roller I used 2” headers but with 3” collectors then later 3 1/4 the 3” collector made same torque down lower but was off 12 hp from the 3 1/4 but Chris told me should have had 3 1/2” collector So maybe left some peak power
Power peaked st 6500 but only off 3-4 at 6900
So your 21/8” was pbly Close what collector diameter ?

My big bottleneck was my dual plane eddy rpm airgap Im sure a single plane would have got me to 700 Hp Depending on collector size made 665 /680hp
.842 lifters, the springs are the PAC afr hyd roller springs. Something like 195 seat and high 400s open
My collectors are 3 1/2. I had 1 7/8 primary tubes with 3 1/2" collectors and there was 20-25 hp difference in the usable rpm range.
 

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Discussion Starter #57
The power with the AFR265 just shows the bigger is better mentality is wrong! And yet many people still argue that the 265's are way too small for an engine unless you are making a street or tow vehicle.

And I still argue with guys that the Flowmasters are huge power losers!
My out of the box heads didn't net the desired results. The intake ports have been worked over. There is a picture in my phase 3 496 thread about the afr315s
 

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The power with the AFR265 just shows the bigger is better mentality is wrong! And yet many people still argue that the 265's are way too small for an engine unless you are making a street or tow vehicle.

And I still argue with guys that the Flowmasters are huge power losers!
My out of the box heads didn't net the desired results. The intake ports have been worked over. There is a picture in my phase 3 496 thread about the afr315s
I recall that, but even worked they still have far less port volume than the 315’s. The results go against many people’s thinking.
 

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Discussion Starter #59
I recall that, but even worked they still have far less port volume than the 315’s. The results go against many people’s thinking.
They should be over 300 and less than 315. The cross section I once had measured was not much smaller.
A lot of 496s with 345 heads claiming they run great. My 60' suffered from the change and that was with the distributor spring changes. Hopefully if things open up I will be at a track in 10 days.
 
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