ok i want to here from the people that have 327 tpi motors in their thirdgens. does the tpi just kill the high revvin of the 327. i was thinking of doing a 327 with a fully upgraded tpi system so that i can have high end revs and low end torque. do i just want to stick with tpi or would something like superam be even better? thanks.

 

The TPI kills the high revs in a 305...... what do you think it would do to a 327?

 

well iv seen a few people that have 327tpi engines and didnt drop the tpi system on them. there is good power all the way thru with systems like superram and highly upgraded tpi systems that people have used on their higher end motors and i think a good tpi like system would give nice torque all the way thru without choking the 327 and give really nice mpg along with pretty good driveablity. thats what im looking for an good powerful engine that has power all the way thru but that will last a long time and that is drivable and gets good mpg.

 

Stock TPI starts running out of air at what, 4500 or so RPM? The only real advantage of using a 327 over a 305 for TPI is the larger bores allow for larger valves... you might as well go 350 to keep the longer stroke too, unless you happen to have a ready-to-go 327 laying around.

 

High revs have nothing to do with cubic inches, it has to do with airflow. You can make a 305 or 350 rev just the same.

I wouldnt lose any sleep over putting a TPI on a 327 you have, but I would surely not change from a 305 or 350 to get the mythical gain of a "high revving" 327 or 302.

 

I just bought a 91 Z that for whatever reason, someone along the way switched to a 327. At least thats what the numbers say it is and as far as power...can barely get it to turn the tires power braking it...

It'll definately be getting the 350 treatment soon. If it matters, it came with a TPI 305 and all that was switched was the short block and I dont know what was done as far as tuning.

 

327's are nice but when it comes down to it there is no replacement for displacement i happen to have a 327 all put together minus intake and heads...i was kinda thinking that itd probably be close to what the stock 305 from my camaro would put out? i am only thinking of the swap because the *******s at pepboys when replacing srings for me somehow managed to pop a hole in my oil pan and now i have bad main bearings...if bolting up the topend from my 305 can be done it will only be temporary until i can afford the money for the 350 swap or i may retire her as a dailt driver and go big and get a 572 crate and run her at the track

 

Will the intake and tpi setup from a 305 bolt to a 327 without changing heads and do I need new injectors

 

Um why would yiu think the b327 would be same as 305?? Makes no sence. That woild be like saying the 327 would put out more power then 350. More cubes is more power.

 

you'd need better heads, too, and cam for a good 327. Not just a better flowing induction system.

a properly set up 327 is a thing of beauty, and fun

Its true a 350 and 327 cost the same to build (good running ones anyway) but sometimes its just fun to be different. Why be like everyone else?

 

Would a 350 intake manifold bolt to stock heads That came on the 327

 

86 and older, yes. Anything newer, no. Unless it's from a 'vette.

 

It is from a Corvette I'm not sure on what year vette though

 

What heads are on it? Could be your rear end gears too.

 

Aren't those double hump heads on the 327? If so, i have heard of a lot of problems with getting accesories like the alternator, Ps, etc bolting up to them.

 

I'm not sure what heads they have I was basically wonder if I could bolt every thing form my 88 iroc 305 auto to the 327 block and heads with no major issues

 

This is the most rediculous statement ever.. the short stroke equals higher RPM.. the TPI system is limited to 4800 ish RPM.. the 305 & 350 stop producing power at 4800ish
So how will 327 shorter stroke higher reving engine utilize its range... When the TPI system is maxed out

 

Cam and heads set the rpm range, not the stroke. If you ran the proper internals you can make a long stroke motor rev just as high although piston speeds/stresses will be great. Generally higher rev motors are built with shorter strokes, longer rods, smaller compression height pistons to limit stresses imposed on the rods/rod bolts/bearings but its not the end all/be all of design. There are 434" 4" stroker motors revving to 8 grand out there.

A 327 with L98 cam and heads wont rev any higher than the other motors....it will peak hp at higher rpm than 350 but not as high as the 305 given same heads/cam.

 

A 350 is a 327 block with a 3.48 stroke.. but there is a crank vent built into the rear valley.
You will also have a offset from your current 1 piece crank flexplate.. to a 2 piece crank

 

You are correct the cam & heads control the upper RPM band... Changing the stroke will shift the power band decreasing bottom end. & torque
PS The stroke will effect RPM... take a bicycle simple form.. with same gears.. small cranks you need to pedal harder and faster... Then with larger cranks

 

So can I bolt my stock intake and accessories from a 305 to a 327 block and heads

 

I don't think so. If you use the tpi heads you can tho.

 

also, I would use the tpi cam , the 327 cam may have too much duration.

 

Would there be clearance issues tho would they bolt on or would I have to have them milled

 

You will need a freezeout plug for the top rear block vent... You will need a different flex plate..if your using your stock heads a SBC is a SBC... If your bolting up the 327 vette heads. you will need to oval out and re-seat the center bolt holes on your TPI intake.

 

I think they should be fine. I would have the heads re-surfaced tho. If I were you I would double check some of the 327 tpi threads on here tho.

 

I think what 88gta3508 said is true. If you do use the 327 heads and cam , then your car will live in the higher rpm range. Not the best thing for tpi. Since tpi shines in the lower rpms and has tons of torque. Now a car that shines in the higher rpms usually does it with a better gear than your 273. A 373 gear would help get you to those higher rpms faster where your car would now live, but you have a 700r4 auto trans. First gear in a 700r4 is like having a 373 already. Of course you could try and start off in D2 but it will still start you off in 1st like that. So, even If you put tpi intake back on those 327 heads I think you would have a mis-match of power bands. your car may be a dog. I would go for the tpi heads, cam, and tpi intake system. Or you could use the 327 heads, cam , and something like a holley stealth ram ( essentially ,a tunnel ram intake for high rpms),but you would probably not like that combo with a 273 gear either . Also, you may have some problems with getting your accesories to hook up. You may need to get the 327 heads machined , if it is possible. I would opt for all of the tpi stuff to go back on that 327 motor if i were you. Like one of the other members said, you need a different flexplate and some other minor things too.

 

I put a 327 crank in a 400 block with TPI on top.It was a great combo.It had the torque of the TPI but came up to top rpm real fast.It was one fun motor.

 

you wanna build something cool--- a 283 crank in a 327 block to make a "ford' 302! put 350 tpi heads on it because now you can take advantage of the larger bore with bigger valves and less shrouding.

 

What heads and cam did you use? Did you use the tpi heads and drill steam holes?

 

I used world products sportsman heads.

 

any thing under 400 cid .. WHY?

 

So this is from Holdener on a 383 with a healthy cam. The CAM prevents the intake from really dropping off on power

Test 1 is stock TPI

Test 2 is ported lower TPIS big tube runners and a ported plenum.



Test 2

 

That's interesting, but not really informative. What is the left (vertical) axis graduation? Kilowatts, Joule-Seconds, Newton-meters, Kcal/Cal, power factor of the dynamometer, or something else?

Also, what 383? Is it a "modern" overbored 350 stroked out, or a de-stroked Mk IV big block? Nearly everyone here remembers our member "Smitty" who was putting insane power numbers out of a "305" and many didn't believe the claims. Then everyone found out that the "305" was indeed 305 CID, but was the product of a de-stroked 4" bore engine.

Details.

 

that's just the tpi test that's been posted here for decades now. Holdener made a video highlighting the test and has also been posted numerous times.

 

1) Left axis is “power level” in torque and HP represented by the 4 lines in each graph

2) I don’t know of any de-stroked big blocks that are able to run a TPI system from a SBC
I also don’t know of any other Chevy 383 combos that aren’t 4.030 bore X 3.75 stroke

 

Mercruiser 6.3L, GM HT383 or ZZ383 is 4.00x3.80.

From memory a 0.030" over 400 (4.155" bore) with a 3.48" crank is also a 383.

Holdener tried TPI on a L99 265 baby LT1. It lost top-end power compared to the short runner LT1 intake.

 

Yeah there are exceptions to the 4.030x3.75 of course.
Out of 100 383’s 99 of them will be the 4.030x3.75 build

ALL engines will lose top end with a TPI and that 4.3 test demonstrates the TPI/327 combination won’t do what some in this thread think it will

 

377.49 cubic inches

 

My math says 382.9. Not sure what equation you're using.
4.185/2=2.0925
2.0925×2.0925×3.48×3.14159=47.87×8=382.9 sooo ahh 383