calling guillotine!

[v8 racing]

Hi andy i have been dyno testing a griff engine today with similar specs to yours apart from this had an act triple plenum and i was gutted at the results!! 320ftib and 288 bhp!! now we have a fully enclosed dyno cell with fan to control room temperature etc... but all i did was conect a pipe from the airflow meter to the gate in the wall to pick up fresh cold air and the power went form said figures to 342ftlb and 309 bhp, conclusion i would take a good look at how your airflow is getting into the motor?? i did spend an hour or so looking at a griff airfilter and to be honest i dont know if the same is happening to you, but on my race engine at high air speeds across the intake it was actualy drawing air out of the trumpets!! so on the rollers if the fan they use is doing the same on your car this could be wear the problem lies?? just a thought but definetly worth investigating?

[HarryW]

Not quiet at the same level as the big boys in their 5ltrs .
When I had mine on a RR recently the start figure was down from an expected 260/70 to 230/40 after some work around the front of the engine. Turns out the Ali induction tube that passes over the LH hand manifold & Y piece was knocked so it was resting on the manifold it heated up so much it felt like the manifold itself never-the-less it equated to around an instant 30hp .
I'm quickly coming to the conclusion that anything I can do to isolate the inlet side from heat has got to well worth the effort.

Harry

[tiny]

I've just fitted ACT's new silicon induction hose(twixt AFM and front filter/intake)- Rich at Peninsula reckons that this is good for about 8 BHP.

Got the car on Mech's rolling road this Friday when Mark Adams will fine tune the other mods I've had done (V8Dev cam/ACTtwin/Ceramic exhaust/Tornado chip)

[starmist]

I'll be there too! Intersting about the silicone hose / hot air issue. I should be having a silicone hose delivered to Mech Repairs in time for Friday's session.

What exactly is the issue with the airbox? Are you saying that the airflow over / though the front of the car at speed is causing so much of a vacuum that it's sucking air OUT of the intake trumpets, or have I misunderstood you?

Is there any mileage in fitting a NACA style duct in the bonnet, or some other type of air scoop, and drawing cool air directly from there? Has anyone tried this?

[v8 racing]

andy a little birdie told me today your air filter is direct onto the airflow meter is this right???

[HarryW]

v8 racing said:

andy a little birdie told me today your air filter is direct onto the airflow meter is this right???

I always thought the AFM liked a section of straight pipe (10" or so) before it to let the air stabilise first .

Harry

[v8 racing]

your dead right on that harry and your other post to do with hot air in the airtake, but on a griff that means the filter is directly above the exhaust headers which may explain why he is 20 horses down all the time

[Guillotine]

Hey Guys...sorry i'm late, 'bin at Oulton Park today and was VERY HAPPY with the way the car went.

Was alot of very expensive race cars there (360 challenge, GT3 , Radical etc etc so had to get out of the way alot but was still able to post times around the 2m10s mark which i thought was pretty good for a first visit.

Rob, the cams great (the hydraulic 404 for those who don't know [404H]) everyone should have one and i reckon they probably will! very little lost on the 404 but smooth as silk and even after a hard day on the track, not to mention 200mile each way, still quiet as a wisper. no resetting the tappets for me this weekend!


easily able to post sub 3sec times on the 80 - 100mph in fourth test (my personal power test) even in the wet today!! and 2.3-2.5 being the norm. factory figures put this at 3.9s.

will be at mech on friday with tiny and starmist so we should be able to get several readings for similar cars on the same day in the same conditions.

as far as the air induction goes...

i have tried mine with KN (400bhp) filter, improved front positioning and at the mo have it plugged onto the air mass meter so i can get an oil cooler in! at the front that is...
no diference to power in any case!
the posituion is temporary tho, am construcing a free flow air box just off the amm with clean and DIRECT air feed from the front. will let you know how we get on with that.

from your results, this does seem to be the issue. and i can believe it. did further engine tests while fitting the cam (compression again, bleed down etc) and everything is tickety boo. rockers are starting to wear but only just and the preload takes it. so now we need the right injectors in and we'll see what its up to then.

will get a run as is tho for 404/404h comparisons. probably down a touch be well worth it for me.

cheers again rob...be in touch!

>> Edited by Guillotine on Wednesday 28th April 21:30