Dyno Time
 

Tomorrow i am finally taking my engine to the dyno.
Its a 535 MR1 with 430 Highports BOP intake and a 1300 Prosystems carb.
14to1 compression running vp113 fuel.
Lets hear your guesses on what it will make.

Try 925HP.Tom

Good luck!

900ish

Lot of r&d on the heads and intake, cam? If so 1000.

905hp, 725 lbft tq.

Old cam 278 intake and 292 exhaust on a 114 cl it made 920hp

New cam
 

Pic of cam card.

Whew!!! That's a healthy cam! What ratio rockers are you using?

1.65

Hey John, 910HP ..

1020

Hey Charlie. I hope it's not less than before. Lol.

I'll revise my guess, given more info about the previous Dyno and cam specs, 975hp

955h / 820t

What's the difference between this build and previous one?

945 HP 790 TQ

Nice build!

983 hp :drive:

New cam, steel rods and heads.

Why that 113 on that cam?

I don’t think such will help your VE, but non the less I hope you reach your target power numbers.

Compression the same? Heads same except new?
If those are same and basically just the cam change I'll guess 940-950

New steel rods? Did you have Aluminum rods previously?

Hi Steve.... That 113 is the intake centerline

117 LSA on the cam. I'll say 1020 HP.

I thought it read .630 lobe-old eyes! I’ll still say about a grand!

I'm not going to post any numbers but it was down 50hp with this cam. I'm going to make a few passes with it and see then put the old cam back in.

I ran pretty much that same cam from lsm in mine, ran great. Sucks it didn't work out for you. Good luck this season.

That's disappointing..... Sorry to hear that.

That stinks bro, get a couple of runs to make sure the Dyno wasn't having a bad day

From my standpoint it is hard to say what is happening due to lack of specs.

535 ci

1) 920 HP (what RPM), 278 intake and 292 exhaust on a 114 cl (what LSA), what heads (flow and valve size), what CR

2) 870 HP (what RPM), 284 intake and 306 exhaust on a 113 cl (117 LSA), what heads (flow and valve size), what CR

Do run a power adder on this engine?

Stan

Not sure if he'll post much more info. But looking at the differences in the heads before and now would be a good starting point imo. He stated only changes were cam, rods and heads. Out of those 3 I'd pick heads as the issue. But not much info to go on here.

The new heads are supposed to be the 430 cnc port from Kauffman same as the old heads. Compression is at 14 to 1.

The new heads were bare and everything was transferred from the old heads to the new heads.

At what RPM does the engine my 920 peak HP?

Stan

7200 rpm

Your new cam is virtually the same as my Bullet nitrous cam. I'm running 1.75 rocker ratio. My LSA is 115 installed at 113.

I am going to do a leak down test today after work.

I was going to say what Slowbird did, the heads are the issue.

If your leak down test shows ok then why even go thru the work of putting the motor in the car to make a few passes if the new motor is not even the equal of the old one?

I guess your stuck with it for this race season, or do you still have the old heads?

That’s a bummer John! Where did the new heads peak this time? Same dyno as last engine? Can u share any of the dyno sheets maybe there’s something there that will help decipher what happened

I would also like to add to Stan's list of questions if you know how much vacuum was made at peak hp and the BSfC numbers from the dyno sheet?

Factoring no mechanical issues with the motor, Track time is a better indicator of power since he already has a reference point if the car is basically the same.

True!

Well the leak down test was anywhere from 4 to 13%. Nothing going on internally. I will try and do a compression test today.

If the only changes were cam, rods and heads, I'd say the combo needed tuned to those new changes? Intake specs to work with the heads, carb change to work with the new specs, cam wrong for head specs etc.?


What was the afr, bsfc, rpm range etc?


:confused:

I believe the heads were direct replacements for the original KRE heads that cracked.

I'd be looking to see if the porting program was changed to prevent the cracking issue. This problem was in a critical area of the port. Could easily knock down the power numbers considerably.

Thanks, I thought with the heads they were ported for more flow than previously. (why he changed the cam also)


:)

Good call by Paul. That would suck if thats the case. The High Ports gotta be paper thin at 430. Hate to say, but maybe move your program into the "Super Wedge head" territory. Your easily at that level.

JMO It is the new cam.

Stan

I talked to Jeff yesterday he said that the new port program shouldn't have hurt it. We all know how that goes.

I changed the cam hoping to pick up a little.