Ol' Fart's Firebird Fantasy

[oldskool]

Originally Posted by Mark Yacavone

1 Yes, you can float the pins

2 Yes NHRA approved number

3 Don't argue about it, and don't use a lighter pin than you have to.

4. You can use a .980 pin or LARGER if rod is approved.

OK, so the optimum set-up would be to use a rod / piston / pin / ring combo which would just barely meet the NHRA min weight--is that correct ?

So, for this 350hp 400, that total weight would be 1458 g.

http://www.classracerinfo.com/Engine...px?ENGINE=2048

But I noticed some more specs on this page I need to ask about.

(1) The comp dist is listed as 1.695. But one of the approved pistons has a comp dist of 1.714. So, does that mean that you can use any comp distance you choose, which will optimize your combo with one of the approved length rods, and the max allowed stroke ?

http://www.summitracing.com/parts/sl...w/make/pontiac

(2) Wouldn't there be an advantage to running one of the BBC rods, because of the smaller big end and larger selection of cheaper pins ? The rod journals and bearings will be smaller, and lighter, with less bearing surface. All this will make the rotating assembly lighter, and should rev a bit quicker. Nothing major. But every little bit helps.

(3) That was for the optimum set-up. But it is also the most expensive. So, that brings up my final piston / rod question. Since the SP(TRW) pistons are MUCH cheaper than the other approved forged pistons, is it possible for a low buck guy to use the cheaper pistons and 6.625 Pontiac rods, and build a shortblock that can run slightly under ? Or to ask it another way, aprox how much quicker would the high dollar shortblock run than the low budget one I described ?

[Dwight Southerland]

1) Compression distance is minimum, not required.
2) Yes.
3) a) Yes. b) Reciprocating assembly optimization might be worth .12, including reduction of bearing size and weight.

[Billy Nees]

Originally Posted by oldskool

(3) That was for the optimum set-up. But it is also the most expensive. So, that brings up my final piston / rod question. Since the SP(TRW) pistons are MUCH cheaper than the other approved forged pistons, is it possible for a low buck guy to use the cheaper pistons and 6.625 Pontiac rods, and build a shortblock that can run slightly under ?

Yes


Or to ask it another way, aprox how much quicker would the high dollar shortblock run than the low budget one I described ?

With a "tow truck" motor? Maybe not as much quicker as you think.

Now can I make a suggestion? Seeing as you apparently have a ton of old parts and no body, either find a body that fits your parts or find a complete car. Especially if you are going to try a combo that no-one else has played with.
Put a basic short block together that won't self destruct and go to the track. A basic trans and converter and maybe not the perfect gear like you would in a Bracket car and see what it does. If it doesn't show you SOMETHING, maybe it's really not a good combo. Maybe you won't like driving a 4000-5000 LB car. If it doesn't work, get rid of the car or combo and, not a lot invested. And you can still be having fun and learning.

[oldskool]

Originally Posted by Billy Nees

Now can I make a suggestion?...Put a basic short block together that won't self destruct and go to the track. A basic trans and converter... and see what it does...Maybe you won't like driving a 4000-5000 LB car. If it doesn't work, get rid of the car or combo and, not a lot invested. And you can still be having fun and learning.

OK, thanks for the advice Mr. Billy. That gives me some ideas and also brings up some questions.

I've already got a 455 with 6x heads in a '68 Bird bracket car. Motor running but car not completed. It has a TH400 with 34 element sprag. No tricks--just basic bracket trans. Has a 9" converter--unknown stall.

My engine guy said the car might get into the high 10's. He's built quite a few Pontiac engines and has a 9 sec GTO now. But I think high 10's are a little optimistic. So, I'm figuring mid 11's.

Haven't weighed the car, but I figure just over 3000lb. So, right now I'm doing all calculations based on this 3000 lb car running 11.50.

(1) I've read that every 100lbs of extra weight will slow you down aprox a tenth. Is this what you have found to be the case ? Or ?

(2) Now, for the part about the 4000lb car. All the bracket cars I drove ran mid 12's. When I made a few passes in my 455 Ventura 2, it was a lot quicker. More G-forces and the shift points came quicker than I was expecting. 7.34 sec(1/8 mile) don't give an old dude much time to shift twice and check the other lane. So, a heavy car that would slow things down a bit would probably be a good idea at this point.

Now, I have a Safari wagon I bought for a future bracket car. Haven't started on it yet. It's not old enuff to run a Pontiac engine in Stock--mid 80's. But, since I already have it, and as you say, I may not like driving the heavy car, I just thought that it might be a good idea to go ahead and put the 455 into the wagon and just see what I can get out of it. If I can't get it to go quick enuff at the aprox weight it would need to be for a '76 wagon, then at least I'd have a Pontiac powered bracket battle wagon. It would be using the stuff I already have, to do the testing with.

So what do you think about that idea ?

(3) Another option I considered is running the 10.90 class with the Bird. I think they run that class at all the division races. If it runs as quick as my engine guy thinks it might, that is a possibility, which might take the least amount of time, work and $. But, it's a heads up class, and you must be able to run 10.90 on race day. I think there are also some safety rules that will be required when going quicker than 11.50.

Any thoughts about that deal ?

That's all my questions for right now. But I thought I'd mention that I was reading about the 10.90 class last night. They were talking about the latest electronic, computerized gizmos they have now that will automatically make the necessary tuning adjustments going down the track, that will produce almost exactly the same ET every pass. They mentioned one guy that dialed the exact same ET all season long, in his bracket car. It seems that if you don't have one of these systems, it is getting harder to win a big money race. They're afraid this could damage the sport and reduce the car count, and even cause some of the smaller tracks to close. But they say there is really no way to solve this problem given the level of tech for bracket cars, at most tracks.

Drag racing has come a long way from how it use to be. Now they got tranny brakes, delay boxes, and God only knows what else. This new technology has taken a lot of the fun out of it, and has made it even more expensive to compete. A little Test & Tune is about all most can afford nowadays.

By the way, the name of my wagon is "Woody". And the name of my '68 is "Early Bird". And here's a couple of more racin plates TJ did.

[Billy Nees]

Originally Posted by oldskool

OK, thanks for the advice Mr. Billy. That gives me some ideas and also brings up some questions.

I've already got a 455 with 6x heads in a '68 Bird bracket car. Motor running but car not completed. It has a TH400 with 34 element sprag. No tricks--just basic bracket trans. Has a 9" converter--unknown stall.

My engine guy said the car might get into the high 10's. He's built quite a few Pontiac engines and has a 9 sec GTO now. But I think high 10's are a little optimistic. So, I'm figuring mid 11's.

Haven't weighed the car, but I figure just over 3000lb. So, right now I'm doing all calculations based on this 3000 lb car running 11.50.

(1) I've read that every 100lbs of extra weight will slow you down aprox a tenth. Is this what you have found to be the case ? Or ?

(2) Now, for the part about the 4000lb car. All the bracket cars I drove ran mid 12's. When I made a few passes in my 455 Ventura 2, it was a lot quicker. More G-forces and the shift points came quicker than I was expecting. 7.34 sec(1/8 mile) don't give an old dude much time to shift twice and check the other lane. So, a heavy car that would slow things down a bit would probably be a good idea at this point.

Now, I have a Safari wagon I bought for a future bracket car. Haven't started on it yet. It's not old enuff to run a Pontiac engine in Stock--mid 80's. But, since I already have it, and as you say, I may not like driving the heavy car, I just thought that it might be a good idea to go ahead and put the 455 into the wagon and just see what I can get out of it. If I can't get it to go quick enuff at the aprox weight it would need to be for a '76 wagon, then at least I'd have a Pontiac powered bracket battle wagon. It would be using the stuff I already have, to do the testing with.

So what do you think about that idea ?

(3) Another option I considered is running the 10.90 class with the Bird. I think they run that class at all the division races. If it runs as quick as my engine guy thinks it might, that is a possibility, which might take the least amount of time, work and $. But, it's a heads up class, and you must be able to run 10.90 on race day. I think there are also some safety rules that will be required when going quicker than 11.50.

Any thoughts about that deal ?

That's all my questions for right now. But I thought I'd mention that I was reading about the 10.90 class last night. They were talking about the latest electronic, computerized gizmos they have now that will automatically make the necessary tuning adjustments going down the track, that will produce almost exactly the same ET every pass. They mentioned one guy that dialed the exact same ET all season long, in his bracket car. It seems that if you don't have one of these systems, it is getting harder to win a big money race. They're afraid this could damage the sport and reduce the car count, and even cause some of the smaller tracks to close. But they say there is really no way to solve this problem given the level of tech for bracket cars, at most tracks.

Drag racing has come a long way from how it use to be. Now they got tranny brakes, delay boxes, and God only knows what else. This new technology has taken a lot of the fun out of it, and has made it even more expensive to compete. A little Test & Tune is about all most can afford nowadays.

By the way, the name of my wagon is "Woody". And the name of my '68 is "Early Bird". And here's a couple of more racin plates TJ did.

#1 100 LBS is worth about a tenth down to about J-K-L. Lower than that, 100LBS is more than a tenth. Higher is less. Results may vary based on combo.

#2 Doesn't even deserve an answer. Too much speculating and assuming, and you know what assuming does, don't you?

#3 If you're going to go 10.90 racing or Bracket racing, that's fine. I won my first Division Championship 10.90 Racing and I've done very well for myself Bracket racing over he years BUT it's NOT Stock or SS racing. That takes a certain amount of dedication and commitment that a great deal of racers aren't willing to make.

#4? Most of us on here know all about what it takes to go 10.90 racing. If we cared to do that, then we would. This is a Stock and SS board.

Again, I will suggest, get a car that fits your parts or get a car. It is seeming to me that the cheapest, easiest way for you to wind up in something like a Stocker would be for you to put a 350 2V combo in your Ventura and sell your 455 stuff to finance it. My .02.

[oldskool]

Originally Posted by Billy Nees

It is seeming to me that the cheapest, easiest way for you to wind up in something like a Stocker would be for you to put a 350 2V combo in your Ventura and sell your 455 stuff to finance it. My .02.

Hadn't considered a 2 barrel. I've always run a Q-jet, except on a Hobby class dirt tracker. My Vent is a hatch so it will fall in between P and Q. You think a low comp 2-barrel 350 will run 13.70's ? That's hard for me to wrap my mind around. I had a high comp 350 Q-jet that only ran those times, in a lighter '68 Bird.

But I realize that with a high stall, max gear, light tranny with a 2.75 low, right cam, etc, etc, it will go a lot quicker. I reckin my main concern would be the 2-barrel. I can see how they might supply a 301. But I'm not sure they would supply a 13 sec 350. But I'm sure you've had a lot of experience with 'em. So what is the quickest time you've seen turned with a low comp 350P 2-barrel ?

I suppose what I need to do is learn all I can about a 2-barrel for racing. So, is this something that most anybody can do ? Or is it best to just come up with the $ and buy one from somebody who knows all the tricks. I reckin a better way to ask the question is, can I just do some simple jet and other minor changes, along with a good rebuild and tune, or will it require detailed internal mods done by a 2-barrel racing expert ?

Anyhow it's another option. And since this is a fact finding thread, I'll try to dig into it a little deeper. So, any of you guys reading this who have had success racing a GM 2-barrel similar to the one I'd have to use on a '74 Vent 350P engine, please post all the info you can share about it. I need info like what cubes did you run, what was the weight of your car, how many rpm did you turn, cam specs, stall speed, rear gear, ET, and anything else that might relate, in particular to running a 2-barrel as compared to running a Q-jet.

I'll ask a simple question which probably has a complicated answer. On very similar engines, with each combo maxed out, about how much quicker will the Q-jet car be, than a 2-barrel car? Hey, I know it's a dummy question. But if I knew the answer, I would not ask the question.

[oldskool]

So, if I tried to convert my Vent to a Stocker, I'd have a lot of changes to make. As you can see below, it has nice bars, but the dash has been replaced with sheet metal. And it has ladder bars, which would need replacing with Cal-Tracs or at the very least, homemade slappers.

Also would need a stock hood, front bumper, and I'm sure, lots of other stuff to make it pass tech. So, I might come out better trying to find a decent stock body, and start from scratch. That's the reasons I haven't considered it as a potential Stocker.

[oldskool]

I do like the idea of racing with leaf springs. They are just so much simpler to deal with. So that leaves a choice between a Bird or a Vent. I really prefer a Bird. But I like Vents OK too. And I figure a decent Vent body will be a bit cheaper than a decent Bird body.

So, if I don't use my '74, for the reasons mentioned, lets explore the other possibilities. The 350P was not used in a '71 Vent. It was used in '72, but is factored at 250hp. So that's no good. But in '73, it was used and is factored at 210hp. Also, the '73 model is the last year that NHRA allows 350P pistons, with valve reliefs, according to the info on the link below. The '74-'77 350 pistons are absolutely flat--no reliefs.

http://www.classracerinfo.com/Engine...px?ENGINE=2071

The old TRW forged piston # L2339F is legal for the '68-'73 350P. They quit making these a long while back. But you can occasionally run across an NOS set. I have 2 sets. One in the box and one in the 350P shortblock that came out of the 350HO Tempest I mentioned. The oil was milky in it, and I had no use for it at the time. So we never even tried to find out how the water was getting into the oil. It and the other 350 pistons are still over at my engine guy's place. There is also one high dollar piston that was approved over a year ago but is not on the list at the above link. It's a CP brand # P5-CP. This site shows that both it and the TRW 2339 are legal thru '74. So there is conflicting info there, between the 2 sites. But since the site linked below is an official NHRA site, I'll go by it. So, according to it, the '74 models can use any of the approved pistons for all years of the 350P, from '68 thru '77. This info can be found on the bottom of page 60 and the top of page 61 at the link below.

http://www.nhra.com/userfiles/file/N...edProducts.pdf

The 350HO shortblock I mentioned just has stock, cast rods in it. But in a 350, they should be good to at least 6200-6500rpm. I don't figure a 2-barrel 350 will pull any higher than that. I don't have any #46 heads to put on it. But I do have a good set of 6x heads I could use on it for testing purposes. I could find out if I can get a 2-barrel 350 to run under, without buying a set of cores and paying for the head work.

My engine guy has a 350 block with 8 sleeves in it, that he was going to use for a serious dirt track project. But all the tracks in our area shut down. So, I could use my NOS TRW pistons and his 350 block, and build up a strong 350 shortblock. Hey, I'm just sorta thinkin out loud. I reckin that's the way a lot of low buck guys do it--think of all the parts you have available and figure what you can put together.

I've got a 2-barrel on a '71 455, that came out of a Safari wagon. I wonder if that would pass tech on a '73-'74 350 Vent ? By the way, this same engine is legal in a '73-'74 Bird and lots of other models.

Any more comments on the possibility of running under with a '73-'74 350 2-barrel engine ?