View Full Version : 743 cams
Paulius94
23rd September 2015, 11:32
Hello guys,
I have problems again.... I buyed and putted 743 cams.Then some guys remmaped.Cams adden +14hp.But.....but nothing really changed.Top speeds in straights changed only by +6km/h and I think its because I started to use better tyres and better brakes..(Faster in the corners,late braking).Guy who mapped said its impossible and it should be much more power in 6800-7300rpm.
Before 743cams my saxo had 135hp.After- 149hp on their dyno.I went to other company to have dyno ant it showed only 135hp with cams and full exaust?(I once been there without cams and full exaust it showed 135hp.
These guys says what its something not really good with fuel mixture?
What you think can be wrong?Nothing in my country ever mapped that car like saxo/106gti....
How much speed you get then added cams?Or it is felt going on track or road?
KamRacing
23rd September 2015, 11:55
Get it up against a standard saxo and you should notice the difference in power. It sounds like you've just got used to it. 14bhp is significant but ultimately you are not going to be knocked into your seat. You need a lot of power to increase the top speed of a car by a large margin so you should be looking at how fast your car gets there as it will plateau when it cannot push against wind resistance.
You should also be able to look at the dyno report. This will tell you how well its been mapped as you can look at the fueling through the rev range.
Paulius94
23rd September 2015, 12:43
Yes I understand what 14hp is not very much.But I think it really should increase speed by 5-8mh/h on straights or no?Because Kam racing exaust system added 4-6km/h in the straigt.I was impressed by that and thought what 14hp should add more.
Before cams I run on track with nankang ns-r .Speed in last corner before longest straigt was 112km/h and in the straigt maximum what I was always pushing 167km/h.After remmap I have took part in some seriuos competition.For them I bought toyo R888R,so my speed in last corner was 122km/h and in the straigt I pushed only 173km/h + very very late braking.So cams added just (maybe) a few km/h in the straigt? Its really hard to compare it because I raced with very different tyres....My friends say it very weird because for them cams changing added a lot more speed in that track(They all drive civics).
So I just dont know what to think..
KamRacing
23rd September 2015, 13:50
I would change back to the original tyres you were using pre-cam and then test the car to see how the laptimes differ. You could always take it to the dyno where it was mapped and check the car out so you have a direct comparison on your data. Changing dyno will always give a different bhp result.
axsaxoman
24th September 2015, 08:07
my guess --
car is overgeared as these cams will make the extra power at higher rpm --so what is max rpm you get too ?
if not where you make power --theres your answer
panizzi
24th September 2015, 11:44
Toyo 888 only available as 195/50-15 size
i guess that is what you mean talking about overgeared
KamRacing
24th September 2015, 13:17
overgeared as in your gearbox is the limiting factor by not allowing you to rev high enough on the straights to benefit from the extra power further up your rev range.
If you had smaller wheels and tyres to swap and compare, you would effectively gear down your car so it would be a way of testing.
Paulius94
24th September 2015, 16:12
I always was using 195/50 R15 with lighweight wheels.Well... yeah maybe it can be the reason.In the straight start I am going 4gear from about 5.5-7.3rmp and 5gear till about 6.2-6.5rpm and then braking.My gearbox drive ratio 4.30.
I am adding my dyno.Sorry for bad quality.
https://scontent-ams3-1.xx.fbcdn.net/hphotos-xtf1/v/t34.0-12/12033632_865218456860388_1323531714_n.jpg?oh=1455c f67e377d7c8d38b077fabc76632&oe=56063E58
Paulius94
24th September 2015, 17:07
Dotted line in dyno graph is before cams.
axsaxoman
26th September 2015, 06:34
graphs dont work--turn them in to jpeg
Paulius94
26th September 2015, 11:03
http://i989.photobucket.com/albums/af16/julijaR6/12067098_865817056800528_743409417_n_zpsugb6s2q9.j pg
axsaxoman
29th September 2015, 08:38
I always was using 195/50 R15 with lighweight wheels.Well... yeah maybe it can be the reason.In the straight start I am going 4gear from about 5.5-7.3rmp and 5gear till about 6.2-6.5rpm and then braking.My gearbox drive ratio 4.30.
I am adding my dyno.Sorry for bad quality.
https://scontent-ams3-1.xx.fbcdn.net/hphotos-xtf1/v/t34.0-12/12033632_865218456860388_1323531714_n.jpg?oh=1455c f67e377d7c8d38b077fabc76632&oe=56063E58
sorry your final drive is too high to get best out of those cams --where yuor max bhp is would be over 140mph --even touring cars with 300bhp do not gear that high and you got half the bhp -
Paulius94
29th September 2015, 09:54
You mean I need to lower my final drive ratio to maybe standart vts(Longer gears) Not to get it highter(4.5-4.6) for shorter gears?I understand right?
Because if cams give best power at high rmp's(6700-7300) in my head I need highter final drive ratio....
KamRacing
29th September 2015, 10:39
John means you need to shorten your overall gearing.
axsaxoman
1st October 2015, 09:13
I max bhp rpm is 7500 then it should be geared for 125 mph at that rpm-- or there abouts
vBulletin® v3.8.2, Copyright ©2000-2025, Jelsoft Enterprises Ltd.