421 Stroker with Trick Flow Heads/Intake Dyno - Redux

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Thank You for posting, it's helping to nudge my rudder in the right direction. I'm building a similar 408. Did you have any detonation on 92 octane with 11.0-1 compression? I was planning on 10.5-1, but if I can run 11.0-1, I'll do that. I appreciate you sharing this build with us. Paul.
 
Thank You for posting, it's helping to nudge my rudder in the right direction. I'm building a similar 408. Did you have any detonation on 92 octane with 11.0-1 compression? I was planning on 10.5-1, but if I can run 11.0-1, I'll do that. I appreciate you sharing this build with us. Paul.

You're very welcome. Happy to help.

Negative. No detonation at all. I used VP pump 92 Non-ethanol for the dyno. I cut and inspected every plug afterwards and we didn't find any specks on the porcelain using a magnifying glass. Plugs were gapped at .035

Depending upon the local fuel quality in your area you should be fine at 11:1. A word of caution is to do the math and get your true C/R. The online calculators do a good job to get you within a range, but if you really want to to know for sure, take the measurements and do the math. I've been off as much as .75 C/R before on other motors.

Good luck!
 
Just realized I forgot to post the video of the dyno day. Sucker was loud behind 2 layers of plexiglass.

 
Did you already have some parts? You should have a bunch more in it than that unless you already had parts...I count at least 7K of parts alone...

Couple of things: I have a dealer discount through Summit. I also ordered a lot of these parts prior to the price increases. I already had the block and some accessories.

Edit: All-in I'm at $6,756.91. I bought the headers off of a dead guy years ago. (Funny story about that)
 
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Starting phase 2 of this 421 build. Time to wake this engine up.

I finally got the car together at the end of Summer and it pulls hard! Of course, I can't leave anything alone so I'm installing a bigger cam and finally hooking the nitrous system up.

Bullet cams got me a new hydraulic roller and we increased the duration by +14 on the intake/exhaust and increased the lift to .611 using the 1.6 rockers. If my math is correct, it should increase peak power by 500-550rpm, which will put me around 6300rpms. That's where I wanted it initially.

I won't be removing the engine to dyno this new combo, but I will be taking it to a chassis dyno in the Spring.

Here's the new cam card:

20230125_204938.jpg
 
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sounds good!
question….I am assuming you are referring to the 6300 as where it will make peak power .
I might be all wet, but with the cam 250@50, I suspect the power peak will be somewhat lower than 6300 by a decent amount…. Guessing 5900-6000+-
 
i like it, you should have kept the 108 LSA possibly. Should sound similar now to this (250/250 @.050" / .620" Lift, 108LSA):



Michael
 

i like it, you should have kept the 108 LSA possibly. Should sound similar now to this (250/250 @.050" / .620" Lift, 108LSA):



Michael


Agreed. I'm actually upset about the LSA because I told them to keep everything the same besides the duration and lift.

I saw the 110 when I got it and was like "WTH!"
 
i like it, you should have kept the 108 LSA possibly. Should sound similar now to this (250/250 @.050" / .620" Lift, 108LSA):



Michael

That’s a pretty high lift on a moderate duration cam. Quite a ramp on those lobes! Sounds sick! Who’s header?
Agreed. I'm actually upset about the LSA because I told them to keep everything the same besides the duration and lift.

I saw the 110 when I got it and was like "WTH!"

Mathematically speaking, it should have been a 104 LSA.
It’s a big engine with a very small intake valve.
With the 110 LSA, it should carry the HP further out the rpm range.
 
Agreed. I'm actually upset about the LSA because I told them to keep everything the same besides the duration and lift.

I saw the 110 when I got it and was like "WTH!"




If that is indeed the case, wouldn't it be on the cam company to make it right? If they didn't provide what you asked for, you should get what you paid for.



FWIW I would think a 106LSA would suit this combo well. Either way, eager to see your results.
 
Bullet knows what they’re doing. If you spoke with them and made it clear that you wanted to extend the peak up a bit in rpm, he’s going to add intake duration and lsa. The 110 will loose a little through the middle but carry further up top.
 
Bullet knows what they’re doing. If you spoke with them and made it clear that you wanted to extend the peak up a bit in rpm, he’s going to add intake duration and lsa. The 110 will loose a little through the middle but carry further up top.

the wider 110 will work better when he sprays it
 
i like it, you should have kept the 108 LSA possibly. Should sound similar now to this (250/250 @.050" / .620" Lift, 108LSA):



Michael

Extremely cool car! And I love how you dressed the engine up it looks great. Can you share some detailed pictures of the brake lines around the master cylinder with the fender well headers? I have a set of huslers just like that and I'm trying to figure out how I'm going to do the brake lines.
 
Starting phase 2 of this 421 build. Time to wake this engine up.

I finally got the car together at the end of Summer and it pulls hard! Of course, I can't leave anything alone so I'm installing a bigger cam and finally hooking the nitrous system up.

Bullet cams got me a new hydraulic roller and we increased the duration by +14 on the intake/exhaust and increased the lift to .611 using the 1.6 rockers. If my math is correct, it should increase peak power by 500-550rpm, which will put me around 6300rpms. That's where I wanted it initially.

I won't be removing the engine to dyno this new combo, but I will be taking it to a chassis dyno in the Spring.

Here's the new cam card:

View attachment 1716039674
That should make a nice gain vs old cam. I have a very similar cam from bullet going in my new build soon. 256 261. Same lift on a 110. Can’t wait to try it. I have a 4.1 Ohio crank kit. I was pretty happy with their service
 
well here is a video of my first try with the 426 stroker 505hp 564 tq , changed pistons heads and intake after this run , then i put the engine on a stand and put the 450hp 340 back in the car 8mpg at $8.20 a galon was killing me 120 miles a day hurts the wallet . Will put the 426 back when it is done up right skip video to 5 minute mark
 
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