CJ Posted October 19, 2004 Share Posted October 19, 2004 I was certain I had seen a thread where the weight of aftermarket pistons and con rods had been listed. I have tried a search but to no avail. Anyone help? Link to comment Share on other sites More sharing options...
MONKEYmark Posted October 19, 2004 Share Posted October 19, 2004 would it really make much of a difference, thought you would be more concerned them holding the power. Link to comment Share on other sites More sharing options...
dude Posted October 19, 2004 Share Posted October 19, 2004 Originally posted by MONKEYmark would it really make much of a difference, thought you would be more concerned them holding the power. Rotating mass !!!!!! Dude Link to comment Share on other sites More sharing options...
CJ Posted October 19, 2004 Author Share Posted October 19, 2004 I may be wrong Mark, but i was led to beleive that not only should you be looking for stronger bottom end parts but also lighter. The reason given was that a lighter component would give less rotating mass when put under an extreme centrifugal force. Link to comment Share on other sites More sharing options...
dude Posted October 19, 2004 Share Posted October 19, 2004 Lister diesals are really strong !!!! they just dont rev too quick !!!! Dude:flame Dev Link to comment Share on other sites More sharing options...
TLicense Posted October 19, 2004 Share Posted October 19, 2004 Out of interest though Colin, why are you looking at rebuilding the bottom end. They're fairly well proven to hold BIG power, or have you got something seriously silly in mind Link to comment Share on other sites More sharing options...
Digsy Posted October 19, 2004 Share Posted October 19, 2004 Its reciprocating mass that light pistons and rods helps - mainly the piston. A light piston makes the con rod, rod bolts and rod bearings' lives easier because of the reduced inertia loading at TDC on the exhaust stroke. It should only be an issue really if you are planning on revving any higher than stock. If you keep the revs to the stock limit then the stock setup should be adequate from a mass perspective. Link to comment Share on other sites More sharing options...
TLicense Posted October 19, 2004 Share Posted October 19, 2004 Originally posted by Digsy It should only be an issue really if you are planning on revving any higher than stock. If you keep the revs to the stock limit then the stock setup should be adequate from a mass perspective. Does anyone know, or have heard of anyone that has significantly raised the rev limit? It's one of things I've always thought would be a good way to go would be to raise the rev limit to like 10K, and have a huge great big turbo, shorten the gear ratio's and then just drive higher up in the rev range to help deal with the lag. I was actually told if you wanted to raise rev limits the top end was what you'd need to strengthen/lighten. Sorry Colin, back to the thread, errr no I don't know where that thread is. Link to comment Share on other sites More sharing options...
CJ Posted October 19, 2004 Author Share Posted October 19, 2004 Well, thats sort of where I am coming from. When my car was on the dyno, the power was still increasing only to be stopped due to hitting the rev limiter. I then thought that maybe I should look to increase the rev range and considered the strengthening / lightening of the bottom end as insurance. I am also considering fitting a Nos kit which may also mean me looking at certain strengthening jobbies. Link to comment Share on other sites More sharing options...
dude Posted October 19, 2004 Share Posted October 19, 2004 Originally posted by TLicense Does anyone know, or have heard of anyone that has significantly raised the rev limit? It's one of things I've always thought would be a good way to go would be to raise the rev limit to like 10K, and have a huge great big turbo, shorten the gear ratio's and then just drive higher up in the rev range to help deal with the lag. I was actually told if you wanted to raise rev limits the top end was what you'd need to strengthen/lighten. Sorry Colin, back to the thread, errr no I don't know where that thread is. Theres not too much too lighten up top Tony (no rockers etc) , i allready have Ti retianers and much stronger springs , i suppose lighter stronger valves maybe , but im trying to get some of those custom made as we speak Dude:flame Dev Link to comment Share on other sites More sharing options...
dude Posted October 19, 2004 Share Posted October 19, 2004 Originally posted by CJ Well, thats sort of where I am coming from. When my car was on the dyno, the power was still increasing only to be stopped due to hitting the rev limiter. I then thought that maybe I should look to increase the rev range and considered the strengthening / lightening of the bottom end as insurance. I am also considering fitting a Nos kit which may also mean me looking at certain strengthening jobbies. Its not just strength CJ its the way the car/engine behaves , imagine it revving quicker like a bike and you'll get close Dude:flame Dev Link to comment Share on other sites More sharing options...
eyefi Posted October 19, 2004 Share Posted October 19, 2004 cj, there's a list on mkivsupra.co.uk. i think thats what u might b thinking of. revs kill engines, its pretty much the big reliability killer. do u feel since fitting the single that u need more revs? Link to comment Share on other sites More sharing options...
CJ Posted October 19, 2004 Author Share Posted October 19, 2004 Hi eyefi Thanks for that - I will look later (you dont have a link do you?) I dont think i NEED more revs, it is just that the car has more power available but the rev limiter stops it reaching the full potential. In saying that, it might be different when I fit my new BL box next week and the changes are quicker etc. Link to comment Share on other sites More sharing options...
eyefi Posted October 19, 2004 Share Posted October 19, 2004 aye, here it is Link to comment Share on other sites More sharing options...
CJ Posted October 19, 2004 Author Share Posted October 19, 2004 much horse grassy arse Link to comment Share on other sites More sharing options...
Miguel Posted October 19, 2004 Share Posted October 19, 2004 The BL box is not gonna make your car rev more so if your power is being limited by the revs then yes you NEED more. But in saying that Eyefi is correct REVS kills lumps at minimum ARP studs in the bottom end. Still it ALL depend on how far and how much power you want to go . IF this car is for racing only I think the investent in a bottom end is on the book BUT if its to use every day then i think you need to limmit your goals and stick with the bottom end you have (ARP min) . After all look at the dyno queens in the states with over 900bhp on OEM bottom...need I say more, They can take the risk as some of these cars are ONLY used for racing . You pays ya dough and makes ya choice Link to comment Share on other sites More sharing options...
TLicense Posted October 19, 2004 Share Posted October 19, 2004 I've just been trying to find if anyone, anywhere has pushed the limits of the engine with regards to revs. The only person I could find without spending hours looking, was Peter Blach, but he's rebuilt the bottom end anyway, and he still only rev up to 8K, according to his dyno plot on to4r.com. Anyone willing to test this and find out what the limit of the bottom end is? Link to comment Share on other sites More sharing options...
CJ Posted October 19, 2004 Author Share Posted October 19, 2004 Again, good info guys. OK, so whats your advice? Here I am with a single conversion and putting out quite a high BHP. I am going to be fitting a Nos kit in the near future and will be using the car for mainly fast road use with drag races in between. The current spec shows uprated cams and fuelling and may include a future stand alone EMS. Now, to get th full power from the car, I will have to raise the revlimit. If i did this, what should i be looking to strengthen - if anything? Just a full ARP bolt and stud kit? Conrods? Pistons? Link to comment Share on other sites More sharing options...
CJ Posted October 19, 2004 Author Share Posted October 19, 2004 Originally posted by migster The BL box is not gonna make your car rev more so if your power is being limited by the revs then yes you NEED more. The reason I sited the box was that I felt it would change quicker than my current stock box is doing and would therefore not have me hitting the limiter - of course, that might be complete bollox and if it is then I apologise Link to comment Share on other sites More sharing options...
Miguel Posted October 19, 2004 Share Posted October 19, 2004 Originally posted by CJ The reason I sited the box was that I felt it would change quicker than my current stock box is doing and would therefore not have me hitting the limiter - of course, that might be complete bollox and if it is then I apologise Yes it will change quicker therfore hitting the rev limit quicker:D Link to comment Share on other sites More sharing options...
CJ Posted October 19, 2004 Author Share Posted October 19, 2004 Originally posted by migster Yes it will change quicker therfore hitting the rev limit quicker:D Smart arse Link to comment Share on other sites More sharing options...
eyefi Posted October 19, 2004 Share Posted October 19, 2004 Originally posted by TLicense Anyone willing to test this and find out what the limit of the bottom end is? u've got the 10k tach a lot of the supraforums guys run over 7k (i guess yr wanting more than a couple of hundered over stock) and quite a few 8k with various levels of mods. i think its all a bit risky and would not buy their cars from them. cj, do a search on piston speed, there should b some interesting reading for bedtime. i think the s2000 has the highest piston speed of any stock car and the bottom end in there is a bit trick. have u got a dyno plot since the single? Link to comment Share on other sites More sharing options...
Alex Posted October 20, 2004 Share Posted October 20, 2004 I believe PHR have "tested" a car upto 10,300rpm...and they've run a 2JZ at over 9,000... I believe their built crate engines are rated for as much... A JUN valvetrain kit for £1600+shipping + some lighter pistons and rods would see you right to about 8-8,500...but it's a trade off between revs and reliability. And don't forget you'll be over speeding you ancillaries at over 7,000rpm, thus they could have reliability issue's too. Link to comment Share on other sites More sharing options...
Robbie Posted October 20, 2004 Share Posted October 20, 2004 Hi CJ I'm working With GT-ART at the minute on my project car . One of the things Gary's done is work hard to modify the head on the car with a mind to rev to 8500 rpms and not go pop! The bottom ends' been upgraded as well with ARP bolt and JUN rods and Pistons. It might sound a bit much but If your serious about getting the most from the engine Gary would be a good person to call. Robbie Link to comment Share on other sites More sharing options...
CJ Posted October 20, 2004 Author Share Posted October 20, 2004 Thanks Robbie Can I ask what work has been done to the head? Link to comment Share on other sites More sharing options...
Recommended Posts
Please sign in to comment
You will be able to leave a comment after signing in
Sign In Now