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Search found 284 matches

by Rick!
Sun Jan 29, 2023 7:48 am
Forum: Chassis / Suspension / Body
Topic: Shaving/buffing tyres for endurance racing?
Replies: 4
Views: 100

Re: Shaving/buffing tyres for endurance racing?

No. Shaved tires do not last as long as street tires. How long are the races and what kind of budget do you have? Do you have access to test on the endurance track? My experience is that shaved tires will go around corners faster. Suspension mods will allow the car to corner faster. More engine powe...
by Rick!
Fri Jan 27, 2023 7:18 am
Forum: Engine Tech
Topic: Oil & Coolant Temp Correlation; Oil Sump vs. Bearing Temp Coorelation?
Replies: 4
Views: 261

Re: Oil & Coolant Temp Correlation; Oil Sump vs. Bearing Temp Coorelation?

Cruising down the highway, the oil will usually be 10-30°F above coolant temp. If coolant is 200°F, the oil should be 210-230°F. For the temp delta at the bearings, it's about the same so 230°F sump temp can expect ~250°F bearing temp at light load / cruise condition. This is in line with my experi...
by Rick!
Wed Jan 25, 2023 7:07 pm
Forum: Engine Tech
Topic: Toyota 22R valve lash.
Replies: 6
Views: 216

Re: Toyota 22R valve lash.

I had a 22RE for a long time last century. Exhaust valve sinks into the seat and intakes got loose. Every time I adjusted the lash (annually), I got a tad lower gas mileage. What did make noise is the timing chain. They need a new chain and tensioners after 125k miles as the rattling gets a little a...
by Rick!
Mon Jan 23, 2023 7:11 pm
Forum: Engine Tech
Topic: SwitchFire X pipe
Replies: 13
Views: 778

Re: SwitchFire X pipe

I find the Coyote exhaust note painful. I don't know how they came up with such an angry noise out of a 180* crank Coyote is not 180° but i agree, those things sound ragged. My bad, I assumed a Coyote was 180. The weird thing is when you drive one, it doesn't sound crappy. I rented a 5.0 Mustang tw...
by Rick!
Mon Jan 23, 2023 1:26 pm
Forum: Engine Tech
Topic: SwitchFire X pipe
Replies: 13
Views: 778

Re: SwitchFire X pipe

Simple application of destructive interference. 2% power gain is just removing the muffler, not because the design is "super cool" as Borla guy states. I find the Coyote exhaust note painful. I don't know how they came up with such an angry noise out of a 180* crank when a Ferrari makes such a beaut...
by Rick!
Mon Jan 16, 2023 7:28 am
Forum: Engine Tech
Topic: Exhaust system clearance
Replies: 5
Views: 328

Re: Exhaust system clearance

Where in the cart are we talking? Front just aft of the engine compartment? In the engine compartment? Or at the back by the fuel tank? In the engine compartment: probably needs shielding. Headers take up more space than cast manifolds and disrupt airflow going thru and down under the hood. Vents in...
by Rick!
Sun Jan 08, 2023 8:28 am
Forum: Engine Tech
Topic: Rod bolt tightening
Replies: 37
Views: 1806

Re: Rod bolt tightening

Clamped length is the important dimension as opposed to bolt length. If I bolt together two pieces of 16 gauge steel with a 4" bolt, the joint is going to vibrate apart or thermal cycling will loosen it quickly due to a lack of bolt stretch as a result of the 1/8" clamped length. Stretch, torque, an...
by Rick!
Wed Jan 04, 2023 8:03 pm
Forum: Engine Tech
Topic: Rod bolt tightening
Replies: 37
Views: 1806

Re: Rod bolt tightening

When you tighten a rod bolt to get the desired stretch how high of a torque reading do you get to achieve proper stretch? Does it ever go to 60-70-80ft.lbs. or more using the recommended lube? Calculating Stretch - note, stretch is directly proportional to clamped length. Calculating Torque angle t...
by Rick!
Wed Jan 04, 2023 3:35 pm
Forum: Engine Tech
Topic: Rod bolt tightening
Replies: 37
Views: 1806

Re: Rod bolt tightening

Bolt tensioning using torque is almost useless. Unless the components have been tested and verified regarding tensile,lubrication, and friction. Almost never possible with aftermarket components. Angle torque or stretch are the only methods that should be considered in critical areas such as an eng...
by Rick!
Wed Jan 04, 2023 11:50 am
Forum: Chassis / Suspension / Body
Topic: Caster Question
Replies: 3
Views: 294

Re: Caster Question

...and jacking, and steering wheel return, and possibly roll center (if a large enough change to a hard point is made), and KPI. One of the few things that may not change is Side View Swing Arm (SVSA) angle so front end anti-dive should stay pretty much the same. Changing one of the six main kinemat...
by Rick!
Sun Dec 18, 2022 7:31 pm
Forum: Engine Tech
Topic: Belt tension
Replies: 14
Views: 720

Re: Belt tension

Cog belts don't stretch much, if at all in operation, if there are lengthwise kevlar or carbon fibers in them. In fact, they tighten up in operation due to metal parts heating up and due to tooth - cog friction on the drive gear, with is usually the smaller one. Due to a fixed center distance betwee...
by Rick!
Mon Dec 05, 2022 6:59 am
Forum: Engine Tech
Topic: Cutting the O2 sensor wire...
Replies: 11
Views: 638

Re: Cutting the O2 sensor wire...

The ECU (EEC IV, or EEK!) will not see the O2 sensor switching at an expected frequency so it will stay in open loop and eat more fuel. It should also run at a higher spark advance which will give the impression of better performance at the risk of more pinging. If you want to mess around more, find...
by Rick!
Wed Nov 30, 2022 7:28 pm
Forum: Engine Tech
Topic: Benefits of 4-port water bypass on a SBC?
Replies: 173
Views: 11652

Re: Benefits of 4-port water bypass on a SBC?

Heat exchanger calorimetric curves knee out in two ways: First is that there is only so much internal surface area to conduct heat from coolant flow to be convected to the atmosphere, hence, after some BTU value, more coolant flow does not produce significant more heat rejection. Second, holding coo...
by Rick!
Wed Nov 23, 2022 7:04 am
Forum: Engine Tech
Topic: How will you go faster?
Replies: 294
Views: 8416

Re: How will you go faster?

I know you don’t like thinking outside the box with equations but Tractive effort force = wheel power / velocity So 400 hp (298,000 watts) at a speed of 60 mph (28.7m/s) will generate a tractive effort force = 10,383N (22,800lb) Last time I checked, 1lbf = 4.448N, so your calculation should be clos...
by Rick!
Thu Nov 17, 2022 8:01 am
Forum: Engine Tech
Topic: How will you go faster?
Replies: 294
Views: 8416

Re: How will you go faster?

All these "what-if" can be tested in Quarter Pro, which came in the ST bundle a few years ago. All the "air" related factors can be calculated using the "Motorsports Standard Atmosphere" and using the Correction Factor. It's basically a modified version of J1349. A proper weather station is requisit...