Disappointing Dyno

[Sam]

I just had a tuning shop in Calgary (AutoDream) do a bunch of upgrades to my JZA70 Supra. I had some Brian Crower 264 cams and 440cc injectors installed. I also had some Brian Crower spings and retainers, but they said it couldn't be done because they had to be specially machine pressed in. ??? I also got an AEM wideband with a tune via my Apexi SAFC II.

I came into the shop with a full 3 inch exhaust, no cat, stock Y-pipe, stock turbos, Turbosmart manual boost controller, and a Blitz Access ECU.

After everything was said and done I only made 292 rear-wheel HP @ 6326rpm. It doesn't tell me my max torque, but at 6326 rpm I made 243 ft.lbs. Early in the torque band it looks like I reached near 300 between 4000 and 5000 rpm.

I don't get it though, I thought with these upgrades I'd making plenty of power. In fact, my car feels more sluggish than before. It went like a raped ape before with the stock cams, and now it feels slightly less powerful!!! They tried to tell me that the Blitz ECU was tuned too aggressively and I could have been making more power before, but it was at a dangerous level. I would have been running too lean.

Well, whatever, I was under the impression that when you do cams in a 1JZ it's supposed to be night and day difference...Only now I don't make any power until well after 4000 rpm...

Anyone have any suggestions? Is this weak sauce amount of power normal? I feel quite ripped off since I paid them $2400 for their services...

 

[Tanya]

Graph?

What are your air fuel #s?

Do you have adjustable cam gears and if so, did the shop adjust them for tuning, or what?

 

[josh930]

Did they shim the cams? Do you have a wideband and afc? Retainers and springs had to be machine pressed in??? What the hell are they talking about? Sorry, but it sounds like you did get ripped. They have no clue what there talking about.

 

[chefma70]

sucks to hear man .but ive heard the same story a few times.use your stock cams!my friend was using crower cams and didient like the results and then put the stock cams back i and he said it was alot better.

 

[Sam]

I have a photocopy of the graph, but I'm still in Calgary (I live 8 hours east of here), so when I get home tonight, I'll scan it and post it up. And I don't have adjustable cam gears, just the stock ones.

Based on what I'm seeing on the dyno graph, the numbers for the Air/Fuel ratios look pretty good. Starts off at around 15.10 and ends off at 10.51.

And it doesn't even look like the revved it the red line. It looks like they took off the gas right at at 6400 rpm. The horsepower was still climbing so maybe it would have been a bit higher...who knows.

I'll post the dyno graph tonight when I get home at light midnight.

 

[OneJSupra]

Yea something's screwed up. I made 296rwhp @ 10psi with my stock twins, stock injectors and stock everything else except with full 3" exhaust.

 

[josh930]

Ask them why they didnt rev it more and find out if they shimmed the cams. That can make a pretty big difference. Also, I dont think that stock Y pipe is helping out too much with the cams

 

[tbcmorris]

for those mods thats low

 

[10secdream]

Sounds to me like your timing might be off. Double check to make sure the cams were installed correctly. Trust me you should be making much more power. What boost are you running? Also sounds like your tune isn't very good. 10.51 is a little rich if you ask me. Mid 11's I would call safe.

 

[tissimo]

How much boost?

Cams wont do much with stock twins.

 

[Zumtizzle]

did they shim the valves?

 

[tbcmorris]

did they shim the valves?

i was just thinking this as i revisted this thread...

 

[soapra]

Cams need to be degreed and shimed. I have done dyno pulls with your mods and had results in the 350 range with stock twins and stock y pipe. When ever you do upgrade cams you need to use cam gears.

 

[Sam]

Ok, what is this shimming business? You mean I have to machine my brand new cams? You can't just put them straight in?

And no, they didn't do anything with my valves, they pretty much just slapped the new cams in.

 

[Zumtizzle]

Knew it.

You can really burn up valves if you don't do this right.

Find a New Shop too. This one obviously shouldn't touch a car let alone a performance build.

http://www.youtube.com/watch?v=EpH7VftH3_I

http://www.youtube.com/watch?v=vQ9ccGXtZL0&feature=related

Watch through this.

 

[RacerXJ220]

Depending on the cam manufacturer, you may not need to adjust the cam gear or the shims.

Look at ZaZZn's power on the 67 with BC cams, mid 600's @ 24psi on pump with zero degree changes made to the cam (straight up and down IIRC), but they are 2JGTE cams.

OP is using Brian Crower, not Crower Cams.

My Jun 272 intake cam dropped straight in with no new shims required after I had properly shimmed the stock cam before installing this one and I enjoy this cam with the stock cam gear and zero adjustments. I have read similar accounts from SF describing their HKS or Jun install going so smoothly maybe one, or even none of the shims needed to be replaced and a lot of people run these cams straight up and down making very good power.

Yet the only way to verify anything is to actually measure clearances and opening events of both cams, and this will determine your adjustments if they are required and all should be measured properly before reinstalling the cam covers.

This is why I have only one adjustment wheel, and it is for my exhaust cam.

Edit: something else, if the clearance between the lobes and the shims are too great, shim spitting is a real possibility. I recommend you check this out yourself, it is not at all difficult to just run a feeler gauge through each one. Just remove the valve covers and rotate the crank a few times in the process.

What RPM are you shooting for? Just saying, you may not need springs with those 264's.

 

[Sam]

Dyno graph added to original post.

RacerXJ220, I want to make power all the way to 7,200 rpm (for some reason, my blitz access ECU still has the stock RPM limiter)

Also, I noticed today that my car had quite a hard time starting. It took 3 sets of 2 second intervals of cranking to get it to start. And when it did, it didn't roar to life like it normally does, it sort of gradually sputtered itself to life.

During the day at WOT it seems to accelerate nicely (similarly to it's previous performance before the new cams and injectors) but tonight I took it out for a spin again for further testing and it sort of hiccups once in awhile during WOT.

Could timing be an issue here? My car definitely sounds different than before. The idle is quite loppy and slightly shakes the vehicle. During acceleration, it produces a difference noise. Still very nice, but different, more raspy. I'd expect it's from the different duration cams, but who knows. I wish some of you guys lived near here, that would just be a dream come true.

 

[Sam]

Cams need to be degreed and shimed. I have done dyno pulls with your mods and had results in the 350 range with stock twins and stock y pipe. When ever you do upgrade cams you need to use cam gears.

In the Brian Crower cam group buy, Zazzn said that these cams can be simply dropped in without any modifications. Maybe I'll give Brian Crower a call and see what they say.

 

[SupraClaou]

What RPM are you shooting for? Just saying, you may not need springs with those 264's.

I have some HKS 264 cams ready to drop them in...on my 2jzgte.
Want to rev the engine till 7800 rpms (stock is 6800).
Should I need the high performance spring & retainer kit???
And if Yes,which is the best way to put these on?
I heard that it is possible to install the springs/retainers without having
to take the head off! Is this true?

 

[10secdream]

Sam I would double check your timing. Make sure the timing marks are pointing straight up and the crank lined up. Even with cams you should only have a slight lope and it should not affect the starting. I really think something is off here.

On a side note I live in the next province over