I can only use 4 injectors to comply with regs in my race class. Ive got a 500 plenum and throttle body etc.. but is their any advantage in using it over a std 2 wd one ?
I know the 500 kit is bigger but does it really make any difference when im only using 4 greys ?

 

IMO Use a 4x4 plenum, this is nearly as big as the RS500 and cheaper but use the RS500 throttle body.
Use 850cc Jap injectors for huge power and better running/emmissions.
Just Did a 500 BHP engine using this set up and it ticks over like a
standard car. !

 

Thanks Simon ,

How do you suggest fitting the 500 Throttle body to the 4x4 elbow ?
Will be in touch about the Wasted spark P8 soon ,
Thanks Mate

 

Good question, I dont know how that was done.
I did not build the engine, just the electronics.

I have a feeling, a FIAT/LANCIA or FERRARI (weber) throttle body was used
which is the same size as the RS500 but does not have the integral idle
valve.

 

Simon the throttle body your are talking about is off a lancia intergrale and accepts a rs 500 size hose and fits to the normal plenum elbow, the reason it does this is because the TB is tapered and the actual butterfly is the same size as the 2wd item which is more than capable of flowing enough air for 600+BHP

HTH

PJay

 

Sorted !! Cheers PJay

 

Pjay ,

If its true the 2wd TB can flow that much air , is the answer to my question that there would be no advantage to using the 500 manifold for just a 4 injector set up ?

 

As already said it depends on the power you wish to run, the restriction is in the plenum elbow.

PJay

 

If you already have the RS500 plenum / throttle body setup, why not just keep it on there? All you have to do then is fit 4 high flow injectors in the upper rail and use any old injector in the lower rail to blank the injector holes with, fit a 2wd regulator and cap off the lower fule rail, you'll also never have to worry about restrictions in the air flow either

 

Wes , thats probably what i'll do . The question was really to find opinions on whether at the power level i will be running @ 400hp , there is an advantage in using the 500 TB and elbow over the std one ! As i already have the 500 kit i think i'll use it so i can use the bigger intercooler ,all this aids power and ACT's .

I have no knowledge about big capacity jap injectors , can you really get similar power to 8 injector engines at lower boosts ? I will be using a T35 .63 , race turbo ,P8 , BD 14's etc.. Would be interested to hear how other people have got on , especially if you fancy dyno'ing my engine after its built !

 

I would say yes there is an advantage, it's less restrictive to air flow, imagine blowing the same amound of air through two different bore tubes, the larger tube gives less resistance. The best cover to use other than the RS500 is the EECIV (used on the small turbo escort cosworths), this has been dyno proven by Mike Rainbird on SCS's dyno to be the best of the rest. But as you already have the RS500 stuff then you may as well utilise it! It would be silly to use the throttle body on a 4x4 cover, you then have an RS500 plenum cover that is useless, as it is the throttle bodies which are rare as you know what

As for the injectors, I would say no you won't get similar power at lower boost levels, the boost levels will need to be the same as for the 8 injector setups! the injectors just flow more fuel so you can use less of them, the more fuel + air the more power you get You may (depending on injector type) need to change the ECU to do this, as the Webber Marelli based ECU's can't cope with most of the newer injectors (different impendance types), there are a few that do work though

Do your regulations specify turbo size also?

 

In actual fact the Weber ECU's can cope with Modern injectors but the
software in them cannot !!!
I have a program for a L6 that controls 700cc Jap injectors lovely but not yet
dyno proven as I have put all my effort into my own ECU.

I (and others) have had good results from 700cc Jap injectors (greys are 550cc)
and on pump fuel, these theoretically can give around 520 BHP
with excellent emmissions control (subject to port sizes).

 

Thanks Guys ,

These are the sort of answers and questions in was hoping for !
Wes , the biggest turbo i can use is a T35 before i have homologation problems ,although this year ,for the first time im allowed to use a non std fit intercooler ( as long as its sourced from the range ! i.e The 500 one !). So ,if i can use a 500 intercooler and the eligibility scrutineer lets me get away with a 500 plenum only running 4 injectors , its a no brainer really ,the extra bore TB &elbow is free perfotmance .so i'll use that .

Simon ,
As i already have a P8 that runs greys To 400hp ,i'll probably stick to that for a while ,the turbo i have may not show the benefit of bigger injectors !
thanks

 

Ah OK, i was only thinking you'd be better of running a T38 or even a T4, 400 bhp is around the max you will get with a T34, and the power drops of at around 6500 RPM. Could you not use a T4, as this was fitted to the range as standard on the RS500 , you'll have power all the way upto the redline then, and more of it too

 

If i use a bigger turbo i'd fall into the same class as multi injectors and 4wd , my poor little 2wd Sierra has trouble with 4wd cars ,so i stick to class B , won it last season !

The rules have swung my way tho for this season , in that i can use a bigger intercooler ,hence the Q's about the plenum advantages of the 500.