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Supercharger Fitting Guides
- Thread starter RSi Dave
- Start date
lol i can't believe anyone would even consider paying nearly £300 for a hairdryer motor, a bit of silicone hosing and a cheap filter.
There was a post about this elsewhere, its rediculous, i heard somewhere a 1.8 uses like 12,000 litres of air in one min at 6000 revs, can a hairdryer supply more than that? and any built up pressure will be forced back out of the fan. I think its a complete lie, That's one of the biggest rip off's ive ever seen IMO
There was a post about this elsewhere, its rediculous, i heard somewhere a 1.8 uses like 12,000 litres of air in one min at 6000 revs, can a hairdryer supply more than that? and any built up pressure will be forced back out of the fan. I think its a complete lie, That's one of the biggest rip off's ive ever seen IMO
BenR said:
Last say that on a low boost (like this topic refers to) the engine wont go into the problems that always comes up with high boost aplications.
When you have an engine that at 3500rpm delivers 100Nm torque and at 4000rpm you have a 300Nm or more torque something will crack soon. Good EMS can prevent this by air injectors, etc etc which will deliver a smoother torque over the rev range which even the gearbox will thank you.
Std EMS's usually can't control boost (the crap solenoid that only opens the vacum line to the actuator isn't a good boost control) so full boost just burts.
smillie said:
You're refering to the 40k rpm supercharger from ebay right?
Off-topic
BenR said:
This is because the long stroke (92mm or so) right?
Yes, high torque loads will cause something to fail, but it WONT be the rod bolt if your not running any high RPM. Especially when you bring into the fact that peak torque is never right at the top of the rpm range.
And renault components fall apart because they just arent made that well.
Honda B20 92mm stroke applications with similar R/S ratios can live at above 9000rpm on stock components.
And renault components fall apart because they just arent made that well.
Honda B20 92mm stroke applications with similar R/S ratios can live at above 9000rpm on stock components.
I just know that every zetec engine turboed with std con bolts fail! And this with only 280bhp at 6500rpm. ARP is the solution for this one (CVH engines above 180bhp also should go ARP con bolts).
So, to get a F7R or F4R going above 7000rpm all day at a track day what is involved? And at what rough price?
So, to get a F7R or F4R going above 7000rpm all day at a track day what is involved? And at what rough price?
There were too many 2lts zetec turboed engines with broken rod bolts. They started to use ARP bolts and then the std con rods were the limit (anyone for banana's?).
I think there never was a lab or a more cientific look to way it has happened. Broken con bolt = weak bolt... ARP con bolt survive = good bolt.
I think there never was a lab or a more cientific look to way it has happened. Broken con bolt = weak bolt... ARP con bolt survive = good bolt.
BUTRE said:
yes mate i am indeed. you can tell me its not true all you like mate, im telling you it is!!
ive explained in real life terms what ACTUALLY happens (not hear-say on ford forums) why the rod bolts would be ok....NOW, you explain to me why the bolts would fail under increased cylinder pressure, given the same max engine speed.....
BUTRE said:
forged pistons-circa 400
h-section rods-circa (complete with high tensile cap bolts) 500 +vat
dynamically balanced cranktrain (grey area, but i'd do it out of course anyway)
that wot i run BE on my personal car.
then u would want to look at revised valve-gear depending on cams/rpm etc
intresting reading guys, keep it going!
My engine is an F3P which means people do jack all for it. as far as im aware the F7 engines are very different so not to sure on running there stuff.
Bit of history, its currently on 64k and the cam belt was changed about 10k ago.
So far nothing has gone wrong with it, standard rev limit is 6.5k however this might get increased slightly when running different management.
As in the ford thread, i would only be running low boost and see how things run. The good thing about them m45 chargers is that if i buy one and it wont fit or work then i can sell it back on ebay and make my money back so nothing lost.
Fred - let me know about that outlet fabrication for the cooper charger. Will be intrested.
My engine is an F3P which means people do jack all for it. as far as im aware the F7 engines are very different so not to sure on running there stuff.
Bit of history, its currently on 64k and the cam belt was changed about 10k ago.
So far nothing has gone wrong with it, standard rev limit is 6.5k however this might get increased slightly when running different management.
As in the ford thread, i would only be running low boost and see how things run. The good thing about them m45 chargers is that if i buy one and it wont fit or work then i can sell it back on ebay and make my money back so nothing lost.
Fred - let me know about that outlet fabrication for the cooper charger. Will be intrested.
This is the last time I'm posting about this because the last posts went way off what RSi Dave created this topic in the first place. Sorry about that Dave.
Stan, you belive what you want to belive. I simply don't care what is your experience in engines either NA or forced inducted. For what I've seen here, you could be a little more open minded in learning something instead saying everyone is wrong if they desigree with you.
On this topic subject, I would go ARP rod bolts since I don't know how strong is the std ones from Renault. Also, the price for ARP rod bolts is nothing compared to their quality that has been proven over and over again.
Dave RSi, how good is your French? I bet that french foruns have loads of information about supercharging renault NA engines... I'm really bad at French (even with google translating for me) but I'm really curious about this project of yours
A low-boost aplication would be a nice way to start since once done... there's never enough BHP
Stan, you belive what you want to belive. I simply don't care what is your experience in engines either NA or forced inducted. For what I've seen here, you could be a little more open minded in learning something instead saying everyone is wrong if they desigree with you.
On this topic subject, I would go ARP rod bolts since I don't know how strong is the std ones from Renault. Also, the price for ARP rod bolts is nothing compared to their quality that has been proven over and over again.
Dave RSi, how good is your French? I bet that french foruns have loads of information about supercharging renault NA engines... I'm really bad at French (even with google translating for me) but I'm really curious about this project of yours
A low-boost aplication would be a nice way to start since once done... there's never enough BHP
it could be if the install/mapping was crap....this wot i was meaning earlier bout "the chicken and the egg"...its hard to say wot happened first sometimes ina series of event sthat lead to mahjor failure.
1) poorly mapped, det could haved cause piston failure, and holed the block....under severe circumstances albeit...
2) poorly built engine, ring fitted upside down (!) or cracked on install---piston failed etc etc
3)oil evacuated from bearing surface due to higher cyl pressure....cap failure
all give near enough same end result.....
other thing to consider is where the info was sought....one person could claim one thing happened, another could claim something different. esp on the net where "real-life" happenings are sometimes hard to determine froma few pics and ill-applied lack-of understanding.
1) poorly mapped, det could haved cause piston failure, and holed the block....under severe circumstances albeit...
2) poorly built engine, ring fitted upside down (!) or cracked on install---piston failed etc etc
3)oil evacuated from bearing surface due to higher cyl pressure....cap failure
all give near enough same end result.....
other thing to consider is where the info was sought....one person could claim one thing happened, another could claim something different. esp on the net where "real-life" happenings are sometimes hard to determine froma few pics and ill-applied lack-of understanding.
Ok, Already knowing that rpm is one of the things to look at when tuning an engine, if it must go above std rpm then engine internals must be checked, as con rod bolts already issued here.
Why I say std con rod bolts can fail even when not going above std rpm?
Bolts suffer from fatigue at stress points (usually stress points are sharp edges/corners) that usually are there because of bad part design or for the std aplication is more than enough so no need to go better because production costs would climb.
At NA usually (unless huge upgrades which had to go for above std rpm and so the first rule aplies first) the rods and caps dont bend at each revolution. On forced inducted (lets say turbo) engines rods and their big-ends (or caps) are more to bend even thou the rod wont turn into a banana.
(Before anyone comes here saying that if it bent it should stay bent, its what yeld strength is all about. You can stretch steel, stop stretching it and it will go back to its original shape. I know it can seem bizare, but I do it everyday at work).
This slight bending of the con rod and its big-end WILL stress the stress points and with this fatigue appears in the form of microscopic internal cracks... until it brakes.
How to avoid all this?
Without knowing how much beating can the std bolts handle, its really hard to tell.
Now, ARP appeared for this reason (I think). They manufacter uprated bolts to replace std ones that are made from better materials, better design (less stress points than std ones) and give the how-to torque them into place with the right lub the right way.
Geting back to the RSi project:
- Don't know how good are the std bolts.
- ARP bolts are better than std ones for shure!
- Is it worth going ARP? I mean, adding a cost to the project...
http://rallynuts.com/motorsport/ARP...Pro_Series_Conrod_Bolts_Renault_Clio_2327.asp
Even I can afford ARP bolts with my lousy Portuguese salary!!!
Hope this helps cleaning my point of view since it was blured by my lack of time to come here and type a proper-understandable post.
Why I say std con rod bolts can fail even when not going above std rpm?
Bolts suffer from fatigue at stress points (usually stress points are sharp edges/corners) that usually are there because of bad part design or for the std aplication is more than enough so no need to go better because production costs would climb.
At NA usually (unless huge upgrades which had to go for above std rpm and so the first rule aplies first) the rods and caps dont bend at each revolution. On forced inducted (lets say turbo) engines rods and their big-ends (or caps) are more to bend even thou the rod wont turn into a banana.
(Before anyone comes here saying that if it bent it should stay bent, its what yeld strength is all about. You can stretch steel, stop stretching it and it will go back to its original shape. I know it can seem bizare, but I do it everyday at work).
This slight bending of the con rod and its big-end WILL stress the stress points and with this fatigue appears in the form of microscopic internal cracks... until it brakes.
How to avoid all this?
Without knowing how much beating can the std bolts handle, its really hard to tell.
Now, ARP appeared for this reason (I think). They manufacter uprated bolts to replace std ones that are made from better materials, better design (less stress points than std ones) and give the how-to torque them into place with the right lub the right way.
Geting back to the RSi project:
- Don't know how good are the std bolts.
- ARP bolts are better than std ones for shure!
- Is it worth going ARP? I mean, adding a cost to the project...
http://rallynuts.com/motorsport/ARP...Pro_Series_Conrod_Bolts_Renault_Clio_2327.asp
Even I can afford ARP bolts with my lousy Portuguese salary!!!
Hope this helps cleaning my point of view since it was blured by my lack of time to come here and type a proper-understandable post.
i think you are still confusing compressive and tensile stress issues. yes, your right there are stress concentration issues, but you are confusing how they effect a con-rods performance...due to tens/comp.
as for bolts, you havnt really explained WHY they are better:
they have a wasted shank which removes stress concentration by balancing stress levels throughout the body of the bolt i.e. no part of it is stronger than another. Comparing this to the standard bolt the shank is of a greater diameter than the threaded section. This will create a great stress concentration around the sharp change in profile and in the threads themselves. Secondly, the threads on the up rated bolt are rolled rather than cut. Instead of cutting or shearing the material, as is the case of single point threading, thread rolling cold forms the profile to be produced. In this process, the component material is stressed beyond its yield point, being deformed plastically and thus permanently. A hardened die made from tool steel or High Speed Steel (HSS) displaces the material along the contours of the thread profile, plastically deforming the material into the final form. The work piece material is stressed beyond its yield point, which causes it to flow and conform to the mirror image of the dies profile.
the grain lines of the rolled material are not interrupted like those of cut material, instead, they are compressed and moved more perpendicular to the centerline of the part, increasing the threads tensile strength by 10-30 per cent over cut threads.
the compression of the material during the rolling operation causes work hardening at the threads surface. This is most apparent in the threads root and along its flanks, making it more wear resistant also.
a rolled thread also has up to 70 % increased fatigue resistance (hence the higher safety factor) over a cut thread. Since rolling is a chip less operation, the profile is free from burrs, tear marks, chattering marks, and sharp exit points, all of which are focal points for stress. If a part were to fail from fatigue, it would fail here at the end of the thread, where the entire load is concentrated. Parts that are under a constant load such as a con-rod bolt greatly benefit from thread rolling because the threads have a smooth work hardened, radius and burnished run-out. so yes, ARP bolts have greater fatigue resistance....
back to fatigue for our scenario, fatigue faliure is increased by either the magnitude of stress being applied, or the number of cycles. the stress applied to the bolt under greater cylinder pressure simply IS NOT increased, hence fatigue failure is no more likely.
i have computer generated FEA somewhere for conrods and bolts if you need any further proof....
as for bolts, you havnt really explained WHY they are better:
they have a wasted shank which removes stress concentration by balancing stress levels throughout the body of the bolt i.e. no part of it is stronger than another. Comparing this to the standard bolt the shank is of a greater diameter than the threaded section. This will create a great stress concentration around the sharp change in profile and in the threads themselves. Secondly, the threads on the up rated bolt are rolled rather than cut. Instead of cutting or shearing the material, as is the case of single point threading, thread rolling cold forms the profile to be produced. In this process, the component material is stressed beyond its yield point, being deformed plastically and thus permanently. A hardened die made from tool steel or High Speed Steel (HSS) displaces the material along the contours of the thread profile, plastically deforming the material into the final form. The work piece material is stressed beyond its yield point, which causes it to flow and conform to the mirror image of the dies profile.
the grain lines of the rolled material are not interrupted like those of cut material, instead, they are compressed and moved more perpendicular to the centerline of the part, increasing the threads tensile strength by 10-30 per cent over cut threads.
the compression of the material during the rolling operation causes work hardening at the threads surface. This is most apparent in the threads root and along its flanks, making it more wear resistant also.
a rolled thread also has up to 70 % increased fatigue resistance (hence the higher safety factor) over a cut thread. Since rolling is a chip less operation, the profile is free from burrs, tear marks, chattering marks, and sharp exit points, all of which are focal points for stress. If a part were to fail from fatigue, it would fail here at the end of the thread, where the entire load is concentrated. Parts that are under a constant load such as a con-rod bolt greatly benefit from thread rolling because the threads have a smooth work hardened, radius and burnished run-out. so yes, ARP bolts have greater fatigue resistance....
back to fatigue for our scenario, fatigue faliure is increased by either the magnitude of stress being applied, or the number of cycles. the stress applied to the bolt under greater cylinder pressure simply IS NOT increased, hence fatigue failure is no more likely.
i have computer generated FEA somewhere for conrods and bolts if you need any further proof....
Last edited:
MarkM said:
only if your running big boost imo
a low boost application i.e 7psi and under , i'd be suprized if the rod bolts snapped. The weakest link when it dets is the pistons themselves and they will proberly melt,
butre, the problem is your applying your understanding of metals and forces in the wrong way.
The basics of what you say are not incorrect in the sense of the characteristics of metals and applied forces. However they have no true relavence to the subject we are speaking.
I think the simplest way to put it is........If you were to run the compression stroke with NO cap on the rod, it'll still go round and it'll still transmit the torque without any cap or rod bolts.
The basics of what you say are not incorrect in the sense of the characteristics of metals and applied forces. However they have no true relavence to the subject we are speaking.
I think the simplest way to put it is........If you were to run the compression stroke with NO cap on the rod, it'll still go round and it'll still transmit the torque without any cap or rod bolts.
Tried to keep it simple but ok.
What does BBPT uses on their high boost F7P? This can help since they went over alot of problems that only appeared with high boost aplication.
Just checked this:
http://www.arp-bolts.com/Catalog/Catalog.Images/ARPCatalog.pdf
Should have done it in the first place so that no one can say now that ARP is crap because they go against someone's ideas.
BenR, I'm just curious that ford engines are known to brake the con bolts when the NA engine is converted to high boost turbo. That's why they all started to go ARP and now everything is holding in place.
I've made my point and stan yes I've answered your PM. I'm glad that you edited your last post (yes I've read it before you edited it) since that was too much if you know what I'm saying. Let's just leave it this way ok?
What does BBPT uses on their high boost F7P? This can help since they went over alot of problems that only appeared with high boost aplication.
Just checked this:
http://www.arp-bolts.com/Catalog/Catalog.Images/ARPCatalog.pdf
Should have done it in the first place so that no one can say now that ARP is crap because they go against someone's ideas.
BenR, I'm just curious that ford engines are known to brake the con bolts when the NA engine is converted to high boost turbo. That's why they all started to go ARP and now everything is holding in place.
I've made my point and stan yes I've answered your PM. I'm glad that you edited your last post (yes I've read it before you edited it) since that was too much if you know what I'm saying. Let's just leave it this way ok?
Spykee said:damn this is an interesting read! some of you guys really know your stuff!!
i was going to contribute seeing as you can do a nice eaton conversion to a G60 but there isnt any point with the knowledge on here!
im just going to observe instead
Alex
I think that there is always room for new ideas, etc etc. If there wasn't we would still be cuting seats at 30º to improve flow like Gordini and Abarth did!
nobody said ARP was crap, i use ARP alot, but were simply talking of higher compressive forces on a rod assembly leading to rob bolt failure.
The only reason i can see is not directly because of combustion forces, but from the accelerative jerk forces from the next firering cylinder affecting a cylinder on the take stroke as the journal will be pulling on the car. And the crap R/S ratio will make fore higher jerk acceleration forces at the TDC to 90 deg ATDC region. OR....the exhaust stroke decelleration phase 90 BTDC to tdc.
The only reason i can see is not directly because of combustion forces, but from the accelerative jerk forces from the next firering cylinder affecting a cylinder on the take stroke as the journal will be pulling on the car. And the crap R/S ratio will make fore higher jerk acceleration forces at the TDC to 90 deg ATDC region. OR....the exhaust stroke decelleration phase 90 BTDC to tdc.
I've always said that ARP is good, just said
Never thought about that Ben... I really don't know why, but I'm into the rod bending (without going above yeld) and hitching the stress points on the bolts theory.
Don't belive in supernatural stuff but I do belive in ghosts living inside our engines lol
because even ARP says that rpm is not the only thing to take into consideration and I know that this will go against alot of belivers. It seems that the other factors are not well undisclosed, maybee because they are not that relevant for the majority of the wrecked engines.BUTRE said:
Never thought about that Ben... I really don't know why, but I'm into the rod bending (without going above yeld) and hitching the stress points on the bolts theory.
Don't belive in supernatural stuff but I do belive in ghosts living inside our engines lol
