Search found 196 matches

by gottago
Tue Feb 13, 2018 1:29 pm
Forum: Propane Forum
Topic: 454 efficiency - Maximum CR
Replies: 72
Views: 1219

Re: 454 efficiency - Maximum CR

It would be nice to be able to test all the different parameters and combinations of parts we think of and talk about. Unfortunately it is a fair bit of work and doesn't usually work out that way. I try to get people talking about what they've done and the results they experienced when I run into so...
by gottago
Tue Feb 13, 2018 12:47 pm
Forum: Propane Forum
Topic: Whats wrong with this turbo setup?
Replies: 5
Views: 69

Re: Whats wrong with this turbo setup?

Its a good starting point imo, cheapest and easiest way to get it going and see what it does. One ohg 450 with one x1 converter gives you a bit more than a single impco setup. Work out the bugs and modify from there if need be.
by gottago
Mon Feb 12, 2018 1:34 pm
Forum: Propane Forum
Topic: BLOS mixers and turbos
Replies: 2
Views: 34

Re: BLOS mixers and turbos

I don't see why not from looking at how they work. There used to be some European sites with better information on the blos setup. Do you have one running now in na form?
by gottago
Mon Feb 12, 2018 1:17 pm
Forum: Propane Forum
Topic: 454 efficiency - Maximum CR
Replies: 72
Views: 1219

Re: 454 efficiency - Maximum CR

If my thinking on this is correct, it would make a stronger case for using a bit larger volume 'airflow components'. For example, larger intake port volumes, perhaps an Rpm 'air gap' style manifold as opposed to a smaller one, twin mixers to feed it all, etc... And it would also help explain the lo...
by gottago
Mon Feb 12, 2018 1:02 pm
Forum: Propane Forum
Topic: Whats wrong with this turbo setup?
Replies: 5
Views: 69

Re: Whats wrong with this turbo setup?

You are asking most all the right questions dayzed. The ohg is good for a few more hp than the impco but probably only up around 360. I've teed two converters in series to one mixer before. No diff really but that was with both running off one lockoff. I'd go with the single/single setup and see how...
by gottago
Fri Feb 02, 2018 9:57 pm
Forum: Propane Forum
Topic: 454 efficiency - Maximum CR
Replies: 72
Views: 1219

Re: 454 efficiency - Maximum CR

Makes me wonder if maybe it's a mistake to place too much emphasis on the importance of needing very small ports to have enough velocity for a fun daily driver.... As a side note, but relevant to this thread, when the stock small chamber heads went bad, I put some 454 heads on with similar size por...
by gottago
Wed Dec 27, 2017 1:45 pm
Forum: Propane Forum
Topic: 454 efficiency - Maximum CR
Replies: 72
Views: 1219

Re: 454 efficiency - Maximum CR

The cam dyno simulation I posted was an example of what you would have to do to get a broad car like power band from a small peanut port head in a bbc. Just showing its possible by using an extra 20% ex duration. But there is a downside to just making what you have work as opposed to selecting the p...
by gottago
Mon Dec 25, 2017 2:40 pm
Forum: Propane Forum
Topic: 454 efficiency - Maximum CR
Replies: 72
Views: 1219

Re: 454 efficiency - Maximum CR

Always a good idea to try and match up the parts that go into making the entire combo first on paper. One little thing like the availability of high compression pistons for one head but not another can be a deal breaker. I went for a ride in a dually bbc vortec this past week. It was a tower, 13 mpg...
by gottago
Thu Dec 21, 2017 1:03 am
Forum: Propane Forum
Topic: 454 efficiency - Maximum CR
Replies: 72
Views: 1219

Re: 454 efficiency - Maximum CR

Oh I'm a believer.. The fuel mileage side of things rarely gets mentioned in tests like that. Too bad, its another deciding factor. 5mpg more over the course of 100,000 miles = xxx Anyways, looks quite possible to get the power in the ball park, just need the fuel mileage to fall in line. In the cam...
by gottago
Wed Dec 20, 2017 2:19 pm
Forum: Propane Forum
Topic: 454 efficiency - Maximum CR
Replies: 72
Views: 1219

Re: 454 efficiency - Maximum CR

That is a good start point for looking at the vortecs. The way the factory did things was all for a reason. Meanwhile, over on the speedtalk forum as of late, a list of links to camshaft design factors. Old and new... Some interesting points including on the split duration /ex flow theory.. ... http...
by gottago
Tue Dec 19, 2017 9:24 pm
Forum: Propane Forum
Topic: 454 efficiency - Maximum CR
Replies: 72
Views: 1219

Re: 454 efficiency - Maximum CR

When you have an engineering department like GM, the newer parts models should definitely be looked at. I'll have to do some reading up but if the bbc vortecs do as well as the sbc, they are in the running imo. They can produce power and mileage. How much would the cam specs need to differ? I'll do ...
by gottago
Tue Dec 19, 2017 12:27 pm
Forum: Propane Forum
Topic: 454 efficiency - Maximum CR
Replies: 72
Views: 1219

Re: 454 efficiency - Maximum CR

The bbc is one engine that I have no experience with. Been doing some reading though and do plan on one in the not too distant future. I really like the vortec heads on the small blocks but will have to research how they respond on the bb. The more modern fast burn chambers seem to be the way to go ...
by gottago
Mon Dec 18, 2017 5:29 pm
Forum: Propane Forum
Topic: 454 efficiency - Maximum CR
Replies: 72
Views: 1219

Re: 454 efficiency - Maximum CR

The peanut port is probably too mileage oriented. Maybe suited for an ultra low rpm application. The vortecs have decent reviews from the street performance guys. I have only used them in small blocks but they have a fairly good fast burn closed chamber and the ports flow well into mid range at leas...
by gottago
Mon Dec 18, 2017 4:04 pm
Forum: Propane Forum
Topic: 454 efficiency - Maximum CR
Replies: 72
Views: 1219

Re: 454 efficiency - Maximum CR

The question then becomes, is the amount of torque produced by the suggested cam installed in a high compression bbc suited to the vehicle and to what the driver wants? Wide lsa is the easiest way to get a wider power band without increasing duration to the point where the idle gets lumpy and fuel m...
by gottago
Sun Dec 17, 2017 12:30 pm
Forum: Propane Forum
Topic: 454 efficiency - Maximum CR
Replies: 72
Views: 1219

Re: 454 efficiency - Maximum CR

The heads pistons and cam intake close point should be looked at all together as a complete system. The bbc just by virtue of its size will produce torque quite easily. My experience with a 104 lsa camshaft in a high compression sbc showed me how easy you can get neck snapping low end torque. Respon...