|02-13-2013 03:16 PM|
Sounds like you already buy race gas by the drum. What's one more? Me, I hate to admit I've made a serious uncorrectable blunder. Now, with that said, it doesn't sound like you have the skills or the inclination to fix this problem yourself. If you did, you would pull it apart on the stand where it sits and see what you got. Most folks I know would never buy a used race engine from anything less than a reputable engine builder. So...that leaves you with the option of breaking it down and selling for salvage the parts you don't use. Use the block, the rods and crank and buy new parts that fit what you intend to do with the car. 500 HP on pump gas is not difficult with a 355 if you use a set of AFR or comprable heads and a hydraulic roller cam. It's at the upper range of what you can expect without power adders.
Maybe the guy you bought it from will buy it back at a discount you can live with.
|02-09-2013 11:02 PM|
|Shawnb||Not trying to "market an engine". Marketing it would include including my contact info, which I wont do. Ive never bought or sold a used engine. Im also not familar with GM or high compression race gas engines. I bought it based on the idea I would modify it to run on 93. Based on responses from people like yourself it sounds like its not a good idea to take it apart. Thats why Ive used this forum for advise from others with more experience like every other person who has posted a question looking for help here. Chill out.|
|02-09-2013 08:46 PM|
You bought it you should have a clue.
It is worth what someone wants to pay you for it.
|02-09-2013 08:35 PM|
So based on the specs of the engine carb to pan ready to run with all accessories what would you sell it for. Anyone chime in. Im not sure???
thanks in advance.
|02-09-2013 05:43 PM|
It is a high quality GM over the counter casting. With proper preparation and porting, they work very very well
and make great power. They are intended to be prepped and ported by the engine builder.
The have a as cast port that does not flow huge in stock as cast form but the port walls are pretty thick for
porting. and there is lots of meat to work with. They turn out real good with correct full porting and prep. Capable of well over 500hp on a racey engine.
Today there are many more cylinder head choices to start with.
But they are still a good powerfull head for those that like to port their own stuff.
But nothing junk about them. Assuming they are not all used up. Race parts live a hard life.
Often these heads get angle milled for high compression for a race motor/typical dirt tract motor.
the casting number ends in 034.
Good used properly ported and preped 034 Bowtie heads that are not damaged, fubared or cracked are a good buy and
have good resale value. Some racing classes require this head.
A used up or damaged Bowtie head is not worth a lot to anybody.
|02-09-2013 01:59 PM|
The info is helpful. I think based on what I've read it sounds like the set up I have is a good engine. I dont think I want to mess with it. I think that I may try it in a car and have a careful tune and mix some 110 with the pump 93. Worst case it pings and I pull it and sell it. Or I may sell it as it is and buy/build another. I knew the compression may be a factor when I bought it. I bought it @ Iola old car show the last day of the swap meet. He did not want to bring it back home. I may not be a Cheve expert like some who have responeded but im not new to muscle cars amd HP motors. I wouldnt have bought it if it didnt sound/run right. Its solid.
You made mention of if the guys were idiots they woudnt have used those quality Bow Tie heads 2.02. Whats different from these to any other chevy small block 2.02 head?
|02-09-2013 12:24 PM|
Ok got ya. Yeah but should be around 500 if built well. Usally when people go to the effort of buying gm performance products heads they usally have a good idea of how the rest of the build should go. If it was built by clowns it would not have those heads so sounds like a good engine.
If i had a parts list i could come up with a price. As far as sbc for a bracket car that is a perfect setup. I would bet someone spent more than a few bucks to have it built.
In the sbc world blocks are a dime a dozen so are parts to build them up. Mild builds can be very inexpensive. What you have sounds like a nice little gem. It would be a shame to pull it apart. But sbc are much less forgiving than big blocks.
Here is a dcr calculator problem is i dont think any amount of cam is going to let you run 13:1 on the street and use iron heads. But i have seen someone pull off 12.5:1 on the street but it was a fair weather car. Now the right cam and a few gallons of 104 octane per tank full you might make it work with careful tuning.
United Engine & Machine Co. Incorporated
Fyi i got a feeling from this post that you got a few bucks to spend on the right stuff. The LS motor is awesome for street cars. Price is a lot more than a gen I. But many ppl have them over 800 hp with turbos and mostly stock engines. Even with the 5.3 will make a butt load of power with simple setups. The 6.0 from an escalade is good for 300 hp In stock trim. A cam and some exhuast work 350-400 is not hard to find. It is a lot more work to install but work dam well and will last 100k miles no sweat. Also makes for a very smooth and fast car. Only reason most ppl dont upgrade is cost. The heads and block are a leap forward in tech. The stock big valve LS heads flow better than some aftermarket heads for the gen I.
Sorry for the long post hope at least some of the info is helpful.
|02-09-2013 12:22 PM|
1. the cranking compression pressure will not predict the octane requirement of a engine.
2. the only way to lower the cranking compression ( and the calc DCR) is to
make the intake valve close latter. Overlap does not effect this.
This will not make a 13:1cr engne run on pump gas.
As the cranking compression, dynamci compression and the real engine cylinder pressure that is created in the runnng engine at WOT @ rpm are not related.
You could install a bigger better cam that traps more air at RPM and the
cylinder pressure will end up higher, the engine power ends up higher and the
octane requirement actually increases.
If you want to stop the 13:1cr engine from knocking on pump gas reduce the spark advance. It is just that easy.
Or don't open the throttle.
if 36deg BTDC is normal just set the timing at 28 to 30deg.
Yes you will give up some power. There is no free lunch.
and changing the cam will not fix it. but reducing the spark timing @ WOT will allow it to run on pump gas
in a limited fashion. If you just got to do that.
If the 13:1cr engine has a big piston dome you will not lower the compression ratio enough for pump gas by changing the cylinder heads.
You best move would be to change the pistons.
You can do it right the first time or do it right after it blows up. your choice.
You want 10:1 cr not more than a measured 10.5:1 cr on pump gas.
On a 355 that means a 58-64cc head and a flat top piston.
You were dumb enough to buy this 13:1 cr motor. Now,,,Are you smart enough to fix it right? Before or after you damage it on pump gas? Or smart enough to just resolve to run it on high octane gas or Methanol.
If this 13:1cr engine has a flat top piston then you can lowe the compression enough for pump gas by
swapping cylinder heads.
One of those mini inspection cameras will allow viewing the piston top thru the spark plug hole.
|02-09-2013 10:32 AM|
Hook up a battery and run a compression test. Cranking compression over 215 or so will be hard to get by on pump gas. You can either swap heads or run a cam with more duration or a tighter LSA. Increasing overlap will lower the dynamic compression.
|02-08-2013 11:21 PM|
?????? Who said anything about "a stock Super Bee and stock GT500" ???????? 1969 1/2 A12 six pack Super Bee Hemi orange restored 6/2012. 543" ci stroker, Edelbrock heads, 3.5" hookers, 3 worked holley 500 cfm carbs, hydraulic rollers cam, lifters, rockers+++ Dyno done 4/2012 715 ft lb torque. Thats the orange Bee in the pic earlier in this post.
Oh ya "stock GT500" Ford racing 2.3L TVS supercharger, Kooks 3" race headers and exhaust, high flow elbow + twin TBI. VMP performance underdrive supercharger pulley kit 2.59" boosts 18 PSI (double OE). Eibach lowered suspension. +++ too much to list here. Above are the highlights. Yes I have the engine and chassis dyno with many pulls. Videos too. All 3 cars are in previous pics in this post.
Most of my performance experience is in Mopar and Ford. Thats why I was asking you guys what you think the 355 Chevy as I posted the specs prior is worth. ?????? Any other ideas of value?
But I agree, 500 hp is much more than "STOCK" Super Bees and Shelbys...
|02-08-2013 06:20 PM|
|02-08-2013 04:37 PM|
Price would need to be added up and parts priced. Then add in the machine work and builder time. Add all together and cut it in half since the motor is used and that should be around your price. Or between 2500 to 5k depending on the guts. New with forged internals and all the right toys 15k.
|02-08-2013 01:02 PM|
|02-08-2013 11:02 AM|
I wouldnt need an engine that is good for traffic or cold weather. This would be a cruiser/street racer. I dont think I want to take apart this combo. The only thing I wanted to do was replace heads to help with detonation. I didnt know if these heads were any good. I wouldnt want to trade anyone for a stock type of motor. 500 hp would be perfect for what I want to do. In fact if what I use is 500 hp is would be the least powerful of the muscle cars I have (2 SuperBees and Shelby GT500). I was just not in love with needing 110 gas.
What do you think this engine combo carb to pan is worth complete?
|02-08-2013 10:13 AM|
In order to make it a street car engine you will need to replace the cam and pistons. Now to make it a good smoother runner for all weather and street only use traffic in 100 degree weather or very cold out. You will need to swqp out the intake and carb as well. And then the heads will be over sized for the parts you have.
The motor has value as it sets. I would sell it to a racer that will be happy to have it as is. Then buy new trans and stock engine for the same money. Simply replqcing the pistons or swaping the heads will make the engine under perform and possibly very tempermental to hot and cold and basic rigores of street driving. I spend two hours in heavy traffic every morning so a street engine must perform well for me. You may be willing to deal with more issues if you can drive in good weather and no traffic.
Do you live on the us east coast. I got a few engines to trade if your interested.
Fyi most drag racers will be happy to trade you something street able for that engine. If you have a race car project this is the motor for it. Junk yard has plenty of street engines that can be bolt in ready. Ls motor would even be better for the street.
Should be firmly into the 500hp range. Nice build would hate to see it ripped apart. Never good idea to dig into a sealed engine if you dont need to.
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