3.2 RSR Hillclimb Engine Build

[waddy]

The build started a few months ago having been planned well before Covid struck, although further lockdowns have caused delays in getting parts. I have owned this late 3 litre SC engine since June 2001, but due to some issues with cleaning of the case I have not touched it since then and in fact bought another engine a few years later which I have raced for many years in various guises. I was going to have my existing engine upgraded from a 250 bhp twin plugged lump, with PMO 46mm carbs, 964 camshafts and JE high compression pistons by adding AT Power ITBs and DC60 camshafts to give the 280 bhp needed for my PCGB Speed Championship class. However I decided to embark on a new build as the old engine could do with a refresh after it's 6 seasons of both my son and I campaigning the car. The old Redtek engine will stay as a spare and perhaps get some much needed care next winter.

Engine specification will be:-

3.2 style engine case without oil sump cover.

Reground 3 litre crankshaft with 1st oversize bearings (it was standard, but would not pass the test)

964 Turbo oil pump

Carillo rods and bolts

Mahle 98mm barrels and RSR pistons

Turbo piston squirters

3.2 litre twin plug heads with porting

Complete new set of valves and 6 guides

Set of Schrick race springs and titanium retainers

DC 60 camshafts

AT Power shaftless throttle bodies with Emerald ECU

Here are a few pictures of the great work being done by Richard of CTR Developments.

 

[Ian Comerford]

Very nice Ian!

[waddy]

Thanks Ian!

[WP0ZZZ]

Wow, that's hard porn!

A couple of questions if you don't mind:

1. How hard are you going to rev it?

2. What compression ratio are you going to get with the new Mahles and rods?

[waddy]

The rev range for the DC60 camshaft is 4500 to 7500, but the rods and bolts are good for 8500. The limitation will be the rockers as we have stayed with standard at the moment with Schrick rocker sets at around £3k. 

The compression ratio is an interesting one with Mahle quoting 10.3 to 1. Richard calculates rather conservatively and tells me that none of the pistons he has used make the claimed compression, so it will be over 10 to 1, but not as much as with original RSR heads which have different volumes. The heads were machined to get as close as possible, but not so close that we will get clearance problems.

[WP0ZZZ]

9 hours ago, waddy said:

Schrick rocker sets at around £3k

crazy 😲

Do you have any particular preference for Schrick over Pauter rockers?

Schrick vs stock:

https://lnengineering.com/products/rocker-arms/single-billet-911-rocker-std-ratio-dlc-coated-swivel-feet-adj-not-inc.html

9 hours ago, waddy said:

so it will be over 10 to 1

With 10:1 and twin plugs, will you get into knock problems when tuning the advance?

[waddy]

No, I won't be fitting either at the moment although Richard likes Schrick!

I don't think so, but will leave that to the engine builder and tuners. Have you had any experience of issues?

[WP0ZZZ]

5 hours ago, waddy said:

Have you had any experience of issues?

I don't have any personal experience with those engines. But I'm planning to start modifying my stock 3.0 at some point next year 😃

[waddy]

10 hours ago, WP0ZZZ said:

I don't have any personal experience with those engines. But I'm planning to start modifying my stock 3.0 at some point next year 😃

What do you plan to do to your engine?😀

[waddy]

Further progress made with engine. Clewett cam sensor fitted, camshafts timed, new set of stainless steel baffle plates arrived very quickly from Matt and fitted and case buttoned up. Now probably going with 964 lower cam covers with twin plug holes and Kroon engine wiring harness. Awaiting race headers from Turbo Thomas by the end of the month hopefully.

[waddy]

Further progress made, waiting for social freedom before getting engine installed into car and then off for rolling road session!

 

[Ian Comerford]

Lovely!

[waddy]

Thanks Ian.

[World Citizen]

That's one of the cleanest 911 engine builds I've seen 😎 

[hetherc]

Looking really good Ian! My engine has done just over 150K now and thank goodness continues to run beautifully. 🤞🤞🤞as I dread having to go to all this expense: Pulled it out of its Carcoon yesterday and had a quick blast up Cheddar Gorge (en route to buying essential milk of course). Will have to try and get along to watch you race this year. Good luck with the new engine. 

[waddy]

13 hours ago, World Citizen said:

That's one of the cleanest 911 engine builds I've seen 😎 

Thanks WC I will pass that on to Richard!

[waddy]

49 minutes ago, hetherc said:

Looking really good Ian! My engine has done just over 150K now and thank goodness continues to run beautifully. 🤞🤞🤞as I dread having to go to all this expense: Pulled it out of its Carcoon yesterday and had a quick blast up Cheddar Gorge (en route to buying essential milk of course). Will have to try and get along to watch you race this year. Good luck with the new engine. 

Thanks Clive it is taking a long time due to various lockdowns, but hopefully we will get it in the car before May and the first race 🤞🤞. The costs are fair, but should be worth it. The weather is lovely now, I am sure the car appreciated coming out of hibernation almost as much as you did😄. It would be good to see you at one of the events, I think the last time we met was Silverstone Classic. Thanks!

[waddy]

Engine fully completed and running and on the button with 280 bhp and 247 ft lbs to meet class limit. Runs well on road with DC60 camshaft which is slightly lumpy at tickover, but not a problem. Turbo Thomas 42mm race headers work well. Getting ready for first meeting of the year at Shelsley Walsh next Sunday with spectators now allowed back I believe.

[Ian Comerford]

Lovely Ian ,bet you can’t wait!

[waddy]

Indeed Ian, it has been a long time since 2019!

[Nige]

Fancy building something similar for me 

[waddy]

I may have the knowledge now Nige, not sure that I have the energy! I do have a spare set of AT throttle bodies, but they are more suited to 3 litre 39mm heads.