Feels like I am hitting the Rev Limiter to early?

[MeanGreen]

I have an 89 GT with Edelbrock Intake/Heads E303 Cam, 70 mm Throttle body, 1.7 RR's, shorty headers, exhaust, 3:55 Gears.....

As soon as I get to like 5100 RPM's the car gets all sorts of F'd up like I am hitting the Rev Limiter already and just falls on its face. What could be causing this? Fuel Pressure? Timing? Need some help diagnosing this fellas

 

[TheBocSez]

I would lean towards Fuel Pressure or Valve Float. I had a similar issue and It was the valve springs. Replaced them with new stronger ones and no more problem.

 

[MeanGreen]

I would lean towards Fuel Pressure or Valve Float. I had a similar issue and It was the valve springs. Replaced them with new stronger ones and no more problem.

I could see maybe Valve Float if I was running a Huge Cam but not with an E303? I mean the Heads are new and came with upgraded spirngs.....

 

[ronburgundy]

it still could be float. your lift is at .529, which is getting respectable.

 

[86bluecobra]

I could see maybe Valve Float if I was running a Huge Cam but not with an E303? I mean the Heads are new and came with upgraded spirngs.....

Now I maybe wrong but I thought valve float had more to do with rpm then lift. If your valve springs are weak then they are not getting closed by the time it takes for the valve to open again. I can see how lift would effect it a little but it would mostly be an issue involving weak springs.

 

[StarFox07]

it still could be float. your lift is at .529, which is getting respectable.

Maybe i'm not considering something, but I thought the e303 was .498 lift?

 

[86bluecobra]

Maybe i'm not considering something, but I thought the e303 was .498 lift?

he has 1.7 Roller Rockers not 1.6's.

 

[StarFox07]

he has 1.7 Roller Rockers not 1.6's.

Ah ok, i still have many things to learn.

 

[86bluecobra]

Ah ok, i still have many things to learn.

You and me both Brother.

 

[superhuaman]

i have the same setup (1.7 with ecam) but its on ford svo gt40 alum heads, and i dont seem to have the rev problem (at least in neutral lol).

 

[Black1987Stang]

yeah 1.7's add supposedly .030 of lift....


Getting to the rev limiter problem, Do you have a MSD box?? My friend has a 6Al box with a 6,000 pill in it and was breaking up, sputtering, misfiring around 4,000+ rpms......We had just put in the 6al (used) so we figured it was that, I said to pull out the pill for the hell of it and once he took out the chip, everything cleared right up and ran like it should.....Just a thing to check.....Also how's your plug wires looking, I once had a bad miss, found out one wire had a split in it and was arcing to the side of the strut tower once a load got on the motor. Found it by looking at under the hood at night time, saw a mess of little blue sparks multiple times (Msd for you).

 

[mackey]

Had this problem once. Turned out the timing was way too low.

How low is yours set and do you have a spout connector in?


I bet when you hit the "rev limiter" it sounds like it is just taking in air.

 

[MeanGreen]

I dont have a timing light and havent had any time to take it to the shop to check the timing so that may very well be it

Also Blackstang I still have the stock ignition. I had MSD in my last 5.0 and it was complete poo and did the same thing you described.

I'll start messing with the timing this weekend as well as the Fuel Pressure and see if that clears it up. Might just be the Springs in which case anybody know what paticular brand would be good for Edelbrock Performer heads besides the ones that already come with? Maybe Anderson?

 

[mustangkid05]

^ 1

 

[JChalfan]

I dont have a timing light and havent had any time to take it to the shop to check the timing so that may very well be it

Also Blackstang I still have the stock ignition. I had MSD in my last 5.0 and it was complete poo and did the same thing you described.

I'll start messing with the timing this weekend as well as the Fuel Pressure and see if that clears it up. Might just be the Springs in which case anybody know what paticular brand would be good for Edelbrock Performer heads besides the ones that already come with? Maybe Anderson?

I would look other places before I started swapping valve springs. Like you said, timing would be a good place, and then start looking at ignition components.

I ran a E303 with 1.7RR's on stock '94 Cobra GT40 cast iron heads with stock springs and about 30,000 miles, and had no issues pulling to 6k or so (on the stock tach I'll admit).

I just doubt the springs are your problem, rule out easier things first.

Jeff

 

[Black1987Stang]

I agree I highly doubt it's the springs