Mr. Lang,
For gods sake don't pay two thousands dollars for Carillo rods! Carillo
makes a great product!...but I make my con-rods from billet titanium!
>From your posts...I assume that you race your car...we have talked about
this before...find out if you can, "within the rules", use custom
machined connecting rods. I will gladly make you a set...at no charge.
Desk top Dyno is fun to play with...but as you surmised the data may not
be entirely accurate.
This actually opens up a whole discussion. What is power...technically
how is it measured?
How can you make a simple Dyno for your engine? Cost $300.00 or less.
Best regards,
Jim Swarthout
-----Original Message-----
Hi,
I have a dumb question. I would like to converse with folks that have
run Desktop Dyno to compute theoretical power curves for TR6 and have
then gone to a dyno to see if the numbers are right.
According to the numbers I'm putting in, my current engine should have
peak HP in the 195 HP range and nice fat torque from 2000 to 6000 (169
ft-lbs at 2000 to 168 ft-lbs at 6000 with the peak or 209 ft-lbs at
4000). This seems a bit more than I thought I should be getting, so I'd
like to swap stories with anyone that's actually tried to correlate the
numbers with reality.
I know I'll get at least one "so Bob, whacha running?" query so here it
is in a nutshell:
TR6 motor, .040 overbore, forged dome pistons, head milled to 10:1
yielding about 11:1 total compression ratio, mild port-match, early TR6
head (narrow port), Weber DCOE 40's (28mm "chokes"), Piper BP270 cam
(264 duration, .410 lift at the valve), balanced (recipro on the
spinning parts, rods balanced end-to-end), stock valves with a
three-angle valve job and stock rockers with "treated" Piper single coil
springs (about 90 lb/in**2 seat pressure), tubular pushrods.
I run leaded race fuel because the head never got the hardened valve
seats, static compression is about 240 lbs/in**2 with the engine hot.
For some reason, nearly 200 HP sounds like it's a bit optimistic. I
should think that 160 - 165 was more like it, but maybe I was too
conservative with my estimates. I can tell you that the first time you
tromp on this baby, it scares the heck out of you! But I thought that
was the gears and the slicks, not ultimate HP. If it is HP, then I
actually should be a bit quicker (owing to the curb weight of 2000 lbs
(mandated by rules).
The reason I'm asking all this stuff is that "Charlie", my machinist has
a pile of new stuff from me and this setup should yield 210 HP peak (at
6500) and torque peak up quite a bit (160+ torque from 3000 to 6500).
Strangely, this might be a bit too radical for my uses - but I coould
probably "do" another cam before Charlie gets to my job... maybe I
should break down and buy a set of Carillo rods! The $2k price tag is
hard to take, though. Really hard to take!
Yeee - ha!
rml
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