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Following the end of the 2005 season the engine now sports a fully flowed Koehler Nitrous Injection system
Having played around with the car a bit in the UK Street racer series, I ended up achieving a very creditable 11.63 @ 117mph with a 1.59 60ft for what was basically still a stock street car which made it the quickest LS1 engined car in the UK at the time over the ¼ mile (if you know different let me know) As with most people hooked on drag racing, I now needed to go faster; it was time to up the anti a bit and look to see where else I could use the car in street form and keep the heads up style of racing that I prefer.
The obvious choice was Street Eliminator UK (formerly known as Custom Car Street Eliminator) a race series for street legal i.e. taxed, insured, MOT’d cars, that also involves a qualifying cruise at race weekends to ensure that the entries really can be driven on the road.
Cars in this series are regularly running into the mid and low 8 second zone at speeds upto 180 mph – more than quick enough to see off any of the exotics that you normally see on Jezza enthusing about on Top Gear. To compete I would need to make some radical changes to the existing car.
The LS1 engine originally fitted to the car is a great tool, providing 320+ hp in stock form and quite easy to get up to 550-600 but that wasn’t going to be enough for what I had in mind. While its been about in its current form for nearly 10 years now and 7 years in the F body platform, its still not a widely used engine in drag racing by anyone wanting to run faster than 9.99 – that’s not to say it can’t be done but its expensive.
So sadly the LS1 and gearbox was extracted and sold to another SRS competitor and Peter Knight of Knight Racing Services was contracted to build an engine with fairly stringent performance features. It had to be driveable on the road, not just capable of completing a Street Eliminator cruise, but something that could be used every day if required; it also had to be able to perform into the 8’s when called upon. I wanted the best of both worlds and left Peter to come up with an engine design that would do the job. Going against the trend for turbos that are becoming prevalent in streetcar competition, I decided to go for nitrous as the power adder simply for cost more than anything else - the turbos will be coming later but the current budget just didn’t stand up to the extra cost this year. To add to the mix it also had to be a small block, as fitting a big block would involve some serious remodelling of the front end, which again, was a bit more than the budget could cope with at this stage.
After talking it through with me and getting a firm understanding of what I was after, Peter emailed me an engine spec that he thought would do the job; a 434 ci sbc using top quality components throughout made it a very stout engine. Given the compatibility issue of some of the components it was a complicated and difficult engine to build but some good numbers were expected, in the region of 700bhp n/a. Delivery was anticipated in January but as testing was unlikely before March there was no great hurry so the bits were put on order. One change that would have to be made to the car to accommodate the new engine was to change the hood as the tall deck block plus intake plus carb was not going to fit under the stock steel hood so a call was put into Glasstek in the US for one of their lightweight fibreglass cowl induction hoods with a 4” cowl.
I found out that a slight miscalculation here was to bite me later.
After a bit of further discussion with Jon and Peter I changed the spec of the cam to a nitrous grind on the basis that it seemed pointless to produce an engine that would perform n/a but be raced with gas. I accepted I’d have to forego a bit of torque and hp n/a but the extra gain with nitrous would be worth it. Unfortunately this backfired on me a bit (pardon the pun) as it took a bit longer to get the particular grind we wanted but eventually all the bits arrived so that Peter could start building the engine once all the machine work was finished.
I arrived at Knight Racing Services to see the engine already mounted on the dyno and Peter walking towards me with a coffee – quality service. As well as being very nice people to do business with, they are the only engine manufacturers in the UK to have a Superflow 901 dyno that can handle an engine producing upto 2000bhp. This is the dyno that Andy Frost uses when testing his engine so it is well upto the task and used to seeing some big number making engines.
Malcolm was putting the finishing touches to mine as it sat on the test rig and double checking the settings and fittings etc. Unfortunately the bracket for the vacuum pump hadn’t arrived with the kit itself so we had to run without it. I stood watching them set it up thinking “I could leave here with a grin a mile wide or” …no, the alternative didn’t bear thinking about. With everything ready Peter took over the controls at the console while Malcolm checked the timing, I was so excited by now I didn’t even check the initial timing figure but I think it was around 30 degrees. It started straight off the button, phasing was spot on, no hesitation, no coughing, just a satisfying V8 bellow. After a quick pull we shut it off to check the lash; very little movement there but just enough to warrant an adjustment. So Peter says “right then, lets see what we’ve got”
A pull upto 5000 saw some very good figures spring up on the dials, an easy 500+hp plus torque deep into the 400s. An adjustment of timing, another couple of degrees, and away we went again running it upto 5000 again and then to 6000. It definitely liked the bit of extra timing as the hp and ft/lbs both showed a good increase and the engine sounded really strong.
Another small tweak to 34 degrees and the figures were starting to shock me; we were both expecting a drop in hp with the change to the cam but the engine clearly had ideas of its own because we were looking at figures deep into the 600’s and over 550ft/lbs.
Another tweak to 35 degrees and off we went again; 5000, 6000, 7000. The noise was terrific; sounding just like a beefy V8 should sound like. And there we had it – 688.1 bhp @ 6400 and 602.9 ft/lbs @ 5400 and a really good torque curve– without the vacuum pump and a nitrous grind cam - and before we’ve hit it with any gas! A quick adjustment of the timing confirmed that Peter had the timing on the money and that Chuck Nuytten knows his stuff when it comes to carburettors.
I think its fair to say that we were all a bit surprised at the figures it produced, especially me. It had me thinking what would it have produced if I’d stayed with the original spec cam?
After fitting the NOS Big Shot system with the smallest 225 jets we got ready to run it up again. Rather than wasting lots of nitrous, Malcolm prefers to run the engine up to rpm and then take a series of “snapshots” using the gas at specified rpm levels; in this case 5000, 6000 and 7000. With the timing receiving a conservative amount of retard for safety and with Malcolm now at the controls, me with the nitrous switch and Peter in the cell with the engine, in between the two flexible exhaust pipes, we were ready to go again. Malcolm gave me the thumbs up when to hit the gas so Pete could open the boost valve in the cell manually, not a position that he looked to be very comfortable with. One second after hitting the nitrous button I could see why! Stood immediately behind the headers in between glowing red hot pipes and a roaring engine is not fun – unless you’re watching from the other side of the window.
At 6000 it produced 964 bhp and 906 ft/lbs @ 5000. Good enough for me and fantastic numbers to get out of a small block Chevy and a great demonstration of the skills to be found at Knight Racing Services.
The engine has been sent to WRE for fitting and is installed in the car ready to test in June. I hope to compete in 3 or 4 rounds of Street Eliminator this year to find my feet with the car, pick up a bit more race craft and just generally watch and learn – but also have a lot of fun on the way.
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