Batfink 201 Posted November 7, 2007 I'm gradually collecting the parts I need for building my racecar and i've come to the stage where I want to map out my engine spec as i'm collecting parts when I am unsure I will use them now i'm planning to race in a class from 1401cc to 1700cc and it seems wrong to try modding an 8v (sorry purists) I have an mi16 engine, a steel crank, dry sump etc Now with a bit of maths i've worked out I can get dead on 1700cc with a 1.6 crank and 86mm pistons and liners. Well 1700.58cc so I hope a scrutineer will round down! there are some hurdles to overcome as I need to keep weight to a minimum to be competitive due to the penalties of runnng a sequential gearbox. Miles can provide 86mm liners and modified blocks i believe. Will mi16 rods fit on a 1.6 crank? I think I can get a custom crank with extra counterweights from catcams, or maybe I can run a billet crank from a 1.6 with no modification? should be a rather revvy engine. not sure what power I can get but 170bhp should easily be possible with the right cam i would have thought. Realistic power? Race engines can get well over 100bhp per litre so maybe 200bhp is possible at a stretch. This would be similar cost to building a 2.2litre version but that would put me in class B against some serious turbo machinery and i think i would be mad to jump in at the deep end. Share this post Link to post Share on other sites
pdd144c 0 Posted November 7, 2007 You'll be in Class B with that setup anyway mate. Box means you'll have to go up a class. Unless we aren't talking about DMN.... Class C Up to 2000cc: multi-valve Up to 1600cc: forced induction Class D Up to 2000cc: dual-valve Up to 1600cc: multi-valve Share this post Link to post Share on other sites
Batfink 201 Posted November 7, 2007 (edited) not DMN - far too crowded and its a bit of a power series now lol Did they change the rules that anything with sequential goes in class A? I'm looking at the Classic modified series and then Eurosaloons - Eurosaloons group C is up to 1750 for modified class but dropping 20cc (86.5mm pistons) will make me eligible for both series. Edited November 7, 2007 by Batfink Share this post Link to post Share on other sites
taylorspug 7 Posted November 7, 2007 Why do you need the sequential box? With a small relatively low torque engine in a 205, the lowest possible weight is going to be the key isnt it? It would be worth using one if you were going to struggle to get down to the class minimum, (so would effectively be carrying the penalty anyway), but i cant see that being the issue, considering how light you can make a 205. Do they add on a set amount of weight for using a sequential box? Share this post Link to post Share on other sites
Sandy 191 Posted November 7, 2007 For up to 1700cc, I would tempted to think TU 16v. Share this post Link to post Share on other sites
wardy18 33 1 Cars Posted November 7, 2007 (edited) where can you source sequential boxes from for the XU9 205 i recently went to a rally and heard a 306 maxi with a sequential box and couldnt beleive my ears when it changed gear sorry to jump in by the way Edited November 7, 2007 by wardy18 Share this post Link to post Share on other sites
kyepan 291 Posted November 7, 2007 he mentioned something about 2 seconds a lap from the sequential when i last spoke to him about it. Share this post Link to post Share on other sites
pdd144c 0 Posted November 7, 2007 Ah ok. The new ruling for next year is that a sequential box moves you up a class. LMA would be good though! Sandy TU would be a great option, but I'm not sure the CTCRC rules would allow this. Share this post Link to post Share on other sites
Batfink 201 Posted November 7, 2007 (edited) taylorspug said: Why do you need the sequential box? With a small relatively low torque engine in a 205, the lowest possible weight is going to be the key isnt it? It would be worth using one if you were going to struggle to get down to the class minimum, (so would effectively be carrying the penalty anyway), but i cant see that being the issue, considering how light you can make a 205. Do they add on a set amount of weight for using a sequential box? there is no weight penalty - only a class penalty. Minimum weight for a 1.7 will be 640kg which will be a challenge - though I plan to be there... sandy309 said: For up to 1700cc, I would tempted to think TU 16v. true, but i have loads of cool bits for xu engines, and most of the parts needed for the engine can be used for a big capacity alloy block with a crank change should I want to play with the big boys. hey i just like to be different ;) To purchase similar parts I have for a tu engine would cost a small fortune. With what I have I can experiment somewhat too. Apparently with a dry sump you can run less piston rings so less parasitic losses wardy18 said: where can you source sequential boxes from for the XU9 205 i recently went to a rally and heard a 306 maxi with a sequential box and couldnt beleive my ears when it changed gear sorry to jump in by the way My gearboxes are the old 405 touring car ones so dont often come up for sale. I've only seen two for sale ever and i've bought them lol Europe is the best bet as the 405 was far more popular and successful on the continent. Edited November 7, 2007 by Batfink Share this post Link to post Share on other sites
Batfink 201 Posted November 7, 2007 Finding threads like this dont help my desision lol http://forum.205gtidrivers.com/index.php?s...c=81054&hl= People have done it before yay! Share this post Link to post Share on other sites
Sandy 191 Posted November 8, 2007 pdd144c said: Ah ok. The new ruling for next year is that a sequential box moves you up a class. LMA would be good though! Sandy TU would be a great option, but I'm not sure the CTCRC rules would allow this. Why is that? Iron block TUs were fitted to the 205, so it would only be a head swap, like the Mi16? (I'm not familiar with the rules) Share this post Link to post Share on other sites
pdd144c 0 Posted November 8, 2007 I'm not 100% familiar with them either, so worth checking, but I seem to remember someone saying they weren't allowed.... Share this post Link to post Share on other sites
Batfink 201 Posted November 8, 2007 i think the TU would be allowed. I thought boring the TU engine to 1700cc leaves the block walls very thin??? Share this post Link to post Share on other sites
B1ack_Mi16 67 Posted November 8, 2007 Batfink said: i think the TU would be allowed. I thought boring the TU engine to 1700cc leaves the block walls very thin??? Danish guys have done both 1860cc and 1920cc TU engines with other crankshafts and overbore. Share this post Link to post Share on other sites
Batfink 201 Posted November 8, 2007 (edited) so how good is the 1920cc one compared to an mi16 performance wise? Also by stroking a tu engine to get a greater capacity you create a more lazy revving engine, compared to a destroked mi16 Edited November 8, 2007 by Batfink Share this post Link to post Share on other sites
Sandy 191 Posted November 8, 2007 1628cc on a standard crank would be reliable and good for comparable power to most "1700" engines. Share this post Link to post Share on other sites
Dj_mini 7 Posted November 8, 2007 Quote true, but i have loads of cool bits for xu engines, and most of the parts needed for the engine can be used for a big capacity alloy block with a crank change should I want to play with the big boys. hey i just like to be different To purchase similar parts I have for a tu engine would cost a small fortune. With what I have I can experiment somewhat too. Apparently with a dry sump you can run less piston rings so less parasitic losses Iv found that the dry sump set up adds alot of weight with all the extra gubins and 10L of oil also so i think your struggle to get 640kgs Share this post Link to post Share on other sites
Powers 13 Posted November 8, 2007 Christ a 205 that weighs 640kgs! I would say that was almost impossible if not impossible! Share this post Link to post Share on other sites
Batfink 201 Posted November 9, 2007 Dj_mini said: Iv found that the dry sump set up adds alot of weight with all the extra gubins and 10L of oil also so i think your struggle to get 640kgs I doubt very much that I will be running 10litres of oil as the tank will be in the passenger footwell next to the bulkhead, maybe 6-7 max I would say. I have a few plans in motion for getting the car near my target weight so I'll have to wait and see if its successful or not. It wont be cheap but it will be unique! Share this post Link to post Share on other sites
taylorspug 7 Posted November 9, 2007 Quote there is no weight penalty - only a class penalty. Minimum weight for a 1.7 will be 640kg which will be a challenge - though I plan to be there... Ah ok, well worth the effort then if there is no actual performance penalty! What sort of thing will be running in your class then? Id say 640kg would be acheivable (just), you will have to go all out to get the weight off though! Share this post Link to post Share on other sites
Batfink 201 Posted November 9, 2007 Well Class C in the classic modified series this year had: Jos Ronchetti in his Lotus Sunbeam (moving to group A next year which is good as he's rather fast! - he's fitting a sequential box apparently) A Vauxhall Firenza, Mitsubishi Starion, Vento VR6 and an M3 E30 Share this post Link to post Share on other sites
Powers 13 Posted November 12, 2007 Batfink, it would be tempting to start a lightweight thread in more detail that Smckeown's one for someone planning the ultimate lightweight shell as you are. What do you think? Share this post Link to post Share on other sites
Batfink 201 Posted November 12, 2007 Probably a good idea. I'll keep a picture diary as I work and will measure the weights of everything as I fit them Share this post Link to post Share on other sites
