Denny McLain

[QUOTE=Mindgame]
My question isn't, "Are guys doing it with hydraulics?"... rather... those claiming to do this... what are your results?

We use to run flat tap hydraulics to 7500 rpm all the time. You modify the lifter so that it is basically a "solid" with very little plunger movement. I already know it can be done but IMO, without very low valvetrain mass it's a PITA.

When you consider that a solid can rev to 7500 rpm very reliably and still be low maintenance at that level, it just doesn't seem worth it IMO. But then, I don't want to question motives. Guys might start questioning the sanity of anyone who wants to build a 450+ ci small block or perhaps convert a set of race heads for the LT block.

Different strokes I guess huh. [QUOTE=Mindgame]


Mindgame

I’m running a hydraulic cam, LT4 intake, 23 degree heads making 472 rwhp SAE @ 6650 revving to 7200 and have the dyno sheets to prove it. So does Brent Bauer as I forwarded a copy to him.

In my experience I’ve certainly not found solid lifters to be either reliable or low maintenance as I’ve ruined three engines trying. Very happy with the street performance of 23 degree heads/hydraulics and the only issue is I need to change the 977 springs more often than I would like.

Got a set of 1 ¾ to 1 7/8 stepped headers with merge collectors that should arrive within the next couple of days and we’ll see how it does after tuning. Might be able to tweak out something in the 480 range. Dunno?!?

I’d love a 450+ ci small block and a set of convert race heads but watch what ya ask for. With the very dry cool weather we are getting now in Dallas and negative corrective factors, the car really is a bit of a handful to drive on street tires.

IllusionalTA

What 23 deg heads are you running?

aggiez28

i just sold my lt1 with 215RR heads.

very nice heads.

brook

SStrokerAce

TFS castings.

IllusionalTA

Bret that would be trick flow i'm assuming?

89385formula

Yes, TFS=Trick Flow Specialties

ddr698

Yes actually it was on the forum and then i sent it to ebay about a month ago. xxxsaintxx from this forum was the winning bidder a month ago on ebay but he couldn't put together the funds for payment. So the setup is back up for sale.

It is interesting having a setup like this on ebay. On one hand i get a lot of very valid questions. On the other i have people asking me, do i need to change my factory injectors and programming? Will i need a different exhaust or throttle body to get the hp potential you listed? Um im thinking maybe lol?

Course then i have the people from the corvette forum who act like i pulled these from a top fuel dragster. "Those are just WAY to big, 180cc heads are the way to go...." I honestly think AFR should produce smaller than factory heads and sell them. Sure they may be overkill, but when was the last time you honestly modded your car, put it together, and was happy with how much power it had a month later??? Not too many of us, so why go through 13 setups?

Dan

Denny McLain

They are Trick Flow all right, but also ported twice ending with 2.08 intake valves and 1.625 exhaust. As cast from the factory,the heads are not even close to a set of decent ported stock LT1's. The heads are a genuine 300+ cfm but it sure wasn't easy getting there.

SStrokerAce

Dan,

The story on these things is as good as the heads themselves.

I always wonder about guys that tout that 180cc heads are the way to go on everything. If they wanted ones that small that would work, they couldn't afford it.

Bret

Denny McLain

That's why I'm on this list and pay almost zero attention to the Vette forum.

Recently saw a rebuild of a C4 in which the guy went to a 383 stroker. His prior combination was stock heads with a ZZ9 cam. After spending much time with him telling him the newer grinds were much better and explaining why they were better he reorded another ZZ9 cam. Same for porting his heads while they were off while the block was being done.

Some people are hopeless.

SStrokerAce

Yeah not like you haven't been there done that huh?

Bret

LT4POWR

Denny McLain

Mine was the opposite...... being the space monkey with new stuff being shot off into outerspace not knowing if the rocket would land or not. That and buying stuff from less than reputible vendors like heads that had flow sheets showing 317/218 only to find they flowed 285/190!?!

Mindgame

LR,

You may have taken what I said a bit to the extreme. The point I was trying to make is that...

1) Higher ports typically have larger SSR's
2) Airflow velocity in a port is higher than 28" H2O testing
3) Higher port designs typically have more uniform cross section areas

If we can agree to accept just those 2 points (1&2) then we should also accept the fact that while 300 cfm from a low port is the same as 300 cfm from a high port, the advantage still goes to the high port.

Back to the AFR 215RR...

We put together a 355 last summer that made 491 or 492 rwhp (can't remember the exact number) with a set of the 215RR heads and a CFE intake. It also used a hydraulic cam and would pull well beyond 7000 rpm. This particular engine also had beehive springs, titanium retainers and hollow stem valves so it wasn't exactly sporting the cheapest valvetrain parts known to man.

How many NA 383 & 396 combos are making 500 rwhp again?

BTW, I build engines as a hobby. I'm no expert.

I can't argue that the AFR's may not be "worth it" to some of you but the potential is definitely there whether you like the idea of using them or not. Not exactly an inexpensive way to make the power that's for sure.

Denny,

Sorry to hear all the troubles you've had with solids & glad to hear you're happy with the hydraulic setup. One thing that always gets me about life in general, whether it be cars, boats, whatever... is the difference in experiences people have had with identical products.

Me personally.... I have not had a solid lifter failure in a street engine in over 10 years. Maybe I've been lucky but that's just my experience. One guy I know, had many a problem with trying to run a solid in a 468 BBC. Wasn't anything extremely radical but he lost a lifter after 5k miles, then found a couple others before they went some time later. When the engine went in for a rebuild he had the shop check the lifter bore relations and they were "bad". He had the machine shop index and bush the lifter bores and never had another problem with solid lifter failures.

Now, every time I hear of someone having a problem I immediately begin to wonder.... how good are the lifter bores.

I also wonder about....

type of lifter used
how good the oiling is to the lifters
etc...

Not to say that lifter bore indexing would have eliminated your problem just another experience I had the chance to observe and share.

As for big small blocks... I have a 457 in the car now and it's a blast!

This engine made 777 hp and 651 lbs-ft. It turns 7300 to do that but it seems extremely comfortable at that rpm. Slightly less tempermental than the 383 it replaced.

It has a few crazy pieces on it like the Petersen SS oil pump but most of the stuff is recycled race parts I've accumulated over the years. Old parts never die, they just end up being overkill on another motor.

Oh BTW Denny,
How did you arrive at your collector length?

I have a very interesting story about a length guestimate that cost me right at 15 lbs-ft just about everywhere! Luckily we had some time to try other combinations before settling on a length.

-Mindgame

Denny McLain

I’m happy because I driving instead of calling a tow truck/walking home. The late fall weather really helps make power through no fault of my own and the price is right.

You’re either lucky or I’m unlucky or a bit of both. Honestly don’t know why I had so much trouble but I tried both Crane and Comp lifters. For sure I had the most problems with the Crane lifters and the lifter bores were never checked.

Don’t know about oiling either really but I tried restrictors, no restrictors, stock pump, Morroso blueprinted pump. You name it……… same end to the story. Tight lash, loose lash, just right lash via the cam card, etc. Dunno??

Add hydraulic lifters, some oil and so far no problems except premature spring failure which must be due to either bad/wrong springs or simply .630 lift on the street.

How did I arrive at the collector length? It was what they sold. Honestly didn’t even think to ask and you’ve got me embarrassed that I didn’t.

Was planning on playing with the car on the dyno with different length extensions and open headers vs closed headers. Done this twice before with different combinations and the car dynoed the same with open headers, 18 inch extensions and through a very good dual 3” exhaust with the biggest DynoMax mufflers that would fit. Kinda of expecting it to do better through open headers, but we’ll see.

Damn expensive hobby is all I’ll say. My wife would castrate me if she knew what I’ve spent over the last 20 years on cars.