650 Flow Bench Data

hello Dale,

when you do this flow procedure,with OEM valve settings 30-35,how much power can you gain??

Or change the power curve through the rpm???

greetings Madero

i have put the two charts on a sheet and tried to follow the results. degrees and lift in thou are all i can make out?

was that improvement on both the inlet and exhaust sides together?

only i changed my 400 from 35/27 to 35/29 and the hit came at around 4k as well i would think. so that was just the exhausts.

regards

Taffy

a must for any aspiring rider by the sounds of it. 17% increases at higher lifts. impressive indeed.

thanks for clearing that up for me.

regards

Taffy

Hello All,

To Dale or other mecanics:
Is there a lot of difference between my 31,5exh valve(from lineaweaver) and the 32mm in the kit you changes here above??


Will I gain power when I put 37 and 31,5mm valves but do no porting job ??
or is this necessary to have better results??

Thanks to all,
Madero

Ps;Because I am busy with the 750kit,I probably have advantage to have bigger valves.

Hi dale,

First of all I am very happy and content with the 31,5 pro flow valves.
It is worth every Dollar or Euro.(thanks for the fast reply)


But it is difficult when the tuners have all an other idea of what tuning is.
for example I had a good internet adress (flo head works for HD engines) about porting cilinderheads, some tuners says it is important that you have small intake ports (I know it was on a 4 cil and high RPM engine,R6),to have a fst flow,other say the bigger the better.I did the the porting job myself but gained no or nothing on HP the only advantage was that the power came faster out of the wheel(regarding special Dyno file I 've made in the past)

I will start on the 750 kit with 35-31,5 OEM valve and later with my X2 cam,what was for me not a big gain.If the power is good and fast I will leave it.

Today I have met,an engineer of Fiat and Iveco,they worked with CAD for drawing and also with a special program that calculated the force 's in the engine,this is very good to predict some technical problems,
for me and I think a lot of amateur tuners it is TRIAL and ERROR principle.
And the disadvantage is that you can loose a lot of money.

Greetings MAdero

madero

i ported my own exhaust ports and had a significant improvement at 1/3rd revs plus. loved it. i had 35/27 and decided the exhausts were too small. so i pulled the 30's i had in my big valve head and reduced them to 29mm and then fitted them. i did the porting using washers i had machined by my engineer to help me keep an eye on how straight it all was. they had a 6mm centre hole and all i did was put a threaded rod through each disc and shine a torch from behind the port. anywhere that was starting to lose the roundness was ported out and all kept sweet.

it took me about 6 hours per port.

i then measured up the inlet ports and the angle of entry and felt that the bottom of the inlet port was too low and that the 'cross sectional area' was too large. so i purchased some devcon and 'welded' the port area at the base mostly. guides out. seats 'three-way cut' and then ported it.

it IS important which way up the inlet rubber is (pre '03s) and i took a little out around the guide area. but my bike is a 400 not a 650 so i don't need what husaberg give.

the upshot was that i again had a boost in power with the inlet side done. however at 7pm one day, with the bike still muddy and on the trailer i left it out overnight because i wanted to test the next morning.

i had a flat spot up to 1/3rd throttle and then someone would hit a button and the thing would go!!!! dale told me it was the pipe and as it happened i had had an open pipe waiting to be tested for 6-months (are you reading this bigbob?) and after dale said it's your tailpipe i went out the next morning, one 'old run' new tailpipe and bingo! the bike pulled from everywhere!

i had jetted up for safety and then came back down to where i was.

if i can offer anymore advice on doing this yourself then please contact me. to me it wasn't that hard. the hardest bit for the home mechanic is keeping the workshop clear.

i would think the exhaust valves netted 2-3 hp and the inlets another 1-2 hp.

i did very little in reality to the inlet ports but you would do a lot, lot more and the gains will be significant i'm sure.

i'm not sure why you 're running 35/31.5. i'm sure dale hasn't recommended those tiny inlets so it must be for the compression or something akin?

i would think that 37s would be the minimum needed.

what a monster you're building!

regards

Taffy

I did some engines in the past,and my experiences was with the intake valves to big The powerband changes too much.
I mean,on bottom lost and max out put at to many RPM 's that gives too much loads on the bottom end .

That is my goal to ride with 35-31,5 DOMA system and ?or OEM cam ?X cam,I would like much and fast power But I do not like to rev like a crazy lunatic.I like power on bottom and mid,inhigh is to Physical for me.

That is only my idea,and it is possible that I will need bigger intake valves,but we are not so far at the moment>

then madero my dear fellow you need to have the same port measurements as me don't you!

i've got a pot of devcon here that i have taken one egg full from. i'll even send you the washers as well if you want.

if you want someone to do it for you-i'll have a crack at it...

regards

Taffy

Cheers all!
Here´s my flow bench data from comparing a stock head with my billet cylinder head.

Best regards,

Dr_C

Hi.


I get also 160cfm at 10mm lift with stock head.