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Touge

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About Touge

  • Birthday 01/07/1980

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  1. I agree with Larry re:engine swaps. I just can't stomach the thought of putting a GM product in a classic Japanese sports car. Now a VH45DE would be right in my way of thinking. However, I do love the sounds of a screaming straight-6. For me, it conjures up images of vintage Le Mans and Steve McQueen's XK120 tearing ass through the canyons or along the PCH. A 90 degree V8 makes me think NASCAR unless it's mounted behind the seats in a GT-40. My apologies to the OP for the hijack. My advice would be to read up on how motor geometry affects the rest of the engine. You can always email Larry staff@theoldone.com. He's usually pretty busy but you will get an answer back.
  2. I actually discussed building an L-series with Larry back in 2006. The plan was to use and LD block and use an L24 crank so I could run a long set of rods. Larry was going to weld and reshape the chambers and install the pistons to re-create one of his old NASCAR engine designs. With the right valvetrain I could make power all the way to 10,000 rpms. He also joked that for all that work I could just do an LS swap and be done with it.
  3. That run was on 93 octane. I've seen this motor in person in Larry's civic hatchback. It's a nasty street engine not some road race special. Larry told me he shoots for the most total amount of flow for the entire amount of time the valve is open not just peak flow numbers. There's a lot of neat stuff that isn't listed in the article on that engine. For example, there a splash guards inside the block to keep the oil draining back to the pan from splashing onto the crank. Larry also has load cells mounted against the cylinder liners and his ECU will pull the timing back when the cells measure any cylinder deflection. He also uses some tricks that you see on streetbike engines. Endyn also used to be big in NASCAR and Pro Stock before Larry got sick and had to take a break. Larry did the heads on Bill Elliot's car when he set the top speed record at Daytona in the early 80's. Needless to say he's getting the call when I build my engine Honda B motors are amazing. The ITR motors are great right out of the box but all the other B engines have as much potential waiting to be unleashed. My old Civic(a heavy ass coupe) had a plain non-vtec B20 out of a CR-V. The only mods I did was a thinner head gasket, Integra intake manifold (deburred and portmatched to the TB), cheapo header, CAI, exhaust, and a reflashed ecu. Lots of fun.
  4. Well my memory failed me. Larry's motor made 299hp and 189tq. Scroll Down for the dyno slip Here's the link to the build-up of the engine: Link
  5. Just to add what I've learned in talking to and reading what has been put out there by people much smarter than myself as well as what I've learned in my own tinkering over the last 10 years. Bottom end geometry does alone dictate an engine's powerband, peakiness, etc. Even basic generalizations are easily disproven. Take the Nissan SR20DE and the Honda B16, archetypes of the small displacement performance engine. Both are DOHC, 4 cylinders, and very close in output but are greatly differing powerbands. The SR20 makes gobs of torque all through the midrange but runs out of steam on the top-end. The honda is almost the opposite. It does nothing until 5000rpm and then charges all the way to the 8000 rpm redline. The odd thing is that the Honda is the under square engine although it does have a 1.75:1 R/S ratio. The 85x85mm SR20 is the torque monster against conventional wisdom. R/S ratio will dictate the max rpm your bottom end can sustain. Longer rods slow the rate at which the pistons accelerate away from TDC and BDC. Long rods also increase the amount of dwell time at TDC which helps with cylinder filling at higher rpms. Cylinder bore wear will be reduced due to reduced piston side loads. The trade off is a taller engine, more reciprocating weight, and reduced cylinder filling at low rpms. The caveat is that all these factors, except for piston speeds, are affected by the rest of the engine components. Larry Widmer at Endyn, who has built some amazing engines (like a 300hp, 285tq, 2.0l Honda B-series), feels that 1.75:1 R/S is a good compromise for a NA street engine and anything below 1.6:1 may benefit from a reduction in stroke to allow installation of a longer rod package. With all that said he is still in favor of getting as much displacement as possible and tuning around it for the performance level you desire. F1 is not the be all end all of engine performance. The rules of F1 tend to dictate engine configuration. The ban on turbos means the engines have to spin to high rpms to make power. High rpm dictate a large bore (for bigger valves). The engine can't be too tall because of aerodynamics so you have to reduce stroke to keep piston speeds down. The added benefit is reduced pumping losses. At 12000+ rpms valvetrain weight and friction becomes a factor. Thats why you don't see 5-valve per-cylinder F1 engines. Almost all are 40 valve, V10's. Honda and BMW were both planning on fielding sub 2.0l turbo 4's when the turbo ban went into effect in the early 90's. As you can see, everything is a tradeoff. When I build my engine, I think I'm going to run an L24 crank in the tallest block I can find (LD28?). I punch the bore out as far as possible and fit it with ITB's, big valves, and a big cam. I'll fit an eaton supercharger making 5-8psi to make up for the lack of low end. My Z is just for my own personal enjoyment and doesn't have to conform to any class restrictions (except my wallet). History has shown that big, low rpm engines are just as viable as small high rpm engines. Sorry for the ramble on.
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