Boost Performance UK - Blueprinted corvette camaro ls1 ls6 engines, ls1 performance parts-custom, ford and scorpio specialists, rover, zetec, turbo engines. We specialise in custom built, Chevrolet LS1, Rover V8, Ford Zetec and Ford 24v Cosworth. 

Products > Ford 12v & Cosworth 24v BOA & BOB. Now available, H/D timing chains (BOA & BOB) and cylinder head stud kits for the 24v engine, see below. BOA 24v tensioner blade sleeves in stock - £65 .Tensioner arms/blades - £100. Email me via the 'Contact'page to order parts!

"Boost Performance". Only Boost Performance can offer Cosworth 24v Turbo cast iron exhaust manifolds. Built to endure.

Ford Cosworth Engine
Ford Cosworth Engine

Cast iron lasts much much longer then fabricated items, it's extremely tough and durable which is why car producers use it. It won't twist, flex, warp or crack like stainless steel. These manifolds have been designed for retrofit engine installations. We can offer them with a 4 bolt per flange fixing if required. The turbo/s can be mounted onto the manifold (depends on turbo type) or remotely using fabricated elbows or extensions.

We supply adaptor flanges for remote locations if required. A single 2 into 1 turbo exhaust manifold (pictured at the bottom of this page - can be purchased for use with single turbo diy installations for £265. Both exhaust banks feed into one t3 frame turbo located on the passenger side of the engine.

PRICE: £200 each or £380 a pair.

Our high strength Gen 2 forged turbo pistons

Ford Cosworth Engine

All our engines are assembled using only premium quality custom made forged pistons designed to our own specification, fitted with race type piston rings & taper wall gudgeon pins. The internal components are individually balanced and weight matched to a fraction of a gram where required and are significantly lighter then standard. The crankshaft is then dynamically balanced by machine. This produces a free revving engine with less internal stress, that idles smoothly.

We still retain the Cosworth 24v crank (we offer a tuftriding service) and con-rods but precision billet or 'H' beam steel rods are available to special order as is our girdled sump assembly which strengthens and unites the lower block and main bearing caps.

Our turbocharged engines with big-bowled pistons usually have a compression ratio of 7:1 or 8.5:1, whilst our normally aspirated engines with true flat top pistons have a compression ratio of approximately 10.5:1. All our engines are fitted with deeper valve cut-outs in case of over revving, also allowing the use of after market camshafts.

We can also build these engines with bushed little ends thus allowing 'fully floating' piston fitments, with pin retention by circlips. Please note that we don't sell piston kits alone. These pistons are specific to each custom engine build we undertake.

Custom, cosworth 24v plenum, BOA or BOB available. BOB throttle body manifolds also available.

Ford Cosworth Engine

Click thumbnail to enlarge image
Boost Performance developed this plenum assembly for 'blown' or n/a applications. It can be supplied ready to accept stock plenum fitments and bolts on in the original position. We can offer a twin throttle body version. Air can now flow freely into the engine via the stock throttle body assembly as there are no internal restrictions. We provide threaded holes for you to mount a throttle cable bracket. The internal volume can be reduced with packers if required. The base plate can be purchased separately and used as an adaptor to mount the BOB runner assembly or even a supercharger such as an Eaton.

Height is the same as stock and the throttle can be mounted vertically or tipped forwards. Trumpets can be fitted if required. Cosmetically it should be painted or coated but we supply it 'as is' unless asked.

Your logo can also be added to the lid.

PRICE: £500 - £550 depending on fitments

24v Shortened Cosworth Bronze Aluminium Valve Guides

Ford Cosworth Engine

For turbo or high performance road/race engines engines we produce shortened bronze silicon exhaust valve guides. They transfer excess heat from the hot exhaust valve to the head. These require reaming in situ for final valve to guide clearance. We can do this for you if you like.

PRICE: £10 each or £20 installed

Gen 2 Turbo Piston

Ford Cosworth Engine

Our forged, Gen 2 low compression, high strength turbo pistons feature a turbo specific ductile ring pack, stronger yet lighter wrist pins, deeper valve cut-outs and they also feature a performance enhancing tighter 'squish' clearance. These pistons are designed specifically for 'boosted' applications and bespoke engine builds.

V6 Integral Girdle

Ford Cosworth Engine

We have successfully developed a precision CNC machined billet aluminium sump girdle which is integral to the sump. This is for high rpm/ high torque engines. It's function is to tie 'ALL' of the the main bearing caps to eachother, the sump and engine block. This prevents cap shuffling and fretting because every cap is properly supported and held captive.

The girdle unites, stabilizes and braces the main bearing caps as well as the engine block. This is a bespoke item, machined to suit each engine we build. The picture shows a modded girdled sump with turbo drain tubes for a tarmac race car.

PRICE: £800 (includes fitting kit).

We have also developed a more affordable, heat treated 'cast' alternative to the above billet machined item which is suitable for 4wd as well as 2wd high revving road engines or forced induction.

PRICE: £600 2WD, £700 4WD (includes fitting kit).

This may be offerred on an exchange basis for DIY fitment. We need your sump to do this and some fettling may be required by you for final fitment.

Cosworth 24v BOA Cam cover gaskets.

We've developed a 'race proven' solution to those tired leaking O/E 'factory' gaskets. We produce gaskets that are easier to fit then other brands on the market and ours work. Our design copies the race proven FBE race engine gaskets. Our gaskets are wider then the original items and are completely flat which is how we get a better seal. We supply 4 hard resin inserts to seal the front of the heads and the gaskets lay over the top. No leaking, squishy bungs here.

PRICE: £65 including UK postage

24v BOA-BOB Timing cover gaskets in stock!

We recently started producing these ourselves from new tooling as they're no longer available from Ford. If you mistakenly use a BOB gasket on a BOA block you could end up with an open oil gallery and wreck your engine on startup! Buy the right gasket for the job.

PRICE: £10 including UK postage

24v BOA/BOB. Engine inspection or rebuild service.

We will dismantle your engine and remove the crankshaft and internal parts. After inspection for damage or wear we advise on a course of repair or improvement. We repair and rebuild stock engines as well as building custom engines and we also carry out some mechanical repairs in situ.

PRICE: From: £180. Rebuilds from £700.

Cosworth 24v, BOA-BOB Timing Chains!

We offer O/E chains for either engine as well as a budget option.

PRICE: £350 O/E including UK postage. Budget, £200.

New BOA tensioner blades and sleeves available. POA

Cosworth 24v, BOA-BOB Head stud kits!

We order these studs, manufactured to our specifications using high strength 12.9 grade steel. These allow superior head clamping and are reusable. These are for any high performance engine build. The ARP nuts are also 12.9 grade.

PRICE: £300 including UK postage

24v BOA/BOB Piston ring sets now available.

We have sourced an aftermarket high performance ring pack that fits the 24v engine. This is a custom made ring pack. These are for standard bore engines.

PRICE: £300


A Cosworth 24v twin turbo race engine, has been developed

This race engine was installed in a TVR competing in the TVRCC challenge championship for a full 2 seasons racing. We expect a reliable 500 plus horsepower after winter testing. The engine uses our forged Gen 2 pistons, custom rings and pins but most importantly it has our unique billet sump girdle installed which helps to keep it all together when revving to 7000 rpm and beyond for extended periods. Short/long engines can be built to customer specifications. We are now using our own design, maximum strength, forged pistons, designed specifically for forced induction. We have a set of these installed in a customer's engine being developed to produce well over 600 hp, the goal being to challenge TT's famous Minker on the dyno.

Our custom built TVR Sagaris 3.1, Cosworth 24v twin turbo race car has been track proven.

Our high boost race engine was successfully installed into another TVR also competing in the TVRCC challenge championship. This car proved to be 100% reliable in a competition environment whilst producing huge power and torque.

Boost 3.1 litre N/a or Turbo conversion:

Short motor rebuild includes full chemi-clean of parts, Gen 2 forged pistons, performance ring pack, lightweight pins, engine rebore and hone, new shells, hand balance, dynamic balance & a blueprinted bottom end. Can be upgraded to coated Gen 3 pistons and a Total Seal gapless ring pack. We offer a tuftriding service for crankshafts and camshafts if required.

PRICE: £2'900. Long engine 'forged' build from £4'300

Our new Gen 3 Turbo Pistons feature Ceramic coated crowns & are also supplied with a Hard skirt coating, with a Teflon seal. This is the ultimate piston protection available for a hard running normally aspirated or turbo engine.


Ford Cosworth Engine

Ford Cosworth Engine

Ported heads/valve seats are available to different specifications

Ford Cosworth Engine

Head porting, blending with bowl modifications, per pair. PRICE: £450
34mm turbo exhaust valves, stellite seats. PRICE: £30 each
Oversized turbo exhaust valves & seat inserts, fitted. PRICE: £POA
Bronze exhaust guides. PRICE: £10 each

Custom made 'H' beam steel rods are available to order £1850. We can supply titanium rods at 3-4 months notice. Billet Crankshafts available to order. Fully machined, Cast Iron SG Nodular turbo exhaust manifolds (as picture, top of page) per pair.

PRICE: £380

Blockhugger manifolds

Ford Cosworth Engine

Blockhugger manifolds suitable for installations where the Cosworth 24v engine has been transplanted into a tight engine bay. A perfect solution for TVR's! These could also be used to remotely mount a pair of turbochargers. You will have to provide 2 short straight downpipes to connect these to the exhaust system and some fettling and fabrication work may be required.

PRICE: £480 a pair

We also offer an alternator relocation/fitting kit with belt. This may not suit engines with PAS.

PRICE: £150

Customer Project Cars

Ford Cosworth Engine

Ford Cosworth Engine

David Whites Gulf Escort

Ford Cosworth Engine

Maddoldbuggers supercharged 24v

Genghis's 2.9 12v turbo currently making over 517hp & 540 lbs/ft at over 20 psi boost.  There's lots more to come!

Ad's 24v Sierra.

Ade's 24v Sierra

Seans 24v Capri

Sean's 24v Capri


Ian's 24v