I couldn't pass a Sentra

[thirstybob]

OK, I'm a little surprised at how slow my '74 C20, 454/TH400 is. I really thought it ran good but I got spanked by a punk in a Nissan Sentra.
I shifted manually and barked the tires during up shift but I couldn't pass him.

I really need more. Does anyone know if 215 heads can me made to flow without breaking the bank. I like the idea of increased compression but I know the valves are small.

Any suggestions would be appreciated.

[Ziegelsteinfaust]

Your heads are not the biggest issue slowing you down, and while not the best even peanut port heads can lay down some serious numbers.

I would start with a cam shaft that feed the engine up to 5500rp., and a high rise dual plane. If you have a q-jet, and must have it. Use a 1" or taller open spacer to help with the manifold to promote cylinder filling. Also since a clyinder in theory can now see both sides of a carb. It reduces cfm size need for hp, and can help with mpg. Since the carb can be smaller, and flow more idealistic. Then add a air cleaner that does not have a drop base.

My friend built a pretty serious 454 with peanut port heads with the expectation upgraded heads would be bought soon. His 350 was dying, and he already had the 454. Along with a stash of parts to rebuild it. It was such a all around motor when we were still friends. He never got the upgraded ones he wanted. My guess it was a solid 400hp, and 500 lbft of torque. In his 66 C10 with 2.73 gears, and a posi. It could run 13.00-13.2 in the quarter.

https://www.hotrod.com/articles/ccrp...-engine-build/

[TrailerTrash]

Is your engine all stock? Let's hear the details

[thirstybob]

Originally Posted by TrailerTrash

Is your engine all stock? Let's hear the details

I have an Edelbrock 1407, Edelbrock Performer 2-0 and tru duals. I recently discovered that it has 215 heads from a 68-69 427 which I suspect is part of my problem. Other than that, stock and original.

I'm sure a more aggressive cam won't hurt but, I wonder if the heads can be re-worked or should I start looking for different heads?

[Dead Parrot]

Rear gear ratio and tire size?

Possible that he has made some stealth upgrades to that car so he can do exactly what he did and laugh about it to his buddies.

I would start with a basic tune up and verifying that your timing is correct and timing advances are working correctly.

[Getter-Done]

Originally Posted by thirstybob

OK, I'm a little surprised at how slow my '74 C20, 454/TH400 is. I really thought it ran good but I got spanked by a punk in a Nissan Sentra.
I shifted manually and barked the tires during up shift but I couldn't pass him.

I really need more. Does anyone know if 215 heads can me made to flow without breaking the bank. I like the idea of increased compression but I know the valves are small.

Any suggestions would be appreciated.

My first question would be.

Do you know the Punk in the Sentra and if it stock?

He may have had what we called (A Sleeper) back in the day.
















.

[blazer2007]

I got beat off the line by a Malibu taxi,I know your pain

[thirstybob]

Originally Posted by Dead Parrot

Rear gear ratio and tire size?

Possible that he has made some stealth upgrades to that car so he can do exactly what he did and laugh about it to his buddies.

I would start with a basic tune up and verifying that your timing is correct and timing advances are working correctly.

I agree DP, he could have had a sleeper. My timing and tune are dialed in as far as I know.
Do you think my 427 heads are holding me back?

[thirstybob]

Originally Posted by blazer2007

I got beat off the line by a Malibu taxi,I know your pain

Ouch

[Corts60]

Go ahead and find that kid again and have him hook a trailer up and you do the same. Then we'll see who wins.

[44th Miss Inf]

The 215 heads are closed chamber (app 100cc) are helping you, as the motor probably had 781s on it (117-119 cc from the ones I have cc’d) The most of these engines stock work out to 7.7-7.8:1 compression originally.

I class raced one of these engines (a later one with 236 casting heads aka peanut ports, and the factory flat intake and the heads and intake will support 546hp.

Before I swapped a thing on the engine, go thru the usual, fuel, timing, etc.

Timing chain good? I believe this was about the time GM used the plastic gears on the chains

Factory cam in these engines was lame

Parts store fuel pumps seem to barely provide enough fuel for a stock non performance engine.

How’s the trans? Rear gearing? Lots of variables

[thirstybob]

Originally Posted by Corts60

Go ahead and find that kid again and have him hook a trailer up and you do the same. Then we'll see who wins.

Tru-Dat!

[thirstybob]

Originally Posted by 44th Miss Inf

The 215 heads are closed chamber (app 100cc) are helping you, as the motor probably had 781s on it (117-119 cc from the ones I have cc’d) The most of these engines stock work out to 7.7-7.8:1 compression originally.

I class raced one of these engines (a later one with 236 casting heads aka peanut ports, and the factory flat intake and the heads and intake will support 546hp.

Before I swapped a thing on the engine, go thru the usual, fuel, timing, etc.

Timing chain good? I believe this was about the time GM used the plastic gears on the chains

Factory cam in these engines was lame

Parts store fuel pumps seem to barely provide enough fuel for a stock non performance engine.

How’s the trans? Rear gearing? Lots of variables

I'm planning a timing set swap.
Edelbrock mechanical fuelpump
Good TH400 with TransGo kit in it.
Not sure of my rear end gearing.

I've been tweaking and tuning for a few months, I think I have as much dialed in as I can.

Didn't the 215 heads offer higher a compression ratio? I thought I read somewhere that they were close to or above 9:1

[Sevens]

Originally Posted by thirstybob

I'm planning a timing set swap.
Edelbrock mechanical fuelpump
Good TH400 with TransGo kit in it.
Not sure of my rear end gearing.

...

Rear-end gear ration is an important part (if not the most important part) of this equation. If you have really high gears, your engine has to work harder (read less efficient) to overcome inertia.

You can have all the horsepower and torque in the world and not be able to get it to the ground if you have the wrong gears!

I would recommend figuring that out before worrying about your transmission or anything else really.

Best of luck on your project!

[sweetk30]

no one said it yet but your ALL THE WAY up there in denver co . the elevation is not helping you also . and carb to efi at this level is not even a chance unless carb is tuned in real good .

prob 4.10 gear in the rear .

drop me a pm if you need a good timing set . i have a brand new comp cam double row roller set new in the sealed box . part # 2110

[Nick_R_23]

I'll echo the suggestions of a better cam and optimized gear ratio. A stall converter will help as well.

[Pontiac1976]

I think my truck was 5400LBS Duals 2-1/2" 454,350TH 308 1500 trailer 4200 car gobs TQ yes a lot of ricer cars if pretty stock LoL at them. But the face of one of them get a chance to see you pulling car and trailer & do not lose to much ground. make your week.

[WorkinLonghorn]

The Nissan Sentra SE-R Spec V (some years) could go 0-60 in ~6.3-6.5 seconds stock with a 200 HP 2.5 Ltr. I-4.

https://www.zeroto60times.com/vehicl...-60-mph-times/

[Honest Bob]

A sentra probably weighs 1500lbs (early 90's sentras were less than 2400lbs!) less than your truck.

You could have been racing a bone stock sentra or a 2400lb turbo 300whp go cart. The Sentra SE-R is a quick car from the factory and easy to modify.

[demian5]

I had a 73 C20 suburban with 4:10 and a th400 with a allison style 6-bolt converter (stock stall I beleive) 33" BFGs. The motor was a 461 with early 70s corvette heads, a crower power beast cam, match ported 2.0 intake with long tube headers, stock ratio roller rockers (cause big blocks like to eat valve train) and a Q jet that I changed the rods in (that was originally out of a FedEx van with a small block). It ran well and would pull pretty good and gave a few vehicles a run for their money, but the weight was the killer. Thing weighed a ton or more. But towed like nobody's business and got good mileage on the freeway considering (40 gal tank and 350 carb).

I think one thing people overlook that can make a big difference is over carbing. You run something where its burning all of the fuel, then its going to have the most power.

[LT7A]

You may not be able to find that Sentra again to find out if it was stock, or the performance model, or whatever. But your truck sounds like it's set up to run pretty healthy so I think you could go out and run a baseline. Go check your 0 to 60 time and/or quarter mile time on a deserted road somewhere. Probably can snag an app that would make it pretty accurate with GPS. Once you know your truck's baseline, you'll have a better guess whether that Sentra was modified or the hot model.

[Killer Bee]

you're doing it wrong.. put a scoop of sand in the back of each vehicle with a trailer attached for the rematch, results will be overwhelming..

stay focused on what you're driving and what it was designed for.. who cares what some rice powered pos does, it'll be in a scrap yard long before your truck..

now if any one of you get overtaken by a prius, please keep it to yourself

[thirstybob]

Originally Posted by sweetk30

no one said it yet but your ALL THE WAY up there in denver co . the elevation is not helping you also . and carb to efi at this level is not even a chance unless carb is tuned in real good .

prob 4.10 gear in the rear .

drop me a pm if you need a good timing set . i have a brand new comp cam double row roller set new in the sealed box . part # 2110

Thank you

[thirstybob]

Originally Posted by LT7A

You may not be able to find that Sentra again to find out if it was stock, or the performance model, or whatever. But your truck sounds like it's set up to run pretty healthy so I think you could go out and run a baseline. Go check your 0 to 60 time and/or quarter mile time on a deserted road somewhere. Probably can snag an app that would make it pretty accurate with GPS. Once you know your truck's baseline, you'll have a better guess whether that Sentra was modified or the hot model.

I'll have to do that before my header install and maybe again after.
Good call.

[thirstybob]

Originally Posted by Killer Bee

you're doing it wrong.. put a scoop of sand in the back of each vehicle with a trailer attached for the rematch, results will be overwhelming..

stay focused on what you're driving and what it was designed for.. who cares what some rice powered pos does, it'll be in a scrap yard long before your truck..

now if any one of you get overtaken by a prius, please keep it to yourself

I probably should, it would be cheaper for sure.

lol.....I sure wouldn't have posted if I was beat by a Prius.Too funny.