cr500dom

I too have been asked to contact you about this by another 7 owner who is coming up your way next weekend.

could you let me have a contact number please ?

cheers

Dom

Are these still available ?

Just a recomendation for these, they are fantastic TB`s with virtually no restriction at Wide open Throttle, due to the shaftless design.

Filter back plate or airbox gets trapped between the ram pipe and extension tube as well, so a nice clean installation.

cheaper to sell it and buy a duratec powered car if thats what you want ?

Or speak to stuart at Premier power about a 175 conversion ?

What are you trying to acheive ?

Peiro is good, Stuart (PP) is good, and scholar are good, personally as they built it I`d be going back and discussing options with Alan at Scholar. 

No But Aerocoat a little further afield do a very good job.

Or speak to Luke Stevens at Team Leos Motorsport near newmarket, he will know who to use locally ? 

@Barkalarr these have got your name on them :D

Every engine is different, Id want to try a selection of different lengths on the dyno to get the optimum.

Port design and cam timing will have a bearing on what will work, too many variables without running a proper 1D simulation to get somewhere close.

Dave Walker (emerald) has adjustable length trumpets available, might be worth seeing if he does a set to suit your Bodies ?

As for throttle plate position, very often this is driven by packaging rather than what is optimum for the particular engine.

Also the Jenvey pattern tooling and casting process is somewhat modular, which often drives the spindle position.

You can fit a Metric Cage to an imperial chassis, but not the other way round.

Some engines just dont need big throttles, The sigma, we did an oval blade with an effective diameter of 42mm, which is fine for over 200hp

We built a set at 45mm for testing with a customer who was convinced they were strangling the motor at the top end.

It made no more power but lost torque everywhere else with teh larger throttles.

What made a much bigger difference was intake length, both on top end power and lower end torque.

Most ITB systems, even on 16V engines have intake lengths that are really too short.

My Sigma set of direct to head throttles have something like 180-190mm trumpet length behind the butterfly and my Zetec (On jenvey dcoe bodies as thats what was fitted) has probably 150mm post butterfly but has a longer intake tract because of the manifold.

This makes good power with only cams and rod bolts on a std Blacktop crate motor at 205hp but has 160lbs/ft of torque too with a really nice fat curve.

Higher port velocity means greater cylinder filling in most situations, it would always be my preference to increase rather than decrease port velocities.

It also helps with fuel mixing and tumble. 

Butterfly closer to the head is better for transient response and drivability, this is difficult with a traditional DCOE style body because of the manifold required.

Direct to head allows you to position the butterfly much closer than a DCOE style.

50's on a 2.0L sounds like a serious motor ? 9000rpm ? and 250+ hp ?

A number of years designing engines and induction systems including Throttle bodies means I stand by what I said regarding throttle position.

M-Bob, If you already have the Bodies then that's different.

The theory says you lose port velocity with a bigger diameter, (Which was always more of an issue with carbs) in practice its less of an issue.

I`d use the smallest bodies that will give you the power output you seek, but be aware, power is addictive.

If you go 48's I doubt you will lose any noticeable driveability over 45's but you will not be choking it at higher revs.

All in my humble opinion of course, you are free to use whichever internet wisdom you choose 

Thanks Guys

PM`s are on their way

Hi All, I`m after a pair of windscreen stanchions for an S3 please, and doors to suit the same car too

Mine is a metric chassis if that makes a difference ?

Cheers

Dom

Dont go dcoe bodies on a Duratec, Jenvey and AT power both do Direct to head bodies which are much better.

You want the butterfly as close to the head as possible too and DCOE bodies wont allow you to do that.

If you are trying to get close on maps, then you need the throttle position to be similar to the Roller Barrel position too or it doesnt work.

TBH you are better off fitting the right hardware, a lambda guage and mapping it on the road will get you close enough to not do any damage.

But I wouldnt comprimise the performance because of hardware just to save yourself an hours mapping.

Theres a whole load of us who do regular trackdays at Snetterton in Caterhams, you are always welcome to tag along.

1st day, and less than 100 miles on the ar ?

Id be checking the service and warranty requirements with bookatrack first.

Id be wanting at least an oil change before taking that on circuit.

In a 620 you wont need an aeroscreen for now, that`ll have more than enough power.

Garage is useful especially if its wet, means you can store all your gear too.

do your belts up tight, especially the lap belts and add some tywraps or elastic bands to stop the ends of the belts flapping in your face

Sit in the car, belts on, helmet on, engine off and just relax and clear your head for a couple of minutes (This is good before each session I find)

Get at the front of the queue for the sighting laps

Get some instruction early too

build up slowly, take lots of breaks and only do 10-15 minute sessions.

I always take it steady for a couple of laps too, just to get some heat into the tyres and let everything come up to temperature gradually before getting quicker.

Always do a cooldown lap as well before coming in, it is much kinder to the car, and allows you to wind down too. High gear, low load, fans and heater blower on etc and swift pace rather than pressing on.

Just relax, and most of all enjoy it !!!

Or Cut halfway through the old belt, fit the new belt, then cut the rest of the old one off.

Nothing moves then and you dont need to know the cam timing settings.

I got enough parts, in stainless steel, from wixroyd to do this at far less cost than CC

Luke Stevens, at Team Leos just outside Newmarket has an R400D SV available I think

You guys need to speak to @Barkalarr on here

He can get new glass fitted into your surrounds very easily.

I brought one of these:

https://www.amazon.co.uk/gp/product/B017IJ9IX0/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1

And its been great, not started a car off it yet but I use the pump all the time and use it for charging phone and usb stuff.

Had agreed to buy this, all arranged (Although not paid for as we were discussing some additional parts)

Get a messsage today to say hes sold it to someone else

Thanks very much Mike

Peter I have a caliper Wind back tool if you ever need to borrow it ;)

Its pretty comprehensive, and will do most calipers, left handed or right handed wind back too

I`ve got an R500 K Series Caterham Carbon Airbox available if you want to do the job properly ?

Yes Neil (Barkalarr) is who to speak to, he can do you a much better solution than the GT Tarp type covers for similar money but much greater security, and he will have a trailer and cover in stock I bet