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Re-ground cams


Neil-NA

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Anybody had any experience of re-ground cams?

 

Just looking for some UK based companys that will do it to a set of NA cams, i know TTC in the states do them but by the time i have shipped my cams there, in exchange for the ones they do, got them sent back and maybe import duty and tax on top i'm looking at over 1K, surely it will be cheaper to get them done here.

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They end up with a smaller base circle and you will probably have to make custom shims. Get one ground on a billet. Much more expensive, but infinitely better. Piper Cams, Kent Cams or Cat Cams can all do this. They will need a sample cam as a pattern. Only issue may be cutting the disi drive gear tooth pattern. Very possible, but adds to cost. All the above can re grind your cams, too, but they may need re hardening with risk of them bending.

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Not too sure how TTC do it, im sure they use stock cams as they need exchange cams. I'm guessing custom made cams are going to run into the thousands,which i dont think is worth it on the NA for the power i'm after.

 

Think i need to think about this a wee bit more :(

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Custom ones on blank billets will be about £500 / £600 a piece. The only ways to regrind a used cam with higher lift are to reduce the base circle diameter, needing much thicker shims, or to weld the cams up and regrind, which AFAIK, is only possible on steel cams, not chilled cast iron as the stock ones are. Reground cams can be very iffy, depends how well they are done, and how the heat treat is then done. I would choose a UK firm over a US one any day.

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Custom ones on blank billets will be about £500 / £600 a piece. The only ways to regrind a used cam with higher lift are to reduce the base circle diameter, needing much thicker shims, or to weld the cams up and regrind, which AFAIK, is only possible on steel cams, not chilled cast iron as the stock ones are. Reground cams can be very iffy, depends how well they are done, and how the heat treat is then done. I would choose a UK firm over a US one any day.

 

Maybe they get away with the hardness issue on the base circle because on an engine with solid tappets there is actuall no contact on the base circle? Only the profile and ramps.

 

Reducing the base circle and increasing the lift within an existing profile is ging to limit you to roughly the same duration so your valvetrain loads are going to increase significantly, which means you will have poorly matches springs and will probably get excessive wear on an already compromised cam (hardness wise).

 

Sounds like a bad idea to me.

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It's trivial to add lift by re grinding, adding duration whilst keeping a sensible ramp and lobe form is a lot harder, and it's in attempting this compromises occur. The late professor Blair of Belfast University and his associates recently published several articles on cam lobe science. it was a bit too maths intensive for me but they explained the issues with regrinding to achieve more lift and duration quite well.

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Just got the following reply -

 

Hi Neil,

 

How are you today? Thank for writing. Our 2jzge cams are impeccable. Unlike other companies, we don't regrind the cams. Regrinding removes portions of the base circle and doesn't address the lobe itself. We tackle the real problem , the lobes. We use a hardwelding process, that after we're done, is harder than the original nodular iron camshaft material. We hardweld the lobed, then profile them to the correct lift and duration.

 

On performance, they can not be beat. Our 2zge cams have made as much as 1045rwhp on a stock distributor in a turbo application, and a few guys are now using them in high compression NA applications. The real headlines are what the cams do for your midrange and high rpm performance. The stock cams are meant for a passenger car's smooth running, and tend to drop off at around 4500rpm. Our cams are designed to pull and pull, all the way to redline.

 

On cores, we can source cores here locally. It's much easier than having them sent from the UK. The core cost is $300, but it's money well spent as you won't have a car that's down in the time it will take us to manufacture your camshafts. After the new cams are in, simply return your old cams to us here, and we will reimburse your core charge. We make it really simple all around.

 

 

Thanks!

 

Eric Lemoine

Owner/CEO, TTC Performance Products

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I personally think it's worth a crack. they would need to be re shimmed at the garage during fitting (obviously) and I think its worth sourcing cams ourselves.

GROUP BUY!!!!!!!!!! +1 im in.

 

pics of finished cams AFTER process. they basically re con them as well. ooooo clean mmmmmmmmm

 

sourced these pics from supra forums, u can see the dredded dizzy gear:

 

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Edited by Noz (see edit history)
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Sorry to pester you Chris but what do you make of the reply I got?

 

Sounds like a typical American salesman at play :) You'd just have to bite the bullet and buy a pair and try them. I can put them on the Cam Doctor machine and get a full print out of specs and tolerances for a small fee. What are you using ECU wise to map it if you change cams?

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my local garage semi-tuner (does racing but im not fully aware how good his skills are) reckons a set of vernier pulleys would do the job for tuning but i did read ecu management would be a more reliable option.

 

whats involved with your cam doctor machine? im hoping to buy an NA-T kit soon and would like to get some of these cams and get them fitted at the same time? do you do the check after high lift?

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Sounds like a typical American salesman at play :) You'd just have to bite the bullet and buy a pair and try them. I can put them on the Cam Doctor machine and get a full print out of specs and tolerances for a small fee. What are you using ECU wise to map it if you change cams?

 

Ryan G will be fitting and mapping an emanage ultimate, tbh I'm only wanting 250 HP. I'm currently at 232.6.HP, so new exhast manifold and all the above I'm hoping will gain me the 18 hp.

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As Martin said I already have an OBX mani and its pants.

 

I have tinkered more than most with N/A's and the best Fannymould I found is the Autobahn88, you just need to check the flange face is true and the ports may need a little grinding to match, I bought mine new for £60 and got £40 back for complaining.

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