Brendan :
You didn't mention headers, which IMO are the first step (biggest bang for
the buck) to take. Then I'd go for cam (push rods & springs) & compression
. Also make sure your rockers are up to snuff. The factory arrangement is
adequate, but does wear out over time.
I can't give you any numbers, but headers, cam and compression will give
you a very noticeable "seat of the pants" increase for a relatively modest
price. Don't get too carried away, or you'll start breaking other things
(differential, transmission, etc.).
Most people say polishing is of dubious benefit (may actually hurt overall
power), and the ports are plenty big enough for street use (the TR4
actually has smaller intake passages than the TR3, to help midrange power).
There are some mods that can be done (by you) to the compression chamber
and liner to improve breathing, but you'll need a special head gasket to go
with them.
Of course, there's a _whole lot_ more you can do (Moldex crank, Mallory
dizzy, Webers, bigger bore, etc.etc.) but IMO it falls into the
'diminishing returns' category. As Ken likes to say, "Speed costs money.
How fast do you want to go ?".
Shameless plug :
Send $15 to
Dick Ames
TRSC Regalia sales
27301 Via Rioja
Mission Viejo, CA 92691
949-830-0854
and request a copy of Tech Talk Vol 3 Performance Preparation. It's
written by several TRSC (Triumph Register of Southern California) members
who practice what they preach, including Ken Gillanders of British Frame
and Engine who builds some of the fastest racing engines around. Although
oriented to racing, most of the suggestions work well on the street too.
It has drawings for the cylinder mods and Ken sells the head gasket
cheaper than Moss (same gasket).
Ken will tell you that 87mm is only for 'pikers' like me <g> He sells 89mm
sets, and knows how to get up into the 90's. Ask him about his TR2 drag
racing trophies <g>
Randall
On Friday, April 30, 1999 8:01 PM, Brendan Shay [SMTP:shaydog69@hotmail.
com] wrote:
>
> I've got the urge to get a little more power out of my Fergeson 4-banger
in
> my TR4 and was wondering if anyone could tell me if they've tried
polishing
> the heads or ports, etc. Is there noticeable increase in power, and is
this
> something I can do myself? Also thinking of purchasing second cam that
> would be mild street setup - how much power increase should I see (I've
> already got the 87mm bore piston & liner set and engine is freshly
rebuilt)
> I figure why not take advantage for a little more 'pep'.... What do the
> wise LBC owners have to say about this?
>
> Brendan O'shea
> '64 TR4
>
>
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