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Posted

The old crank has been checked and measures up to spec.  Neil thinks it's worth £1500 based on a new price of £4800 + vat- if any one is interested please give me a shout.  

Old rods available too, although they will need to be refurbished. Price TBC.

New rockers and shafts arrived - old rockers I need to check if they can be refurbed (already done once so maybe not)

New GT3 oil pump arrived (replaces a genuine 3.2 item with <30k miles on it, available if anyone interested - ping me a PM)

Neil's straight steel cut intermediate shaft gears arrived - old alloy gears are reusable I'm reliably informed (PM if interested) 

Still waiting on new crank, rods etc to return from balancers.  

Re new cams from WK, Neil didnt think the piston crowns would need machining even though the cams are timed at 5mm. A dry run build will prove either way.  Used DC20s also available and in good shape.

Thoughts turning to the intake - still need to confirm if ITBs are needed for 'day 1' or whether they can be retrospectively fitted. Neil's shaftless items are still technically proof of concept and yet to be seen in the wild.  Alternatively Jenveys are a tried and tested solution, although Neil still not happy wth the amount of linkages used and potential to fall out of tune hence his own design (prices TBC).  PMOs another alternative but with a sub optimal design (would I feel the difference ?).

Usage of a common plenum (993) over the ITBs still being discussed (a la Rothsport). The standard 993 intake crossover tubes provide everything needed (inc resonance flap, vacuum, solenoid, etc) for a not unreasonable £490 inc vat brand new from Rosepassion; Neil may be able to knock an alternative up but price would be similar, so maybe best to go with a new Porsche item (The  plastic intake stacks were about £450).  In addition, the 993 airbox arrangement could also be used (£200 for a new one, £250 for a "motorsound" item).  

Ultimately I'm still waiting on a price from Neil for his ITBs (via AT Power who make the shaftless bodies) - if unreasonable, I will leave for now and maybe approach 9m for a second opinion as their ITBs are Jenvey based so assume no linkage issues are apparent.

Finally, valve springs - upon removal, we found none of the pairs of Smart Racing Valve springs removed could be depressed by more than 1-2mm between index finger and thumb. The new Schrick springs Neil had in comparison would give by a good 5mm.  Still needs to be confirmed, however potential for some lost hp caused by overly stiff springs according to Neil and maybe increased rocker pad wear.

Posted

I wonder if Fenn Lane have got their ITBs up and running yet? I would assume the price will be very competitive and IIRC Chris told me the standard Porsche linkage already in the car is adapted.

Posted
15 hours ago, SP72 said:

Finally, valve springs - upon removal, we found none of the pairs of Smart Racing Valve springs removed could be depressed by more than 1-2mm between index finger and thumb. The new Schrick springs Neil had in comparison would give by a good 5mm.  Still needs to be confirmed, however potential for some lost hp caused by overly stiff springs according to Neil and maybe increased rocker pad wear.

Hi Shirish, were these part of the your original build specification, do you think you may have any redress with Smart Racing?

For all future engine builders, checking the compression on all values, in fact checking the tolerance on all third party items should be mandatory me thinks.

 

Posted

I also feel your pain Shirish after what happened to me last year. I very nearly sold the car as I was so disappointed and was without the LE from April to January!

Fortunately my 2nd rebuild in a year was done by Andy at SCS so I am confident all is good, the things he found, you just think why! just wish I had gone to him in the first place.

There is a lot of so called engine builders out there which should not be in business

Regards  kev

Posted
1 hour ago, Beaky said:

Hi Shirish, were these part of the your original build specification, do you think you may have any redress with Smart Racing?

For all future engine builders, checking the compression on all values, in fact checking the tolerance on all third party items should be mandatory me thinks.

 

Beaks, they were fitted during R1, yes - you'd think the engine builder would have picked on them being too stiff, however they were deemed fine at the time.  SRP stopped making products a while ago.

Anyway, no point looking back - add to lessons learnt as you say and go again!

Posted
1 hour ago, kevinkjse said:

I also feel your pain Shirish after what happened to me last year. I very nearly sold the car as I was so disappointed and was without the LE from April to January!

 

Fortunately my 2nd rebuild in a year was done by Andy at SCS so I am confident all is good, the things he found, you just think why! just wish I had gone to him in the first place.

 

There is a lot of so called engine builders out there which should not be in business

 

Regards  kev

 

Thanks Kev, yes I agree, the term 'engine builder' needs qualifying somewhat.  Glad you're now sorted, it's an expensive business when it goes wrong.

From the level of detail Neil has provided during his inspection I'm feeling confident I've made the right choice in using him. 

  • 4 weeks later...
Posted

Not toooo much action recently as NB was in the US, however a quick update on parts/tasks completed:

06/02/2017 - Remove engine and gearbox - split engine from gearbox - store box and put car into storage. 3.75h
07/02/2017 - Fit engine to stand Start to strip and inspect, remove intake / exhaust systems. Remove cam covers remove rockers and note damage on faces, remove cams and remove carriers, strip off heads note one head fitted with no head nut support washers.
08/02/2017 - Strip crank cases and bottom end for inspection/repair / Start to clean parts, build up new crank with gears.
09/02/2017 - Strip heads for inspection Check Guides and clean, remove studs check head heights.
10/02/2017 - Strip case studs to check deck heights as 4/5/6 have had valve contact and the liners are spaced @ 0.75 while the other side is @ 0.50 ? clean and store parts, modify crank case for new GT3 oil pump.

Part Number/Activity - Description
996.107.007.94 - Oil Pump Engine GT3
NBE10211180 -  Intermediate gear Straight Cut 911 Crank
NBE10501380 -  Intermediate gear Straight Cut [Big Gear] 
930.105.419.51 -  Valve Exhaust 911 3.0/3.2 x6
930.105.409.13 - Valve Inlet 911 3.0/3.2 x6
CRANK CHECK BALANCE FLAT 6 CYL
MODIFY FLYWHEEL LIGHTEN 1
BALANCE FLYWHEEL RACE SPEC
MODIFY FRONT PULLEY TO FIT CRANK
NBE.VG.STD.000 - Valve Guide 911 STD x12
VG/RR/PORSCHE - Valve Guide Remove & Replace x12
VS/RC/PORSCHE/3A - Valve Seat Recut to Porsche 3 Angle Specification

 

Posted

Making progress! It will get there Shirish. Looking forward to more updates...:D

Posted

Hoping Neil has some pics of this, however bottom end is now together, incorporating the Gt3 crank, GT3 oil pump, custom Pauter rods, and Neil's own steel straight cut IS gears which i'm told will give it quite an old school MFI-ish sound, whilst being more robust than the standard ally items.

Decision taken to go with Neil's ITBs which will bolt direct to the heads, so no adaptors will be needed which saves a few hundred quid.  I wasn't 100% sure on ITB's, however, the decision was based on their much improved throttle control and ability to deal with intake reversion, which leads to the part throttle bunny hopping i've experienced ever since R1 was undertaken.  On their own, they don't add much/any power/torque, and if you follow Colin/9m, you'll know he only considers them as required for cars needing power of 7k. 

Rothsports engines use a 993 intake plenum (or GT3 for 3.6/3.8/4.0 builds ) on top of the ITBs to enhance low-midrange torque and throttle response, so the next expenditure will focus on the 993 resonance valve flaps, solenoid and air intake.

Still unsure what we're doing re the air filter arrangement - simplest way is to use a 993 setup, however the Rothsport setup is more efficient, being a t-piece straight off the plenum.  Work in progress

In addition, Neil's unsure if different valve springs are needed - testing needed of the existing springs, and also a decision needed on whether to keep the Ti retainers or revert to steel.

Oh, and i've just asked Neil which oil i should use .... :)

18 minutes ago, Dr Rock said:

Making progress! It will get there Shirish. Looking forward to more updates...:D

Yes indeed - no rush from my side at all Fraser, have left him to it.

Posted

Some pics here of Neil's ITBs, still unsure how long/tall the runners will be so some calculation needed. Bearing in mind we wont use the trumpets as the 993 plenum will sit on top. Think mine will be the first set on the road.

1eb68b88a2b0e19b77ad5263ee9f1699.jpg

e7e417d0b8238ca09bcb9c87bf6c827e.jpg


Neil's favoured linkage below:
b977b0c5d9d304513fa4c731d984be22.jpg

Single pic of the custom Pauter rod being used. Unsure of rod length, looking to confirm. Chosen over Carillo purely down to cost and availability.

424df8a6a5d6155de1a16ee65f014a3b.jpg

Posted (edited)
On 3/19/2017 at 0:24 AM, SP72 said:

Oh, and i've just asked Neil which oil i should use .... :)

 

You started it and was it extra virgin olive oil from Cyprus............................................lol

Edited by Beaky
Posted

Those ITBs look very pretty! Much prettier than my PMOs. The linkage looks good too. With all the other upgrades it's going to be a monster when it's done.

Posted
You started it and was it extra virgin olive oil from Cyprus............................................lol

In all seriousness, I've had to give it some consideration especially with the amount of rocker wear shown. This should be 100% related to the blocked spray bar, however I'll use whatever oil he uses after run in completes on his engine dyno
Posted
Those ITBs look very pretty! Much prettier than my PMOs. The linkage looks good too. With all the other upgrades it's going to be a monster when it's done.

Bear in mind that's not my engine in the pics above, however I'm not expecting them to look much different.

Yes, the linkage was one of Neil's primary concerns with Jenveys, saying the number of parts involved used can cause the throttles to go out of balance too frequently. Further supported by Rothsport who also use Jenveys but who have redesigned the linkages too, so appears a common issue.
Posted
2 minutes ago, SP72 said:

Yes, the linkage was one of Neil's primary concerns with Jenveys, saying the number of parts involved used can cause the throttles to go out of balance too frequently. Further supported by Rothsport who also use Jenveys but who have redesigned the linkages too, so appears a common issue.

I think the linkage on PMO ITBs is a simpler setup than Jenvey. It's still possible for them to go out of balance, but not as easily as the Jenvey setup.

Posted

Yes I read that too. I contemplated PMOs but have been swayed by Neil advising his shaftless ITBs permit using smaller diameter bores than traditional ITBs, resulting in better midrange. These are 45mm, versus the 48mm Jenvey that Rothsport recommend

Some more bumph:
"These Direct-to-Head Throttle Bodies have been designed to be used in applications where a conventional Throttle Body would be too large for the required mass air flow and helps to maintain your flow velocity resulting in an increase in volumetric efficiency. This is a direct mounting to the cylinder head so no additional manifold is required. These throttle bodies feature 'shaftless' and knife-edged butterflies for improved airflow & performance and with the throttle blade very close to the inlet valve the engine response is significantly improved and offers superior idle control over other individual throttle bodies"

Posted

They do look awesome and a better solution than PMOs or Jenveys. I'm very jealous! I went with 40mm on mine as it was never going to be a 300+bhp monster and I was more concerned about a good midrange than a screaming top end with a lumpy idle.

Posted

Easy to go with a 'bigger is better' mentality so I admire your restraint! Your engine spec sounds peachy, perfect for a road car.

Posted
6 hours ago, SP72 said:


In all seriousness, I've had to give it some consideration especially with the amount of rocker wear shown. This should be 100% related to the blocked spray bar, however I'll use whatever oil he uses after run in completes on his engine dyno

So are you saying is the extra, extra virgin oil with a hint of Neil..........................lol.

As a known guru when it comes to engine building it'll be interesting to know what he recommends

  • 5 weeks later...
Posted

Coming along ...

IMG_1994.JPG

I spy some extra valve relief on the piston that's been fitted,

New chain too

Posted

Nice looking engine..what is interesting for me  is...the engine case trough bolts  from factory go right to left but here they go left to right.

I like it because i do it exactly the same way....and this is the first time i see it done by some other mechanic..:ani_clapping:

 

Ivan

Posted
2 hours ago, proporsche said:

Nice looking engine..what is interesting for me  is...the engine case trough bolts  from factory go right to left but here they go left to right.

I like it because i do it exactly the same way....and this is the first time i see it done by some other mechanic..:ani_clapping:

Looks the same as mine...?

 

Posted

Why would you think of ditching the Ti retainers?  For 30 years that has been a known and tested upgrade for big valve 911 engines looking for some safety margin in the event of over rev. 

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