B2 Motorsports - Mat Twiehaus 427SBF Build - Page 2

Pman1961 · #21 (**permalink**) 07-30-2012, 07:58 PM

I love these type of threads. Look forward to the results and future builds!

951mat · #22 (**permalink**) 07-30-2012, 08:27 PM

Great catch Mark, I'll have to rethink that adapter. At least glad to know it can be done.

Olddog, lifters are solit flat tappets for street ability. Plus I can spin it a wee bit more gettin to that corner.

Mat

blykins · #23 (**permalink**) 07-31-2012, 01:55 AM

Quote:

Originally Posted by olddog

Thanks Brent & Mat. This is 10 times better than any magazine article. For one it will be honest.

Cam spec question:
*Comp Cams Solid Cam, 244/252 @ .050", 110/105, .600/.610"

I know Brent is not a fan of flat tappets, but solid rollers would not fit my picture of a reliable street engine. This a solid roller or solid flat tappet?

Not a fan, but after an hour or so of discussion, Mat and I came to that agreement. Road racing can bring out the revs sometimes and I just didn't feel comfortable with the engine stretching its legs on a hydraulic roller. Conversely, Mat didn't feel comfortable with the longer term maintenance of a solid roller, so we hit in the middle.

This particular cam is a nitrided core, plus I'm using newer EDM lifters. With the inner springs out, the seat pressure is 93 lbs and the open pressure is less than 300. So with the cam core, the lifters, the springs, and a case of Brad Penn break-in oil, I'll break this puppy in. I've already checked that the lifters spin in the bores and I can always get them to fire on the first crank on the dyno. I think we're in good shape.

FUNFER2, there is also an external pump wet sump system....

Clois Harlan · #24 (**permalink**) 07-31-2012, 08:10 AM

So Mat, when are you going to start posting some pics of your JBL build to ago with your engine build?

Just keeping you on your toes>

951mat · #25 (**permalink**) 07-31-2012, 11:44 AM

Now why would anyone want to see one of those? Just look at all the JBLs out there.

I suppose I'll start posting some pictures soon. It will be a new thread. Mostly top secret stuff going on right now in the build, so no pics. But coming soon.

Mat

jmarsey · #26 (**permalink**) 07-31-2012, 12:27 PM

Hey Mat,

There are a few of us :-))

John

Richard Hudgins · #27 (**permalink**) 07-31-2012, 01:56 PM

951mat · #28 (**permalink**) 07-31-2012, 02:11 PM

You're killin me Richard. Besides I'm more of a modest guy. That thing would just be bragging. I'll stick with my plain jane carburated 600hp, red/silver stripes/black numbers type of daytona coupe. Much more modest.

Mat

blykins · #29 (**permalink**) 07-31-2012, 04:17 PM

Valve seals came in...

It's not much, but it's progress. Rocker studs are in but loose...they generally need a little tweaking for perfect alignment.

Waiting on a rear main seal and then the fun stuff begins.

madmaxx · #30 (**permalink**) 07-31-2012, 05:21 PM

Brent,
Wtf is wrong with you? Is that a calculator? What are those numbers on the head? Real men know it right by feel and experience, fuk using tools and mathematics you pus!

blykins · #31 (**permalink**) 07-31-2012, 05:23 PM

Well...

Mechanical Engineer + OCD = numbers everywhere.

Those are install height measurements for each valve, plus spring shim thicknesses and where they go.

ERA Chas · #32 (**permalink**) 07-31-2012, 05:34 PM

At least they're not written in crayon! :-))
Spring rates for this cam Buddy?

blykins · #33 (**permalink**) 07-31-2012, 05:42 PM

Without the inners it's a whopping 93 lbs seat....hahaha

With inners, it's about 138-140 on the seat, about 370 open.

ERA Chas · #34 (**permalink**) 07-31-2012, 07:10 PM

Quote:

Originally Posted by blykins

Without the inners it's a whopping 93 lbs seat....hahaha

With inners, it's about 138-140 on the seat, about 370 open.

Thanks B.-surprisingly mild for a +.600 solid roller. Gonna dig out that bottle of EOS that Patrica sent ya?

olddog · #35 (**permalink**) 07-31-2012, 07:33 PM

Quote:

Originally Posted by blykins

Not a fan, but after an hour or so of discussion, Mat and I came to that agreement. Road racing can bring out the revs sometimes and I just didn't feel comfortable with the engine stretching its legs on a hydraulic roller. Conversely, Mat didn't feel comfortable with the longer term maintenance of a solid roller, so we hit in the middle.

Patrick just wet his pants

Quote:

Originally Posted by blykins

This particular cam is a nitrided core, plus I'm using newer EDM lifters. With the inner springs out, the seat pressure is 93 lbs and the open pressure is less than 300. So with the cam core, the lifters, the springs, and a case of Brad Penn break-in oil, I'll break this puppy in. I've already checked that the lifters spin in the bores and I can always get them to fire on the first crank on the dyno. I think we're in good shape.

From my industrial experiences I have always believed that if the surfaces have the right finish and the metal the correct hardness there should be nothing to break in or wear in a cam. Obviously the cam manufactures didn't see it that way, but the nitride hardened surface is a huge step my direction. I doubt you will have any issues.

blykins · #36 (**permalink**) 08-01-2012, 01:53 AM

Quote:

Originally Posted by ERA Chas

Thanks B.-surprisingly mild for a +.600 solid roller. Gonna dig out that bottle of EOS that Patrica sent ya?

I'm still on the look-out for some Schubeck ceramic lifters and if I find a new set, I'll swap. Smiths is out of stock on them for a few weeks. They are tool steel as well and will allow you to run the higher spring pressures. For a 6500-ish rpm engine though, this is sufficient, especially with the lighter valves, titanium retainers, etc, etc.

And yes, I'm surprised he hasn't commented in here yet...

Clois Harlan · #37 (**permalink**) 08-01-2012, 04:23 AM

Brent that is about the same springs that I am running on my aluminium heads. However, I think I am under carberated (750 QF). But, with my 202 heads I am only kicking out about 535 hp and 490 lbs tq at 6200 RPM.

Clois

ERA Chas · #38 (**permalink**) 08-01-2012, 06:30 AM

Quote:

Originally Posted by blykins

And yes, I'm surprised he hasn't commented in here yet...

Be careful what you ask for-he's in the sensory-deprivation tank at the Spa and can't be disturbed...

Clois Harlan · #39 (**permalink**) 08-01-2012, 10:06 AM

Is that one of those spa's they advertise in the uban newspapers where most of the business's are upstairs in the alley?

Sminor · #40 (**permalink**) 08-01-2012, 06:02 PM

Quote:

Originally Posted by Mstusc

I'm new here, but I want to buy something loud and expensive Brent has built. Very cool to share the build process, you are a great resource of info!

I don't know about expensive, but I bought something loud and brutally powerful from Brent, and I am glad I did. Brent, that little 428 was a blast on the straights at Mid-Ohio this summer.

Quote:

Originally Posted by 951mat

Thanks for starting this thread Brent. I cant wait to see assembly. You'll have the timing cover thursday.
Hey Mark, I talked to Dailey and Id bet there's no room for price negotiation. He does have a different modular system he's developing for Windsors. Might be a good application and slightly less $$$.
Kevin, I'm understand the question on the dry sump. I think it's great no one here questions the 550-600 hp.

just shows how twisted we are here on CC.
It may be a little overkill for me, but if I ever turn a hot shoe loose in it showing me how to drive it, I'll be glad I got it. And wait till u see it. It is actually art work.
Mat

Mat, bring your ride up to the London Cobra Show next year and do the track days at Mid-Ohio. Allen Grant was kind enough to drive one of the coupes a few laps and gave it's owner some pretty interesting tips.