Mrb00ns Posted February 26 Share Posted February 26 With the sad demise of Premier Power, what options are out there for throttle body upgrades for a 420R (and of those, who would anyone recommend)? Cheers Chris Link to comment Share on other sites More sharing options...
aerobod - near CYYC Posted February 27 Share Posted February 27 Hi Chris, I’m upgrading my R400D to around 250bhp spec with Raceline Direct-to-Head 48mm Jenveys with 90mm ram pipes and Pipercross filter. An unlocked ECU (or a Tuner who can work on the locked Caterham MBE ECUs) and remapping will be required, of course. https://www.raceline.co.uk/products/part_section.asp?SectionID=13&CategoryID=1 1 Link to comment Share on other sites More sharing options...
Support Team Shaun_E Posted February 27 Support Team Share Posted February 27 I've got Raceline 48mm TBs on my 260bhp engine. If you aren't looking for more power then maybe 45mm would be fine but speak to them and they can advise. As James said above, you will need a remap. 1 Link to comment Share on other sites More sharing options...
Nigel B Posted February 27 Share Posted February 27 I had a set of second hand roller barrel throttle bodies fitted by Luke Stevens, followed by a mapping session by Luke & Steve Greenald. I was delighted with the result. The car runs better than ever, pulls smoothly & strongly & sounds fantastic! https://www.lukestevensdevelopments.co.uk/ 3 Link to comment Share on other sites More sharing options...
lapsedtheorist Posted February 27 Share Posted February 27 I’ve just built a 420R which has an S3 chassis and am curious to know whether individual throttle bodies akin to the above fit and work without cutting a hole in the bonnet? Link to comment Share on other sites More sharing options...
Chris SSR400 Posted February 27 Share Posted February 27 7 minutes ago, lapsedtheorist said: I’ve just built a 420R which has an S3 chassis and am curious to know whether individual throttle bodies akin to the above fit and work without cutting a hole in the bonnet? A hole is required on an S3 to fit airfilter or airbox. personally I think it looks great but Im bias. Link to comment Share on other sites More sharing options...
Ainsley Posted February 27 Share Posted February 27 I think the optimum length of the bodies may require cutting a hole, especially by the time you fit some sort of filter. Link to comment Share on other sites More sharing options...
Mrb00ns Posted February 27 Author Share Posted February 27 I think the hole in the bonnet is inevitable. just as a ballpark, what will the hole in the wallet look like for TBs Inc mapping etc? Link to comment Share on other sites More sharing options...
aerobod - near CYYC Posted February 28 Share Posted February 28 This is the ex-VAT list price of the Raceline parts, besides adapting the throttle cable and any sundries. I would expect with tuning time it will be about £2,000 plus VAT: You might already have the ‘green’ injectors, but the lower capacity ‘blue’ ones were fitted to my R400D from the factory and will max out with any increase above the standard Caterham 210bhp on the plenum system. Part Notes Quantity Ex-VAT Price Raceline DTH Throttle Bodies Set (Ported) 48mm, ported, with seals Set £595 Throttle Linkage inc Bracket Jenvey CLS1 1 £127 Throttle Linkage Mounting Bracket Jenvey LBU2 1 £24 Throttle Body Mounting Capscrew Set 1 £8 Ram Pipe 48x90mm 4 £160 Fuel Injectors Bosch Green 4 £260 Injector Port Blanks 4 £20 Air Filter + Backing Plate 1 £97 Throttle Position Sensor Jenvey TP1 1 £77 Jetronic female to Uscar male adapters Various Amazon sellers 4 £20 Total £1,388 Link to comment Share on other sites More sharing options...
7 wonders of the world Posted February 28 Share Posted February 28 Worth checking what pressure reg you have fitted as you can calculate the injector flow and requirement from that.. Inlet length should be checked on the rollers as there are good gains to be had here. If you opt for injectors in the throttle bodies then there's more expense with fuel rails and pico injectors. If you go to but Bosch green giants please buy from a reputable source as there are many copies out there. Link to comment Share on other sites More sharing options...
Support Team Shaun_E Posted February 28 Support Team Share Posted February 28 A good point from 7 Wonders - if you have the injectors in the TB instead of the stock position, the Bosch green injectors don't fit with a flat filter backplate so you need to buy the shorter pico injectors. Link to comment Share on other sites More sharing options...
JAL73 Posted February 28 Share Posted February 28 (edited) I am interested in upgrading my 420R to Jenveys and heard Nothampton Motorsport were one of the best in the business at doing this upgrade. Incl VAT they quoted me £2,042 in parts and 11 hours labour at £1,176 to install and map on their rolling road. It looks like 6.5hours of installation work and 4.5hours of mapping/ callibraiton. They recommended 45mm ITBs for under bonnet fitment. They quoted an extra £350ish for cutting a hole in bonnet to accomodate an extrnal air box. I guess an external box allows for colder/denser air intake and maybe to allow for bigger trumpets, but not sure how much extra performance this would give? My car currently starts and idles perfectly, has great low revs/ low throttle manners and I cant really say it lacks power, however I love the noise of ITB cars make at high rpm! As its a non-trivial amount of money I'd love to experience Jenveys before I buy. So if anyone in Surrey/ London area would offer a demo I''d be eternally grateful. Here's the breakdown of my quote (under bonnet mount) for those interested. Edited February 29 by JAL73 Link to comment Share on other sites More sharing options...
7 wonders of the world Posted February 28 Share Posted February 28 The above doesn't specify whether your looking at 45mm or 48mm TB's, the later would permit further upgrades cams or head etc without additional outlay with no adverse effects on your current set up. Link to comment Share on other sites More sharing options...
Drakman Posted February 28 Share Posted February 28 Is there an advantage to placing the injectors in the ITB's over the standard head location? Link to comment Share on other sites More sharing options...
JAL73 Posted February 29 Share Posted February 29 9 hours ago, 7 wonders of the world said: The above doesn't specify whether your looking at 45mm or 48mm TB's, the later would permit further upgrades cams or head etc without additional outlay with no adverse effects on your current set up. They suggested 45mm but that might be because I said I didn’t want to cut a hole in the bonnet (my car is SV body). Do you know what bhp or torque diffs 48mm offer over 45mm on a like for like comparison? Link to comment Share on other sites More sharing options...
7 wonders of the world Posted February 29 Share Posted February 29 I'm referring to the bore of the throttle body 45 or 48 I think they are referring to the air horn length the shorter 45mm ones sit inside the bonnet the longer 90mm ones need their own window Link to comment Share on other sites More sharing options...
Ainsley Posted February 29 Share Posted February 29 Why don't you want a hole in the bonnet, looks or extra cost ? Hole in the bonnet = cold air = more power. Also means they fit the best length trumpet, which has a direct effect on where in the rev range you get the power. Link to comment Share on other sites More sharing options...
Nigel B Posted February 29 Share Posted February 29 To my eye, Sevens don’t look quite right without an air filter cut out. But then I did grow up in the 80s, lusting after BDRs & 1700 Super sprints! Link to comment Share on other sites More sharing options...
Ainsley Posted February 29 Share Posted February 29 To me the cut out bit shouts "performance" 🙂 Probably sounds better as well. From the drives seat with the airbox on the left I bet you cant see it anyway ! 1 Link to comment Share on other sites More sharing options...
Drakman Posted February 29 Share Posted February 29 Can someone please let me know the part numbers for ITB mounted fuel injectors and fuel rail for use with the flat back air filter. I'm guessing either 250cc or 330cc injectors. Link to comment Share on other sites More sharing options...
graearea Posted February 29 Share Posted February 29 (edited) it certainly makes the car look a little more racecar/menacing/purposeful/etc having the airvent hanging out the side 😄 induction noise is increased which can be a bad thing with noise limits. it does sound mad at full blast. it sounds like it's trying to suck the earth into it! 😄 enjoy the braaaaaaps Edited February 29 by graearea 2 Link to comment Share on other sites More sharing options...
Ainsley Posted February 29 Share Posted February 29 *Orders Throttle Body conversion kit and starts cutting a hole in the bonnet* 4 Link to comment Share on other sites More sharing options...
JAL73 Posted February 29 Share Posted February 29 4 hours ago, Ainsley said: Why don't you want a hole in the bonnet, looks or extra cost ? Hole in the bonnet = cold air = more power. Also means they fit the best length trumpet, which has a direct effect on where in the rev range you get the power. Don’t want the hole for two reasons 1. I’m personally not a fan of the external box looks, prefer cleaner look for bonnet but each to their own 2. Noise - i understand that ITBs are noisier than single plenum, and even noisier if airbox is outside. I would be really unhappy if I spent a chunk of money on performance upgrades and then but then got black flagged for noise on track where you really want to unleash it all. Most tracks seem to be 101-105db static noise limit and I think I’m currently around 97/98db static on a factory standard single plenum. Link to comment Share on other sites More sharing options...
Ainsley Posted February 29 Share Posted February 29 (edited) Some of the through the bonnet ITB's are shrouded in a box to keep the noise down, some are just a filter sticking out, which I imagine are more noisy. When I was discussing this with Premier Power, they did advise their airbox solution to keep the noise down, its a sort of half / half. Edited February 29 by Ainsley Link to comment Share on other sites More sharing options...
graearea Posted March 1 Share Posted March 1 I've only been black flagged at bedford. if you don't pin it past the noise meter you're fine. Link to comment Share on other sites More sharing options...
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