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Advice : C20LET Inlets (450-500bhp)...

8K views 31 replies 11 participants last post by  Boets 
#1 ·
hoping to run 500bhp and looking into inlets.
just after some infomation on what standard intakes can handle.

Standard inlet with EDS Tophat

or a handmade one?
i can ally weld so making one up isent a problem and saw these inlet manifolds so you can run injectors (alot cleaper the SBD ones) make a box for the top and have a throttle body on the side like Rick Drapers




cheers for the advice
 
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#2 ·
BeArDy said:
hoping to run 500bhp and looking into inlets.
just after some infomation on what standard intakes can handle.

Standard inlet with EDS Tophat

or a handmade one?
i can ally weld so making one up isent a problem and saw these inlet manifolds so you can run injectors (alot cleaper the SBD ones) make a box for the top and have a throttle body on the side like Rick Drapers




cheers for the advice
got a link to get one of those beardy? and like you say make a tapered inlet plenum to go on the back of that and bobs ya uncle, can't see 500bhp being a problem infact i would put money on someone doing that power this year
 
#6 ·
Stefan said:
You need to be more specific. What is your application? What sort of powerband are you aiming for? What will your max rpm be?
I have lots of details I can pass on to you if you answer the above :)
i realise that anyone can build a bridge that won't calapse but it takes a engineer to build a bridge that will only JUST not colapse ;)
but if he puts a tapered box (plenum) and some venturi's which he/i could knock up in our metal work shed as it were, to similar guestimated dimesions as the swedish cossie inlet plenum that flows 800bhp it would do what we want aka 500bhp ??? imo
 
#20 ·
I have the Vmax tophat :D Nothing wrong with the LET standard manifold with bigger tophat. But a custom will free some power if designed correctly.

Craig
 
#21 ·
The art to getting these manifolds right is having the same amount of air travel into each cylinder - muti Tb's is the better way of doing this, although probably an arse to setup on a Turbo motor ??

My mate had phase 4 and some custom inlet and regal could never get the engine to run right with it on ?? why this were I couldn't say though ??

With an EDS TB and tophat (both the EDS and Vmax tophats are 60mm) and a matched (ported to match the gasket) standard manifold - I can't see no reason why 500bhp can't be had ??
 
#23 ·
artfulmatt said:
The art to getting these manifolds right is having the same amount of air travel into each cylinder - muti Tb's is the better way of doing this,
Why is that Matt ? I thought tb's could only give you some advantage in throttle responce. If you have a different amount of air "hanging" before your tb you'll still have a different amount going into your cil's. And where it really matters, full power, you'll have wide open throttle.

Tbh i think it's very hard to make a really good aftermaket manifold.
very very few are really tested on a flowbench, or compared with others on a proper dyno.
So i think moste designs, most common the tapered box, won't make too much of a difference to eachother.

I've based my intake on rallycross and WRC intakes, and i've got some simulation pics of it. But if it's really giving me advantages, i don't know. Havent had it on the flowbench or compared it with another possible setup.
 
#24 ·
RobbieS said:
Why is that Matt ? I thought tb's could only give you some advantage in throttle responce. If you have a different amount of air "hanging" before your tb you'll still have a different amount going into your cil's. And where it really matters, full power, you'll have wide open throttle.

Tbh i think it's very hard to make a really good aftermaket manifold.
very very few are really tested on a flowbench, or compared with others on a proper dyno.
So i think moste designs, most common the tapered box, won't make too much of a difference to eachother.
it makes a serious difference!
 
#26 · (Edited)
if there are several tested on the same setup, is suppose it can.
But how can you say upfront which is best or most suitable for a certain application? I've seen a lot of different types of manifolds but still i can't say which one is best.

This is JUN's approach


with results, i like that


This is a rallycross intake, i believe the Reyland Escort has a same type


And these are 2 simulation setups, one plain and simple design, and one more like the rallycross type.



It's not only the design that needs to be right, there are also differences in the size of the airtank. It can be too big, or too small.
 
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