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Search found 199 matches

by BLSTIC
Wed Oct 20, 2021 4:39 pm
Forum: Engine Tech
Topic: video on velocity and sound
Replies: 17
Views: 886

Re: video on velocity and sound

It seems like you have quite a bit of bowl fill. There's usually slow air on the bench in that area, do you see gains on the dyno filling that? I have always wondered why that filled area even exists. What purpose does it serve? And is it worth having it given the velocity improvements you get from...
by BLSTIC
Sat Oct 16, 2021 7:35 am
Forum: Engine Tech
Topic: Oddly broken piston
Replies: 10
Views: 899

Re: Oddly broken piston

Also a lot of drift cars will have an undersized turbine to try eek out every bit of boost threshold and response. That won't help detonation if that's the case.
by BLSTIC
Tue Oct 12, 2021 6:51 pm
Forum: Engine Tech
Topic: Unique Engine – More Power Needed
Replies: 26
Views: 1680

Re: Unique Engine – More Power Needed

I want to thank everyone with there feedback so far, in particular 'maxracesoftware' for all the time spent modeling. (BLSTIC I hope to see your analysis also.) A couple of comments on what has been provided to date: - Original valve size was 1.625 Int & 1.516 exhaust. Getting the port sizes up to ...
by BLSTIC
Mon Oct 11, 2021 12:10 am
Forum: Engine Tech
Topic: Unique Engine – More Power Needed
Replies: 26
Views: 1680

Re: Unique Engine – More Power Needed

FWIW, I'll put that engine into Engine Analyzer tomorrow at some point. It'll be fun.

P.S. What's the length on that inlet manifold? EA will want me to know that and I can't guess well enough from picture clues
by BLSTIC
Mon Oct 11, 2021 12:08 am
Forum: Engine Tech
Topic: Unique Engine – More Power Needed
Replies: 26
Views: 1680

Re: Unique Engine – More Power Needed

I would try 3.5 in collectors Isn't that a bit big? It's only a three-cylinder collector taking in 1.875 pipes with evenly spaced exhaust. The duration vs length equation probably works out that there's only one pulse going through at a time. That said, I don't know what I'd be trying to adjust it ...
by BLSTIC
Tue Oct 05, 2021 5:23 pm
Forum: Engine Tech
Topic: Dimpling a LS port
Replies: 106
Views: 4181

Re: Dimpling a LS port

Water itself is pretty crap at evaporating compared to hydrocarbons, even though it provides fantastic cooling when it actually does evaporate. But with modern high pressure injectors it could work for that purpose vs the in cylinder purpose it mainly serves now. The thing about that vs high fuel in...
by BLSTIC
Tue Oct 05, 2021 4:44 pm
Forum: Engine Tech
Topic: It's all about the FUEL
Replies: 64
Views: 2937

Re: It's all about the FUEL

Thinking about this a little more from the perspective of a street turbo car. Below the turbine spool rpm, one would need chemical oxidizer and fuel. Above the turbine spool rpm, one just needs higher octane to prevent knock. What’s the best solution here? Perhaps a dual injector setup with water/m...
by BLSTIC
Mon Sep 27, 2021 10:22 pm
Forum: Engine Tech
Topic: It's all about the FUEL
Replies: 64
Views: 2937

Re: It's all about the FUEL

A comparison of nitromethane to methanol reveals the following: Nitromethane Oxygen content = 52.4% Heat of combustion = 4529 BTU/lb Stoich = 2.21 Specific power = 2049 BTU/ lb air. Methanol Oxygen content = 49.9% Heat of combustion = 8589 BTU/lb Stoich = 6.47 Specific power = 1328 BTU/lb air. Sinc...
by BLSTIC
Thu Sep 23, 2021 5:38 pm
Forum: Engine Tech
Topic: How much swirl is too much swirl
Replies: 47
Views: 2249

Re: How much swirl is too much swirl

We didn't see any CFD modeling on our race engines back in 2004, but later I saw a simulation on a production engine that showed a dished piston allowed better tumble continuation after BDC. We ended up running a small chamber and a shallow spherical dish in our race engines; as many others had. Tu...
by BLSTIC
Wed Sep 22, 2021 5:50 am
Forum: Engine Tech
Topic: How much swirl is too much swirl
Replies: 47
Views: 2249

Re: How much swirl is too much swirl

Chopping the short-turn away, and making the roof line low, can create extreme in-cylinder tumble. We only did this for an experimental hybrid engine that was throttled by EGR percentage, and needed extreme in-cylinder mixing. What changes did you note from that experiment? I wanted to do this to a...
by BLSTIC
Sat Sep 18, 2021 4:03 pm
Forum: Engine Tech
Topic: Reading plugs, what's going on here?
Replies: 11
Views: 757

Re: Reading plugs, what's going on here?

ClassAct wrote: Fri Sep 17, 2021 10:40 pm The ground strap is ignition timing. The porcelain is the tune up. It’s certainly rich.
The car certainly has ignition timing... Would this indicate too much or too little advance?
by BLSTIC
Fri Sep 17, 2021 9:45 pm
Forum: Engine Tech
Topic: How much swirl is too much swirl
Replies: 47
Views: 2249

Re: How much swirl is too much swirl

I can't give you the measurements, but i know at least on a hemi combustion chamber swirl is better than nothing, but not as good as tumble. Excessive swirl tends to lead to inefficient combustion at high rpm. Mitsubishi Astron engines are a good example. Big valves, hemi, moderate flow, must be gre...
by BLSTIC
Fri Sep 17, 2021 9:37 pm
Forum: Engine Tech
Topic: Reading plugs, what's going on here?
Replies: 11
Views: 757

Reading plugs, what's going on here?

So my mate pulled these from his 95 Tahoe (factory 350 tbi) and it's a bit confusing. How is the ground electrode so clean when the rest of the plug is sooty? Is it being washed or something? No real symptoms, just not running very cleanly when cold (when comparing to our more modern cars, so it mig...
by BLSTIC
Sun Sep 12, 2021 8:34 pm
Forum: Engine Tech
Topic: Ram induction question
Replies: 11
Views: 739

Re: Ram induction question

Longer tubes does result in lower tuned frequency. But there are several harmonic lengths available for any particular RPM. The shorter ones have the wave traversing more times than the longer ones. You may be looking at a length where Chrysler product works on the 4th* harmonic, but if you lengthen...
by BLSTIC
Sun Sep 12, 2021 8:27 pm
Forum: Engine Tech
Topic: Porting With an Electric Die Grinder
Replies: 59
Views: 3019

Re: Porting With an Electric Die Grinder

I used a Makita *Battery* one for a turbo adapter. The nature of the tools available to me at the time meant I had to go from a 38mm hole to a T3 flange, twice.

3/10 Would not recommend. Car went really fast though...