[Beenaway2long]

I would think by now, you could tell if it was definately the trans slipping, by color, and smell of the fluid. Have you peeked in the pan yet?

The 6700 settling to 6400 is from the converter flashing. But thats also a "tell". Your 4500 stall converter is flashing 6700. So its WAY off, providing your trans fluid is still in good condition. Jester and Cobalt are spot on.

One thing that needs clarifying, is the gearing. The higher numberically, the easier it is on the converter, and will not slip/flash as high. Same goes with anything that makes it easier to get the car rolling. A 4.11 is much harder to get moving than a 4.88, so the 4.11 will flash higher, and slip more. Cobalts point is lower gearing (4.11) will allow the rpms to rise slower thru the rpm range, THATS PROVIDED you arent slipping. His converter choices are also excellent builders.

[painted jester]

If your tires break loose when you shift the tach. will climb momentarily! If your adrenalen is high you may not notice!

The converter on drag cars are limited in life!!! The abuse on power flashed on them bends the vanes inside the impeller!!! your converter may have reached its retirement age ! That's why you don't skimp on a converter for a drag car

I used to test trans. fluid by putting one drop of new fluid on a paper napkin and one drop of used fluid next to it,and if the old fluid drop spread out more then the new one it was time to change it!! This old trick from the 60s still works ( fluid brands and temperature must be the same)! I tried to make an example with a napkin and post it, but all my fluid is good LOL sorry!

" Don't do this " years ago: I used to run Vega 10" convertors behind an 800 horse 471 blown small block ( they were cheep and worked) But they only lasted for maybe a week end! I was on the street (Woodward) Cruising and pulled a hole shot showing off, and the converter disintegrated and the trans broke the bell housing of the main body and parts scattered all over the street The trans blanket and scatter shield is all that saved my leg's fluid got on my slicks I was going side ways into the other lane That scared me worse then Vietnam "Don't Do That" And I got a big Ticket!!
The only thing funny about this story is : My 38 Plymouth was towed 40 miles home by a little 'Model A' street rod!

To any one reading this! Don't skimp on a converter They are a bomb waiting to happen!
After that my converters were custom made!! no more Vegas or over the counter converters!!!! I had the life scared out of me!

You do run a scatter shield don't you!

Jester

[cobalt327]

Listen to the advice about the tranny cooler- that engine is going to heat the fluid even w/a tighter converter, so protect it from overheating the best you can.

[menoaz]

[cobalt327]

Originally Posted by menoaz

Was this the photo you were trying to post?

[painted jester]

If that's the picture what kind of crank case ventilation do you have?


Jester

[menoaz]

Just the air breathers.

[painted jester]

You need more crank case ventilation , especially with boosted engines!!! You need fresh air entering and boost pressure and contaminant's leaving the crank case. At the least a PCV and if your boost goes up you need more A header collector type evacuation or a pump type!!!! Boosted engines need it or your damaging internals, and losing horse power.


Jester

[painted jester]

I posted this on the wrong thread the other day LOL It was meant for this thread (better late then never)!! LOL

Here it isPositive-displacement or "Roots-type" superchargers tend to produce massive power at low rpm and taper off higher in the rpm range; from Idle to about 5500 Rpm on a low boost engine which is usually on the street or a weekend warrior!

You converter and cam don't come in till late and are wasting all your torque your putting out at your lower RPMs with a roots supercharger. Right off idle an engine with a Roots supercharger will typically have nearly full boost and massive power. This power increase will be fairly constant throughout the RPM range. Till it reaches an rpm point that the supercharger begins to lose efficiency!

Turbos are the other way around! low boost at idle and as rpm comes up boost increases to high rpm so you need high stall speeds and cam's that come in late!



Sorry its late LOL Jester

[menoaz]

Thank you for the reply, i got some 4.11 gears,I am changing converters Hughes give me a great price at 450 to fix mine. If I am losing torque imagin with all the torque my wheels are going to be coming off the ground really easy. If they all ready do abot 6" at part throttle.

[painted jester]

Originally Posted by menoaz

Thank you for the reply, i got some 4.11 gears,I am changing converters Hughes give me a great price at 450 to fix mine. If I am losing torque imagin with all the torque my wheels are going to be coming off the ground really easy. If they all ready do abot 6" at part throttle.

Post on the thread "What do your cars sound like?"

I think we would all like to see that! Its good when we can all help!!

Jester

[menoaz]

Heres an update on the hot rod... I finally got the car really close to what i wanted at the track. I ran a 11.12@125mph. With a 1.60 sixty foot. Now this is all i changed and i got the 6200 thru the traps that i wanted in 1/4 mile. I really wanted 10's with only 5lbs of boost. Got really close. Hughes worked on my converter to my specs with my old 9" for 450.00. Swapped my 4.88 to 4.30 ratio and got my Holleys boost referenced at Larrys Marine in Tucson for 150.00. Thxs everyone for all the info hope this helps someone else later.

[AutoGear]

AWESOME and thanks for posting that!

[PatM]

^^^Dittos^^^

[Mr. P-Body]

I'm a late arrival in this thread. I usually stay away from "blower" stuff... Too many opinions. Very few pros. It's obvious here, who's who on this site for blowers! My compliments and my thanks. I learn from Jester and Cobalt every time I read something they write. Everyone else, of course. I just had to point that pair out. Good stuff!

I have input. First an observation then a question. Your gear is still too "low" (higher numerical). BBCs with small blowers (what's your ratio?) make torque like big N/A Pontiacs. RIGHT NOW! Take advantage of the massive low-end and gear it "up". We use 3.90s for 461s in cars under 3,500 lbs. and 1/4 mile. That MIGHT be a little stretch, but 4.10s are certainly correct. With a little shorter tire, the "top-end charge" with 3.90s will significantly improve MPH, and usually a corresponding improvement in ET. The idea with a "torque" motor is to "short-shift 1-2 and maybe a little 2-3, but "let 'er eat" in 3rd. Which leads to my question...

Why are you limiting the RPM of a short-stroke BBC to 6,000? 427s are "safe" at 7,000 when you upgrade the rockers and distributor, with stock "everything else". With the small amount of boost you have, good forged pistons and good factory rods are "up to the task".

A nitrous cam is WRONG WRONG WRONG for a blower engine. Sorry, but it's true. You're pumping mixture out the headers... Too much overlap. Nitrous engines "like" it for the scavenging effect. They also generally have longer duration on the exhaust side than "blower" cams. IMO, with a Roots-style blower, you really should have a blower-specific camshaft. You can "adjust" the duration and lobe centers to suit your RPM requirements. We use Comp exclusively for this. They have good engineers. The valve train is the LAST place to "scrimp" when building a BBC. You need the good stuff.

FWIW

Jim