Crawford Billet Power Blocks

[Boss Paco]

Yes. Test it with FI. I wanna see gains with a turbo.

[Slowbaru]

Originally Posted by wparsons

Good review, just wish their dyno included the AFR as well.

Not to be a negative nelly, but 4whp is a far cry from the claimed 19hp. Yes the area under the curve increase is far more impressive than the peak hp gain suggests, but it leads me to suspect that the crawford dyno with the PB was a tuned run vs a totally stock car on the baseline.

I agree, but peak gain was 11.5 on a conservative dyno.

[TwinturboCamry]

Can I stack two sets of power blocks together and double the power?

[TwinturboCamry]

pls respond

[xjohnx]

Someone pass the sawzall, lets see how they do with the innovate!

[nelsmar]

Originally Posted by wparsons

Good review, just wish their dyno included the AFR as well.

Not to be a negative nelly, but 4whp is a far cry from the claimed 19hp. Yes the area under the curve increase is far more impressive than the peak hp gain suggests, but it leads me to suspect that the crawford dyno with the PB was a tuned run vs a totally stock car on the baseline.

i have attached the dyno from motoiq but with some markings.



I want you to look over both. Note that the cursor on the crawford dyno is at roughly 6,359 RPM. This is showing the power at that RPM not the peak RPM. The 4WHP gain was "4WHP @ peak" Not "4WHP Peak gain". There is a significant difference. If you look at the green lines i drew thew are exactly the same size (i copy and pasted). This line indicates roughly 9WHP @6,200RPM gain. This is a rough estimate of the peak gain, not gain at peak. If you do rough estimates the right green line is roughly 149WHP. The baseline however shows roughly 140WHP. 149/140 = 6.4% gain. Mind you I am estimating numbers. As I don't have the original plot to use to verify exact numbers. And in fact I am WRONG here is a quote from the article:

Torque was 126.2 lb/ft @6200 rpm, a gain of 8 lb/ft. The peak power gain was 11.5 hp @ 6200 rpm and peak torque gains were pretty much 8 lb/ft.

So if this is the case then lets calculate our HP @ 6200.

126.2/5252 * 6200 = 148.9HP.
148.9 - 11.5 = 137.4

What is our % gain?
148.9 / 137.4 = 8.36%.

Now lets repeat this using crawfords dyno in which we have the numbers written on the chart.
206.11HP at peak gain @ 6359RPM.
187.88 baseline @ 6359.

What is Crawfords % gain?
206.11/187.88 = 9.7% gain.

So sure crawford saw roughly a 1.32% higher gain than this user. But thats pretty damn close.

This is a great example of "reading" the text from a dyno's gain reports vs actually analyzing the report. If you want to actually view gains via text it is best to use AVG WHP/WTQ gains to do comparison and use them in % not WHP. It looks like crawford is trying to use a compensation to compare to a dynojet or something of the sorts which is why their dyno is reading so high. Again if you look at their chart you will see AXLEPOW VS POWER which is corrected vs uncorrected. This is why simply posting "my car has xxWHP/xxWTQ" is rubbish. Because maybe you have a linear tq curve, or a flat tq curve and the difference is quite big when actually driving the car.

So what am I saying?
Yes I do see the 19WHP gain. If you were to get the same % gain that crawford saw you would see 13.3WHP peak gain. This article posts an 11.5 gain. This is fairly close.

If this is sustained post tuning then this is an extremely good power / $$ ratio mod for NA cars.

[nelsmar]

Originally Posted by TwinturboCamry

Can I stack two sets of power blocks together and double the power?

Originally Posted by TwinturboCamry

pls respond

I know you are kidding... but... LOL possibly.

Originally Posted by sw20kosh

This has been done a lot on rotary engines. You alter the shape of the torque curve by adjusting the length of the intake runners. They actually chop off sections of their intake runners to shorten them to extend the torque curve further to the right.

What crawford has done is altered the torque curve (notice the HP peak shift to the left and look at where torque starts to fall off up top) and if it truly is a stock ECU tune... the ECU/engine loves the heck out of this new intake runner length. You get a much sharper/drastic high rpm fall off of torque from this peak though (fall off of torque is now at ~6400 vs the stock ~6700 rpm.

The basic principle:





Has any OEM played with variable intake runner length technology?

[Boxer486]

So how tall are the spacers exactly?

[nelsmar]

Originally Posted by Boxer486

So how tall are the spacers exactly?

35.8MM

[White64Goat]

Originally Posted by TwinturboCamry

pls respond

three stacks................

[White64Goat]

Originally Posted by Thorpedo

I'm not digging that loss above 7k...

If max HP is now at 6300-6400 instead of 7000, how is that a negative? Seems like less wear and tear on the internals to me. I know you'd like to see the HP continue to go up, but if this mod lowers the rpm's with the same amount of peak HP, it seems like a benefit to me.

[Crawford Performance]

Originally Posted by nelsmar

i have attached the dyno from motoiq but with some markings.

Attachment 71968

I want you to look over both. Note that the cursor on the crawford dyno is at roughly 6,359 RPM. This is showing the power at that RPM not the peak RPM. The 4WHP gain was "4WHP @ peak" Not "4WHP Peak gain". There is a significant difference. If you look at the green lines i drew thew are exactly the same size (i copy and pasted). This line indicates roughly 9WHP @6,200RPM gain. This is a rough estimate of the peak gain, not gain at peak. If you do rough estimates the right green line is roughly 149WHP. The baseline however shows roughly 140WHP. 149/140 = 6.4% gain. Mind you I am estimating numbers. As I don't have the original plot to use to verify exact numbers. And in fact I am WRONG here is a quote from the article:

So if this is the case then lets calculate our HP @ 6200.

126.2/5252 * 6200 = 148.9HP.
148.9 - 11.5 = 137.4

What is our % gain?
148.9 / 137.4 = 8.36%.

Now lets repeat this using crawfords dyno in which we have the numbers written on the chart.
206.11HP at peak gain @ 6359RPM.
187.88 baseline @ 6359.

What is Crawfords % gain?
206.11/187.88 = 9.7% gain.

So sure crawford saw roughly a 1.32% higher gain than this user. But thats pretty damn close.

This is a great example of "reading" the text from a dyno's gain reports vs actually analyzing the report. If you want to actually view gains via text it is best to use AVG WHP/WTQ gains to do comparison and use them in % not WHP. It looks like crawford is trying to use a compensation to compare to a dynojet or something of the sorts which is why their dyno is reading so high. Again if you look at their chart you will see AXLEPOW VS POWER which is corrected vs uncorrected. This is why simply posting "my car has xxWHP/xxWTQ" is rubbish. Because maybe you have a linear tq curve, or a flat tq curve and the difference is quite big when actually driving the car.

So what am I saying?
Yes I do see the 19WHP gain. If you were to get the same % gain that crawford saw you would see 13.3WHP peak gain. This article posts an 11.5 gain. This is fairly close.

If this is sustained post tuning then this is an extremely good power / $$ ratio mod for NA cars.

Thanks dude, its good to see that you get it.

[kiichiro]

Very curious to see fi results

[wparsons]

Originally Posted by nelsmar

Yes I do see the 19WHP gain. If you were to get the same % gain that crawford saw you would see 13.3WHP peak gain. This article posts an 11.5 gain. This is fairly close.

If this is sustained post tuning then this is an extremely good power / $$ ratio mod for NA cars.

I'm not going to argue with you on most of that, because you are right. I was reading the posted chart wrong, I just scanned quickly and assumed the power numbers shown in the right sidebar were the peak numbers, not the numbers at ~6400rpm.

Before: 187.88
After: 206.11

That's a delta of 18.23hp and is the number I was talking about compared to the 4whp motoiq got. Blame it on tired eyes not reading the graph right