93LS1RX7

iTrader: (8)

I have a Solid Roller 408 iron motor running 14 to 1 compression, a vacuum pump, Victor JR, Race Demon carb, AFR 225 heads ported by TEA (Flowed over 330 at .600).

CAM is a 268/275 .715 lift and I believe a 112ICL

Here is the issue.

The car made right at 500rwhp through a powerglide and a 5300 stall on the first full pull. First issue is that, EVERY pull the car has done, the HP curve is climbing fast until it hits 6200rpm where it goes dead flat and wont rev any higher. Never peaks and goes down just flat lines. When the car was EFI we (Mikey from Rapid) thought we were running out of intake. Thats why I went to the carb setup. She was on the Dyno this week and did exactly the same thing. Pulls up to 6200 rpm and will NOT go any higher.

No idea why? Maybe cam is wrong??

TSP Sent me a complete long block that they said they checked everything on assembly and they spec'd all the parts so it wasnt me picking mismatched parts.....

Second issue is almost more disturbing. The first pull the car made on a dyno jet it made right at 500rwhp at 6200rpm. Next pass it made 486, next pass 466 and so on. Mikey tried everything possible and by the last pull the car was only making 410rwhp with a solid 12.8ish AFR.

Mikey thought maybe the lash was off or the Cam sensor was bad. Well I checked the lash and it was off a little so I reset the lash to .023 cold and .018 hot (What TSP told me to do) and replaced the cam sensor.

I took it to the dyno this week and the car STILL wont make it past 6200 rpm with a nice 12.8 to 13.2 AFR.

It also only made 385rwhp on a mustang dyno which is probably right around the 410rwhp it made on the last pull on the dynojet, maybe a tad higher.

I am so frustrated. It has been over a year farting around with this motor and I feel like I am farther away from being done no than I was a year ago.

Anyone have any ideas?

speedracer5532

iTrader: (8)

I think .023 cold valve lash is way too much. I set my valve lash to .003 cold which gives about a .014 to 0.016 hot. Which lifters and rocker arms are you running? Who degreed the cam in? What valve springs are you running? Have you checked the degreeing of the cam?

JasonShort

iTrader: (242)

What valvesprings are you using?

93LS1RX7

iTrader: (8)

The valve springs are cranes doubles...dont know which models off the top of my head but they are rated to .750 lift supposedly. ThaSP said.

Rockers are 1.7 Jesels. Lifters are solid cranes I think.

TSP was supposed to degree the cam in. I havent checked it.

The lash seemed strange to me to but I triple checked with TSP and they said .023 cold .018 hot. Actually they started out saying .025 cold and .020 hot then reduced it to 23 and 18.

Maybe I will pull the heads, check the cam and call COMP to find out what it should be at.

NoMoreFWD

iTrader: (1)

The lash sounds about right. I just lashed a Comp Cams mech roller - .625 lift and the lash is .016/.018. Bigger cam, bigger lash.
TSP should have sent you the cam card, along with all other documentation pertaining to your motor.
I would be concerned about the numbers dropping on every pull. Sounds like something is hurt. Do a compression/leakdown test.
Not revving past 6200 rpm sounds like an electronic problem if I had to guess.

speedracer5532

iTrader: (8)

First off I don't think your valve springs are strong enough. I am not sure what the seat pressure and open pressure is on the crane dual valve springs. I am running Comp 917 dual valve springs with a seat pressure of 200 with an installed height of 1.800 inches and an open pressure of 596. I have talked with Mark Campbell at Crane several times and I know right now Crane doesn't make a good valve spring with an installed height of 1.800 inches for a big solid roller cam. I know they are working on a good valve spring and should be available in September.

I totally disagree with you on the valve lash. The cold lash should definitely be much lower than the hot lash. 0.018 lash sounds about right hot, but 0.023 cold will never get you 0.018 hot. I am running a Comp Cams solid roller cam (254/260 660/666 113+1) and on the cam card they recommend 0.014 - 0.016 valve lash hot. I set my cold lash to 0.003 and that gives me around 0.014 - 0.016 valve lash hot.

Agree with NoMoreFWD on doing a leak down and compression test to see what you get.

93LS1RX7

iTrader: (8)

Well here is what I found so far, just looking at the passenger side:

http://www.torquecentral.com/showthr...841#post335841

#2 and #4 intake valves are hitting the piston.

TSP told me they checked PtoV and also degreed the cam. They sent me a complete long block.

I will call them on Monday to discuss the issues and then I will find out which springs exactly are in the motor and I will also be degreeing the cam if not getting a new one.

I am VERY dissapointed that TSP failed this badly on something so basic considering it is a full race motor. Who knows what else is screwed up. When I find out the cam specs I will call Comp cams and double check the lash info.

GrannySShifting

iTrader: (10)

Clearence was possibly fine, but valve float changes everything

deputydog

Good luck, I'm doing a very similar motor just a little more compression and a more aggessive cam for nitrous. Once you fix you problem the intake is going to be your restriction. The victor jr runner volume is to small for a radical carb motor. Ill post pics of mine, we are cutting/welding a ford Victor 351-Y manifold to fit a LS6 head, trying for 650-700 N/A and then a plate and fogger.

JasonShort

iTrader: (242)

I have had alot of valvespring related issues with my solid roller motors in the past. Regarding solid roller motors, lifters and valvesprings are key. The other thing I have learned (the hard way) is not to use Crane products. I have had nothing but problems with their stuff. I suspect that your valvesprings are the problem. Just because they are rated at .750 lift does not mean that they can control the dynamics of the valve events at high rpms. I would look into a good Comp or Isky spring. The best place to start would be to talk with your cam grinder to see what they recommend (pressures).

Jason

93LS1RX7

iTrader: (8)

Texas Speed did the entire longblock. I trusted them to do it right and use the right parts.

I dont think the valves are floating but who knows.

I pulled the drivers side head an #3 and #7 were visably hitting.

SStrokerAce

iTrader: (2)

Well you found where all your power went.... down the tubes with the valves hitting the pistons. Those valves are probably junk now due to being bent.

As for your springs you need to know the exact installed height, installed pressure, spring rate and coil bind. I'd also go with a VERY good set of springs at that lift to make sure they will work.

Plus related to the cam... if all we get is the .050" numbers there is no way to know if the springs are enough for the lobes.

Bret

Asmodeus

sounds/looks like the springs were letting the valves float.

93LS1RX7

iTrader: (8)

May be valve float but the dyno graph didnt indicate it. I am going to see what TSP says tomorrow.

They are a solid company I hope they take care of the issues.

JasonShort

iTrader: (242)

That line in your first post is exactly the classic symptom of valve float.

No one is dissing TSP, but your engine is not the run-of-the-mill LS1. Solid rollers can be very tricky and the lifters/cam/spring matching is critical.

GrannySShifting

iTrader: (10)

valvefloat!

DAPSUPRSLO

iTrader: (14)

Yep, sounds like valve float as others pointed out. Mark C. indicated, as well as others, that when that does happen the springs can get super super hot and that would explain the drop in hp from consecutive dynoes. Get some different springs and other assocaited parts to set them up on that set up and see how it does. BTW, don't be afraid of tight springs. On my titanium valved street motor i've got 250ish/700ish springs with .754"/.760" and valve spring oilers. These parts were suggested by people in the know, but I have not run this setup so I can't speak 100% of the correctness of the parts.

slow trap

iTrader: (22)

i'll say it's valve float also. after the 1st time you float the valves power will keep going down. if you can i would get a pressure tester for the springs and check the ones that hit and see what they are,open and closed also.

smask04C5

iTrader: (1)

Suggest once the valvetrain, ptv, and everything else is thoroughly checked, add valvespring oilers. This single addition will drastically increase valvetrain life when running high lift and duration camshaft, such as yours.

93LS1RX7

iTrader: (8)

Well it seems like the consenses is valve float. While not the ideal thing, it does make me feel better that maybe TSP did check the PtoV clearance and just selected the wrong springs.

I am hoping that the valves didnt damage the seats or cause some other strange issue.

Valve spring oilers?