Piglet's Rebuild Of His Busted Tomei 2.8

[r32-25t]

And I'm still waiting to be proven wrong, cause every time someone fits longer duration cams the bottom end power drops, which is tested very easily by doing a before and after compression test

so until the dynamic compression then increases again at their higher rpm efficiency level they will always be left behind in the bottom end

[Lithium]

22 minutes ago, r32-25t said:

And I'm still waiting to be proven wrong, cause every time someone fits longer duration cams the bottom end power drops, which is tested very easily by doing a before and after compression test

so until the dynamic compression then increases again at their higher rpm efficiency level they will always be left behind in the bottom end

I think that is the point I've always made - I don't recall anyone ever saying longer duration cams pick up torque at the bottom, be interesting to see if you have any reference or if you are just winning a debate against a made up side       If you can make the compromise (read: less VE) in a part of the rev range you aren't using then you just use the part where your VE (or "dynamic compression" as you're saying) starts building beyond what the smaller cams can provide, then you are always winning.   You wouldn't use 288s and a Promod94 Precision for a GTR used for hill climbs, you wouldn't use 256s and a pair of -9s for Pro-class in WTAC and you wouldn't use VCam and an EFR9174 for Pro-GTR drag racing.   

[r32-25t]

I'm not saying bigger cams don't have their place, if want a 1000hp at the wheels then obviously you're going to use a fairly decent sized cam but then again at those levels response isn't at the forefront of your priorities. 

What im saying is so many people are fitting bigger cams in the pursuit of better down low power and improved response, perfect expample is If you have an engine that has cams that still make power at 8500 and turbos that roll over at 7000 how is bigger cams going to be a benefit?

My findings come from many cars I have worked on from 6L na v8, 2.0 4cly turbos and down to 1.3L 4cly na engines. Even rotarys with their port timing will do exactly the same thing 

[Lithium]

5 minutes ago, r32-25t said:

I'm not saying bigger cams don't have their place, if want a 1000hp at the wheels then obviously you're going to use a fairly decent sized cam but then again at those levels response isn't at the forefront of your priorities. 

What im saying is so many people are fitting bigger cams in the pursuit of better down low power and improved response, perfect expample is If you have an engine that has cams that still make power at 8500 and turbos that roll over at 7000 how is bigger cams going to be a benefit?

My findings come from many cars I have worked on from 6L na v8, 2.0 4cly turbos and down to 1.3L 4cly na engines. Even rotarys with their port timing will do exactly the same thing 

Exactly.  Sounds a bit like you're arguing with yourself and declaring yourself the winner  The setup needs to match the other parts, most would agree.    I'm not aware of anyone fitting larger cams for low down power, though improved response within the target rev range... perhaps.  

[r32-25t]

There are a few 

[No Crust Racing]

Take it back to the cam thread. 

I'll post in there next week when my setup is 4000rpm laggier for the extra 10 peak kW

[Lithium]

2 minutes ago, ActionDan said:

Take it back to the cam thread. 

I'll post in there next week when my setup is 4000rpm laggier for the extra 10 peak kW

OOPS!  Good call ActionDan, sorry Piggy.  If anything we should be talking about your low emissions cams and big laggy lightswitch turbo!

Yes, that'd be appreciated in the correct forum

 

[Piggaz]

Couldn't fit the emission friendly cam in this time round. It's all in its box in the garage. Tackle that later on.

Lightswitch, laggy, snappy, unresponsive, slow to react to throttle input single is a goer but ?.

[SimonR32]

4 hours ago, Piggaz said:

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? 

The Kelford split cams (182S) I had in were 10.8mm lift so the head had to be releaved already.

New ones are as follows "We’ve just run some numbers and we can take our L182-A 260° spec and turn it into a 260° advertised (measured at 0.1mm valve lift with lash set), 226° @ 1mm valve lift and would be .406” cam lift, coming out at 10.00mm valve lift on the intake and 9.95mm valve lift on the exhaust after lash. At the base circle we’d need to cut them to, to try and ease the re-shimming process, you’ll be right on our safety limits of velocity and getting close to our nose radius limit, it’d be an aggressive wee monster and something I think would be a much better fit for your setup given your historic results."

There was an option to also drop to a 262 advertised with a 222 at 1mm and drop valve lift to 9.7mm but decided against it as they recommended the other grind

Edited April 27, 2017 by SimonR32

[Piggaz]

How long until the results are in, Simon?

[SimonR32]

28 minutes ago, Piggaz said:

How long until the results are in, Simon?

It's ready to go, just needs a tune... Tuner has been on holidays for a few weeks so waiting until he gets back and into it

[Piggaz]

Sweeeeet

 

[Piggaz]

Double post ?

[No Crust Racing]

11 minutes ago, SimonR32 said:

It's ready to go, just needs a tune... Tuner has been on holidays for a few weeks so waiting until he gets back and into it

Race you! I dropped my modified Cam off yesterday. 

[Sub Boy32]

Are we there yet....are we there yet....are we there yet?!?!?

[Piggaz]

8 minutes ago, Sub Boy32 said:

Are we there yet....are we there yet....are we there yet?!?!?

Haven't heard anything. Not gonna be a pest and ask 4 times a day where they're upto. 

 

[Nismo 3.2ish]

Just be your normal self. be a pest ,  we need to know it is just not smoke and mirrors

[No Crust Racing]

The more times they answer the phone, the less time they have to work on cars in the shop.

[Lithium]

 

... sorry anyone who saw an update notification and had a precum....

Edited May 5, 2017 by Lithium

[Dose Pipe Sutututu]

On 2017-5-3 at 6:34 AM, Piggaz said:

Haven't heard anything. Not gonna be a pest and ask 4 times a day where they're upto. 

 

That's how a particular workshop tunes actually  (not the one your car is at).