Did a retro, 84 corvette, from twin TB,s to Edelbrock performer. New engine handbuilt by Napa machine shop, rated at 300hp, 4 bolt main, 2.02 exhaust valves, 212 cam, [ mild].
Should it go faster than this, pegged at 135 3400 rpm, was not cutting out, did not lack fuel; Running electric fuel pump 30 gallons per hour!
What should i do next, should it run about 160 or so with this set up?
Went with a 750 cfm, it dident make any adjustments, running 600 cfm again, it run great with that set up.

Should go faster than that my friend

Stupid new engines not going fast enough.

Did a retro, 84 corvette, from twin TB,s to Edelbrock performer. New engine handbuilt by Napa machine shop, rated at 300hp, 4 bolt main, 2.02 exhaust valves, 212 cam, [ mild].
Should it go faster than this, pegged at 135 3400 rpm, was not cutting out, did not lack fuel; Running electric fuel pump 30 gallons per hour!
What should i do next, should it run about 160 or so with this set up?
Went with a 750 cfm, it dident make any adjustments, running 600 cfm again, it run great with that set up.

Napa sold you one of Michael Waltrip's non-winning DEI motors that was hand built by Theresa Earnhardt.:rofl: :rofl: :rofl: :rofl:

It should definitely be faster than that.

Napa sold you one of Michael Waltrip's non-winning DEI motors that was hand built by Theresa Earnhardt.:rofl: :rofl: :rofl: :rofl:

It should definitely be faster than that.
:goodpost: :rofl: That made me spit coffee on my computer screen!:rofl: :goodpost:

The peak should come at a higherrpm than 3400. Maybe to high of a gear to pull ? Are you using stock rear-end and tranny ? I have a very modified ----84----that turns 8000 rpm. It is however not streetable.

So she should run faster than 135 then right, full open throttle, runs around 3200 to maybe 3500, cant quite remember, she'll run 5500 in a lower gear.
So whats it going to take to make this baby run 160 mph, with a 300 hp engine???:beerbang:

My original set up 383 ran 148mph, so now i'm down to 135 pegged with the supposed 300hp.
205 ran 140!
She will scream to a 100mph, but up to 135 she's done,
I havent wrapper her up in 4th yet, at 5500, only overdrive, but she does not run out of petrol, she can run all day at 4500 rpm, so no balls at 135mpg WTF???
What do you think???

So she should run faster than 135 then right, full open throttle, runs around 3200 to maybe 3500, cant quite remember, she'll run 5500 in a lower gear.
So whats it going to take to make this baby run 160 mph, with a 300 hp engine???:beerbang:

My original set up 383 ran 148mph, so now i'm down to 135 pegged with the supposed 300hp.
205 ran 140!
She will scream to a 100mph, but up to 135 she's done,
I havent wrapper her up in 4th yet, at 5500, only overdrive, but she does not run out of petrol, she can run all day at 4500 rpm, so no balls at 135mpg WTF???
What do you think???

If it will turn 5500 rpm in a lower gear my first thought is it has to high a gear to pull. What diameter is rear tires. Is 4 th gear 1 : 1 ? I can't think of another reason it would pull well in one gear and lay down in another.

I would think that it should go alot faster than that!

If it will turn 5500 rpm in a lower gear my first thought is it has to high a gear to pull. What diameter is rear tires. Is 4 th gear 1 : 1 ? I can't think of another reason it would pull well in one gear and lay down in another.

I'm running the 4+3 trannsmision, cant remember what the overdrive ratio is, i'll have to run her again without overdrive, but i dont like geting past 4500 rpm, malke's me nervous, it was a lot o work putting in this 4 bolt main.:cheers:

Sounds like a gearing problem to me. That car outta run alot faster than that...:burnout:

If you can fit it under your hood, try an open carb. spacer. If you can't, try cutting down the dual plain divider . I once built a v6 chevy w/ tbi that had a crossram type manifold, both banks were completly seperate of air & gas, it hit a brick wall at 4000 rpm, I just cut out the center of the tbi adapter and gained more top end.

Did you install the engine?
Maybe somebody installed a govener?

Good possibilty, someone might have put the screwing to You when they installed the motor.:vomitbuddy:

I'm running the 4+3 trannsmision, cant remember what the overdrive ratio is, i'll have to run her again without overdrive, but i dont like geting past 4500 rpm, malke's me nervous, it was a lot o work putting in this 4 bolt main.:cheers:

That could be your trouble. Overdrive ratio might be just to high to pull with the H P you have. I have a 540 BB. At 8000rpm it will do App 160mph. It has 4.11 rear axle. It should be faster----I think----it has a powerglide tranny and shifts to quickly off the line. Everything has a bearing on speed. HP , tire size, rpm tranny gears. It all has to work together.

Good possibilty, someone might have put the screwing to You when they installed the motor.:vomitbuddy:

Or the actual hp rating, i really need to get it dynoed to see where it's at!

You said you had a performer intake, not performer rpm, those are only good through 5500rpm. The do have a divider all the way up to the carb. Make sure your throttle is opening 100%. You may have the wrong cam or cam timing. Gearing on these cars should get you to 150 mph plus, unless you have a 2.56 rear gear. As your speed increases , the hp required to go faster, goes up faster then you might think.

Yes, with that build it should scortch past that mark.:thumbsup:

Did a retro, 84 corvette, from twin TB,s to Edelbrock performer. New engine handbuilt by Napa machine shop, rated at 300hp, 4 bolt main, 2.02 exhaust valves, 212 cam, [ mild].
Should it go faster than this, pegged at 135 3400 rpm, was not cutting out, did not lack fuel; Running electric fuel pump 30 gallons per hour!
What should i do next, should it run about 160 or so with this set up?
Went with a 750 cfm, it dident make any adjustments, running 600 cfm again, it run great with that set up.
are you in overdrive? shift down to high gear . 150 mph in not in the capabilty of 300 hp

So whats it going to take to make this baby run 160 mph, with a 300 hp engine???
What do you think???
About 280 hp. Put another way, you're not making 300 hp. Not even close. A stock 300 horse LT1 will go 165 or better. Sounds like you have the basic "260hp" crate GM engine, combined with porr gearing or gear selection to bog it in the low 3000 RPM area...=135 mph.

shift down to high gear . 150 mph in not in the capabilty of 300 hp

HUH??? Try again, using English this time please...

My basically stock '77 vette with the pathetic 185 HP L-48 would do 135 MPH. I think his problem is with that 4+3 Doug Nash tranny

Ok mates, here's what i got one more time;

It's a said 300 hp Machine shop built engine, using spec charts, so no, it was not sold as a graphed/dynoed engine, this is chart built only.
4bolt main, 2.02 exhaust valves, 212 duration cam, i want to beef the cam.
WHAT CAM SHOULD I GET FOR STREET??????
Ignition is Exell HEI, Fuel pump 30 gallons per hour, Edelbrock performer manifold and 600 cfm carb, tried 750, bogged down, went back to 600 runs like a banshe.
Screams to 100 mph can pull 5000 rpm, [ ouch] kick in overdrive and she runs 135 mph, [rpm approx 34-3800] cant remember but it wasent high, [throttle is opening 100%] then she sits there, thats all she got, 205 hp original setup ran 140 mph, 383 ran 148mph.
MY FIRM BELEIF IS THAT IT IS RUNNING OUT OF hp AT THAT SPEED!
Should i beef the cam and roller rockers???? i have a 212 intake duration, what will the idle be like at 278/288????
WTF??:burnout

HUH??? Try again, using English this time please...

At least you got a please, must be nice.

:thumbsup:

I'm in overdrive at 3500 rpm, 85 vette runs 150mph at 245, so how does 300hp not work for 135mph??
GTP grand prix runs 138mph with 260 hp!:beerbang:

Damn rights my 85 when 150 mph but now with the 3.54 gears probably only 140 mph

135 is just getting warmed up!

135 is just getting warmed up!

Any suggestions on a cam??:thumbsup:
What rpms are you running in overdrive at 130 mph??

Is your speedometer acurate? Verify by another car. To get an idea what rear axle ratio you have, run your car to 70 mph in direct drive ( 3rd in 700r4, 4th with out o.d. in 4+3 )if your speedo is acurate, the tach will show you your ratio. 3000=3.07, 2800=2.79, 2600=2.59.
Make sure your timing advances when you rev it. Try advancing the ign. timing. About your cam, maybe talk to a cam maker or edelbrock.
Another thing you can do is hook up an acurate vacuum gauge to manifold vacuum, see what the gauge reads when your at that 135 mph load. If you still have 1 or 2 inches under that load, you have an air flow issue. It should read zero, maybe your secondaries arent opening, I can't remember how to adjust the secondaries on those carbs. A carb. spacer might help you alot. What kind of air cleaner set up you running? Not alot of room to run a 14x3 filter.

You know I don't worry about those speeds over 100, I am rarely ever there. Now the speeds under 100 that is where races are won and lost!:burnout:

I went back to the engine builder for camshaft specs. It turns out that the cam is built for low end torque, which is why she screams off the line and bolts to a 100 mph, but starts to loose interest past 125 mph.
Intake duration 204
Exhaust duration 214

If i go with a longer duration camshaft, i could gain more top end, but low end torque would be lower.
It has a flat tappet cam in it, rated at 300 hp, possibly flat top pistons, for sure 4 bolt main.
After an 1800 mile round trip this last weekend, it's almost impossible to get past a 100mph anyway, too risky and dangerous.
What do you think mates, is it still a bad *** if it peggs at 135mph ??:burnout:

Here are some sample numbers. They are not pertinent to the Corvette necessarily, but they are typical.

In general, 60 MPH requires about 15 HP. Table 1 shows the power rise that must accompany an increase in speed.

Speed (MPH) Change (%) Horsepower Change
60.00 -- 15 --
75.60 mph 25.99% 30 hp
95.24 mph 25.99% 60 hp
120.00 mph 25.99% 120 hp
151.19 mph 25.99% 240 hp
190.49 mph 25.99% 480 hp

It has a flat tappet cam in it, rated at 300 hp, possibly flat top pistons, for sure 4 bolt main.
After an 1800 mile round trip this last weekend, it's almost impossible to get past a 100mph anyway, too risky and dangerous.
What do you think mates, is it still a bad *** if it peggs at 135mph ??:burnout:
No WAY your engine is making 300 hp. More like 160hp.

And no, it's not "bad assed". A bone, box-stock 205 hp '84 could go 145 or better.

No WAY your engine is making 300 hp. More like 160hp.

And no, it's not "bad assed". A bone, box-stock 205 hp '84 could go 145 or better.

So what will a bone stock 93 with manual do?

My nearly stock '85 will tear 135mph a new one. Hope You get it figured out.:thumbsup:

The cam you mentioned: 204/214 sounds like an Edelbrock Performer cam. Do you know what your compression is? It should be at least 9.5:1.

The performer cam is very mild and will be all done by about 5000 -5500 RPM.

So what will a bone stock 93 with manual do?

Should do about 165 in 5th gear.

Should do about 165 in 5th gear.

Good god. Maybe I'll wait to teach my wife to drive a stick

Good god. Maybe I'll wait to teach my wife to drive a stick

:coffeetime: I'd skip that part period.

Here are some sample numbers. They are not pertinent to the Corvette necessarily, but they are typical.

In general, 60 MPH requires about 15 HP. Table 1 shows the power rise that must accompany an increase in speed.

Speed (MPH) Change (%) Horsepower Change
60.00 -- 15 --
75.60 mph 25.99% 30 hp
95.24 mph 25.99% 60 hp
120.00 mph 25.99% 120 hp
151.19 mph 25.99% 240 hp
190.49 mph 25.99% 480 hp

Thanks theo, thats very imformative info there you dug up.
I have just changed my air intake to another style, straight bolt on performer side breather, she's a lot peppier, i'll let you know where she pegs when i see the right time.:burnout:

No WAY your engine is making 300 hp. More like 160hp.

And no, it's not "bad assed". A bone, box-stock 205 hp '84 could go 145 or better.

Tom, i have to agree, i need to have it dynoe'd, seems a shade limp at 125mph for 300 horses, this old girl outta scraem to 150mph, not running out of rpm's..:cheers:

The cam you mentioned: 204/214 sounds like an Edelbrock Performer cam. Do you know what your compression is? It should be at least 9.5:1.

The performer cam is very mild and will be all done by about 5000 -5500 RPM.

Yes, i beleive it's that model, i suppose according to specs that the mild cam rating is very quick off the line, and she fly's off the line, but runs out at about 4800 rpm, so power band is limited unless i step up to the next size,or two!

Ya'll are crazy!

Had mine to 125 this weekend! Haven't done that in a long time! Needed to be reminded of the power of these cars! lol

Compression Ratio might be a little low with that engine to make maximum HP. Check with your builder and see if it's below 9:1 compression. If so, the only way to increase the HP with your combo is to get the compression to at least 9.5:1 to take advantage of that cam.

Find out if the heads are 64cc or 70+cc. You may have an open chamber head design which will reduce your compression ratio quite a bit. A set of Vortec heads with a compatible intake will wake it right up as well or possibly a set of L98 heads with smaller combustion chambers.

Had mine to 125 this weekend! Haven't done that in a long time! Needed to be reminded of the power of these cars! lol

I hit 120 this weekend but realized just how touchy steering is and the road wasa little rough so I backed out. Super fun though. The friend riding with me screamed like a little girl to slow down. I'm still laughing about it.

Simple bolt ons to try-
1.6 rockers
retarding cam timing
edle. rpm intake
carb. spacer
If you want to get your compression up with those heads, 1st measure piston/valve clearence.
If you got clearence, deck the heads & install thin head gaskets. Felpro 1094 are 0.015 thick compared to most are 0.045 to 0.055 thick. Maybe half a point comp. increase.
IMO iron VORTECs are better than alum. L-98 heads on any day. They have great flow at lower vavle lifts & more modern chambers.

Simple bolt ons to try-
1.6 rockers
retarding cam timing
edle. rpm intake
carb. spacer
If you want to get your compression up with those heads, 1st measure piston/valve clearence.
If you got clearence, deck the heads & install thin head gaskets. Felpro 1094 are 0.015 thick compared to most are 0.045 to 0.055 thick. Maybe half a point comp. increase.
IMO iron VORTECs are better than alum. L-98 heads on any day. They have great flow at lower vavle lifts & more modern chambers.
Vortecs definitely have an advantage over the L98 but he may not want to change the manifold out along with the heads. But for the price of admission the Vortec route is a much better route. Unless the CR is 8.5:1...

Vortecs definitely have an advantage over the L98 but he may not want to change the manifold out along with the heads. But for the price of admission the Vortec route is a much better route. Unless the CR is 8.5:1...

Whats the deal with vortec heads anyway? Some say you have to use certain casting numbers and all that. So if I were to buy some vortec heads for my vette(I already have a vortec intake manifold for my tpi, which heads will work best with a superram on a 350?

I hit 120 this weekend but realized just how touchy steering is and the road wasa little rough so I backed out. Super fun though. The friend riding with me screamed like a little girl to slow down. I'm still laughing about it.

Dude that is awsome!!:thumbsup:

Thanks fellows, let keep em running!
I smoked my buddy off the line in his 91 LT1, i enjoy that view in the rear view mirror, we are going to try a 1/4 soon when applicable.
They are always grinning at the line, but it's that look at the next light, WTF???
That ole girl dont run to bad for an 84 with edelbrock performer, cam, intake and carb::burnout:

She made 140mph today:beerbang:

She made 140mph today:beerbang:

The little train that could!:sm_party:

You have more guts than I do! lol :sm_party:

i dont like geting past 4500 rpm, malke's me nervous, it was a lot o work putting in this 4 bolt main.:cheers:

Why is that? The stock engine will easily spin close to 5500 rpm.

I still haven't gotten mine close to there yet!

I still haven't gotten mine close to there yet!

What the He!! are you waiting for:smilielol5: Just kiddin. I hit 100 almost every day just cause I can:sm_party:

Sure lets you know that you are alive!:sm_party: :sm_party:

QUOTE=jrzvette;338011]Why is that? The stock engine will easily spin close to 5500 rpm.[/QUOTE]

5500 rpm, would that be safe for a 4 bolt main/ forged pistons, for more than a few seconds, well serviced with synthetic oil?? Makes me nervous, you ever put an engine in an 84, uhhh!
Makes for a few sundays! LOL!!:givemebeer.sml:

140mph BOYS IS HAULING a$$! lol.

Napa sold you one of Michael Waltrip's non-winning DEI motors that was hand built by Theresa Earnhardt.:rofl: :rofl: :rofl: :rofl:

It should definitely be faster than that.

:iagree: Should run faster :beerbang: :seeya:

What the He!! are you waiting for:smilielol5: Just kiddin. I hit 100 almost every day just cause I can:sm_party:

:smilielol5: :smilielol5: