Blake-73

What is the best sprak plug for my 73 383 cid, with 041 cast heads (64cc) from 1969?

Blake-73

Jvette73

I like AC Delco Rapidfire plugs. so far

stay away from Bosch platimun


[Modified by Jvette73, 10:22 PM 11/30/2001]

Captain Morgan

Why?

Blake-73

You know I've got the Bosch platinums now and I think it is causing me trouble.

How do you like the 200R4 you got? I am trying to decide between it and the
700R4. 200 looks easier to install. What's your thoughts?

Blake

73 LS-4

I've gotten to really like NGK's, I've run them in normally aspirated and nitrous applications, they come in a wide variety of heat ranges as well to suite almost any need.

:cheers:
Pat Kunz

Chris Fowler

I switched over to the rapidfires.

I don't know that I can really tell any difference over the normal AC Delco plugs, but I can't say that they cause any problems.

Rockn-Roll

I've run Bosch Platinums in all my rides and they perform great in my vette. Actually, any platinum plug would be better than other plugs...why? Cause platinum is a catalyst for combustion...you get a more complete burn.

Do the science before selecting...don't ask the salesman.

Jughead

I've been using Bosch Platinum since they first came out about 15-20 years ago. Never had one foul! I've used them in V-6's and V8's.

If I have an ignition problem, I know to check the plugs last, and so far I haven't had to check them! :D

Blake-73

A friend of mine runs AC 45 plugs. Anyone have god luck with these?

Blake :cool:

Jvette73

Bosch plugs worked fine for me however, in my case, they wore and went bad long before the should have. If you look at the tip of a new bosch plug you will see that the electrode is flush with the insulator. Its the tiny little dot in the middle. Well, on mine that little tip began to burn out up into, and leave a recess in the end of the insulator. This was creating misfiring. For the price I paid for these plugs, they didnt last much longer then standard ones.

One thing about standard AC plugs is some of them are made in a "comercial grade" as well. They have a beefier design with thicker electrode and insulator. Check one out at your parts counter and compare it to the standard AC. Just add a CR in front of the standard plug# i.e. R43TS becomes CR43TS. ive used these and like them too.

Blake-73, what tranny do you have in your car now? Im checkin the archieves for previous posts ive made on the subject. There are a few other members using the 200R as well. If I cant find the other posts, ill fill you in.

Jvette73

Blake, The 200R is a much more direct bolt in swap if you're changing from a TH400. I believe that all automatic equiped 73's came with the TH400. Does yours still have the 400? When a debate comes about between the 700R and 200R the only negitive thing people say about the 200R is that its weaker. I dont totally agree with this notion because the pro tranny builders say both thannys, the 200 and the 700 can be built to handle about the same amount of power and tq. I love my 200R and am glad I went with it. Here are some reasons I went with the 200. Keep in mind I swapped out a TH400.

1. The 200 is same length as the Th400.
2. Original crossmember was used unmodified.
3. exaust did not need modification.
4. a yoke change is needed but driveshaft did not need to be cut.
5. the 200 is lighter then the 700 and has lighter internals drawing less power loss to the drivetrain.
6. the gear ratios are closer range on the 200. no big jump between 1st and second like that of a 700.

After looking at all these advantages, it was not hard for me to go with the 200R. The 200R works great with 3.90 gears. Good acceleration and cruising revving 2250rpm@70mph locked in 4th.

Blake-73

Thats for the info...I am really leaning toward the 200r4 myself. Did you get yours form bow tie?

Blake

Jvette73

Yup got it from BTO. Tranny&convertor(2200stall). Also got thier TV cable kit and dipstick tube, toggle switches, in line filter, driveshaft yoke, pressure gauge. The plastic inspection cover they sell doesnt fit. The stock steel TH400 cover will work when holes in cover are re-drilled. more info on the tranny swap and dist info coming..time to go eat

Blake-73

If you do not mind me asking, how much $$ did the trans swap cost after it was all said and done?

Blake

Jvette73

Blake-73, heres a earlier post on my tranny swap. I did some things, then undid them and did them again. Its a long post. Pretty much what I went through is there. http://forums.corvetteforum.com/zerothread?id=139904


Heres some other links I used to help me with my mods. http://www.drwtransmission.com/thm_200-4r.htm
http://www.g-body.org/tech/tranny/200_700.html

http://www.angelfire.com/on/geebjen/timing.txt

http://www.prestage.com/carmath/calc_Gears.asp

DP77Vette

I know this may sound stupid, but I've got better and longer service out of Autolite plugs(FoMoCo) than any others. I ran them in my Vette for about 2 years, they still looked good, but I changed to AC (Genuine GM :rolleyes: ). Have put in 2 sets in 6 months. :mad Going back to Autolite soon. Tried Bosch in a 4.3 V6, maybe a year. Ran Champion in a 327/475 hp engine, :cry changed every 3 to 4 weeks when adjusting the valves.

I worked for Autolite 7 years making the things, I know the quality is good. Plus I remember making the metal shell for other brands too. By the way, we always heard that NGK stood for NO GOOD KIND...

Jvette73

I too have also had good expierence with Autolite plugs. When using standard plugs, they are near the top of the list for me too.