Crawford Billet Power Blocks

[cslntuee]

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.

I have questions related to this two charts.
I am a daily driver, so low and middle range rpm are more important to me.


1. Why the motoiq dyno shows HP and torque improvement almost
full range (2000-6800), but Crawford only (4250-6800)?


2. Motoiq torque curve has triple peak in the range of 2000-3250,
is that normal? Crawford did not have.


Thanks.

[jng]

Dropped my car off at the workshop for them to install the BPBs. Post-installation, they mentioned that the car "seemed much slower". I have yet to verify this as am only picking the car up tomorrow... Anyone faced something similar? Would the ECU reset help?

[Lonewolf]

Originally Posted by jng

Dropped my car off at the workshop for them to install the BPBs. Post-installation, they mentioned that the car "seemed much slower". I have yet to verify this as am only picking the car up tomorrow... Anyone faced something similar? Would the ECU reset help?

An ecu reset followed by some relearning time (40-50 miles I believe) and the car should show its newfound power...

[stugray]

Originally Posted by jng

Dropped my car off at the workshop for them to install the BPBs. Post-installation, they mentioned that the car "seemed much slower". I have yet to verify this as am only picking the car up tomorrow... Anyone faced something similar? Would the ECU reset help?

IIRC - you need a tune with the BPBs.
Tests did show a reduction in performance with the stock tune.

[jng]

Thanks for the replies guys.

Told the workshop to disconnect the battery to reset the ECU so will see how that goes prior to getting my tune done. BPBs were the last step before I get my 86 tuned, as headers, over and front pipe installed weeks back.

[Lonewolf]

Originally Posted by stugray

IIRC - you need a tune with the BPBs.
Tests did show a reduction in performance with the stock tune.

Whose tests?

Taken straight from Crawford's site:

Crawford Performance is proud to announce our latest product, the Billet Power Block (BPB).
CNC machined from Billet 6061 aluminum, our BPB sandwich between the cylinder heads and the intake manifold to create longer intake runners. The lengthened intake runners enhance the volumetric efficiency of the engine which translated into an increase of 19 Horse Power, 15 Pound Feet of Torque and narrowed up the torque dip by 300RPM on a totally stock BRZ. Our BPB also works with any aftermarket tune, exhaust and intake components. Our original road testing was done in conjunction with our stage 1 reflash followed by extensive dyno testing with and without a tune.


With the way the above claims were written, you should be seeing some gains even on a stock car...so I'll leave others with them installed to chime in

***Either way, since op is getting a tune you should be able to make any adjustments needed to take advantage of the blocks...

[Luis_GT]

Originally Posted by stugray

IIRC - you need a tune with the BPBs.
Tests did show a reduction in performance with the stock tune.

No you don't... this is a intake spacer kit made by my local tuner... my car untuned before and after intake manifold spacers

You lose a bit at the top end... but then again I rarely shift at redline even at the track.

[xcelir8brz]

Installing Crawford BPB tomorrow.

[RevoG]

Installed mine tonight. Just took it around the block and not happy. But I have it booked for a retune first thing Sunday morning so that should solve my unhappiness.

Install not difficult but need more hands. Luckily had some fellow 86'ers over for assistance.

[xcelir8brz]

Ended up doing mine tonight. Two hours. White glove service. Reset ECU. Applied map to Unichip. Around the block. No bog. More testing tomorrow.

[Jmonty]

Mine are on order, should be here next week.

[Pixie_Niner]

Had mine in for a month or so and Im enjoying them.

From the day they were fitted I noticed a difference in torque through the mid range. What I have noticed over the past week with the temperatures being very varied here is on a cold day the ecu isnt sure what to do. Throttle response can be a bit jerky etc.

Remap is needed just dont have time.


Has anyone got these fitted to a turbo'd or SC car?

[raven1231]

Originally Posted by Pixie_Niner

Had mine in for a month or so and Im enjoying them.

From the day they were fitted I noticed a difference in torque through the mid range. What I have noticed over the past week with the temperatures being very varied here is on a cold day the ecu isnt sure what to do. Throttle response can be a bit jerky etc.

Remap is needed just dont have time.


Has anyone got these fitted to a turbo'd or SC car?

Shiv has and they lose power. They are not a good match for forced induction.

[xcelir8brz]

Anyone have this installed with a strut tower brace that clears it? I had to remove my brace. Looking for new brace.