355 chevy pro1 combo?

[nova72]

I have a 355 chevy with 200 Pro1 heads and a flat tappet hydraulic cam (234/244@.050,.488/.510lift,114l.s.).I am currently running a performer rpm but I also have a TeamG intake (7530) .Would the single plane be worth the swap?The engine is 9.8:1 and has a 650d.p. Holley on it currently.Also a th350 trans,3500 converter and 3.90 gear are part of my combination in a 72nova.Any suggestions for improvements would be great.

[chrisw1173]

With the cam you are running the single will hurt you and not help . For improvements change to a solid cam with about 10 more @50 get the lift numbers up and go to a 108 to 110 l.s Then you you will need more carb and intake. heck Im sure most of the guys will tell you more cam than that... haha

[want-a-be]

What are you doing with this car? Street only, track only. a blend of the 2?

I like the open plenum intakes myself. But I'm not familiar with that intake.

I might consider 1.6 ratio rockers for the cam. Do some research on what needs to be be done to compliment the rocker ratio change though. Luck favors the prepared.

What kind of cranking compression are you running? I'd leave the lobe separation alone if the cranking compression is in line. But I wouldn't go less then 110 with your compression.

Don

[CNC BLOCKS]

I have a 355 chevy with 200 Pro1 heads and a flat tappet hydraulic cam (234/244@.050,.488/.510lift,114l.s.).I am currently running a performer rpm but I also have a TeamG intake (7530) .Would the single plane be worth the swap?The engine is 9.8:1 and has a 650d.p. Holley on it currently.Also a th350 trans,3500 converter and 3.90 gear are part of my combination in a 72nova.Any suggestions for improvements would be great.

Thats a lot of split for good set of heads a single pattern cam or at the most a 4 degree and a tighter lobe sep a s mentioned would be a big improvement and more rocker on just the intake is always a plus.

With that wide of lobe sep it will kill what little dynamic pressure you have.

[nova72]

Thanks for the help,I have a cranking compression of 170-175 on all cylinders and use the car as street and occasional strip.I dont have any times yet but plan on some track time in 2 weeks.Will a smaller lsa (108-110)make a noticeable difference even with similar lift and duration numbers?I believe my cam is similar to the performer rpm grind.Also ,I have 1.5 ratio crane roller rockers all around ,a change to 1.6 on the intakes seems like a popular suggestion.Thanks again.

[want-a-be]

Thanks for the help,I have a cranking compression of 170-175 on all cylinders and use the car as street and occasional strip.I dont have any times yet but plan on some track time in 2 weeks.Will a smaller lsa (108-110)make a noticeable difference even with similar lift and duration numbers?I believe my cam is similar to the performer rpm grind.Also ,I have 1.5 ratio crane roller rockers all around ,a change to 1.6 on the intakes seems like a popular suggestion.Thanks again.

I think you have enough split already,...you need the lift on both sides. I think the 175 cranking compression is a bit low. Might tighten it up a bit,...but not under 110 lsa imo. Where is this cam installed at? Did you use a degree wheel on it or just do the dot to dot when installing?

Don

[nova72]

I installed the cam dot to dot and checked it with a degree wheel and dial indicator: Intake max lift is 109-110degrees and exhaust max lift is 119degrees.Does this sound correct ?Seems to run decent with about 11" vac. at 900rpm idle.Thanks.

[Awesome Bill]

I have a 355 chevy with 200 Pro1 heads and a flat tappet hydraulic cam (234/244@.050,.488/.510lift,114l.s.).I am currently running a performer rpm but I also have a TeamG intake (7530) .Would the single plane be worth the swap?The engine is 9.8:1 and has a 650d.p. Holley on it currently.Also a th350 trans,3500 converter and 3.90 gear are part of my combination in a 72nova.Any suggestions for improvements would be great.

I would do nothing until you got a baseline, you don't know where your at right now. The talk about the camshaft here is incorrect. Your wide lobe sep will help things not hurt. With what I consider a large cam @ .050 for what you have now is a very nice unit. I have used these cams and they work very well. You do not want to put anything with a tight lobe sep in your engine. You will have a very nice torque curve right now from 2000 rpm to 4500 rpm. Bringing the lobe seps together will not do anything and most likely hurt your performance.

This is what I would do. Borrow or beg a 500-570-600 cfm vacuum sec carb from someone, take your car to the track and base test it first with a good set up sticky tires. If you spin, you can not tell what power you are making. Shift the car @ 4800 rpm and see what it runs. Then, put the smallest carb you can find on it with a vacuum secondary and see what it runs then, I bet your going to be very surprised.

As far as putting more rocker on it, I would suggest not! Reason being, if your running an air cleaner, closed exhaust, you will pick up little to nothing. If you put a good cotton based air cleaner on it like a K&N, you pick up way more with that than any 1.6 rocker at this point.

After your runs, if you can, pull the exhaust, see what it runs? If it picks up good, pull the air cleaner off and run it again, if most likely will not pick up with either of these off unless you have a very restricted set of mufflers or very small dual exhaust.

Run your stuff in the condition it is and get a baseline first. Then go from there, never just starting changing anything until you know what not to change! HTH

[nova72]

I agree Bill,I will get a baseline first and then make any changes,if any.You are tthe first to suggest a smaller carb ,I would have figured a bigger carb would be the way to go ,and ,if anything my 650 d.p. would be on the small side.I have 70pri and 76 sec. jets in it now and it seems pretty good. Thanks.

[3V Performance]

Before you bolt on anything might want to put a vacuum guage on it and record wot readings. Post your findings. Anything over 1" might warrent a larger carb. Anything under lean towards smaller.

[nova72]

I dont have a vaccuum gauge in car,but I'll get some more hose and hook up my hand held gauge to get some vaccuum numbers in the car at w.o.t. Does anyone have a guess on any horsepower numbers ,or has anybody used a similar combination ?Just curious ...Thanks.

[Awesome Bill]

I agree Bill,I will get a baseline first and then make any changes,if any.You are tthe first to suggest a smaller carb ,I would have figured a bigger carb would be the way to go ,and ,if anything my 650 d.p. would be on the small side.I have 70pri and 76 sec. jets in it now and it seems pretty good. Thanks.
I had a customer Stacey Tubbs, years ago pull a dual plane off his 350 4 speed car and install that intake. It made that engine bad __s for sure over what we had. We are talking 1986. His 1974 Nova was pretty much the fastest thing on the street for its engine at that time around the local tastee freeze cruizin. I was working hard on starting the business then and a family. Seems like just yesterday. Either way, it really picked his engine up very well. RPM and power especially with his 4 speed. I seen him take some pretty stiff stuff out on the street. Most likely a real 12 second street car. I would still get a baseline on a good clean pass with no tire spin. If it spins you have to keep doing it over until you get a dead hook. When that happens, you can then start changing 1 thing at a time and write it down. If it don't work put it away, it may work later.

[nova72]

Thanks Bill,I'll take your advice,and get it to the track before any changes.I'm going this Friday for test and tune,the track is about 50miles from my house ,I'll drive it there(no trailer).I'm a good bit nervous as I have never been down the track before...ever.I'll bring some extra jets , a timing gun,and a couple 5gallon gas cans with me ,as I only have a 12 gallon fuel cell.

[Awesome Bill]

Thanks Bill,I'll take your advice,and get it to the track before any changes.I'm going this Friday for test and tune,the track is about 50miles from my house ,I'll drive it there(no trailer).I'm a good bit nervous as I have never been down the track before...ever.I'll bring some extra jets , a timing gun,and a couple 5gallon gas cans with me ,as I only have a 12 gallon fuel cell.

Bring a cell phone also to call a tow truck. It does happen.

[EWC]

My Buddies son has a 11 to 1 355 in a Nova with Pro1 200's and it has a Comp Cams XE284H Cam in it with a Prosystems Dbl Pump on it . He put a Team G on the Car and it went no faster than the RPM Air Gap ran the same actually 12.00 @ 110 mph

[nova72]

I'd be more than happy ,if my Nova can get into the 12s.His combination sounds similar but quicker than my set-up.

[Awesome Bill]

My Buddies son has a 11 to 1 355 in a Nova with Pro1 200's and it has a Comp Cams XE284H Cam in it with a Prosystems Dbl Pump on it . He put a Team G on the Car and it went no faster than the RPM Air Gap ran the same actually 12.00 @ 110 mph

well one thing for sure, his mph and et match so @ 3500lbs, he is making a real 350hp. Yours should do that easily as long as you don't have tire spin issues. Take it slow and buy a set of good drag radials that will dead hook the car. If its a Chevelle, put a rr air bag in and adjust it up in pressure until the car leaves dead straight. If its a Camaro or leaf spring car, make sure it does ot wrap the leaf springs up. A good cheap set of bars will do the job. Let us know.

[nova72]

well one thing for sure, his mph and et match so @ 3500lbs, he is making a real 350hp. Yours should do that easily as long as you don't have tire spin issues. Take it slow and buy a set of good drag radials that will dead hook the car. If its a Chevelle, put a rr air bag in and adjust it up in pressure until the car leaves dead straight. If its a Camaro or leaf spring car, make sure it does ot wrap the leaf springs up. A good cheap set of bars will do the job. Let us know.
Luckily,my Nova already had a ladder bar /diagonal link set up with adjustable coil overs in it when I bought it .It was an unfinished project car shell with no trunk floor or interior I found in a field .The suspension isn't too street friendly ...but it should give me decent performance at the track,with some adjustability.

[sully racing]

im running a LT1 chevy roller cam motor and when i built this i got th performance that i wanted but now i just put a standard transmission and running higher rpms but now at 4500 rpms im starting to float valves. what i found out was that i got the wrong valve springs i got reg.hyd.valve springs but i need hyd. roller valve springs i found out there is a .060 thousands difference in hight my ? is can i run a .060 shim and would i be ok ..

[lun40119]

It might be making more than the 350HP. We have guys here that make dyno proven 580+ HP, and only show mid 300's at the track. So don't get down on yourself on what others say. :) Even when the mph/et matches ;)

[want-a-be]

im running a LT1 chevy roller cam motor and when i built this i got th performance that i wanted but now i just put a standard transmission and running higher rpms but now at 4500 rpms im starting to float valves. what i found out was that i got the wrong valve springs i got reg.hyd.valve springs but i need hyd. roller valve springs i found out there is a .060 thousands difference in hight my ? is can i run a .060 shim and would i be ok ..

Sounds to me like your springs are too light. Measure your installed height and buy the correct springs and retainers for the application. Make sure whoever sells them to you knows what they are doing or you may end up in the same situation. If it is a hydraulic roller then you need about 145-155 pounds on the seat.

Don

[nova72]

well one thing for sure, his mph and et match so @ 3500lbs, he is making a real 350hp. Yours should do that easily as long as you don't have tire spin issues. Take it slow and buy a set of good drag radials that will dead hook the car. If its a Chevelle, put a rr air bag in and adjust it up in pressure until the car leaves dead straight. If its a Camaro or leaf spring car, make sure it does ot wrap the leaf springs up. A good cheap set of bars will do the job. Let us know.

Got to the track Friday and had 5 passes ,my first few were terrible...nervous as hell...I ran a best time of 14.812 @97.57mph. Saturday I did much better,my best time was 13.642@97.93 with a1.998 60 ft. time.I shifted the car at 5500 and have a 6000 chip in my msd box.My best 60 ft. was 1.931.I am certain that this combination can go faster,but I didn't change any jetting or timing with the car .I still have to get a few more passes to establish a good base.I really had fun after the nerves settled down and I'll be back at the track again soon.

[Awesome Bill]

Got to the track Friday and had 5 passes ,my first few were terrible...nervous as hell...I ran a best time of 14.812 @97.57mph. Saturday I did much better,my best time was 13.642@97.93 with a1.998 60 ft. time.I shifted the car at 5500 and have a 6000 chip in my msd box.My best 60 ft. was 1.931.I am certain that this combination can go faster,but I didn't change any jetting or timing with the car .I still have to get a few more passes to establish a good base.I really had fun after the nerves settled down and I'll be back at the track again soon.

O.k. now you have a decent baseline. Take the chip out and put a 7500 rpm one in. The chip does not come into play only if you break something. Then it keeps the engine from hurting itself maybe?

What was your crossing rpm of the engine? This will tell me what your torque converter is doing and where to go from here. One thing for sure from one day to the next, your getting comfortable with your car. You will most likely, the more you race it and become familiar with the combo, get better e.ts. Look where you where the first time out? Your almost a full second faster.

It is true, that its more just getting used to the combination. Just think of what you would do if it was a 4 speed car with over 550 hp and never race a stock suspension car. Either way, it always gets better with you becoming more familiar with the whole thing from burn out to the finish line. If you had fun, you done good. Now you will want to hone the racing stone!

[nova72]

My r.p.m. was between 5000 and 5500 r.p.m at between 97 and and 98 m.ph. at the finish line.I'm running 28" tall b.f.g. drag radials.and 3.90 gears.You are right about getting comfortable with my set up, there seems like lots to learn before even attempting any changes.I have a 7000 chip that I can put in and try .I feel there is more potential to my set up,The cam specs(summit k1107)state a power range of 3000-6500 ,and the 200cc pro1's should flow to those levels ,hopefully.The car seems like it's still pulling strong through the finish,.Thanks.

[lun40119]

If it is 5000rpm at 98 mph, you are slipping around 7.5%. If it is 5500rpm you are slipping over 18% through the converter. It would be nice if you knew the exact crossing rpm. This is pretty common with the cookie cutter converters you get from the mail order stuff.

I have driven and raced those converters, and trust me, a good converter is where its at. Ive got an ATI, but, they are by no means the end all answer all. There are several great converter companies out there. Good luck fella.

[Awesome Bill]

My r.p.m. was between 5000 and 5500 r.p.m at between 97 and and 98 m.ph. at the finish line.I'm running 28" tall b.f.g. drag radials.and 3.90 gears.You are right about getting comfortable with my set up, there seems like lots to learn before even attempting any changes.I have a 7000 chip that I can put in and try .I feel there is more potential to my set up,The cam specs(summit k1107)state a power range of 3000-6500 ,and the 200cc pro1's should flow to those levels ,hopefully.The car seems like it's still pulling strong through the finish,.Thanks.

With a 3.90 gear and a 28° tall tire, you should be crossing the finish line @ 4550 rpm with no slippage. So Jakes 7½ slippage is right. But if you going threw @ 5500 you have 15% slippage. These are areas that you have to know for sure. Either way, the cam will be dead in the water @ 5000rpm because the valve train will not like anything over that. A good solid lifter will work better and most likely then maybe pull to 5500-5700rpm. Either way, get some good solid base line runs and then ring us back.

[nova72]

With a 3.90 gear and a 28° tall tire, you should be crossing the finish line @ 4550 rpm with no slippage. So Jakes 7½ slippage is right. But if you going threw @ 5500 you have 15% slippage. These are areas that you have to know for sure. Either way, the cam will be dead in the water @ 5000rpm because the valve train will not like anything over that. A good solid lifter will work better and most likely then maybe pull to 5500-5700rpm. Either way, get some good solid base line runs and then ring us back.

Thanks guys,yes it is a cheaper brand converter ,it's an api stinger converter(not ati) 10" rated at 3500 stall.I'll keep using it for a bit while I get some solid baseline times.I'll make sure to note more specifically what trap rpm,shift points and launch r.p.m. next time at the track.My mind was on the basics and just getting used to the car for my first few passes. ..Bill, In general are hydraulic flat tappets only good to about 5000 r.p.m.?If this is the case I'll definitely be considering a solid cam swap during the winter.

[Awesome Bill]

Thanks guys,yes it is a cheaper brand converter ,it's an api stinger converter(not ati) 10" rated at 3500 stall.I'll keep using it for a bit while I get some solid baseline times.I'll make sure to note more specifically what trap rpm,shift points and launch r.p.m. next time at the track.My mind was on the basics and just getting used to the car for my first few passes. ..Bill, In general are hydraulic flat tappets only good to about 5000 r.p.m.?If this is the case I'll definitely be considering a solid cam swap during the winter.

Yes, 5000-5500 is it. Everyone will say they are good to 6000 - 7000 but this is not correct. You can get them to work but with your combination. You can tell by after getting a good baseline, put the shift points up 500 rpm. If it goes faster, it is most likely making more power. This also could be the carb is to big, the converter is to tight along with some other things. If the carb is to big, the increased air speed really picks up a ton. If the converter is to tight, the drop back in rpm due to gear ratio's helps the engine climb back from a higher point. People don't even think about these things, they just listen to stuff that should not even be put into print. Either way, trial and error is your course right now. Pay attention.

[nova72]

There is a charity car show next Saturday ,they have a dyno set up and $60.00 gets you 3 pulls.Do you think this is worth it?Never had the car dyno'ed before ,I would get the chance to try different jetting and timing combos or am I better off getting a good baseline at the track and tuning there?

[lun40119]

60.00 for 3 pulls with an O2 is a good deal. Are you sure that you get time to tune between pulls. Alot of times when they do that stuff at shows it is more for show, and bragging rights so they try to get the cars through pretty quickly. I would do it for fun, but don't get pissed when you see the number. Odds are, your car might be a little more inefficient than you think, though the driveline. :)

[nova72]

I'll give it a try ,just for fun .You're probably right about being a short time between pulls,no time to make any considerable changes.I'm not expecting anything amazing from my car ,but I'll get a kick out of the dyno's ability of keeping people humble.

[Awesome Bill]

I'll give it a try ,just for fun .You're probably right about being a short time between pulls,no time to make any considerable changes.I'm not expecting anything amazing from my car ,but I'll get a kick out of the dyno's ability of keeping people humble.

They really tell you nothing and are very inaccurate. But it is fun. Like Jake said, don't be disappointed when you see the paper work. They really don't care what your car does, its all for the money. Track testing and a real dyno are really the only way to find power. Now if the guy duplicates the chassis pulls and gives you real time to make changes, you can find a little hp. But I doubt he is going to let you do all that while up on a lift!

[nova72]

Got to the track a second time and things are starting to come together.My best e.t. was 12.88 at102.88 mph ,my 60' was 1.784.This seems like a huge improvement from my old best time of 13.64.I shifted the car at 5800 and it seemed better .The only other change I made was replacing the 6000 chip for a 7000 chip in my msd and adding 2degrees of timing.I still have the 650 holley on it with 69-76jets in it and jetting is what I'll try to tune next time I get to the track.The plugs look good after street driving but I haven't checked them right after a pass down the 1/4.

[Awesome Bill]

Got to the track a second time and things are starting to come together.My best e.t. was 12.88 at102.88 mph ,my 60' was 1.784.This seems like a huge improvement from my old best time of 13.64.I shifted the car at 5800 and it seemed better .The only other change I made was replacing the 6000 chip for a 7000 chip in my msd and adding 2degrees of timing.I still have the 650 holley on it with 69-76jets in it and jetting is what I'll try to tune next time I get to the track.The plugs look good after street driving but I haven't checked them right after a pass down the 1/4.

you keep playing with that thing and not changing every part every one tells you and you'll be in the 11's before you know it. Now your starting to get it. 102mph will yield 12.70's. Good job.

[nova72]

you keep playing with that thing and not changing every part every one tells you and you'll be in the 11's before you know it. Now your starting to get it. 102mph will yield 12.70's. Good job.

Thanks Bill,I'm going to the track again this weekend(weather permitting).I don't think I'll make any changes except maybe raise my shift point to to 5900-6000 and see if the car likes it.This is the last race weekend of the year and I don't want to make any changes as the car seems to be working pretty good.A few racers have suggested I try my 750 speed demon ,or a 750 holley and figure it would pick up a few tenths??? ...however,my combo has to work well on the street also as I have to drive my Nova to and from the track.

[Awesome Bill]

Thanks Bill,I'm going to the track again this weekend(weather permitting).I don't think I'll make any changes except maybe raise my shift point to to 5900-6000 and see if the car likes it.This is the last race weekend of the year and I don't want to make any changes as the car seems to be working pretty good.A few racers have suggested I try my 750 speed demon ,or a 750 holley and figure it would pick up a few tenths??? ...however,my combo has to work well on the street also as I have to drive my Nova to and from the track.

try the shift points with what you got, then try the shift points with the 750. This will clearly wake the DART board up with your findings!