Building an engine for Trackday use - Opinions please
09-04-2018, 07:09 AM
#1
Instructor
Thread Starter
Building an engine for Trackday use - Opinions please
I am intending on rebuilding my engine this winter, 996 3.4 C2, the car is predominately used for trackdays, which I drive to. The car is driven, but with mechanically sympathy and does not spend any of its time bouncing off the limiter, I change up at 6k. – I mention this as it may factor into component choice and where the power band sits.
During the rebuild I want to engineer out as many of the common faults as possible and extract a little more power, however budget is not unlimited! – I am obviously discussing this with my engine builder but I would welcome the opinion of those that have walked this path and can comment on what they feel is worthwhile, what is not, and if I am missing anything or creating issues for myself.
Although fluid current thinking is..,
Oversize (3.7), closed deck, Nikasil Liners, forged pistons, newest design IMS.
Con Rods, is it worth paying for the likes of Carrillo, or are standard con-rods with uprated ARP bolts adequate? – What benefit would Carrillo bring how often to the standard rods fail?
Standard heads, is there anything else available? Are there any know fixes for the cracking issue? – Input welcome
Standard Cams, is there anything else available, is it a worthwhile upgrade? – Input welcome
Porsche Motorsport Air/Oil separator, worthwhile over the standard item?
Lightweight Flywheel & Sprung clutch, balanced to crank. – Thoughts on this? I know there are concerns about the crank, however the 3 different builders I have spoken to see nothing but benefits.
996 X51 Intake & Runners
997 X51 Exhaust manifold/headers (with Ti studs)
IPD Competition 83mm Plenum & 997 GT3 83mm Throttle body
BMC Panel Filter in standard airbox.
FVD Motorsport sump with X51 Baffle
Car will be remapped when complete.
Car already runs LTT, center rad and will get the water pump, chains, guides, bearings, seals etc etc done as part of the rebuild.
I know oil surge may still be an issue, pressure and tappet carrier, but I do not think I can stretch to rectifying these, if even reliable fixes exist, but again comments are welcome on these issues.
What am I missing?
Thanks
During the rebuild I want to engineer out as many of the common faults as possible and extract a little more power, however budget is not unlimited! – I am obviously discussing this with my engine builder but I would welcome the opinion of those that have walked this path and can comment on what they feel is worthwhile, what is not, and if I am missing anything or creating issues for myself.
Although fluid current thinking is..,
Oversize (3.7), closed deck, Nikasil Liners, forged pistons, newest design IMS.
Con Rods, is it worth paying for the likes of Carrillo, or are standard con-rods with uprated ARP bolts adequate? – What benefit would Carrillo bring how often to the standard rods fail?
Standard heads, is there anything else available? Are there any know fixes for the cracking issue? – Input welcome
Standard Cams, is there anything else available, is it a worthwhile upgrade? – Input welcome
Porsche Motorsport Air/Oil separator, worthwhile over the standard item?
Lightweight Flywheel & Sprung clutch, balanced to crank. – Thoughts on this? I know there are concerns about the crank, however the 3 different builders I have spoken to see nothing but benefits.
996 X51 Intake & Runners
997 X51 Exhaust manifold/headers (with Ti studs)
IPD Competition 83mm Plenum & 997 GT3 83mm Throttle body
BMC Panel Filter in standard airbox.
FVD Motorsport sump with X51 Baffle
Car will be remapped when complete.
Car already runs LTT, center rad and will get the water pump, chains, guides, bearings, seals etc etc done as part of the rebuild.
I know oil surge may still be an issue, pressure and tappet carrier, but I do not think I can stretch to rectifying these, if even reliable fixes exist, but again comments are welcome on these issues.
What am I missing?
Thanks
09-04-2018, 09:52 AM
#2
Rennlist Member
You haven't stated your expected budget. Keep in mind, whatever your target budget is, you will likely find good reasons to exceed it when all is said and done.
What is your car worth in its present state? I don't know your market, but have you considered finding a GT3?
Yes, you get the Metzger engine, but you get so, so much more with the rest of the car that will cost a small fortune to try to replicate with a Carrera.
The other thing to consider is that all of the costs of the modifications are something you will never recoup if and when you sell it. Whereas a well maintained GT3 will depreciate far less or possibly appreciate (I'm not holding my breath
).
Then again, if you are simply looking for a fun project, that's a different story.
What is your car worth in its present state? I don't know your market, but have you considered finding a GT3?
Yes, you get the Metzger engine, but you get so, so much more with the rest of the car that will cost a small fortune to try to replicate with a Carrera.
The other thing to consider is that all of the costs of the modifications are something you will never recoup if and when you sell it. Whereas a well maintained GT3 will depreciate far less or possibly appreciate (I'm not holding my breath
).Then again, if you are simply looking for a fun project, that's a different story.
09-04-2018, 10:19 AM
#3
Rennlist Member
You haven't stated your expected budget. Keep in mind, whatever your target budget is, you will likely find good reasons to exceed it when all is said and done.
What is your car worth in its present state? I don't know your market, but have you considered finding a GT3?
Yes, you get the Metzger engine, but you get so, so much more with the rest of the car that will cost a small fortune to try to replicate with a Carrera.
The other thing to consider is that all of the costs of the modifications are something you will never recoup if and when you sell it. Whereas a well maintained GT3 will depreciate far less or possibly appreciate (I'm not holding my breath ).
Then again, if you are simply looking for a fun project, that's a different story.
What is your car worth in its present state? I don't know your market, but have you considered finding a GT3?
Yes, you get the Metzger engine, but you get so, so much more with the rest of the car that will cost a small fortune to try to replicate with a Carrera.
The other thing to consider is that all of the costs of the modifications are something you will never recoup if and when you sell it. Whereas a well maintained GT3 will depreciate far less or possibly appreciate (I'm not holding my breath
).Then again, if you are simply looking for a fun project, that's a different story.
09-04-2018, 10:32 AM
#4
Instructor
Thread Starter
UK market, 996.1 GT3 $90k. - Limited supply due to RHD, circa 196 in the country, all of which are garage queens as the value continues to rise.
3.4, C2, manual, non sunroof, aerokit, cup suspension, 3.7 build, cage, buckets etc circa $40k. - And I already have the car. The engine rebuild I have noted in the UK is circa $17k
The finances are a no-brainer, coupled to the fact that if the GT3 continues to rise in value I would be less inclined to use it on track which completely defeats the object.
Modding a 3.4 is fun and at the end I will have a car that i will use and will have similar performance to a GT3 for less than half the price.
If outright speed was the goal I would be taking my money elsewhere, Caterham, Radical etc etc.
Can anyone comment on my technical quires?
3.4, C2, manual, non sunroof, aerokit, cup suspension, 3.7 build, cage, buckets etc circa $40k. - And I already have the car. The engine rebuild I have noted in the UK is circa $17k
The finances are a no-brainer, coupled to the fact that if the GT3 continues to rise in value I would be less inclined to use it on track which completely defeats the object.
Modding a 3.4 is fun and at the end I will have a car that i will use and will have similar performance to a GT3 for less than half the price.
If outright speed was the goal I would be taking my money elsewhere, Caterham, Radical etc etc.
Can anyone comment on my technical quires?
Last edited by Evil Bunny; 09-04-2018 at 10:35 AM. Reason: .
09-04-2018, 10:50 AM
#5
Burning Brakes
I've got the 3.8l in mine from Flat 6 / LN Engineering. Basically a stage 2 performer package with upgraded pistons. The power band moved down significantly from where it was - it seems like the mid/low 6000RPM range is the sweet spot now.
I really can't comment on the need for 'just' new bolts versus all new rods though....
I really can't comment on the need for 'just' new bolts versus all new rods though....
09-04-2018, 11:35 AM
#6
Drifting
Does your engine need a rebuild, or are you just rebuilding for performance?
If your engine is fine currently, seems like you would save a ton of money by buying a blown motor or roller with a blown motor, rebuild that to your specs, and sell your engine or car as it is (stock usually sells for more than modded).
Going even further, all the engine mods you've listed are going to be expensive -- suspension and brakes that you will probably want to do next will be more expenses on top of that -- and you won't get anything back in resale. Why not buy a car that has already been track/race prepped and sell your current car? That would allow you to avoid almost all of the cost hit on performance parts that have no value on resale, and it may cost you almost nothing in total from what your car will bring. It may take a while to find your perfect track car for sale, but probably it will still be faster than all the work you need to do to upgrade yours. I've never priced track cars, so maybe my presumptions are wrong, but seems like buying a track-prepped has to be a lot less than building one.
Sorry for not answering your questions (I don't have answers for those), just tossing out the above as food for thought.
09-04-2018, 12:10 PM
#7
Instructor
Thread Starter
The car is already built, I have been tracking it for 18 months, it already runs the majority of cup suspension components, with the only acceptations being carriers and rear sub-frame, so factory JRZ dampers, Monoball top mounts, LCA's, Toe links, Cup sways, monoball droplinks etc etc.
Brakes are Giro disc floating, with Pagid RS29 pads, cup car brake ducts and Motul RBF660 - With sufficient cooling I find the stock calipers fine.
Lots of the parts listed above I already have, its only the rebuild internals I need to decide upon.
With respect to all, I have considered all of the options, its not a decision that has been taken lightly, however this is the way I am going.
Last edited by Evil Bunny; 09-04-2018 at 12:13 PM. Reason: .
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09-04-2018, 01:53 PM
#8
Three Wheelin'
Join Date: Jun 2016
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Frankly, I would ask the guys at Hartech, and do whatever they say. I am guessing that is where you are doing a 3.7 closed deck block anyways.
The rods are likely up to the challenge of a 3.7 build. I would look into internal coatings on the pistons/heads/valves. See:
https://www.hotrod.com/articles/hrdp...gine-coatings/
The rods are likely up to the challenge of a 3.7 build. I would look into internal coatings on the pistons/heads/valves. See:
https://www.hotrod.com/articles/hrdp...gine-coatings/
09-04-2018, 03:53 PM
#9
Burning Brakes
Hartech over in the UK are the best people to talk to.
Have you considered an engine transplant from a newer 911? if I recall correctly its a lot easier to pass MOT etc with an engine swap in the UK than over here stateside (esp in CA)
Have you considered an engine transplant from a newer 911? if I recall correctly its a lot easier to pass MOT etc with an engine swap in the UK than over here stateside (esp in CA)
09-04-2018, 05:07 PM
#10
Instructor
Thread Starter
You guys are on it! - Hartech will be doing the rebuild.
The challenge in the UK is modifying is not as popular in the US, add this to the fact that Hartech have only recently made the closed deck 3.7 available there is not a lot of historical info available. Both options on the con-rod front have been offered with the guys stating that con-rod failures are rare and when they occur its usually down to the fixings/bolts, not the rods.
However I only want to be opening up the bottom end once, hence me trying to gain some info on the benefits, if there is any, of spend $2k on Carrillo or whether $300 of ARP fixings is adequate.
Chris MA, I would have loved to have dropped in a 3.8 X51 motor, but the expertise for doing such a thing is very thin on the ground here, read non-existent
The challenge in the UK is modifying is not as popular in the US, add this to the fact that Hartech have only recently made the closed deck 3.7 available there is not a lot of historical info available. Both options on the con-rod front have been offered with the guys stating that con-rod failures are rare and when they occur its usually down to the fixings/bolts, not the rods.
However I only want to be opening up the bottom end once, hence me trying to gain some info on the benefits, if there is any, of spend $2k on Carrillo or whether $300 of ARP fixings is adequate.
Chris MA, I would have loved to have dropped in a 3.8 X51 motor, but the expertise for doing such a thing is very thin on the ground here, read non-existent
09-04-2018, 05:30 PM
#11
Burning Brakes
You guys are on it! - Hartech will be doing the rebuild.
The challenge in the UK is modifying is not as popular in the US, add this to the fact that Hartech have only recently made the closed deck 3.7 available there is not a lot of historical info available. Both options on the con-rod front have been offered with the guys stating that con-rod failures are rare and when they occur its usually down to the fixings/bolts, not the rods.
However I only want to be opening up the bottom end once, hence me trying to gain some info on the benefits, if there is any, of spend $2k on Carrillo or whether $300 of ARP fixings is adequate.
Chris MA, I would have loved to have dropped in a 3.8 X51 motor, but the expertise for doing such a thing is very thin on the ground here, read non-existent
The challenge in the UK is modifying is not as popular in the US, add this to the fact that Hartech have only recently made the closed deck 3.7 available there is not a lot of historical info available. Both options on the con-rod front have been offered with the guys stating that con-rod failures are rare and when they occur its usually down to the fixings/bolts, not the rods.
However I only want to be opening up the bottom end once, hence me trying to gain some info on the benefits, if there is any, of spend $2k on Carrillo or whether $300 of ARP fixings is adequate.
Chris MA, I would have loved to have dropped in a 3.8 X51 motor, but the expertise for doing such a thing is very thin on the ground here, read non-existent
https://www.ebay.com/itm/Porsche-911...xZBPV2&vxp=mtr
https://www.ebay.com/itm/09-12-Porsc...NZCkbd&vxp=mtr
https://www.ebay.com/itm/13-Carrera-...pYD8ji&vxp=mtr
09-04-2018, 09:30 PM
#12
Rennlist Member
You guys are on it! - Hartech will be doing the rebuild.
The challenge in the UK is modifying is not as popular in the US, add this to the fact that Hartech have only recently made the closed deck 3.7 available there is not a lot of historical info available. Both options on the con-rod front have been offered with the guys stating that con-rod failures are rare and when they occur its usually down to the fixings/bolts, not the rods.
However I only want to be opening up the bottom end once, hence me trying to gain some info on the benefits, if there is any, of spend $2k on Carrillo or whether $300 of ARP fixings is adequate.
Chris MA, I would have loved to have dropped in a 3.8 X51 motor, but the expertise for doing such a thing is very thin on the ground here, read non-existent
The challenge in the UK is modifying is not as popular in the US, add this to the fact that Hartech have only recently made the closed deck 3.7 available there is not a lot of historical info available. Both options on the con-rod front have been offered with the guys stating that con-rod failures are rare and when they occur its usually down to the fixings/bolts, not the rods.
However I only want to be opening up the bottom end once, hence me trying to gain some info on the benefits, if there is any, of spend $2k on Carrillo or whether $300 of ARP fixings is adequate.
Chris MA, I would have loved to have dropped in a 3.8 X51 motor, but the expertise for doing such a thing is very thin on the ground here, read non-existent
09-05-2018, 06:04 AM
#13
Instructor
Thread Starter