Hey guys, how we hanging? Just a heads up to watch your mail. Got everything cut (finally) and will be shipped out in a day or so. Thin metal is rare in our shop, unless you want it out of 1/2 inch or thicker...lol Had to wait till we got in some 1/8 inch material. Thats the thinnest we get. Hope you guys like...

Anyway, few more questions if you's don't mind. Don't worry, easy questions this time...

There are three cables going to upper plenum. Throttle, cruise, and (D-tent to tranny?). One thing I noticed when I drove car was there was a shift kit in tranny. But I would have to almost floor it to get it to kick down. Is there a way to adjust this so it kicks down quicker?
I ask because my ol'man has a '71 Nova SS show car with a 355 HO with all the goodies. He had something done to something under hood that made engine/tranny slam to a lower gear as soon as he gave it gas at cruising speed. His is a built TH350.

Now my question, what causes the tranny to kick down on my car and can it be adjusted?

Second question, what all engine performance hop ups can I get away with, without altering ECM? Thinking on some 1.6 roller rockers (appose to a cam), 58mm throttle body, and maybe a ring and pinion change. Maybe a 373 or so.

Third question, will changing the rear end gears mess with my speedo?

Thanks guys

 

Hey L98

I was wondering how are you doing with all that white stuff around you. Hate to bring this up to you body, but it was 66 here in OC, but the surf was only 1-2 ft - ankle to knee high and poor+ conditions! Any how, speaking for myself what ever scrap metal you have is good. I believe in recycling my scrap material ( believe me my place of biz tosses a lot of Al into scrap bin).

1) Regarding your tranny - 700R4. Unlike well known kickdown cable used in THM 350 and 400 transmission the 700R4 uses what is know as TV cable. Under no circumstance should you be messing around with this cable unless you fully understand what these adjustments can cause. In case of 700R4, and its cousin 200R4, use Throttle Valve (T.V.) cable for multiple purposes. It is very important to set up TV cable linkage properly to prevent damage to your transmission. The following is a quote from GM service manual:
"The TV cable used on the 700R4 (4L60) controls line pressure, shift points, shift feel, part throttle downshifts and the detent downshifts. The function of the cable is similar to the combined functions of a vacuum modulator and a detent cable."

2) Non of the engine mods that you have mentioned will do dam thing in terms of meaningful performance. Stock engine is chocked by restricted exhaust, tiny cam and lousy heads. Yes, I know, I will get in trouble for these comments, but I rather spend my monies where I get the biggest kick in pants. Your current L-98 (5.7L) has great potential, but you have to set a realistic goals before starting. Start with reading stickies in TPI forum. It is a long winter to plan this out.

3) Changing ring and gear will alter speedometer reading, but this can easily fixed by replacing the plastic speedo drive gears to compensate. It is a ten minute job to swap speedo gear.

//RF