Supertech Solid Lifter Conversion Kit - Experience?

[Unzipped Composites]

Hey guys,

I'm looking for anyone that has used the Supertech solid lifter conversion kit and what your experience was. I'm sure it's a good quality kit, but I'd like to know if there were any unforeseen parts of the process, for example, did you need valve seat inserts for the oversized valves?

What are the camshaft options for an RB25 with solid lifters, will aftermarket solid cams for the Neo work or are there still other differences there?

Application is for a full time race engine; high CR (~10:1) with around 600rwhp. 

Just looking into this at the moment because after spending the last year trying to source a replacement virgin Neo head for my build, I'm desperate enough to get the build going again that I'm considering just running a vanilla RB25 head and converting it to solid lifters. I would prefer to not use oversize valves, but nobody except Ferrea seem to do that. 

[GTSBoy]

Now is the time to talk to someone like Knight engines here in Adelaide about doing a proper job on the head, along with some nice Kiwi cams to go with the lifter conversion and the bigger valves. If you're going to start working on a head at all, you might as well do it properly. All the seats will come out, all the guides will come out. The head will be ported to within an inch of perfection and it will make 600rwHP on about 80% of the boost you would need without it.

[Unzipped Composites]

Yeh, I can appreciate that and at the end of the day I agree - but after years and years of getting stung by 'reputable' workshops doing half assed jobs (including the 'best-in-the-business' head shop here that thought taking a die grinder to my buckets was part of a standard clean-up on my virgin Neo head) I just have serious trust issues. I have my machinist/engine builder that I trust, so I won't be engaging any third parties.

Unfortunately my machinists machine for doing valve seats isn't totally suited to doing inserts. He can do the rest, and he said he CAN do the inserts but there's a chance the machine messes it up and then that head is wrecked as well, so we are hoping to avoid doing inserts. Guides etc is not a problem. 

This car is being built for a purpose, and that is to run a 61 around Wanneroo Raceway while toeing the line with Clubsprint class time attack regs. That is fast, but it's not hugely ambitious. A ~500hp full street trim RWD Skyline can do it, so I know I don't need to go crazy with everything and I can afford to draw the line at a relatively basic build. Realistically, I don't my heart set on cracking 600hp, I don't care if it falls a little bit short or we need to curb it  that target is just what I am using to select the parts for the build.

Really the Supertech kit is overkill for the goals of this car, and I'm not 100% sold on it, but I also dont want to use hydraulic lifters and cams so I'm somewhat restricted with my options. Wanneroo Raceway with 4.11 final drive means I am going to be living high up in the rev range, and hydraulic valvetrain just doesn't feel like a good option. Really a stock Neo head with springs/retainers and cams, and new OEM valves is all I need/want, but these days that Neo head is either impossible to find or will cost more than the Supertech kit and then still need to factor in the valvetrain costs. It's easy to get carried away and do it all with the 'do it once do it right mentality' which I do very much agree with, but at the same time the more this build costs the further away the finish line is and I do want to get it on the track and start developing the products I have in the pipeline for it, so I'm trying very hard to keep my eye on the reason I'm building this car.

 

[Komdotkom]

+1 for Tony at Knight Engines, he built my RB a few years ago and it's a ripper. He's a one man show though so lead times are long, but you know the apprentice hasn't done your head so it's worth the wait. I totally get your trust issues, there's very few people I'll pay to work on my car.

With respect to the lifters, cam profiles won't change much from a 26 or Neo, you'll just have to make sure the installed height of the bucket is correct. I'm assuming it's a shim under bucket conversion? Have you looked at a shimless bucket setup to reduce the mass of the valvetrain? 

The kiwi's have some great cam profiles and quality springs (as opposed to Jap tuner 'shopping list' springs) which will be a decent combo. The guys at Kelfords are happy to discuss what you are trying to achieve - give them a call they have probably worked with a customer on a vehicle that's had the Super Tech conversion. 

 

[Unzipped Composites]

3 hours ago, Komdotkom said:

+1 for Tony at Knight Engines, he built my RB a few years ago and it's a ripper. He's a one man show though so lead times are long, but you know the apprentice hasn't done your head so it's worth the wait. I totally get your trust issues, there's very few people I'll pay to work on my car.

With respect to the lifters, cam profiles won't change much from a 26 or Neo, you'll just have to make sure the installed height of the bucket is correct. I'm assuming it's a shim under bucket conversion? Have you looked at a shimless bucket setup to reduce the mass of the valvetrain? 

The kiwi's have some great cam profiles and quality springs (as opposed to Jap tuner 'shopping list' springs) which will be a decent combo. The guys at Kelfords are happy to discuss what you are trying to achieve - give them a call they have probably worked with a customer on a vehicle that's had the Super Tech conversion. 

 

 

Yes, Supertech kit is shim-under-bucket. Have spoken about going shimless, but machinist talked me out of it because of the wear issues. He convinced me there's nothing wrong with shims provided everything is setup properly. 

My intent is definitely to use Kelford camshafts, so I will get in touch and have a chat to them. In all honesty, the more I read the more I'm wondering if converting to solid is worth it. I don't plan on hugely aggressive cams, I'm prioritising response over peak power. Turbo will probably be a G25-660, so I'm not trying to spin the engine to 9000rpm either. Stockish rev limit, moderate cam profiles - is solid really worth the trouble? 

On the other hand, my problem isn't the money, I actually think the Supertech conversion kit is quite good value considering I'll be doing all of the included components minus the lifters even if I stay hydraulic - costs wise it isn't much different. My problem is that I don't want oversized valves, and Supertech don't have a standard size option. I would much prefer to use Ferrea standard size valves and Ferrea springs.

What about the Tomei solid lifters? They only do the lifters not a full kit, so is the conversion just a case of solid lifters and solid cams, and I can still use my choice of valves and springs? Or would the valves and springs need to suit the solid conversion? 

[r32-25t]

The main reason for going with shimless is of you intend of using 2 step or any other form of ignition cut such as anti lag or flat shift where you cut the spark as it can tend to float the valve slightly even with the best springs in the world 

[Unzipped Composites]

Yeh no intent to use any of that.

[Dose Pipe Sutututu]

And this is why you don't want to go shimless - I was going to do this on a bare NEO head for sale, but the thought of it put me off. FWIW, I've found another NEO motor

[Unzipped Composites]

Yeh you're a lucky bugger  In the year I've been looking, I've seen 3 Neo heads for sale...

 

First one was recently built with 3000km's on it since build; Kelford cams, oversized valves (would want to check this has been done properly), VCT deleted (not ideal), hand ported by the owner (not ideal) - they wanted $12,000, and were not happy for the purchase to be subject to my machinists approval (alarm bells).

Second one was completely stock, but had been cooked and was warped 25 thou. Machinist said no, too hard to straighten without it cracking or warping sideways.

Third one is apparently virgin and completely stock, and still available as far as I know - but he wants $3500 for it. Would still need to buy new valves, springs, retainers, guides, etc. etc. So when the Supertech conversion kit costs $3300, and would result in the complete head ready to go, it starts to feel like really poor value to just buy the stock Neo head for the same money.

 

 

 

 

[Unzipped Composites]

Also, hope your head shop machines heads better than they spell: "BASE CIRCLKE DIAMETOR..."  😆

[Dose Pipe Sutututu]

6 minutes ago, Unzipped Composites said:

Also, hope your head shop machines heads better than they spell: "BASE CIRCLKE DIAMETOR..."  😆

LOL... well thank fk I didn't go ahead with that!