F355GTS Posted May 4, 2006 Share Posted May 4, 2006 I need to make my car quieter particularly induction, I've seen Franky's bulk buy with useful info on Pipercross bits and am tempted to take the plunge I'm running QED DTH TB's with 47mm Trumpets and ITG filter Specific questions are 1. Is the backplate for the ITG the same? it looks like it 2. Is 100mm intake large enough for a 270bhp engine 3. Am I wasting my time if I don't get a new bonnet without cutout Thanks Mark Link to comment Share on other sites More sharing options...
Jason Plato Posted May 4, 2006 Share Posted May 4, 2006 1- no its not the same as a pipercross ☹️ 2 - I ran 102 mm on 247 bhp with no issues. I reckon it will be fine 3 - depends on your clearance between bonnet and tb's . you could always make your own out of alluminium sheeting into a box ? . The car would need to be remapped if you ran a pieprcross box. I foudn large variances in the fueling with and without an airbox, mainly as a result of reflective pulses inside the airbox - I now have 2 maps on file Dave Link to comment Share on other sites More sharing options...
Myles Posted May 4, 2006 Share Posted May 4, 2006 DJ - hmm - interesting point about fueling... I added a 15-20mm (or so) spacer between the backplate and BS airbox to improve the clearance of the 90mm trumpets (similar to what OBNS did) - I'm wondering if this is contributing to what appears to be a general richness in the running... Bit of a shame if it does - that suggests I'm filling the cylinders less efficiently, doesn't it??? Project Scope-Creep is live... Alcester Racing 7's Equipe - 🙆🏻™ Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
Rob Walker Posted May 4, 2006 Share Posted May 4, 2006 My 1.8K was run at Emerald on Tuesday with and without the Bernard scouse airbox, the airbox has been modded to 102mm entry and has a very large K&N conical filter fitted. With the air box 213bhp without the airbox 230bhp and the engine lost around 12lb ft torque accross the range, the losses were progressive from 4000 rpm. Its a lot quieter but the losses are higher than I had expected. I am running with 90mm trumpets as supplied with the airbox. I think these are too close to the inner face of the airbox and are effecting the inlet pulse, fitting 75mm trumpets may yeld better results. Link to comment Share on other sites More sharing options...
Myles Posted May 4, 2006 Share Posted May 4, 2006 That was the point of my spacer... Not sure if it's made the right sort of difference... Project Scope-Creep is live... Alcester Racing 7's Equipe - 🙆🏻™ Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
Davey Bee Posted May 5, 2006 Share Posted May 5, 2006 Mark, I would like to know how you get on with this, as I will have the same issues. There must be someone with a big power Vx that as fitted one of these air boxes or something similar. TRY 5S Confussed Link to comment Share on other sites More sharing options...
Jason Plato Posted May 5, 2006 Share Posted May 5, 2006 Rob - interesting results with and without the airbox . I knew it would make a difference but as was said on previous threads and as we have discussed - quite how much is impossible to determine without a back to back rolling road test. As a comparision, and an example of the differences between different setups and engine specifications and the effect of running an airbox .here are my power plot on my 1900 from last year , with and without the Bernard Scouse air box. I actually made more power with the airbox then without - possibly as a result of reflective pulses ?? . This was using the 90mm trumpets supplied with the airbox - so these cannnot be blamed for a loss of power in every instance. However , this year the specification was changed slightly (exhaust, cam timing ) and the airbox produced 10bhp less when fitted. But loosing XX Bhp is better than getting thrown off track ? and the box is certainly is nice on the road especially if you are on a long trip So my point is that the effect of an airbox on any particular engine is hard to estimate, it certainly alters the fueling requirements across the range and realy needs to be mapped to get a decent setup and comparison . Myles - changing trumpet length adds another variable which can result in different fueling through the range . 20mm is quite a considerable change on a K series and could have a marked effect on the engines requirements and performance. Edited by - Dave Jackson on 5 May 2006 08:20:32 Link to comment Share on other sites More sharing options...
frankyknuckles Posted May 5, 2006 Share Posted May 5, 2006 Mark, The filter in the pipercross box is only rated to 230bhp (from memory). www.R300.net Link to comment Share on other sites More sharing options...
Rob Walker Posted May 5, 2006 Share Posted May 5, 2006 Dave, We tried various cam timing settings to try and recover some losses. This worked but the best results were down 17bhp approx 7.5% at peak. Interestingly I am using 90mm trumpets inside the airbox and 18mm spacers outside. I do agree its nicer to drive without the noise, on track at Cadwell thrashing round all day I was able to concentrate on my driving and did not suffer the usual headache and ringing in my ears. So I will live with the losses however its always hard to give up hard earned power. Rob Link to comment Share on other sites More sharing options...
Nigel Riches Posted May 5, 2006 Share Posted May 5, 2006 Someone told me years ago that the minimum clearance from the end of the bellmouth / trumpet to the inner face of a covering airbox should be 1.5 x the auxillary venturi diameter, regardless of length of intake trumpet. Not sure if this is gen or an old engine builder tale, but seems reasonable, at least as a starting point. Regards Nigel. 1982. 5 speed, clamshells. B.R.G / Ali. The True Colours. Link to comment Share on other sites More sharing options...
F355GTS Posted May 5, 2006 Author Share Posted May 5, 2006 It's all getting complicated and expensive!, I can use hte Airbox but as Dave posted the filter is only rated ot 230BHP so Airbox without the filter then, well yes but the ony 100mm filter is 200mm in diameter and very noisy according to Pipercross os they feel I'd gain little in terms of noise reduction I'm waiting to hear back from their techs but at the moment it looks like it might use one of these here inline, a bit pricey at £250 plus the Airbox at £180 and the piping etc ☹️ Mark Link to comment Share on other sites More sharing options...
John Howe Posted May 5, 2006 Share Posted May 5, 2006 Franky, when I spoke to Piper on the issue of power they related the 230 bhp to 75mm ducting and concluded that the 100mm would make it all fine... JH Deliveries by Saffron, the yellow 230bhp Sausage delivery machine Link to comment Share on other sites More sharing options...
Myles Posted May 5, 2006 Share Posted May 5, 2006 Myles - changing trumpet length adds another variable which can result in different fueling through the range . 20mm is quite a considerable change on a K series and could have a marked effect on the engines requirements and performance. DJ - think you've misunderstood me. The trumpets haven't changed - they are still 90mm. The spacer moves the airbox out from the backplate - so providing better clearance between the airbox wall and the mouth of the trumpets... Project Scope-Creep is live... Alcester Racing 7's Equipe - 🙆🏻™ Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
Harry Flatters Posted May 5, 2006 Share Posted May 5, 2006 Another big VX here looking like it may have to go this route. My setup is a little different from Marks running 48mm Jenvey Tapered TB's on manifold with 90x48mm trumpets with ITG dome filter. Any suggestions welcome. *arrowright*Harry Flatters *arrowright* AKA Steve Mell - Surrey AO and Su77on Se7ener Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now