RB25DET with solid lifters - which cams ?

[TomSky33]

Hello from Germany,

 

i build my RB25DET Series 2 -> Target 600hp

i have now ordered solid lifters from Tomei for the cylinder head and will replace the original hydraulic lifters. Which cams can you recommend ?

It is only a street car.... Maybe i order a Garrett GTW38 or something like that.

 

and what is with the VCT ? is it blocked with the solid lifters ?

 

Attention is a RB25DET with solid lifters!

 

Thank you for your help

 

 

[GTSBoy]

Lifters (solid vs hydro) do not affect VCT.

For cams, just contact Kelford in New Zealand and tell them what you want to do with the engine and that it is a solid converted 25. They'll know what to give you.

FWIW... you can probably use any cam with either hydro or solids at that power level. By "any cam" I mean, there probably isn't a particular reason for the profile to be much different between the two.

[TomSky33]

That was a really fast reply! Thank you very much. i will contact kelford.

 

Have a great day

[Dose Pipe Sutututu]

FWIW I run Kelford 264/272 9.6mm and still retain VCT.

VCT is great, enables all that low end torque to help bring on the turbo earlier compared to a non VCT motor.

[TomSky33]

Okay that sounds great!

How much hp do you drive and with which turbo ?

 

[TurboTapin]

22 hours ago, GTSBoy said:

Lifters (solid vs hydro) do not affect VCT.

For cams, just contact Kelford in New Zealand and tell them what you want to do with the engine and that it is a solid converted 25. They'll know what to give you.

FWIW... you can probably use any cam with either hydro or solids at that power level. By "any cam" I mean, there probably isn't a particular reason for the profile to be much different between the two.

 

14 hours ago, Dose Pipe Sutututu said:

FWIW I run Kelford 264/272 9.6mm and still retain VCT.

VCT is great, enables all that low end torque to help bring on the turbo earlier compared to a non VCT motor.

I also intend to go solid lifter at some point with my S1 RB25. I asked Kelford if I could use my S1 VCT 264/272 (246-A2) cams and they said no. They recommended that I use their 244 NEO cams. 

[TomSky33]

18 minutes ago, TurboTapin said:

 

I also intend to go solid lifter at some point with my S1 RB25. I asked Kelford if I could use my S1 VCT 264/272 (246-A2) cams and they said no. They recommended that I use their 244 NEO cams. 

when kelford answer me i will write it here. it depends on what kind of setup you want to ride.. i will take a Garrett GTW38 and 600hp for the street. and then they choose the cams...

[Dose Pipe Sutututu]

4 hours ago, TomSky33 said:

Okay that sounds great!

How much hp do you drive and with which turbo ?

 

Made 439kW at the rear hubs at 1.8bar of boost tapering down to 1.7bar on E85. Has a (now ancient) Garrett GTX3576 Gen 2 with a 1.01 divided housing.

I just leave it on max boost all day lol.. car sees more track time than the street anyway.

[TurboTapin]

2 hours ago, TomSky33 said:

when kelford answer me i will write it here. it depends on what kind of setup you want to ride.. i will take a Garrett GTW38 and 600hp for the street. and then they choose the cams...

My comment was aimed at the mention of possibly using hydraulic lifter based cams with solid lifters. I make a lot more then 600hp. It has nothing to do with power. Cam/Lobe profiles differ between hydraulic and solid lifters. Kelford stated their hydro lifter cams cannot be used with solid lifters. 

Kelford will probably recommend their 244-A2 cams for your goals. 

Cheers. 

Edited September 11, 2024 by TurboTapin

[TomSky33]

1 hour ago, TurboTapin said:

My comment was aimed at the mention of possibly using hydraulic lifter based cams with solid lifters. I make a lot more then 600hp. It has nothing to do with power. Cam/Lobe profiles differ between hydraulic and solid lifters. Kelford stated their hydro lifter cams cannot be used with solid lifters. 

Kelford will probably recommend their 244-A2 cams for your goals. 

Cheers. 

Okay, I'm curious to see what they'll say. Do you also ride these cams ? or which ones do you ride ?

 

3 hours ago, Dose Pipe Sutututu said:

Made 439kW at the rear hubs at 1.8bar of boost tapering down to 1.7bar on E85. Has a (now ancient) Garrett GTX3576 Gen 2 with a 1.01 divided housing.

I just leave it on max boost all day lol.. car sees more track time than the street anyway.

 

I'll have to think carefully about the turbo and manifold. The police in Germany are very strict

[Dose Pipe Sutututu]

6 hours ago, TomSky33 said:

 

I'll have to think carefully about the turbo and manifold. The police in Germany are very strict

Same as Australia, some police officers are strict and some are lenient and don't seem to mind the modifications, provided they are semi legal.

[Kinkstaah]

Germany is _very_ strict. Think along the lines of Mandatory full EPA every year.

[Dose Pipe Sutututu]

4 minutes ago, Kinkstaah said:

Germany is _very_ strict. Think along the lines of Mandatory full EPA every year.

Bolt up stock cat, run lazy timing on E85, should be fine yah? Lol.

[Kinkstaah]

I'm actually surprised he's considering running an aftermarket turbo, because the fact that it's not a stock turbo is deregister the car territory!

I would think Germany is the prime market for Hypergear highflows and ported stock manifolds, Nistune, Highflowed OEM injectors, super improved, ducted SMIC's and the like.

(or maybe it's not quite that bad)

[GTSBoy]

24 minutes ago, Dose Pipe Sutututu said:

Bolt up stock cat, run lazy timing on E85, should be fine yah? Lol.

It's not just an emissions test. Think of it like a full pits inspection with need to demonstrate engineering for any and all mods every time.

[GTSBoy]

20 minutes ago, Kinkstaah said:

I would think Germany is the prime market for Hypergear highflows and ported stock manifolds, Nistune, Highflowed OEM injectors, super improved, ducted SMIC's and the like.

If the place was full of Skylines, then yeah. But there's not very many of them.

[TomSky33]

If you have a nice TÜV inspector you can get everything registered... well, almost anything. But it's quite expensive in Germany. As soon as something is wrong, the police tow your car away and it gets really expensive.

Almost all Skyline drive Top Mount... at least if you want to drive performance. The market for Japanese cars in Germany is not really big.

Kelford said 244-A's or 244-A2's.... I will probably take the 244-A2.

 

[TurboTapin]

I now seem to be limited in power due to my rev limit/hydraulic lifters in my built RB25. I'm looking into converting over to Tomei solid lifters.

Question for anyone that has done the conversion. I was always under the impression that when using the Tomei solid lifter conversion, you would also require new valves (Longer or shorter stems, I can't remember which). 

I don't know where I got this idea, as so far I see no mention of this in any of the Tomei documentation. It just states I need the Tomei solid buckets, solid lifter cams and upgraded springs. As my head is already built, all I would need is another set of 1000$ Kelford cams, 500$ buckets and about 4H hours of my time installing and I'm off to the races!?!? There's no way it's that simple, I must be missing something? 

Edited 5 hours ago by TurboTapin

[GTSBoy]

I always wondered how you were supposed to buy a set of 24 buckets and somehow magically have every single one of them yield exactly the desired clearance.

I would have thought you'd need to assemble a cam with either 12 "sample" or "example" buckets of known top thickness (or a single such sample/example 12 times over!!) measure clearances at every valve, and then do the usual math to work out what the actual "shimness" of each bucket needed to be, before buying the required buckets to make up he thicknesses that you didn't have on hand.

[TurboTapin]

31 minutes ago, GTSBoy said:

I always wondered how you were supposed to buy a set of 24 buckets and somehow magically have every single one of them yield exactly the desired clearance.

I would have thought you'd need to assemble a cam with either 12 "sample" or "example" buckets of known top thickness (or a single such sample/example 12 times over!!) measure clearances at every valve, and then do the usual math to work out what the actual "shimness" of each bucket needed to be, before buying the required buckets to make up he thicknesses that you didn't have on hand.

They are under bucket shims. Tomei provides a test shim kit and then any measurement of shim required.