I was just thinking that it would be great if someone such as Dave McClellan would use a chassis dyno, street driving, track testing, and emissions testing to evaluate the modifications that are typically performed on C4s. I know, many people can give all sorts of feedback about modifying Corvettes, but few of them have the knowledge that Dave or his engineering friends possess. I believe Dave could write an interesting and practical guide about C4 modifications. If I knew how to contact him, I would be tempted to lobby him about writing such a book.

 

Who do you think is actually going to pay for it?

The advertisers certainly will not.

 

I know, money is always a problem. I was just thinking wishfully.

 

vader86,

You can tell I'm on vacation because I am wasting time adding to a frivolous posting (of course, you could argue that most of my postings are frivolous ...). There's probably enough anecdotal evidence about common C4 mods that it would be a waste of valuable time and good money to do any formal testing at this point. In addition, the gang at Lingenfelter's has probably done enough testing to answer everyone's questions. Nevertheless, I would be interested to see the conclusions of a formal test that measured the effects of a K&N filter, MAF screen removal, cat-back exhaust, long tube headers, and even a three-angle valve job. Although variables such as temperature and humidity (among others) can affect the reliability of such testing, it might be enlightening to see the accepted mods put under the gun. By the way, here's an aside that raises issues about the value of many of the simple mods done to C4s: I read a book by three-time Formula One champion Niki Lauda in which he said that if one of the turbo McLaren engines that he raced in the early eighties was weak by 50 to 100 horsepower, he coudn't tell the difference (although the stop watch certainly could). That's a statement from one of the most sensitive F1 drivers of all time.

 

We have seen dyno tests on MAF, exhaust.

People have done the simple mods together and gotten about 5-10hp. My dyno results showed that gain from Bypass/K&N/MAF screen removal.

Tons of people here have done dyno testing on exhaust, and I know of one result where they tested all the popular catbacks against each other without changing anything else. They all give about the same, 10-15hp. Mostly in the 11-13 range and the bigger ones give a little more.

We have people with header results, though I can think of none who dynoed 1 5/8 vs 1.75" without changing anything. Its proven to give about 15hp on the L98 and about the same on LT1.

If the search is working you can find them.

 

I would pay for such an informative book. In fact I have, or at least I thought I did. Anybody read "LT1 HINTS and L98 UPDATES" from TPIS.They have an in house dyno and specialize in LT1 and L98s.So I just assumed from the title that it would be full of facts and stats of all the "mods" from free to high dollar.

Well, It was a huge disapointment. Their idea of a "LT1 HINT" was remove optispark, discard long block, replace with stroker, install optispark and dyno test.TA-DA......... you got 400+ HP.

Anyway, if somebody sold a book with dyno test of every little mod, I would buy it. :chevy