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Piglet's Rebuild Of His Busted Tomei 2.8

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Piggaz Grand Master

Piggaz

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6 minutes ago, ActionDan said:

What am I missing with these EFRs? 

I thought you just took a look at the comp map, aimed for a decent efficiency island for your power goal, as you do with any turbo choice, and that was that?

Can't think of when I've seen people talking about turbine speed so intently with other brands. Are the EFRs particularly sensitive to overspeeding? 

It's got to do with the turbine wheel. Because of the light weight wheel, the downside is that it has a maximum RPM that it doesn't like going over. It's not exactly a secret. 

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Piggaz
Piggaz

Car is finally booked into Insight on the 19th of April for the ECU, fuel system and sensor wire in plus the tune. Thats the good news. The bad news is that V-cam aint gonna fit with my pistons and ho

Piggaz
Piggaz

Small update.... ITS RUNNING. Fired first go! Smells like burnt dust apparently .

Piggaz
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A 9174 would just make the EGP pressure issue worse and in my mind it seems like a bit of a GT RS shit going on. Not that it's horrendously bad (It wouldn't be no twin buttplug pressures), That's NOT

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Lithium Grand Master

Lithium

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There have been a few failures, but not THAT common.  A lot of the earlier EFR failures which are documented were actually more to do with the early build issues than actual overspeeding

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Piggaz Grand Master

Piggaz

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Worth noting that the tuner at Insight who tuned that Tilton Evo (won WTAC 3 times on the trot) has never blown an EFR up, ever.

Sensors run, turbos spun to their limit. 

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acsplit Veteran

acsplit

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On 4/25/2017 at 2:33 PM, SimonR32 said:

Honestly I'd have given a EFR8374 a go if it wasn't for all the fab... Instead I seem to be stuck with the 6262 (not being a bad thing) but now I'm up to 5 sets of cams that have been in the car haha

Latest better be awesome considering I've gone backwards 4 times in some way shape or form

I assume you are chasing some response gain?

Props to you for actually trying 5 different combinations.....

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acsplit Veteran

acsplit

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4 hours ago, ActionDan said:

Post some f**king numbers >.<

My car is delayed so I need something. 

I see the dyno thread got a bump at least. 

If you want to see numbers just go to the precision thread :4_joy:

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acsplit

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4 hours ago, Piggaz said:

Worth noting that the tuner at Insight who tuned that Tilton Evo (won WTAC 3 times on the trot) has never blown an EFR up, ever.

Sensors run, turbos spun to their limit. 

Yeah but if you had a plug in Halaltech it would already be tuned.

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SimonR32 Grand Master

SimonR32

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On 25/04/2017 at 3:44 PM, Piggaz said:

5 sets of cam setups? What are you chasing to warrant 5 different setups? You could have had a EFR setup with change.

First motor had Grex cams from Japan but dropped a valve guide so I purchased some Tomei Type-R poncams for the new motor... Installed but turns out it already had Type-B poncams. The Type-R's didn't really want to make enough power so I chucked the Type-B's in to see how they went. They were average at best still not making all the top end power and a fair wack laggier. Needed to do head gasket so we did the head (with minor porting), guides etc and chucked in some wiz bang Kelford split duration 274 jobs. They made good power (most it's ever made and maxed out the turbo) plus plenty more grunt on lower boost settings but lacked a fair bit below 4500rpm, especially on road/track. So went back to Kelford and had signifcant discussions and planning via email to come up with a new custom grind. They are in the hole now and just need a tune, fingers crossed they are good otherwise I'm going to try find the old Grex and buy them back haha

So in terms of cash, once I sell the Kelford split cams to someone with a bigger turbo or stroker I should be less than $1000 out of pocket for all the testing.

Basically I want my cake and eat it, turns out the Grex cams were probably almost there, now the never ending search to get it back to where it was or a little better :)

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Piggaz Grand Master

Piggaz

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260 poncam strikes again ?.

What sort of grind did you decide on with Kelford? Lift at 50 thou (or 1 mm) and lift? Can understand if you don't want to release that info though ?.

Considered pulling the head off to relieve it and run more lift with a not so long duration? 

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r32-25t Grand Master

r32-25t

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6 hours ago, SimonR32 said:

First motor had Grex cams from Japan but dropped a valve guide so I purchased some Tomei Type-R poncams for the new motor... Installed but turns out it already had Type-B poncams. The Type-R's didn't really want to make enough power so I chucked the Type-B's in to see how they went. They were average at best still not making all the top end power and a fair wack laggier. Needed to do head gasket so we did the head (with minor porting), guides etc and chucked in some wiz bang Kelford split duration 274 jobs. They made good power (most it's ever made and maxed out the turbo) plus plenty more grunt on lower boost settings but lacked a fair bit below 4500rpm, especially on road/track. So went back to Kelford and had signifcant discussions and planning via email to come up with a new custom grind. They are in the hole now and just need a tune, fingers crossed they are good otherwise I'm going to try find the old Grex and buy them back haha

So in terms of cash, once I sell the Kelford split cams to someone with a bigger turbo or stroker I should be less than $1000 out of pocket for all the testing.

Basically I want my cake and eat it, turns out the Grex cams were probably almost there, now the never ending search to get it back to where it was or a little better :)

Are you suggesting those idiots on the forum were right and that increasing duration decreases bottom end torque and makes a turbo come on later? And anyone who bought bigger cams to improve response has actually done the wrong thing?

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Lithium Grand Master

Lithium

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16 minutes ago, r32-25t said:

Are you suggesting those idiots on the forum were right and that increasing duration decreases bottom end torque and makes a turbo come on later? And anyone who bought bigger cams to improve response has actually done the wrong thing?

Wasn't that pretty much unanimous?   Well the first part was, the second part would be a little bit of a blurred line.

 

  I can't remember the specifics of the thread but the Kelfords were an interesting cam and there was hope they'd be pretty cool and to be fair- without checking the thread I'd have hoped the compromise wouldn't be as bad as it sounds it was, but my argument is that the overbearing "any longer duration is bad, fullstop" is a bit misplaced, the trick is finding a match between the rest of your setup and how you use it.

It's a shame they haven't worked as well as you'd hoped, I actually had some hope for them - would have liked to have seen them "happy" by 4500rpm, especially how Kelford marketed them.

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r32-25t Grand Master

r32-25t

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Unfortunately it's not unanimous because to many people still the the rb26 works different to every other combustion engine and believe fitting bigger cams will improve bottom end 

apart from that there was a lot a sarcasm in my post

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Lithium Grand Master

Lithium

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3 minutes ago, r32-25t said:

Sarcasm is lost on you isn't it?

No, not at all.  I am one of the people you appear to be mocking as I feel that the blanket "shorter duration is better" statement glosses over things too much.

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No Crust Racing Grand Master

No Crust Racing

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Good luck Simon. I've got Kelford L182-A baby cams going in now, all indicators point to them being a better option than the Tomei stuff. My goal is to maintain similar response while allowing the motor to breath up top. Happy to dial the gears for response at the expense of the top end as a compromise. I had a really good chat with Josh about my setup/goals and realistic expectations and we settled on those cams with the intent of me creeping over 500rwhp on -9s if possible. 

He also advised me to go the BC springs given the price I got them for rather than trying to insist I buy his springs, which had lower seat pressure. 

Very good to deal with, especially when it turned out the Cams the seller gave me were 32/33 CAS lol He modified the exhaust Cam keyway in a day and express posted it back to me, customer service is excellent. 

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